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What If the Past_ Present _ Future Exist at the Same Time_ · Boring Science

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  Speaker 1: Hello, and welcome to Boring Science to Sleep, a quiet
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  Speaker 1: place where science becomes slow, soft and easy to drift through. Tonight,
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  Speaker 1: we're going to gently explore the strange possibility that the past,
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  Speaker 1: the present and the future may not be as separate
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  Speaker 1: as they seem. Not to learn everything about time, but
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  Speaker 1: simply to notice it slowly, calmly and without needing to
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  Speaker 1: reach any final answer. Before you settle in, If you
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  Speaker 1: truly enjoy these calm journeys through interesting ideas in science,
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  Speaker 1: you're welcome to like this video and subscribe, only if
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  Speaker 1: it feels right for you. And when you're ready, let
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  Speaker 1: me know in the comments where you're listening from, and
• 0:43
  Speaker 1: what time it is right now. It's always a quiet
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  Speaker 1: joy to see how many places and moments gather here together. Now,
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  Speaker 1: dim the lights, maybe let a fan hum softly in
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  Speaker 1: the background. and allow your body to become a little
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  Speaker 1: heavier against whatever is supporting you. There is nothing to do,
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  Speaker 1: nothing to solve. You are safe. You can simply listen
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  Speaker 1: and drift, while we slowly step into the strange and
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  Speaker 1: quiet nature of time. Imagine that you are lying comfortably
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  Speaker 1: in a quiet room. The lights are low, the air
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  Speaker 1: is still, and somewhere nearby, perhaps on a wall or
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  Speaker 1: beside your bed, there is a clock. You may not
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  Speaker 1: even be looking at it. You may only be able
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  Speaker 1: to imagine it. A small circle in the darkness, with
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  Speaker 1: hands moving so slowly that you almost forget they are
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  Speaker 1: moving at all. Tick. A little silence. Tick. And another
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  Speaker 1: little silence. You already know what the clock seems to
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  Speaker 1: be telling you. This is now. This moment is happening.
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  Speaker 1: The previous moment has gone. The next moment has not
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  Speaker 1: arrived yet. And somewhere between those two things... there is
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  Speaker 1: this quiet place you call the present. It feels so
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  Speaker 1: ordinary that you rarely have a reason to question it.
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  Speaker 1: When you say, I am here now, the sentence seems
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  Speaker 1: almost too simple to deserve examination. You are here. You
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  Speaker 1: are listening. The room is around you. Your breathing continues gently,
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  Speaker 1: and the clock, if there is one nearby, continues to move.
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  Speaker 1: For most of human history, It was natural to imagine
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  Speaker 1: that time worked something like this everywhere. A great invisible clock,
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  Speaker 1: quietly ticking behind the universe, keeping the same rhythm for everyone.
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  Speaker 1: A clock on Earth would agree with a clock far away.
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  Speaker 1: A clock beside the moon would agree with a clock
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  Speaker 1: near a distant star. And if two events happened at
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  Speaker 1: exactly the same time, it seemed reasonable to imagine that
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  Speaker 1: the entire universe could, in principle, agree about that shared moment.
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  Speaker 1: Time appeared to be the background against which everything else happened.
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  Speaker 1: Space was where things were. Time was when things were.
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  Speaker 1: And the two seemed separate enough to feel almost obvious.
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  Speaker 1: But there is something very strange about the universe that
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  Speaker 1: becomes easier to notice when you stop thinking of yourself
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  Speaker 1: as perfectly still. Right now you may feel completely motionless.
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  Speaker 1: Perhaps your body is resting against a mattress, a sofa,
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  Speaker 1: or a chair. Your hands may be still. Your head
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  Speaker 1: may be still. Even your breathing may have become slow
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  Speaker 1: and quiet. And yet you are moving. The earth beneath
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  Speaker 1: you is turning. The earth is travelling around the sun.
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  Speaker 1: The sun itself is moving through the Milky Way. And
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  Speaker 1: the Milky Way is moving too, as part of the
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  Speaker 1: enormous structure of the universe. There is no special cosmic
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  Speaker 1: platform waiting somewhere in space, holding up a sign that says,
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  Speaker 1: this is absolute stillness. There is no universal speedometer showing
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  Speaker 1: the one true speed of everything. Instead, motion is always
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  Speaker 1: described relative to something else. You can be still relative
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  Speaker 1: to your bed while moving relative to the earth. You
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  Speaker 1: can be moving with the earth while moving differently relative
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  Speaker 1: to the sun. And the sun can be moving relative
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  Speaker 1: to other stars. None of these descriptions has to be
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  Speaker 1: the one secretly correct description. They are simply different ways
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  Speaker 1: of describing relationships between things. This sounds like a small idea,
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  Speaker 1: almost too small to matter. But it quietly opens a door,
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  Speaker 1: because once you stop imagining that the universe has one
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  Speaker 1: privileged state of rest, you can begin to wonder whether
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  Speaker 1: time itself is quite as universal as it first appeared.
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  Speaker 1: This is where the work of Albert Einstein begins to
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  Speaker 1: change the picture. Einstein's theory of relativity does not simply
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  Speaker 1: say that everything is relative in the vague sense that
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  Speaker 1: nothing matters. It says something much more precise and much
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  Speaker 1: more beautiful. The measurements of space and time can depend
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  Speaker 1: on how you are moving relative to something else. And
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  Speaker 1: that means that two observers can sometimes measure the passage
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  Speaker 1: of time differently. even when both are using perfectly good clocks. Imagine,
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  Speaker 1: very gently, two identical clocks. They begin together. For a while,
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  Speaker 1: there is no difference between them. Then one clock remains
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  Speaker 1: quietly on Earth, while the other travels through space at
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  Speaker 1: a very high speed. When the two clocks eventually meet again,
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  Speaker 1: they may not have recorded exactly the same amount of
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  Speaker 1: elapsed time. Neither clock has become confused. Neither clock is broken.
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  Speaker 1: Neither clock has made a mistake. They have simply followed
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  Speaker 1: different journeys through space and time. You can almost imagine
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  Speaker 1: the clocks as two quiet travellers, each carrying its own
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  Speaker 1: little rhythm. One has taken one path, the other has
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  Speaker 1: taken another, and when they return, their rhythms no longer
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  Speaker 1: quite agree. This phenomenon is called time dilation, but you
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  Speaker 1: do not need to hold on to the technical name tonight.
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  Speaker 1: You can simply remember the softer idea. Different journeys can
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  Speaker 1: contain different amounts of elapsed time. The universe does not
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  Speaker 1: necessarily give every traveller exactly the same experience of duration.
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  Speaker 1: And this has been tested. It is not only an
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  Speaker 1: idea from a thought experiment. Very accurate clocks can measure
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  Speaker 1: these tiny differences. And systems such as the global positioning
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  Speaker 1: system have to take the effects of relativity into account
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  Speaker 1: to remain accurate. So the quiet clock beside your bed
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  Speaker 1: is still useful. It still gives you a practical sense
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  Speaker 1: of time. Your morning still comes after your night. Your
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  Speaker 1: memories still belong to what you call the past. Your
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  Speaker 1: plans still belong to what you call the future. Nothing
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  Speaker 1: about relativity takes away the gentle usefulness of everyday time.
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  Speaker 1: Instead it asks us to look beneath that familiar experience.
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  Speaker 1: It asks what time is doing when we are no
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  Speaker 1: longer standing still together, when observers are moving differently, when
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  Speaker 1: clocks travel along different paths, and when the distances between
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  Speaker 1: events become enormous. And perhaps this is where the ordinary
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  Speaker 1: word now begins to feel a little less solid, because
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  Speaker 1: if two clocks can follow different journeys and measure different
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  Speaker 1: amounts of time, then perhaps we should pause before imagining
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  Speaker 1: that the entire universe shares one enormous clock. Perhaps there
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  Speaker 1: is no giant clock above the stars. Perhaps there is
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  Speaker 1: only this clock, and another clock, and another, each quietly
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  Speaker 1: recording its own journey. Tick, a little silence, tick. And
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  Speaker 1: while you rest here, there is nothing you need to
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  Speaker 1: decide about any of it. You can simply notice the
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  Speaker 1: strange softness of the idea. Time may be familiar, but
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  Speaker 1: it may not be universal in quite the way it feels.
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  Speaker 1: And if different observers can carry different rhythms of time,
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  Speaker 1: then somewhere in that quiet difference is an even stranger question,
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  Speaker 1: waiting without urgency. When you say the words right now,
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  Speaker 1: what exactly are you pointing to? Perhaps we can stay
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  Speaker 1: with that question for a little while and let it
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  Speaker 1: become quieter. There is a quiet question waiting inside the
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  Speaker 1: one you have just been holding. If time can be
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  Speaker 1: measured differently by observers following different journeys, then what does
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  Speaker 1: it mean for two people to say that something happened
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  Speaker 1: at the same time? For nearby things, the question seems
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  Speaker 1: almost too easy. You are lying in your room. Perhaps
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  Speaker 1: a fan is turning slowly above you. Perhaps somewhere outside,
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  Speaker 1: a car passes through the night. If you and another
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  Speaker 1: person are sitting beside one another, you can usually agree
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  Speaker 1: about what is happening now. You can look at the
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  Speaker 1: fan together. You can hear the same quiet sound. You
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  Speaker 1: can watch the same clock. There is no mystery in it.
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  Speaker 1: Your two experiences of the nearby world can fit together
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  Speaker 1: quite naturally. And so, it is tempting to imagine that
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  Speaker 1: this agreement continues outward, farther and farther, until it covers
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  Speaker 1: the entire universe. You might imagine drawing an enormous invisible
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  Speaker 1: line across space. A line that separates everything happening now
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  Speaker 1: from everything that has already happened and everything that has
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  Speaker 1: not happened yet. On one side, the past. On the
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  Speaker 1: other side, the future. And right in between, one perfectly thin,
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  Speaker 1: universal present. A single cosmic now. But relativity asks you
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  Speaker 1: to be careful with that picture. Because once two observers
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  Speaker 1: are moving differently... They do not necessarily divide distant events
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  Speaker 1: into past, present and future in exactly the same way.
