Latest / Daniel and Kelly’s Extraordinary Universe / Daniel answers Listener Questions about hawking radiation, 5G networks and wireless phone chargers!

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Daniel answers Listener Questions about hawking radiation, 5G networks and wireless phone chargers! · Daniel and Kelly’s Extraordinary Universe

• 0:08
  Speaker 1: The world around you is like an amazing mirage. That
• 0:12
  Speaker 1: rock you see over there, it's not actually one object,
• 0:16
  Speaker 1: but a collection of ten to the twenty five particles,
• 0:20
  Speaker 1: all shaking and buzzing and wiggling together. That star you
• 0:24
  Speaker 1: see in the sky, those are photons generated from zillions
• 0:28
  Speaker 1: of kilograms of hot plasma that traveled billions of light
• 0:32
  Speaker 1: years before hitting your retina. That chair that's holding you up,
• 0:37
  Speaker 1: that's not solid. It's actually a web of atoms linked
• 0:40
  Speaker 1: together by electromagnetic forces. Physics gives you a way to
• 0:44
  Speaker 1: peel back a layer of reality and figure out what's
• 0:47
  Speaker 1: happening underneath, to see the world in a new way
• 0:50
  Speaker 1: by understanding its nature at the microscopic level and seeing
• 0:55
  Speaker 1: how all the incredible complexity in the insanity in our
• 0:58
  Speaker 1: universe arises from the simple interactions of a small number
• 1:02
  Speaker 1: of pieces. It's bonkers, but it's beautiful. Hi. I'm Daniel,
• 1:22
  Speaker 1: I'm a particle physicist, and I'm in love with the
• 1:25
  Speaker 1: insanity of our universe. And welcome to our podcast Daniel
• 1:30
  Speaker 1: and Jorge Explain the Universe, a production of My Heart
• 1:34
  Speaker 1: Radio in which we take a mental journey through the cosmos.
• 1:38
  Speaker 1: We think about how everything out there works. We try
• 1:41
  Speaker 1: to understand the craziness of neutron stars, of black holes evaporating,
• 1:46
  Speaker 1: the tiny, little, buzzing particles that make it all up.
• 1:50
  Speaker 1: We try to take the whole universe and wrap it
• 1:53
  Speaker 1: up so that you can understand it, or at least
• 1:56
  Speaker 1: understand a little piece of it. Because the universe is
• 2:00
  Speaker 1: not something that is understood. It remains an enormous cosmic mystery.
• 2:05
  Speaker 1: Though we have peeled back layers of reality to see
• 2:08
  Speaker 1: that most of what we are looking at is made
• 2:11
  Speaker 1: of elements, and those elements are made of even smaller particles,
• 2:14
  Speaker 1: which are made of even smaller particles. We have dug
• 2:17
  Speaker 1: deep into the nature of reality, but our questions are
• 2:21
  Speaker 1: not yet answered. We need to understand, and we have
• 2:24
  Speaker 1: not yet understood, the remain enormous mysteries about the nature
• 2:28
  Speaker 1: of the universe. What is most of the matter out
• 2:31
  Speaker 1: there in the universe? What is driving the acceleration of
• 2:34
  Speaker 1: the cosmic expansion of the universe. We have really basic
• 2:38
  Speaker 1: questions about how things work. But those questions are not failings.
• 2:43
  Speaker 1: They're not a disappointment in science. They are exciting opportunities.