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  Speaker 1: This is called the relativity of simultaneity. The name sounds technical,
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  Speaker 1: but the idea itself can be held very gently. It
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  Speaker 1: simply means that different observers can disagree about which distant
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  Speaker 1: events should be considered to be happening at the same time,
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  Speaker 1: and neither observer has to be making a mistake. Imagine
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  Speaker 1: yourself standing quietly on Earth, looking toward the stars. Far away,
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  Speaker 1: perhaps unimaginably far away, something happens. A light flashes. A
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  Speaker 1: star changes. A distant world turns beneath its own sky.
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  Speaker 1: You ask a simple question. Was that happening now? Your
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  Speaker 1: answer depends on how you define now, across that enormous distance.
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  Speaker 1: Another observer moving relative to you. can make a slightly
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  Speaker 1: different division between what belongs to the past, what belongs
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  Speaker 1: to the present, and what belongs to the future. This
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  Speaker 1: does not mean that the distant event itself becomes confused.
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  Speaker 1: The event is simply an event. What changes is the
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  Speaker 1: way different observers describe its temporal relationship to other events.
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  Speaker 1: And this is where a quiet picture can help. Imagine
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  Speaker 1: an enormous loaf of bread. You do not need to
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  Speaker 1: see it clearly. Perhaps it is sitting somewhere in the
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  Speaker 1: darkness of your imagination, resting peacefully on a wooden table.
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  Speaker 1: The entire loaf represents space-time, the connected structure of space
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  Speaker 1: and time. Now imagine cutting through the loaf. One slice
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  Speaker 1: gives you one way of looking at the whole structure.
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  Speaker 1: Another slice gives you another way. The slices are not
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  Speaker 1: necessarily identical. They can pass through different collections of events.
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  Speaker 1: In the same gentle way, different observers moving relative to
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  Speaker 1: one another can describe different sets of distant events as
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  Speaker 1: belonging to their present. The loaf itself has not changed.
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  Speaker 1: The events have not suddenly moved. Nothing has broken. Only
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  Speaker 1: the way the whole structure is divided into moments has changed.
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  Speaker 1: And this is one of the places where Einstein's theory
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  Speaker 1: becomes quietly strange. Your everyday intuition wants there to be
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  Speaker 1: one answer. It wants the universe to be able to
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  Speaker 1: point to a single moment and say, this is happening everywhere.
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  Speaker 1: But relativity does not give you such a universal answer.
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  Speaker 1: It gives you local agreement, and it gives you relationships
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  Speaker 1: between observers. But it does not provide one great cosmic
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  Speaker 1: clock that every distant observer must obey. You might still
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  Speaker 1: wonder whether this really matters. After all, you are not
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  Speaker 1: racing through space at an enormous speed. You are lying
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  Speaker 1: comfortably in your room. Your body is almost completely still.
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  Speaker 1: Your breathing is slow. Your pillow is beneath your head.
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  Speaker 1: And somewhere beside you, a clock may be quietly measuring
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  Speaker 1: the passing minutes. For everyday life, this is more than enough.
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  Speaker 1: You and the people around you can share a practical present.
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  Speaker 1: But the universe is much larger than the room around you.
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  Speaker 1: When distances become enormous, The word now begins to stretch.
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  Speaker 1: Imagine moving only a tiny amount relative to the earth.
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  Speaker 1: Perhaps you take one small step. To your body, almost
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  Speaker 1: nothing has changed. The floor is still beneath your feet.
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  Speaker 1: The room is still around you. The stars still appear
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  Speaker 1: exactly where they were. Yet when you extend your definition
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  Speaker 1: of now across an immense distance, that tiny change in
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  Speaker 1: motion can correspond to a different assignment of time for
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  Speaker 1: a distant event. The effect is subtle nearby, but distance
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  Speaker 1: magnifies its importance. And this is where Andromeda quietly enters
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  Speaker 1: our story. The Andromeda galaxy is so far away that
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  Speaker 1: its light takes millions of years to reach Earth. You
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  Speaker 1: cannot simply look at it and see what is happening
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  Speaker 1: there at this very instant. The light arriving at your
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  Speaker 1: eyes began its journey long ago. That is one mystery.
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  Speaker 1: But relativity introduces another. Even if you could somehow agree
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  Speaker 1: on a way to describe the distant events in Andromeda,
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  Speaker 1: the exact event you call simultaneous with your present can
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  Speaker 1: depend on your motion relative to another observer. So imagine
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  Speaker 1: you standing quietly beneath the night sky. You look toward
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  Speaker 1: the place where Andromeda lies, far beyond the familiar stars.
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  Speaker 1: Another observer moves past you. Perhaps they are travelling in
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  Speaker 1: a spacecraft. Perhaps they are moving very quickly. You both
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  Speaker 1: carry excellent clocks. You both understand the same laws of physics.
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  Speaker 1: And yet, when you ask which distant event in Andromeda
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  Speaker 1: belongs to your present, your answers can differ. There is
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  Speaker 1: no cosmic referee waiting between the stars to announce which
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  Speaker 1: one of you has chosen the true now. There is
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  Speaker 1: no universal GPS floating above the universe, pointing toward one
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  Speaker 1: privileged present. there are only observers, their motion, their clocks,
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  Speaker 1: and the relationships between events. And somehow, this makes the
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  Speaker 1: universe feel less like a machine with one enormous clock,
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  Speaker 1: and more like a vast structure in which time and
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  Speaker 1: space are quietly connected. You can let that idea rest
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  Speaker 1: for a moment. You do not have to force it
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  Speaker 1: into a conclusion. Your own present is still the moment
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  Speaker 1: you are experiencing. The warmth or coolness of the air
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  Speaker 1: is still here. The sound around you is still here.
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  Speaker 1: Your breathing is still here. Nothing about relativity takes away
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  Speaker 1: the reality of your experience. It simply tells you that
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  Speaker 1: the word now does not necessarily extend across the whole
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  Speaker 1: universe in one universal way. Your now can be local.
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  Speaker 1: Your now can be meaningful. And yet there may be
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  Speaker 1: no single cosmic now shared by everything. The distinction is
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  Speaker 1: small in everyday life. but enormous when you allow your
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  Speaker 1: imagination to travel between the stars. And perhaps that is
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  Speaker 1: the gentlest way to think about relativity. Not as saying
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  Speaker 1: that time is unreal, not as saying that your present
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  Speaker 1: is an illusion, but as quietly reminding you that the
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  Speaker 1: universe does not have to arrange itself according to the
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  Speaker 1: way human intuition first imagined it. You can remain here,
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  Speaker 1: resting beneath the night, while somewhere unimaginably far away, Other
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  Speaker 1: events continue in their own places within the vastness of space-time.
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  Speaker 1: You do not need to know which distant event is
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  Speaker 1: happening right now. For tonight, it is enough to notice
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  Speaker 1: that the question itself has changed. Because once there is
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  Speaker 1: no single answer to the question of distant simultaneity, the
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  Speaker 1: present begins to look less like a universal boundary, and
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  Speaker 1: more like something connected to where you are, how you
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  Speaker 1: are moving, and how you describe the world around you.
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  Speaker 1: And somewhere beyond that quiet boundary of intuition, space and
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  Speaker 1: time begin to fold gently into one another, forming a
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  Speaker 1: larger picture in which moments are not simply passing away,
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  Speaker 1: but can be described as parts of one connected structure.
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  Speaker 1: There is a particular kind of quiet that comes when
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  Speaker 1: you stop looking at the clock. The room is still there,
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  Speaker 1: Your body is still resting where you left it. The
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  Speaker 1: air moves gently around you, perhaps carrying the faint sound
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  Speaker 1: of a fan, or the distant sounds of a city
• 17:43
  Speaker 1: becoming quieter outside. And for a moment, you can simply
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  Speaker 1: be here. Here in this room. Here in this breath.
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  Speaker 1: Here in what you call the present. You do not
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  Speaker 1: usually need to explain what now means. Now is now.
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  Speaker 1: It seems almost impossible to misunderstand. If someone sitting beside
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  Speaker 1: you asks what is happening now, you can look around
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  Speaker 1: and answer without thinking. The room is here. The lights
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  Speaker 1: are here. The sound is here. You are here. And
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  Speaker 1: because nearby events are so easy to share, your mind
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  Speaker 1: naturally extends the idea outward. If you and another person
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  Speaker 1: can agree on what is happening beside you, perhaps you
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  Speaker 1: imagine that two people anywhere in the universe should be
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  Speaker 1: able to agree in exactly the same way. Perhaps there
• 18:35
  Speaker 1: should be one enormous present moment, stretching quietly across space,
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  Speaker 1: touching every star and every planet at once. A universal now.
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  Speaker 1: But the farther your imagination travels, the more delicate that
• 18:49
  Speaker 1: idea becomes. You already saw that two clocks following different
• 18:53
  Speaker 1: journeys can measure different amounts of elapsed time. Now there
• 18:58
  Speaker 1: is another question. Suppose two observers are moving differently. Suppose
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  Speaker 1: both have excellent clocks. Suppose both understand the same laws
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  Speaker 1: of physics. And suppose they ask a very simple question.
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  Speaker 1: Which distant events are happening at the same time as
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  Speaker 1: this one? The answer is no longer necessarily the same
• 19:18
  Speaker 1: for both observers. This is called the relativity of simultaneity.
• 19:24
  Speaker 1: The name sounds heavy, but the idea can be made
• 19:26
  Speaker 1: very soft. It simply means that when events are far apart,
• 19:31
  Speaker 1: different observers can disagree about which of those distant events
• 19:35
  Speaker 1: belong to their present moment. And this disagreement does not
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  Speaker 1: mean that one observer has a broken clock. It does
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  Speaker 1: not mean that one observer is seeing the universe incorrectly.
• 19:45
  Speaker 1: It is part of the structure described by relativity. You
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  Speaker 1: can imagine yourself standing on a quiet platform, watching a
• 19:53
  Speaker 1: train pass through the night. Inside the train, another observer
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  Speaker 1: is moving relative to you. Now imagine that two distant
• 20:01
  Speaker 1: flashes of light occur, one toward one end of the
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  Speaker 1: landscape and another toward the other end. You may describe
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  Speaker 1: those two flashes as happening at the same time. The
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  Speaker 1: observer moving with the train can describe them differently. For
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  Speaker 1: that observer, one event can belong slightly earlier than the other.
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  Speaker 1: The important thing is not that the flashes themselves are changing.
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  Speaker 1: They are not. The events simply happen. What changes is
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  Speaker 1: the way each observer divides distant events into earlier, later
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  Speaker 1: and simultaneous. It is a little like looking at the
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  Speaker 1: same landscape from different angles. The landscape remains. Your viewpoint changes,
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  Speaker 1: and the description that follows from that viewpoint changes with it.
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  Speaker 1: This is where the old picture of a single universal
• 20:51
  Speaker 1: present begins to fade. You can imagine space-time as an
• 20:55
  Speaker 1: enormous loaf of bread. The whole loaf represents the complete
• 20:59
  Speaker 1: structure of space and time. You can cut one slice
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  Speaker 1: through it. That slice gives you one way of gathering
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  Speaker 1: together events that you describe as happening at the same time.
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  Speaker 1: Now imagine another observer, moving differently, making another slice. The
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  Speaker 1: second slice can pass through the loaf at a different angle.
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  Speaker 1: It gathers together a different collection of distant events. Neither
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  Speaker 1: slice has to be the one true slice. Neither observer
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  Speaker 1: has to possess the universe's secret clock. They simply describe
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  Speaker 1: the same space-time from different states of motion. The loaf
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  Speaker 1: is only an image, of course. Space-time is not literally
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  Speaker 1: made of bread, but the image helps you feel something
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  Speaker 1: that equations can make difficult to feel. There is no
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  Speaker 1: requirement in relativity for the universe to provide one enormous
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  Speaker 1: surface labelled now, extending everywhere at once. Instead, the present
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  Speaker 1: you experience is connected to your location and your motion,
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  Speaker 1: And this is a subtle distinction. It does not mean
• 22:02
  Speaker 1: that your present is meaningless. It does not mean that
• 22:06
  Speaker 1: you cannot share a moment with another person. If you
• 22:09
  Speaker 1: are sitting beside someone, resting quietly together, you can still
• 22:14
  Speaker 1: speak of the same local present in an entirely practical way.
• 22:19
  Speaker 1: You can both hear the same sound. You can both
• 22:22
  Speaker 1: watch the same candle flicker. You can both notice the
• 22:25
  Speaker 1: same clock. The strange part appears when you try to
• 22:29
  Speaker 1: stretch that shared present across enormous distances. Then the question
• 22:33
  Speaker 1: becomes much more delicate. What about a galaxy millions of
• 22:37
  Speaker 1: light-years away? What about a planet orbiting a distant star?
• 22:43
  Speaker 1: What about an event taking place in another corner of
• 22:46
  Speaker 1: the universe? What exactly do you mean when you say
• 22:49
  Speaker 1: it is happening now? And this is where you can
• 22:52
  Speaker 1: let your imagination drift toward Andromeda. The Andromeda galaxy is
• 22:57
  Speaker 1: so far away that the light you see from it
• 23:00
  Speaker 1: has been travelling for millions of years. When you look
• 23:03
  Speaker 1: toward it, you are not seeing its immediate appearance. You
• 23:07
  Speaker 1: are receiving ancient light. You are seeing information that began
• 23:11
  Speaker 1: its journey long before you were born, long before the
• 23:14
  Speaker 1: people who lived around you were born, long before many
• 23:18
  Speaker 1: of the ordinary details of human history had taken place.
• 23:22
  Speaker 1: The Andromeda you see is an image carried across an
• 23:25
  Speaker 1: immense distance. But there is another question hiding underneath the light.
• 23:30
  Speaker 1: Imagine that you could somehow describe an event happening in
• 23:33
  Speaker 1: Andromeda at the same time as your present moment. What
• 23:37
  Speaker 1: event would that be? Relativity tells you that the answer
• 23:41
  Speaker 1: can depend on your motion relative to another observer. You
• 23:44
  Speaker 1: might be standing here. Another observer might be moving past you.
• 23:49
  Speaker 1: Both of you can construct your own definition of which
• 23:51
  Speaker 1: distant events are simultaneous with your present, and the two
• 23:55
  Speaker 1: definitions can differ. This is difficult to imagine because your
• 23:59
  Speaker 1: everyday life has trained you to think of now as
• 24:03
  Speaker 1: something universal. But everyday life happens at small distances and
• 24:08
  Speaker 1: relatively gentle speeds. The universe does not have to preserve
• 24:13
  Speaker 1: our everyday intuition on every scale. You can even imagine
• 24:17
  Speaker 1: taking one tiny step Nothing dramatic happens. The floor remains
• 24:22
  Speaker 1: beneath you, the walls remain where they were, the stars
• 24:27
  Speaker 1: seem unchanged. Yet, when you extend your definition of simultaneity
• 24:32
  Speaker 1: across an enormous distance, that tiny change in your motion
• 24:37
  Speaker 1: can alter which distant events you regard as belonging to
• 24:40
  Speaker 1: your present. The difference is almost invisible nearby. But across
• 24:46
  Speaker 1: millions of light-years, the corresponding difference can become enormous. There
• 24:51
  Speaker 1: is no cosmic GPS floating above the stars, pointing toward
• 24:55
  Speaker 1: one privileged universal present. There is no giant clock hidden
• 25:00
  Speaker 1: somewhere beyond the galaxies, quietly declaring which moment is the
• 25:04
  Speaker 1: true moment for everything. There are observers, there are events,
• 25:09
  Speaker 1: there are clocks, there is motion, and there are relationships
• 25:14
  Speaker 1: between all of them. You can allow that thought to
• 25:16
  Speaker 1: become quiet, because none of this takes away the moment
• 25:20
  Speaker 1: you are experiencing right now. Your breathing is still happening.
• 25:24
  Speaker 1: The room is still around you. The surface beneath your
• 25:27
  Speaker 1: body is still supporting you. Your experience of this moment
• 25:31
  Speaker 1: remains your experience. Relativity simply asks you not to assume
• 25:36
  Speaker 1: that this local now must extend across the entire universe
• 25:41
  Speaker 1: as one universal boundary. Your now can be real as
• 25:45
  Speaker 1: an experience. Your now can be useful in everyday life.
• 25:50
  Speaker 1: And still, there may be no single cosmic now shared
• 25:54
  Speaker 1: by every distant observer. That is a small sentence, but
• 25:58
  Speaker 1: it opens a very large space for thought. Because once
• 26:01
  Speaker 1: the universe no longer needs one universal present, past and
• 26:05
  Speaker 1: future begin to look a little different too. Perhaps they
• 26:08
  Speaker 1: are not simply two empty regions waiting on opposite sides
• 26:12
  Speaker 1: of a moving present. Perhaps moments have a deeper relationship
• 26:16
  Speaker 1: with one another. Perhaps what you call the past is
• 26:20
  Speaker 1: not merely something that has vanished. Perhaps what you call
• 26:23
  Speaker 1: the future is not merely something that has yet to arrive.
• 26:27
  Speaker 1: And perhaps, somewhere in the quiet geometry of space-time, there
• 26:32
  Speaker 1: is a larger picture in which every moment has its
• 26:35
  Speaker 1: own place. You do not need to decide whether that
• 26:38
  Speaker 1: picture is true tonight. For now, you can simply rest
• 26:42
  Speaker 1: with the question, What if the universe does not move
• 26:46
  Speaker 1: through one universal present? What if the moments themselves are
• 26:50
  Speaker 1: part of something larger, something quiet and four-dimensional, where the
• 26:55
  Speaker 1: word now describes the place from which you are looking,
• 26:59
  Speaker 1: rather than a single moment shared by everything? And as
• 27:02
  Speaker 1: you remain here, breathing slowly, that larger structure can wait
• 27:07
  Speaker 1: quietly around you, without needing to be understood all at once.
• 27:14
  Speaker 1: There is something peaceful about imagining the universe without asking
• 27:18
  Speaker 1: it to hurry. You can let the room around you
• 27:21
  Speaker 1: become quiet again. Perhaps you are barely moving now, except
• 27:26
  Speaker 1: for the gentle rise and fall of your breathing. The
• 27:29
  Speaker 1: clock may still be somewhere nearby, continuing its patient rhythm,
• 27:34
  Speaker 1: but you do not have to look at it. You
• 27:37
  Speaker 1: already know that another minute will come, and then another,
• 27:41
  Speaker 1: and yet after everything we have been considering, Perhaps you
• 27:44
  Speaker 1: can begin to imagine time in a slightly different way,
• 27:48
  Speaker 1: not as something that must flow everywhere in exactly the
• 27:51
  Speaker 1: same manner, but as something woven together with the places
• 27:55
  Speaker 1: and events of the universe. Space and time are not
• 27:59
  Speaker 1: completely separate backgrounds. They belong to one larger structure. Physicists
• 28:05
  Speaker 1: call this structure space-time. The word sounds technical. but you
• 28:10
  Speaker 1: can think of it simply as the universe described not
• 28:13
  Speaker 1: only by where things happen, but also by when they happen.
• 28:17
  Speaker 1: A star has a place. A planet has a place.
• 28:21
  Speaker 1: You have a place. And each event in your life
• 28:24
  Speaker 1: also has a time. The moment you woke this morning
• 28:27
  Speaker 1: has its place. The moment you began listening has its place.
• 28:31
  Speaker 1: The moment you become sleepy has its place. And the
• 28:34
  Speaker 1: moments still far ahead in your life, whatever they may contain,
• 28:38
  Speaker 1: can also be described as events within space-time. This is
• 28:42
  Speaker 1: where one of the strangest pictures in modern physics begins
• 28:45
  Speaker 1: to appear. It is sometimes called the block universe. The
• 28:50
  Speaker 1: phrase can sound as though the universe were a giant
• 28:53
  Speaker 1: frozen object, sitting somewhere in an enormous darkness. But you
• 28:58
  Speaker 1: do not need to imagine a literal block. Instead, return
• 29:02
  Speaker 1: to the quiet loaf of bread. Imagine the whole loaf
• 29:05
  Speaker 1: resting peacefully on a table. The loaf represents the entire
• 29:09
  Speaker 1: structure of space-time. A slice through the loaf represents one
• 29:14
  Speaker 1: particular way of describing what is happening at a certain moment.