• 2:47
  Speaker 1: They are the threads that we will pull on to
• 2:49
  Speaker 1: help us reveal the nature of the universe. They are
• 2:53
  Speaker 1: the clues that will lead us to incredible, mind blowing
• 2:56
  Speaker 1: discoveries about the nature of the cosmos, just the way
• 3:00
  Speaker 1: that our journey through physics so far has revealed so
• 3:03
  Speaker 1: many times that the universe is not the way that
• 3:06
  Speaker 1: we thought it was, since our intuition built up from
• 3:09
  Speaker 1: the times that we climbed down from the trees and
• 3:12
  Speaker 1: walked around on two feet and tried to understand this
• 3:14
  Speaker 1: world around us, that that intuition has often led us astray,
• 3:18
  Speaker 1: and that when we follow the science, when we carefully
• 3:21
  Speaker 1: build up knowledge by asking and answering questions, is when
• 3:25
  Speaker 1: we reveal the true nature of the universe. And it's
• 3:28
  Speaker 1: crazy and it's weird, and it violates our intuitions, but
• 3:32
  Speaker 1: it's still beautiful and it's our universe. And that's why
• 3:36
  Speaker 1: on our podcast we love to celebrate questions, not just
• 3:39
  Speaker 1: questions asked by scientists working at the forefront of knowledge
• 3:43
  Speaker 1: peering out into the depths of the universe, but your questions,
• 3:46
  Speaker 1: our questions, everybody's questions, Because if you wonder about the
• 3:51
  Speaker 1: nature of the universe, if you yearn to understand the
• 3:53
  Speaker 1: truth about reality. Then you are a scientist, then you
• 3:57
  Speaker 1: are asking questions. Then you would be surprised to discover
• 4:01
  Speaker 1: how many of your questions are the same questions being
• 4:04
  Speaker 1: asked by scientists. So don't be embarrassed to ask your questions,
• 4:09
  Speaker 1: ask them out loud, talk to people about them, try
• 4:11
  Speaker 1: to find the answers, and if you can't, send them
• 4:14
  Speaker 1: to us, because we love answering your questions. Everybody out
• 4:18
  Speaker 1: there who has thought about a topic and not quite
• 4:20
  Speaker 1: understood it, or heard an explanation about something weird and
• 4:24
  Speaker 1: crazy and it didn't really sink in, please write to us.
• 4:28
  Speaker 1: We will answer your questions. We're available online. We answer
• 4:31
  Speaker 1: emails to questions at Daniel and Jorge dot com. We
• 4:35
  Speaker 1: respond on Twitter at Daniel and Jorge, and sometimes we'll
• 4:40
  Speaker 1: take some of these questions and feature them on the
• 4:43
  Speaker 1: podcast and so on. Today's program will be answering listener
• 4:52
  Speaker 1: questions about Hawking, radiation, five G networks, and wireless charging.
• 4:58
  Speaker 1: As you might have gathered, my co host friend and
• 5:01
  Speaker 1: collaborator Jorge him is not around today, so I'm taking
• 5:05
  Speaker 1: this opportunity to dig into our backlog of wonderful, wonderful
• 5:10
  Speaker 1: questions asked to us by listeners. So I'll be digging
• 5:13
  Speaker 1: into a few questions from listeners, and you have lots
• 5:16
  Speaker 1: of opportunities to get your questions answers. You can email us,
• 5:19
  Speaker 1: you can tweet us. You can also come to my
• 5:22
  Speaker 1: public office hours. I hang out on zoom and answer
• 5:25
  Speaker 1: questions from anybody out there who's interested in physics and
• 5:28
  Speaker 1: wants to understand the universe. Check out my website sites
• 5:32
  Speaker 1: dot U, c I, dot E, d U slash Daniel
• 5:35
  Speaker 1: for all the details about the next upcoming public office hours.
• 5:40
  Speaker 1: All right, so let's dig into it and start answering
• 5:42
  Speaker 1: listener questions. This first one is an awesome question about
• 5:46
  Speaker 1: hawking radiation, black holes, and dark matter. Hello Dan, My
• 5:52
  Speaker 1: question is about talking radiation and the operation of BLAT. So,
• 5:57
  Speaker 1: if there is there's matter inside my cote, what had
• 6:00
  Speaker 1: it been necessary for hawking radiation to interact with the
• 6:03
  Speaker 1: dark matter in order to produce like holes completely. This
• 6:07
  Speaker 1: is such a fun question because it gives me a
• 6:09
  Speaker 1: little glimpse into what's going on in somebody's mind. Somebody's
• 6:12
  Speaker 1: thinking about black holes and hawking radiation and wondering how
• 6:16
  Speaker 1: that happens, and all of a sudden they run into
• 6:18
  Speaker 1: a wall. They think a whole lot of a second,
• 6:20
  Speaker 1: this doesn't make sense. How can the products of hawking
• 6:23
  Speaker 1: radiation annihilate with the dark matter inside the black holes?
• 6:27
  Speaker 1: And so they come to that point they don't understand it,
• 6:29
  Speaker 1: and that's when they reach out. And I love seeing
• 6:32
  Speaker 1: people do that, taking two ideas and trying to fit
• 6:34
  Speaker 1: them together into one understanding, because that's what we do
• 6:38
  Speaker 1: in physics, right We want a single understanding that explains everything.
• 6:43
  Speaker 1: You can't have one explanation for this thing and a
• 6:45
  Speaker 1: totally different explanation for that. We want a complete, holistic
• 6:49
  Speaker 1: view of the universe. So kudos to you for asking
• 6:52
  Speaker 1: this question. But before I dive into the details of
• 6:55
  Speaker 1: dark matter and black holes and hawking radiation, let's back
• 6:59
  Speaker 1: up and make sure we understand the basics of what's
• 7:01
  Speaker 1: going on in hawking radiation, because I think there might
• 7:04
  Speaker 1: be a small misunderstanding in the process, which is actually
• 7:07
  Speaker 1: leading to the core of this question. The first thing
• 7:10
  Speaker 1: you should understand about hawking radiation is that we do
• 7:13
  Speaker 1: not have a good microscopic understanding of how it works.
• 7:18
  Speaker 1: You know, we like to look at the world and
• 7:20
  Speaker 1: peel it back and understand how it works. At the
• 7:22
  Speaker 1: particle level and sometimes work back up from the particle
• 7:26
  Speaker 1: level to the macroscopic and say, okay, we understand this
• 7:29
  Speaker 1: temperature is just the buzzing of particles whizzing around, or
• 7:32
  Speaker 1: an electrical conductivity comes from how electrons are filling their orbitals, etcetera, etcetera.
• 7:38
  Speaker 1: But that's not something we have yet for Hawking radiation
• 7:41
  Speaker 1: because it relies on two things that don't play well together,
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  Speaker 1: tiny little quantum particles which obey the rules of quantum
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  Speaker 1: mechanics and gravity, and gravity and quantum mechanics don't play
• 7:54
  Speaker 1: very nicely together. We do not understand gravitational effects on
• 7:58
  Speaker 1: individual quantum part nicles. That would require a theory of
• 8:02
  Speaker 1: quantum gravity, which we don't have. So Hawking radiation actually
• 8:07
  Speaker 1: doesn't come from a microscopic understanding of what happens to
• 8:10
  Speaker 1: quantum particles near the edge of the black holes. No,
• 8:13
  Speaker 1: it comes from statistical and thermal physics. It's come from
• 8:17
  Speaker 1: thinking about black holes as big objects made of many particles,
• 8:21
  Speaker 1: and thinking about them statistically, sort of the same way
• 8:24
  Speaker 1: we think about like temperature and pressure. For a gas
• 8:27
  Speaker 1: pressure doesn't make any sense, It doesn't have a meaning
• 8:30
  Speaker 1: for an individual particle. It's a property only of a gas.
• 8:33
  Speaker 1: So this is the way that Hawking derived this concept
• 8:36
  Speaker 1: of a temperature and entropy for a black hole. He
• 8:40
  Speaker 1: invented this field of black hole thermodynamics, and from it
• 8:45
  Speaker 1: came this concept of Hawking radiation. But we don't have
• 8:48
  Speaker 1: a microscopic understanding of what's actually happening at the particle level.
• 8:53
  Speaker 1: But we do have some not terrible kind of hand
• 8:57
  Speaker 1: wavy descriptions for how Hawking radiation might work. Now, they
• 9:01
  Speaker 1: don't actually work theoretically on the quantum level if you
• 9:04
  Speaker 1: try to do these calculations, but they're a good way
• 9:06
  Speaker 1: to sort of guide your thinking for what might be
• 9:09
  Speaker 1: happening and help you to think about it. Okay, so
• 9:12
  Speaker 1: what is our understanding of Hawking radiation at the microscopic level.