• 29:18
  Speaker 1: And another slice represents another moment. Your everyday experience makes
• 29:22
  Speaker 1: these slices feel very different. One slice is what you
• 29:26
  Speaker 1: call the past. Another is what you call the present.
• 29:30
  Speaker 1: Another is what you call the future. From inside your experience,
• 29:34
  Speaker 1: you seem to move from one slice to another. Yesterday
• 29:38
  Speaker 1: becomes today. Today becomes tomorrow. A moment disappears behind you,
• 29:43
  Speaker 1: while another moment seems to approach from somewhere ahead. But
• 29:47
  Speaker 1: the block universe picture asks you to imagine something different.
• 29:52
  Speaker 1: What if the slices do not need to disappear? What
• 29:55
  Speaker 1: if the past is not destroyed simply because it is
• 29:58
  Speaker 1: no longer your present? What if the future does not
• 30:01
  Speaker 1: need to be created only at the moment you reach it?
• 30:05
  Speaker 1: Within this particular interpretation, the different moments can be thought
• 30:09
  Speaker 1: of as different parts of one four-dimensional structure. This is
• 30:13
  Speaker 1: an interpretation of what relativity suggests about space-time, rather than
• 30:18
  Speaker 1: a simple experiment proving that the future literally exists. That
• 30:23
  Speaker 1: distinction is important. Relativity gives us the structure. The block
• 30:28
  Speaker 1: universe is one way of understanding what that structure might
• 30:31
  Speaker 1: mean for the nature of time. And there are other possibilities.
• 30:35
  Speaker 1: Some philosophers defend a view called presentism. In presentism, only
• 30:41
  Speaker 1: the present truly exists. The past has existed, but no
• 30:46
  Speaker 1: longer exists. The future has not yet arrived, and therefore
• 30:50
  Speaker 1: does not exist yet. Another possibility is sometimes called the
• 30:55
  Speaker 1: growing block view. In that picture, the past and present exist,
• 31:01
  Speaker 1: while the future has not yet become part of reality.
• 31:04
  Speaker 1: And then there is eternalism, the philosophical view most closely
• 31:08
  Speaker 1: associated with the block universe picture, in which past, present
• 31:13
  Speaker 1: and future can all be regarded as existing within the
• 31:17
  Speaker 1: larger temporal structure. You do not need to choose between
• 31:21
  Speaker 1: these ideas tonight. There is no examination waiting for you.
• 31:25
  Speaker 1: There is no correct answer you need to discover before
• 31:28
  Speaker 1: you can sleep. It is enough to notice how differently
• 31:32
  Speaker 1: each picture changes the feeling of time. In the everyday picture,
• 31:37
  Speaker 1: the present seems special. It is the only place where
• 31:40
  Speaker 1: you are actually standing. The past feels like something behind you.
• 31:45
  Speaker 1: The future feels like something ahead. But in the block
• 31:49
  Speaker 1: universe picture, your present is not necessarily the only part
• 31:53
  Speaker 1: of reality. It is simply the part you are currently experiencing.
• 31:58
  Speaker 1: Imagine a quiet book resting on a table. Every page
• 32:02
  Speaker 1: belongs to the same book. The first page does not
• 32:05
  Speaker 1: stop being part of the book when you reach the middle.
• 32:09
  Speaker 1: The last page does not need to rush toward you.
• 32:12
  Speaker 1: The book, considered as a whole, contains all of its pages.
• 32:16
  Speaker 1: Yet if you are reading it, you experience one page
• 32:19
  Speaker 1: at a time. You remember the pages behind you. You
• 32:23
  Speaker 1: cannot yet experience the pages ahead. Your experience has an order.
• 32:28
  Speaker 1: The book does not necessarily need to move. This metaphor
• 32:32
  Speaker 1: is only a way of approaching the idea, not a
• 32:35
  Speaker 1: literal description of consciousness or space-time. And perhaps that is
• 32:39
  Speaker 1: one reason the block universe feels so strange. Your mind
• 32:43
  Speaker 1: expects time to move. You expect the present to travel forward.
• 32:48
  Speaker 1: But the block universe itself does not need to move
• 32:50
  Speaker 1: from one moment to another. There is no second universe
• 32:54
  Speaker 1: outside the block pushing it forward. There is no invisible
• 32:58
  Speaker 1: hand turning the pages. There is simply the structure, if
• 33:02
  Speaker 1: this interpretation is correct, containing relationships between events. And then
• 33:07
  Speaker 1: your experience enters the picture. You remember what has happened.
• 33:11
  Speaker 1: You anticipate what might happen. You experience this particular moment.
• 33:17
  Speaker 1: Memory points backward. Expectation points forward. Awareness seems to remain
• 33:22
  Speaker 1: here and from inside that experience time feels as though
• 33:26
  Speaker 1: it is flowing. But perhaps the feeling of flow is
• 33:30
  Speaker 1: not the same thing as a physical object flowing through
• 33:33
  Speaker 1: the universe. This does not make the feeling unreal. When
• 33:36
  Speaker 1: you remember an old afternoon the memory is real as
• 33:40
  Speaker 1: a memory. When you imagine tomorrow morning the anticipation is
• 33:44
  Speaker 1: real as an experience. When you notice the quiet air
• 33:48
  Speaker 1: around you this present moment is real. as something you
• 33:52
  Speaker 1: are experiencing. The question is simply whether the universe itself
• 33:56
  Speaker 1: contains a universal moving present, separate from all the events
• 34:01
  Speaker 1: that make up space-time. Relativity does not give us such
• 34:04
  Speaker 1: a universal present. And the block universe interpretation goes one
• 34:09
  Speaker 1: step further, suggesting that what we call past, present and
• 34:13
  Speaker 1: future may be better understood as different temporal locations within
• 34:17
  Speaker 1: one larger structure. You can let the loaf become quiet again.
• 34:22
  Speaker 1: Imagine its many slices resting together. You do not need
• 34:26
  Speaker 1: to travel through them tonight. You do not need to
• 34:28
  Speaker 1: know what lies in every slice. You can simply remain
• 34:32
  Speaker 1: where you are. Here. In this room. In this particular moment.
• 34:37
  Speaker 1: And perhaps there is something strangely comforting in realising that
• 34:40
  Speaker 1: the universe does not need to rush in order for
• 34:43
  Speaker 1: moments to exist. A moment can simply be a moment.
• 34:48
  Speaker 1: A memory can simply be a memory. A possibility can
• 34:51
  Speaker 1: simply be something you have not yet experienced. And somewhere
• 34:55
  Speaker 1: in the vast structure of space-time, if the block universe
• 34:58
  Speaker 1: picture happens to describe reality well, all of these moments
• 35:03
  Speaker 1: may have their own places, connected quietly across the dimensions
• 35:07
  Speaker 1: of existence. The idea does not need to become frightening.
• 35:11
  Speaker 1: It does not need to become dramatic. You can let
• 35:14
  Speaker 1: it remain as soft as the image of a loaf
• 35:17
  Speaker 1: resting untouched in the darkness. One slice is where you are.
• 35:22
  Speaker 1: Other slices belong to other times. And perhaps, before we
• 35:27
  Speaker 1: ask what this means for the future, it is worth
• 35:30
  Speaker 1: looking upward again, toward the stars, because the night sky
• 35:34
  Speaker 1: already gives you a simple experience of many different moments
• 35:38
  Speaker 1: appearing together. Every distant point of light carries an older story.
• 35:43
  Speaker 1: And as you look at it, you are receiving a
• 35:46
  Speaker 1: message that began its journey long before this quiet moment began.
• 35:53
  Speaker 1: You can let your attention drift upward now, away from
• 35:56
  Speaker 1: the quiet room, away from the clock, and toward the
• 35:59
  Speaker 1: darkness above you. There may be no stars visible from
• 36:03
  Speaker 1: where you are. Perhaps there are buildings outside, or clouds,
• 36:08
  Speaker 1: or simply the soft glow of a sleeping city. It
• 36:11
  Speaker 1: does not matter. You can imagine the night sky anyway,
• 36:14
  Speaker 1: stretching quietly above the earth, filled with points of light
• 36:18
  Speaker 1: that seem almost motionless. A star appears to be simply there,
• 36:23
  Speaker 1: a small light, a distant presence, something shining in the darkness.
• 36:29
  Speaker 1: But when you look at a star, you are not
• 36:31
  Speaker 1: seeing it as it is at this exact moment. You
• 36:34
  Speaker 1: are receiving light that has travelled across space, and light
• 36:38
  Speaker 1: takes time to travel. This means that every distant star
• 36:43
  Speaker 1: you see is also a glimpse into history. The farther
• 36:47
  Speaker 1: away the star is, the older the light can be
• 36:50
  Speaker 1: by the time it reaches you. You do not need
• 36:53
  Speaker 1: to calculate the distance. You do not need to imagine
• 36:56
  Speaker 1: enormous numbers. You can simply picture a small message leaving
• 37:00
  Speaker 1: a distant star, travelling quietly through darkness, crossing immense stretches
• 37:06
  Speaker 1: of space, and finally arriving at your eyes. The message
• 37:10
  Speaker 1: may have been travelling for years, or centuries, or much longer,
• 37:15
  Speaker 1: and when it finally reaches you, you see the star
• 37:19
  Speaker 1: as it was when that light began its journey. This
• 37:22
  Speaker 1: is one of the gentlest ways to understand why looking
• 37:25
  Speaker 1: outward through space also means looking backward through time. The
• 37:30
  Speaker 1: night sky is filled with old light. You are surrounded
• 37:34
  Speaker 1: by ancient messages. And yet, there is an important distinction here.
• 37:39
  Speaker 1: Seeing the past is not quite the same thing as
• 37:42
  Speaker 1: defining the past, present and future for a distant place.
• 37:47
  Speaker 1: The light arriving from a star tells you about an
• 37:50
  Speaker 1: earlier event. It does not directly tell you which event
• 37:54
  Speaker 1: is happening at that star at the same time as
• 37:56
  Speaker 1: your present moment. Those are two different questions. One question is,
• 38:02
  Speaker 1: when did this light leave? The other is, what distant
• 38:06
  Speaker 1: event would count as happening now according to a particular observer.
• 38:11
  Speaker 1: The first question can be answered by following the journey
• 38:14
  Speaker 1: of light. The second depends on how simultaneity is defined
• 38:19
  Speaker 1: within relativity. You can let those two ideas rest beside
• 38:23
  Speaker 1: one another, quietly. Light carries information from the past. Relativity
• 38:28
  Speaker 1: tells you that there is no single universal way for
• 38:32
  Speaker 1: every observer to divide distant events into one shared present. Together,
• 38:37
  Speaker 1: They make the night sky feel a little different. Consider Polaris,
• 38:42
  Speaker 1: the North Star. When you look toward it, the light
• 38:45
  Speaker 1: reaching you has travelled for more than four centuries. So
• 38:49
  Speaker 1: the Polaris you see is not a live picture in
• 38:52
  Speaker 1: the ordinary sense. It is an old image carried across space.
• 38:57
  Speaker 1: You are receiving light that began its journey when human
• 39:01
  Speaker 1: history looked very different. People were living lives that are
• 39:05
  Speaker 1: now part of the distant past. Cities looked different. Languages
• 39:10
  Speaker 1: sounded different. The world itself had another rhythm. And somewhere
• 39:14
  Speaker 1: far away, light was beginning a journey that would eventually
• 39:18
  Speaker 1: reach you. You can imagine that journey without making it dramatic.
• 39:23
  Speaker 1: A tiny packet of light leaves the star. It travels.
• 39:27
  Speaker 1: The universe remains quiet. The light continues. And much later,
• 39:32
  Speaker 1: it reaches your eyes. That is all. A simple journey
• 39:36
  Speaker 1: through darkness. And because the universe is so large, you
• 39:40
  Speaker 1: can receive many different ages of light at the same time.
• 39:44
  Speaker 1: One star may show you light that is relatively young,
• 39:48
  Speaker 1: Another may show you light that began its journey centuries ago.
• 39:51
  Speaker 1: A distant galaxy may show you an image from millions
• 39:55
  Speaker 1: or billions of years in the past. Your eyes can
• 39:59
  Speaker 1: receive all of these messages together. The present moment in
• 40:02
  Speaker 1: your room can therefore contain light from many different histories.
• 40:07
  Speaker 1: You are resting here now, while photons from distant places
• 40:11
  Speaker 1: arrive carrying information about what those places were like long ago.
• 40:16
  Speaker 1: The room is quiet. The stars are distant, and time
• 40:20
  Speaker 1: is layered into what you see. Even our own galaxy
• 40:24
  Speaker 1: can be thought of this way. When you look toward
• 40:27
  Speaker 1: the Milky Way, you are not receiving one perfectly synchronised
• 40:31
  Speaker 1: image of the entire galaxy. You are receiving light from
• 40:34
  Speaker 1: stars at different distances. Some light has travelled less, some
• 40:39
  Speaker 1: has travelled more. So the galaxy you see contains many
• 40:43
  Speaker 1: different historical moments layered together in your view. It is
• 40:47
  Speaker 1: almost as though the darkness above you were filled with
• 40:50
  Speaker 1: overlapping memories. Not memories in the human sense. Not conscious memories.
• 40:56
  Speaker 1: Simply information carried by light. A star shines. Its light travels.
• 41:02
  Speaker 1: The light reaches you. And suddenly, something that happened long
• 41:06
  Speaker 1: ago becomes part of your present experience. You can let
• 41:10
  Speaker 1: that thought become very soft, because there is something reassuring
• 41:14
  Speaker 1: about the simplicity of it. The universe does not need
• 41:18
  Speaker 1: to hurry. Light does not need to hurry. A distant
• 41:22
  Speaker 1: star does not need to know that you are looking.
• 41:24
  Speaker 1: Its light simply travels across the space between you. And
• 41:28
  Speaker 1: when it arrives, you receive a small piece of its history.
• 41:33
  Speaker 1: This also helps explain why astronomers can learn about the
• 41:36
  Speaker 1: early universe by looking very far away. Very distant objects
• 41:41
  Speaker 1: are seen through light that has been travelling for enormous
• 41:44
  Speaker 1: periods of time. The farther the light has travelled, the
• 41:48
  Speaker 1: farther back into cosmic history your observations can reach. You
• 41:53
  Speaker 1: are not literally travelling into the past. You are receiving
• 41:56
  Speaker 1: old information in the present. That distinction is gentle but important.
• 42:02
  Speaker 1: When you look at a distant galaxy, you are not
• 42:05
  Speaker 1: opening a window through which you can step backward in time.
• 42:09
  Speaker 1: You are simply allowing ancient light to arrive. The past
• 42:13
  Speaker 1: has not physically returned. A message from the past has
• 42:17
  Speaker 1: reached you, and perhaps this is one of the quietest
• 42:20
  Speaker 1: ways to think about time. You are always surrounded by
• 42:23
  Speaker 1: information from moments that are no longer happening here. The
• 42:27
  Speaker 1: sound you hear has travelled through the room. The light
• 42:31
  Speaker 1: around you has reached your eyes. The distant stars send
• 42:34
  Speaker 1: their ancient signals across space. Your senses are constantly receiving
• 42:39
  Speaker 1: traces of events that began somewhere else, sometime before. Even now,
• 42:45
  Speaker 1: As you rest, the universe is touching you through delayed information.
• 42:49
  Speaker 1: Nothing needs to be forced. Nothing needs to be solved.
• 42:53
  Speaker 1: You can simply breathe. And somewhere far above, beyond the atmosphere,
• 42:58
  Speaker 1: light continues its patient journey. Some of it began only
• 43:02
  Speaker 1: a little while ago. Some of it began before your
• 43:05
  Speaker 1: grandparents were born. Some began before human civilization took its
• 43:10
  Speaker 1: familiar forms. Some began before the earth looked anything like
• 43:14
  Speaker 1: the world you know. All of it arrives as light.
• 43:18
  Speaker 1: All of it becomes part of what you can see.
• 43:21
  Speaker 1: And perhaps, when you look at the night sky this way,
• 43:24
  Speaker 1: the stars no longer seem like objects simply hanging in
• 43:27
  Speaker 1: the darkness. They become quiet messengers, not speaking, not calling,
• 43:33
  Speaker 1: simply arriving. And beneath them, you remain here, in your
• 43:38
  Speaker 1: small local present, listening to the slow rhythm of your breathing.
• 43:42
  Speaker 1: You do not need to know exactly what is happening
• 43:45
  Speaker 1: on every distant world right now. There is no need
• 43:48
  Speaker 1: for a cosmic clock. There is only this moment around you,
• 43:52
  Speaker 1: and the ancient light arriving from everywhere beyond it. Perhaps
• 43:57
  Speaker 1: that is enough for tonight, and as you continue resting,
• 44:01
  Speaker 1: there is another quiet possibility waiting in the distance, because
• 44:05
  Speaker 1: if the meaning of now can change with motion, then
• 44:08
  Speaker 1: even something as small as a gentle change in your
• 44:11
  Speaker 1: movement can alter which distant moment you would call simultaneous
• 44:15
  Speaker 1: with your own. You can remain exactly where you are
• 44:21
  Speaker 1: for a little while. There is no need to imagine
• 44:24
  Speaker 1: yourself travelling through the universe. No need to leave the
• 44:28
  Speaker 1: quiet room. You can simply feel the surface beneath you.
• 44:33
  Speaker 1: Notice the slow rhythm of your breathing. and allow the
• 44:36
  Speaker 1: darkness around you to become softer. And yet, while you
• 44:40
  Speaker 1: remain here, the Earth is moving, very slowly from the
• 44:44
  Speaker 1: perspective of your senses, but constantly, quietly, the planet turns
• 44:49
  Speaker 1: beneath you, the Earth travels around the Sun, the Sun
• 44:53
  Speaker 1: travels with the rest of the solar system through the
• 44:56
  Speaker 1: Milky Way, and the Milky Way itself is moving through
• 44:59
  Speaker 1: the larger universe. You do not feel these motions. There
• 45:03
  Speaker 1: is no cosmic wind brushing against your skin. No gentle
• 45:07
  Speaker 1: vibration announces that the earth has travelled another enormous distance.
• 45:12
  Speaker 1: Everything around you moves together, so your body experiences this
• 45:16
  Speaker 1: shared motion as stillness. And this gives you another quiet
• 45:20
  Speaker 1: lesson about motion. You are not absolutely still, but you
• 45:24
  Speaker 1: are also not absolutely moving. Those words only become meaningful
• 45:28
  Speaker 1: when you say what you are moving relative to. You
• 45:32
  Speaker 1: can be resting relative to the floor. You can be
• 45:35
  Speaker 1: moving relative to the sun. You can be moving differently
• 45:39
  Speaker 1: relative to another star. There is no single cosmic platform
• 45:43
  Speaker 1: floating outside the universe from which everything can be measured
• 45:47
  Speaker 1: against one final state of rest. There is no universal
• 45:51
  Speaker 1: sign saying, here is the true stationary position. You are
• 45:56
  Speaker 1: simply part of a moving universe. And the same idea
• 46:00
  Speaker 1: returns us gently to the question of distant time. Imagine
• 46:04
  Speaker 1: that you are standing on Earth, perhaps near a window,
• 46:07
  Speaker 1: looking toward the distant Andromeda galaxy. You are not moving quickly.
• 46:12
  Speaker 1: You might take one small step, perhaps just enough to
• 46:15
  Speaker 1: shift your position slightly. Nothing around you seems different. The
• 46:20
  Speaker 1: room does not change. The stars do not visibly move.
• 46:24
  Speaker 1: Andromeda remains a faint and distant presence, Your local experience
• 46:29
  Speaker 1: of time remains essentially the same, yet relativity gives you
• 46:33
  Speaker 1: a strange little thought to hold quietly. When you change
• 46:37
  Speaker 1: your motion, even slightly, the way you divide distant events
• 46:41
  Speaker 1: into simultaneous moments can change. That does not mean Andromeda
• 46:45
  Speaker 1: suddenly changes. Nothing there receives a signal from your step.
• 46:50
  Speaker 1: Nothing in that distant galaxy jumps forward or backward because
• 46:54
  Speaker 1: you moved across your room. the events themselves remain where
• 46:58
  Speaker 1: they are. What changes is your frame of reference, and
• 47:02
  Speaker 1: therefore your description of which distant event belongs to the
• 47:05
  Speaker 1: same present as the event happening here. For nearby objects,
• 47:10
  Speaker 1: the difference is far too small to notice in ordinary life,
• 47:14
  Speaker 1: but when the distance becomes enormous, the difference can become
• 47:18
  Speaker 1: much more significant. This is one of those ideas that
• 47:21
  Speaker 1: becomes easier when you do not try to picture it
• 47:24
  Speaker 1: too sharply. You can simply imagine a very large loaf
• 47:28
  Speaker 1: of bread. Your local moment is one small slice. Far away,
• 47:33
  Speaker 1: in another part of the loaf, there are countless other events.
• 47:37
  Speaker 1: Your way of slicing through the loaf depends partly on
• 47:41
  Speaker 1: how you are moving. Change the motion, and the slice
• 47:45
  Speaker 1: changes slightly. The bread itself has not changed. The distant
• 47:49
  Speaker 1: events have not changed. Only the way you group those
• 47:52
  Speaker 1: events together as happening at the same time has changed.
• 47:57
  Speaker 1: And perhaps that is enough. You do not need to
• 48:00
  Speaker 1: know exactly where the slice passes. You only need to
• 48:03
  Speaker 1: notice that there is no requirement for every observer to
• 48:06
  Speaker 1: make the same distant slice. This is why a universal
• 48:10
  Speaker 1: present becomes so difficult to preserve within relativity. If there
• 48:15
  Speaker 1: were one absolute now, independent of motion, then every observer
• 48:20
  Speaker 1: should eventually be able to discover that same cosmic moment.
• 48:24
  Speaker 1: But relativity does not provide such a universal clock. Instead,
• 48:29
  Speaker 1: the relationship between observers matters. Their motion matters. Their measurements
• 48:34
  Speaker 1: of time matter. And the way they assign simultaneity to
• 48:39
  Speaker 1: distant events can differ. You can return to Andromeda once more.
• 48:44
  Speaker 1: It is more than two million light-years away. The light
• 48:48
  Speaker 1: arriving from it began its journey millions of years ago.
• 48:52
  Speaker 1: So when you see the galaxy, you are seeing an
• 48:54
  Speaker 1: ancient image. But suppose you ask a different question, not
• 48:58
  Speaker 1: what am I seeing, but what event in Andromeda is
• 49:02
  Speaker 1: happening now, at the same time as my present moment?
• 49:06
  Speaker 1: That question is much more delicate. There is no simple
• 49:10
  Speaker 1: answer that belongs to every observer in the universe. An
• 49:14
  Speaker 1: observer moving relative to you can construct a different set
• 49:17
  Speaker 1: of distant events that they regard as simultaneous with their
• 49:21
  Speaker 1: own present. The difference is not something you could feel
• 49:24
  Speaker 1: in your body. It is not a sensation. It is
• 49:27
  Speaker 1: a consequence of how space and time are related in relativity.
• 49:32
  Speaker 1: And perhaps you can think of this as a reminder
• 49:35
  Speaker 1: that the universe does not need to match the scale
• 49:37
  Speaker 1: of human intuition. Your mind evolved to understand nearby objects.
• 49:43
  Speaker 1: A person beside you. A tree across the street. The
• 49:47
  Speaker 1: changing light of morning and evening. The passage of days.
• 49:51
  Speaker 1: For these experiences, the idea of one shared present works beautifully.
• 49:56
  Speaker 1: If you and another person sit together beneath the same
• 49:59
  Speaker 1: quiet sky, there is no practical need to argue about
• 50:03
  Speaker 1: whose present is real. You share the same local surroundings.
• 50:08
  Speaker 1: You share the same ordinary rhythm. You can hear the
• 50:11
  Speaker 1: same rain. You can watch the same light fade from
• 50:14
  Speaker 1: the room. You can both say, quite naturally, this is
• 50:18
  Speaker 1: happening now. Relativity does not take that away. It simply
• 50:23
  Speaker 1: tells you that the word now becomes more subtle when
• 50:27
  Speaker 1: you extend it across vast distances and different states of motion.
• 50:32
  Speaker 1: And this subtlety leads to something even quieter. Perhaps time
• 50:37
  Speaker 1: is not a giant river flowing through the universe at
• 50:40
  Speaker 1: one universal speed. Perhaps there is no cosmic current carrying
• 50:45
  Speaker 1: every star, every planet, and every person from one shared
• 50:49
  Speaker 1: present toward another. Instead, each observer has their own path
• 50:54
  Speaker 1: through spacetime. Each clock follows its own journey. Each event
• 50:59
  Speaker 1: has its own location in the larger structure. And when
• 51:02
  Speaker 1: observers compare their measurements... The universe asks them to account
• 51:07
  Speaker 1: for how they moved. You can let that thought settle.
• 51:10
  Speaker 1: Your body remains still against the bed. The earth continues turning.
• 51:15
  Speaker 1: The planet continues travelling around the sun. The solar system
• 51:19
  Speaker 1: continues its journey through the galaxy. And somewhere far beyond
• 51:23
  Speaker 1: your room, Andromeda continues its own immense dance through space.
• 51:28
  Speaker 1: Nothing needs to hurry. Nothing needs to announce where the
• 51:32
  Speaker 1: true present is. You can simply remain here. And perhaps
• 51:36
  Speaker 1: this is one of the most peaceful consequences of the
• 51:39
  Speaker 1: whole idea. You do not need to locate a universal now.
• 51:44
  Speaker 1: You do not need to know what every distant star
• 51:46
  Speaker 1: is doing at this exact moment. Your local moment is enough.
• 51:51
  Speaker 1: Your breathing is enough. The quiet room is enough. The
• 51:55
  Speaker 1: universe can remain vast and unresolved around you. And as
• 51:59
  Speaker 1: you rest here, The distinction between space and time becomes
• 52:03
  Speaker 1: softer still, because perhaps the two are not separate stages
• 52:07
  Speaker 1: after all, but parts of one larger landscape through which
• 52:12
  Speaker 1: every event has its own quiet place. You can let
• 52:17
  Speaker 1: yourself become comfortable again. There is nothing you need to
• 52:21
  Speaker 1: decide tonight, nothing you need to prove, nothing you need
• 52:25
  Speaker 1: to solve before you can rest. You can simply remain here,
• 52:29
  Speaker 1: listening to the quiet rhythm of your breathing, while the
• 52:33
  Speaker 1: idea of space-time rests gently in the background. A universe
• 52:38
  Speaker 1: made of moments, a universe in which your present may
• 52:41
  Speaker 1: be local rather than universal, a universe in which different
• 52:45
  Speaker 1: observers can describe distant simultaneity differently. And now, very softly,
• 52:51
  Speaker 1: another question appears. If the past, present and future are
• 52:56
  Speaker 1: can all be described as parts of one larger spacetime structure.
• 53:00
  Speaker 1: What does that mean for the future? Does it mean
• 53:03
  Speaker 1: that the future is already determined? Does it mean that
• 53:06
  Speaker 1: everything you will ever do is already fixed somewhere in
• 53:10
  Speaker 1: the structure of spacetime? Or does it mean something quieter
• 53:14
  Speaker 1: and more complicated? You do not need to answer. In fact,
• 53:19
  Speaker 1: science does not give you a simple final answer here.
• 53:22
  Speaker 1: The block universe picture is raises the question of determinism.
• 53:26
  Speaker 1: But the picture itself does not automatically prove that every
• 53:30
  Speaker 1: detail of your life is predetermined. That distinction is important.
• 53:35
  Speaker 1: The idea is tempting. If you imagine your entire life
• 53:39
  Speaker 1: as a complete structure, with childhood, adulthood, old age, memories, conversations,
• 53:46
  Speaker 1: quiet mornings, difficult evenings, and ordinary afternoons all having their
• 53:51
  Speaker 1: own places in space-time, it can feel as though the
• 53:54
  Speaker 1: story must already be written. The source material that inspired
• 53:58
  Speaker 1: this journey describes the block universe idea in exactly this direction,
• 54:04
  Speaker 1: asking whether a future that has a place in spacetime
• 54:07
  Speaker 1: would mean that everything is predetermined, while also noting that
• 54:11
  Speaker 1: quantum mechanics introduces a different possibility involving genuine randomness. But
• 54:18
  Speaker 1: you can hold the thought more gently. Imagine a book
• 54:21
  Speaker 1: resting quietly on a table. Its pages belong to the
• 54:25
  Speaker 1: same book. The beginning is there, the middle is there,
• 54:29
  Speaker 1: the ending is there. If you are reading it, however,
• 54:33
  Speaker 1: you experience the story one page at a time. You
• 54:36
  Speaker 1: remember what you have already read. You are experiencing the
• 54:40
  Speaker 1: page beneath your attention, and the pages ahead remain unknown
• 54:45
  Speaker 1: to you. This does not tell you exactly how consciousness works.
• 54:49
  Speaker 1: It is simply a soft way to imagine the difference
• 54:52
  Speaker 1: between the structure of something and the experience of moving
• 54:56
  Speaker 1: through it. Your experience has sequence. You remember one moment,
• 55:01
  Speaker 1: then experience another. You anticipate what might happen later. You
• 55:05
  Speaker 1: notice one breath, and then another. You hear one sound fade,
• 55:10
  Speaker 1: and then another arrive. From inside your own awareness, life
• 55:15
  Speaker 1: has an unmistakable direction. Past. Present. future. Yet a block
• 55:21
  Speaker 1: universe interpretation does not necessarily require the structure itself to
• 55:26
  Speaker 1: be flowing. The whole arrangement can simply contain relationships between events.
• 55:32
  Speaker 1: And this brings you to one of the oldest questions
• 55:34
  Speaker 1: hidden inside the modern physics of time. Is the flow
• 55:38
  Speaker 1: of time something the universe itself does? Or is the
• 55:42
  Speaker 1: flow something your consciousness experiences? The source material describes this
• 55:47
  Speaker 1: feeling of moving from past to future as potentially arising
• 55:52
  Speaker 1: from the sequential way consciousness experiences moments, rather than from
• 55:57
  Speaker 1: a literal cosmic flow through time. That is a philosophical interpretation,
• 56:02
  Speaker 1: not an established experimental fact. And perhaps you can let
• 56:06
  Speaker 1: the distinction remain open. You do not need to imagine
• 56:10
  Speaker 1: that your experience is false. When you feel time passing,
• 56:14
  Speaker 1: You really are experiencing something. When an old memory appears,
• 56:19
  Speaker 1: you really are remembering. When you become aware of the
• 56:23
  Speaker 1: quiet room around you, you really are experiencing this moment.
• 56:28
  Speaker 1: The question is whether the universe itself contains an additional
• 56:31
  Speaker 1: moving substance called time, carrying reality from one moment into another.
• 56:37
  Speaker 1: Relativity does not require such a substance. It describes events, clocks, motion.
• 56:44
  Speaker 1: and relationships between them. And then quantum physics enters the conversation.
• 56:49
  Speaker 1: At the smallest scales, nature does not always behave like
• 56:53
  Speaker 1: the completely predictable clockwork imagined in some older pictures of physics.
• 56:58
  Speaker 1: Quantum theory contains probabilities and forms of uncertainty that have
• 57:02
  Speaker 1: led physicists and philosophers to ask whether genuine randomness exists
• 57:07
  Speaker 1: in nature. The source material presents this as an unresolved debate.
• 57:12
  Speaker 1: with some views treating the block universe as compatible with
• 57:15
  Speaker 1: a predetermined history, while other views point toward quantum randomness.
• 57:21
  Speaker 1: You do not need to follow that debate tonight. You
• 57:24
  Speaker 1: can simply notice the quiet tension between the two possibilities.
• 57:29
  Speaker 1: One possibility imagines a universe whose events are fixed within
• 57:33
  Speaker 1: a complete structure. Another allows that some aspects of nature
• 57:38
  Speaker 1: may not be determined in advance, in the way a
• 57:41
  Speaker 1: perfectly predictable clock would be. And even then, the word
• 57:45
  Speaker 1: random does not automatically answer the question of free will.
• 57:50
  Speaker 1: Randomness and freedom are not necessarily the same thing. A
• 57:54
  Speaker 1: decision being unpredictable would not, by itself, explain why you
• 57:59
  Speaker 1: experience yourself as the person making it. So the mystery remains.
• 58:04
  Speaker 1: Perhaps that is appropriate. Some questions become more beautiful when
• 58:08
  Speaker 1: they remain open. You can let the universe remain larger
• 58:12
  Speaker 1: than your explanations. After all, you are lying here on
• 58:16
  Speaker 1: one small planet, beneath a sky filled with light that
• 58:20
  Speaker 1: has travelled for years, centuries, and millions of years. You
• 58:26
  Speaker 1: are one local observer. Your present is real to your experience.
• 58:31
  Speaker 1: Your memories connect you to earlier moments. Your expectations reach
• 58:35
  Speaker 1: toward moments you have not yet experienced. And somewhere within
• 58:39
  Speaker 1: all of this is the strange possibility that your entire
• 58:43
  Speaker 1: life can be described as one extended history in space-time.
• 58:48
  Speaker 1: Not as a movie being played somewhere outside you. Not
• 58:51
  Speaker 1: as a script that you can read in advance. Not
• 58:54
  Speaker 1: as a claim that every decision has been proven to
• 58:57
  Speaker 1: be predetermined. Simply as a way of describing the total
• 59:01
  Speaker 1: collection of events that make up your existence. The first
• 59:04
  Speaker 1: time you opened your eyes. The first voice you recognised.
• 59:09
  Speaker 1: the places you have lived. The people you have met.
• 59:12
  Speaker 1: The ordinary days that seemed unimportant while they were happening.
• 59:16
  Speaker 1: The quiet moments you may have forgotten. The moments you
• 59:20
  Speaker 1: will remember for years. All of these can be described
• 59:24
  Speaker 1: as events with their own locations in space-time, And if
• 59:28
  Speaker 1: the block universe interpretation is right, they are not necessarily
• 59:32
  Speaker 1: erased when you move beyond them. They remain part of
• 59:35
  Speaker 1: the structure. The past does not need to be physically
• 59:39
  Speaker 1: present in your room for it to remain part of
• 59:41
  Speaker 1: your history. A childhood afternoon does not need to happen
• 59:44
  Speaker 1: again for it to have happened. A forgotten conversation does
• 59:48
  Speaker 1: not need to return for it to belong to your life.
• 59:51
  Speaker 1: A future event, if eternalism is the correct interpretation... would
• 59:56
  Speaker 1: have its own place in the structure, even though you
• 59:59
  Speaker 1: have not yet experienced it. And still, from inside your life,
• 1:00:04
  Speaker 1: you encounter only one moment at a time. That is
• 1:00:08
  Speaker 1: perhaps the quietest mystery. The structure may be larger than
• 1:00:12
  Speaker 1: your experience. Your experience remains sequential. You do not need
• 1:00:17
  Speaker 1: to see the whole landscape at once. You only need
• 1:00:20
  Speaker 1: to rest where you are. The question of whether the
• 1:00:23
  Speaker 1: future is fixed can remain somewhere far away, beyond the
• 1:00:27
  Speaker 1: edge of tonight's thoughts. You are safe. There is nothing
• 1:00:31
  Speaker 1: to do. You can simply listen and drift. The universe
• 1:00:35
  Speaker 1: does not need you to settle its deepest questions before morning.
• 1:00:39
  Speaker 1: And perhaps, when you stop trying to decide whether time
• 1:00:42
  Speaker 1: is flowing or simply being experienced, another possibility becomes easier
• 1:00:47
  Speaker 1: to notice. Maybe the present is not a universal thing
• 1:00:51
  Speaker 1: that the entire cosmos shares. Maybe it is the quiet
• 1:00:55
  Speaker 1: place from which you experience your own path through a
• 1:00:58
  Speaker 1: much larger structure. And as your thoughts become slower, the
• 1:01:02
  Speaker 1: past and future can remain gently beyond your immediate awareness,
• 1:01:07
  Speaker 1: not as things you must reach, but as parts of
• 1:01:09
  Speaker 1: a question that science and philosophy are still quietly exploring.
• 1:01:14
  Speaker 1: For now, there is only this breath, this room. this moment,
• 1:01:19
  Speaker 1: and the soft awareness that somewhere beneath all our ordinary
• 1:01:22
  Speaker 1: ideas about time, something much deeper may still be waiting
• 1:01:26
  Speaker 1: to be understood. You can let the room become very
• 1:01:32
  Speaker 1: quiet now. Perhaps your breathing has already slowed a little.
• 1:01:36
  Speaker 1: Perhaps your eyes are closed. Perhaps you are no longer
• 1:01:39
  Speaker 1: following every sentence, and that is perfectly fine. There is
• 1:01:43
  Speaker 1: nothing to remember, nothing to solve. You are safe. you
• 1:01:47
  Speaker 1: can simply listen and drift and allow these thoughts about
• 1:01:51
  Speaker 1: time to become softer as they pass. For a little while,
• 1:01:56
  Speaker 1: you can return to the smallest thing we began with,
• 1:01:59
  Speaker 1: a clock, a quiet clock somewhere near you. Its hands move,
• 1:02:04
  Speaker 1: one moment follows another, and from inside ordinary life, time
• 1:02:08
  Speaker 1: seems wonderfully simple. There is a past behind you, there
• 1:02:13
  Speaker 1: is a present around you, and there is a future
• 1:02:16
  Speaker 1: somewhere ahead, You have lived through earlier moments, you are
• 1:02:20
  Speaker 1: experiencing this one, and you expect other moments to come.
• 1:02:24
  Speaker 1: That feeling is so familiar that it is almost impossible
• 1:02:28
  Speaker 1: to separate from everyday experience. But physics has asked you
• 1:02:32
  Speaker 1: to look at it from farther away. You discovered that
• 1:02:35
  Speaker 1: clocks can measure different amounts of elapsed time when they
• 1:02:38
  Speaker 1: follow different paths and move differently. You discovered that there
• 1:02:42
  Speaker 1: is no universal cosmic clock that every observer must obey.
• 1:02:47
  Speaker 1: You discovered that two observers can agree perfectly about nearby events,
• 1:02:52
  Speaker 1: while disagreeing about which distant events are happening at the
• 1:02:55
  Speaker 1: same time. You imagined Andromeda more than two million light-years away,
• 1:03:00
  Speaker 1: and realised that even the meaning of its distant now
• 1:03:04
  Speaker 1: can depend on the observer's motion. You looked at the
• 1:03:08
  Speaker 1: stars and discovered that their light carries information from the past.
• 1:03:12
  Speaker 1: You imagined space-time as a vast loaf with different slices
• 1:03:16
  Speaker 1: representing different ways of describing moments. And then you quietly
• 1:03:21
  Speaker 1: approach the block universe idea, a picture in which past,
• 1:03:25
  Speaker 1: present and future can be regarded as different parts of
• 1:03:29
  Speaker 1: one larger structure, not because relativity has proved that the
• 1:03:33
  Speaker 1: future literally exists in some hidden place, not because science
• 1:03:38
  Speaker 1: has discovered a giant cosmic book containing every event, but
• 1:03:42
  Speaker 1: because the structure of spacetime allows a philosophical interpretation in
• 1:03:47
  Speaker 1: which temporal location does not determine whether an event is real.
• 1:03:52
  Speaker 1: That interpretation is called eternalism. Other philosophical views remain possible.
• 1:03:59
  Speaker 1: Presentism says that only the present exists. A growing block
• 1:04:03
  Speaker 1: view gives reality to the past and present, while leaving
• 1:04:06
  Speaker 1: the future open. Eternalism treats past, present and future as
• 1:04:11
  Speaker 1: existing within one larger temporal structure. Physics has not settled
• 1:04:16
  Speaker 1: this philosophical question for everyone, and perhaps you do not
• 1:04:20
  Speaker 1: need it settled. You can simply notice how strange the
• 1:04:24
  Speaker 1: ordinary word now has become. There may be no single
• 1:04:28
  Speaker 1: now shared by every distant observer, and yet your local
• 1:04:32
  Speaker 1: now remains perfectly meaningful. You can still feel the blanket
• 1:04:36
  Speaker 1: around you. You can still hear the quiet sounds of
• 1:04:39
  Speaker 1: the room. You can still notice your breathing. You can
• 1:04:43
  Speaker 1: still remember something that happened earlier today. You can still
• 1:04:46
  Speaker 1: imagine tomorrow. Nothing about relativity requires you to throw away
• 1:04:51
  Speaker 1: these experiences. It simply asks you to separate your experience
• 1:04:56
  Speaker 1: of time from the idea of a universal cosmic present.
• 1:05:00
  Speaker 1: Your experience is local. Your memories are local. Your clocks
• 1:05:05
  Speaker 1: are local. And the universe is much larger than the
• 1:05:08
  Speaker 1: small region in which your ordinary intuition was formed. Perhaps
• 1:05:12
  Speaker 1: the feeling of time flowing is another part of this mystery.
• 1:05:16
  Speaker 1: You experience moments in sequence. A thought appears, then another.
• 1:05:21
  Speaker 1: A sound begins, then it fades. A breath arrives, then leaves.
• 1:05:27
  Speaker 1: Your consciousness seems to move through an ordered stream of experiences.
• 1:05:31
  Speaker 1: But whether the universe itself contains a literal flow of
• 1:05:35
  Speaker 1: time remains a deeper philosophical question. The uploaded source describes
• 1:05:40
  Speaker 1: this idea strongly. suggesting that the feeling of moving from
• 1:05:44
  Speaker 1: past to future may arise from consciousness experiencing events in sequence,
• 1:05:49
  Speaker 1: while the whole history of a life can be represented
• 1:05:52
  Speaker 1: within the block universe picture. That is an interpretation, not
• 1:05:57
  Speaker 1: something established beyond debate. And you can leave it there.
• 1:06:01
  Speaker 1: You do not have to decide whether consciousness travels through time,
• 1:06:05
  Speaker 1: or whether consciousness simply experiences a sequence of events within time.
• 1:06:10
  Speaker 1: You can simply notice the sequence. this breath, then another,
• 1:06:14
  Speaker 1: this sound, then silence, this moment, then another moment, and
• 1:06:20
  Speaker 1: perhaps that simple sequence is all you need to experience tonight.
• 1:06:24
  Speaker 1: The deeper question of determinism can remain open too. If
• 1:06:28
  Speaker 1: every moment has a place within space-time, does that mean
• 1:06:32
  Speaker 1: everything is predetermined? Some interpretations of the block universe can
• 1:06:36
  Speaker 1: be combined with determinism. Other perspectives point toward the uncertainty
• 1:06:41
  Speaker 1: found in quantum physics. The debate remains open, and quantum
• 1:06:46
  Speaker 1: uncertainty by itself does not automatically explain free will. So
• 1:06:51
  Speaker 1: there is no need to turn the question into a conclusion.
• 1:06:55
  Speaker 1: You can allow uncertainty to remain uncertainty. Sometimes the quietest
• 1:07:00
  Speaker 1: scientific answer is simply that we do not yet know,
• 1:07:04
  Speaker 1: and that can be peaceful. You do not need the
• 1:07:06
  Speaker 1: universe to reveal everything before you rest. You can look
• 1:07:10
  Speaker 1: at the night sky and remember only one simple thing.
• 1:07:14
  Speaker 1: The light from distant stars has travelled. Some of it
• 1:07:18
  Speaker 1: has travelled for years, some for centuries, some for millions
• 1:07:22
  Speaker 1: or billions of years. The sky you see is therefore
• 1:07:26
  Speaker 1: filled with different pieces of cosmic history arriving together. The
• 1:07:31
  Speaker 1: present in your room can receive light from the distant past.
• 1:07:35
  Speaker 1: Your eyes can rest beneath a sky containing many different
• 1:07:38
  Speaker 1: ages at once. And perhaps this gives you one final
• 1:07:42
  Speaker 1: way to think about the strange relationship between past, present
• 1:07:46
  Speaker 1: and future. Maybe the universe is not a single enormous
• 1:07:50
  Speaker 1: clock ticking toward one shared future. Maybe it is better
• 1:07:55
  Speaker 1: imagined as a vast arrangement of events connected through space
• 1:07:59
  Speaker 1: and time, with different observers describing that arrangement from different
• 1:08:03
  Speaker 1: positions and motions. Your own life is one path within
• 1:08:08
  Speaker 1: that structure. The moments you remember belong to your history.
• 1:08:12
  Speaker 1: The moment you are experiencing belongs to your present experience.
• 1:08:17
  Speaker 1: The moments you have not experienced remain beyond your awareness.
• 1:08:21
  Speaker 1: And whether those future moments already have a place in
• 1:08:24
  Speaker 1: the deeper structure of reality is a question that science
• 1:08:28
  Speaker 1: and philosophy continue to explore. you can leave the question
• 1:08:32
  Speaker 1: gently unanswered. Because right now, you do not need to
• 1:08:36
  Speaker 1: know what the universe is doing everywhere. You only need
• 1:08:39
  Speaker 1: to notice that you are here. You are resting. You
• 1:08:43
  Speaker 1: are breathing. The earth is turning beneath you. The planet
• 1:08:47
  Speaker 1: is travelling around the sun. The solar system is moving
• 1:08:50
  Speaker 1: through the Milky Way. The Milky Way is part of
• 1:08:54
  Speaker 1: a much larger universe. And through all of this motion,
• 1:08:58
  Speaker 1: your room can feel completely still. There is something beautiful
• 1:09:02
  Speaker 1: in that. Motion can surround stillness. Time can surround a moment.
• 1:09:08
  Speaker 1: The distant past can reach you through light. And the
• 1:09:11
  Speaker 1: future can remain a quiet mystery without demanding your attention.
• 1:09:16
  Speaker 1: Perhaps the present is not a universal boundary stretching across
• 1:09:20
  Speaker 1: the entire cosmos. Perhaps it is simply the moment you
• 1:09:24
  Speaker 1: are experiencing from where you are. And perhaps that is enough.
• 1:09:29
  Speaker 1: You do not need to hold the whole universe in
• 1:09:31
  Speaker 1: your mind. You can let the thoughts become lighter now.
• 1:09:36
  Speaker 1: The clock can continue without you watching it. The stars
• 1:09:39
  Speaker 1: can continue shining without you counting them. The distant galaxies
• 1:09:43
  Speaker 1: can continue carrying their ancient light across space. The universe
• 1:09:48
  Speaker 1: does not need your attention to keep existing. You can rest.
• 1:09:52
  Speaker 1: You can breathe. You can allow the room to become softer.
• 1:09:56
  Speaker 1: And if the block universe picture is one useful way
• 1:09:59
  Speaker 1: of understanding reality, then every moment has its own quiet place,
• 1:10:05
  Speaker 1: not rushing toward you, not being chased by you, simply
• 1:10:09
  Speaker 1: belonging to the enormous structure of existence. Your past does
• 1:10:14
  Speaker 1: not need to return. Your future does not need to
• 1:10:17
  Speaker 1: hurry toward you. And your present does not need to
• 1:10:20
  Speaker 1: become universal in order to be meaningful. This moment is enough.
• 1:10:25
  Speaker 1: This breath is enough. This quiet is enough. And perhaps,
• 1:10:29
  Speaker 1: somewhere beyond the edges of everything you can imagine, time
• 1:10:33
  Speaker 1: has an even gentler secret waiting to be understood. But
• 1:10:37
  Speaker 1: you do not have to understand it tonight. You can
• 1:10:40
  Speaker 1: simply let the question drift away. and so our journey
• 1:10:44
  Speaker 1: drifts quietly to its end. Whether you are still listening
• 1:10:48
  Speaker 1: beneath the glow of your screen, or already floating somewhere
• 1:10:51
  Speaker 1: between dreams and distant stars, thank you for travelling here tonight,
• 1:10:56
  Speaker 1: through clocks, distant galaxies, ancient light, space-time, and the quiet
• 1:11:02
  Speaker 1: mystery of what it means to be here now. If
• 1:11:06
  Speaker 1: this wandering brought you a little calm, you are welcome
• 1:11:09
  Speaker 1: to subscribe, or share it with someone who could use
• 1:11:12
  Speaker 1: a gentler night beneath the cosmos. For now, rest well.
• 1:11:17
  Speaker 1: The stars will keep shining, the planets will keep turning,
• 1:11:22
  Speaker 1: the clocks will keep counting, and the universe will carry
• 1:11:26
  Speaker 1: on softly around you while you sleep. And so, our
• 1:11:32
  Speaker 1: journey quietly comes to an end. You don't need to
• 1:11:35
  Speaker 1: understand everything about time tonight. Let the clocks keep ticking,
• 1:11:40
  Speaker 1: Let the stars keep shining and let the earth keep
• 1:11:43
  Speaker 1: turning beneath you. The past can rest behind you. The
• 1:11:48
  Speaker 1: future can remain far away and this quiet moment is enough.
• 1:11:52
  Speaker 1: You are safe. There is nothing to do now. Just
• 1:11:55
  Speaker 1: breathe slowly, close your eyes and drift. The universe will
• 1:12:00
  Speaker 1: keep moving softly around you while you sleep. Good night.