• 9:17
  Speaker 1: So the space near a black hole, of course has
• 9:20
  Speaker 1: energy in it. All of space has energy in it
• 9:22
  Speaker 1: because space is filled with quantum fields and those fields
• 9:25
  Speaker 1: can't relax all the way down to zero, and sometimes
• 9:29
  Speaker 1: that energy in the field turns into a particle or
• 9:32
  Speaker 1: a particle and an antiparticle. So this happens all the time.
• 9:36
  Speaker 1: Things turn into an electron and apositron, and then they
• 9:38
  Speaker 1: annihilate back and they go back into the field. So
• 9:41
  Speaker 1: this is going on all the times, this frothing at
• 9:44
  Speaker 1: the quantum level, even around black holes. Now, when this
• 9:47
  Speaker 1: happens in the vicinity of a black hole, sometimes these
• 9:51
  Speaker 1: particles get a little extra boost of energy because there
• 9:54
  Speaker 1: is more energy around the black hole. There's the gravitational
• 9:58
  Speaker 1: energy of the black hole. And this is the wonky
• 10:01
  Speaker 1: part because we don't really understand how gravity interacts with particles.
• 10:05
  Speaker 1: We can't do experiments to see the gravitational effect on
• 10:09
  Speaker 1: particles because particles have almost no mass and gravity is
• 10:13
  Speaker 1: super nuber weak, so we haven't been able to do
• 10:16
  Speaker 1: these experiments. But anyway, imagine that somehow this particle antiparticle
• 10:20
  Speaker 1: pair gets extra energy because of the gravitational field of
• 10:24
  Speaker 1: the black hole. Now, one of these particles happens to
• 10:28
  Speaker 1: leave the area of the black hole. They were created
• 10:31
  Speaker 1: outside the event horizon, so that's cool. The other one
• 10:34
  Speaker 1: falls back into the black hole. Let's think first about
• 10:37
  Speaker 1: the one that leaves. What happens to it, Well, it
• 10:40
  Speaker 1: flies off into the universe. Maybe it's an electron, Maybe
• 10:43
  Speaker 1: it's a positron. Maybe it's a top cork, maybe it's
• 10:46
  Speaker 1: a gluon. It can be any kind of particle because
• 10:49
  Speaker 1: the quantum field can fluctuate into any kind of particle.
• 10:52
  Speaker 1: There are some different probabilities based on the masses, but
• 10:55
  Speaker 1: that doesn't really matter. But that particle leaves and it
• 10:58
  Speaker 1: takes with it some energy. Where did that energy come from?
• 11:01
  Speaker 1: Part of it came just from the quantum field, but
• 11:03
  Speaker 1: part of it also came from the gravitational energy of
• 11:07
  Speaker 1: the black hole. And if you take the gravitational energy,
• 11:11
  Speaker 1: you are decreasing the mass of the black hole. Now
• 11:14
  Speaker 1: you might be thinking, hold on a second, how does
• 11:16
  Speaker 1: the mass leave the black hole? This particle was never
• 11:20
  Speaker 1: in the black hole, right, that's true, But remember the
• 11:24
  Speaker 1: mass of the black hole is not like the amount
• 11:26
  Speaker 1: of stuff in the black hole. It's like a meter
• 11:29
  Speaker 1: that tells you how much energy is stored in the
• 11:32
  Speaker 1: black hole. Doesn't matter what the form of that energy is.
• 11:35
  Speaker 1: It can be photons, it can be protons, it can
• 11:38
  Speaker 1: be something else super duper weird. It can be a
• 11:41
  Speaker 1: singularity that has no like state of matter we can
• 11:44
  Speaker 1: think about or calculate. The mass of the black hole
• 11:46
  Speaker 1: comes from the energy stored within it. So if you
• 11:49
  Speaker 1: remove energy from the black hole, you reduce its mass.
• 11:53
  Speaker 1: You can reduce the mass of a black hole without
• 11:56
  Speaker 1: carrying a particle from inside the event horizon to outside
• 12:00
  Speaker 1: the event horizon. And you might be thinking, hold on
• 12:02
  Speaker 1: a second, that's crazy. I thought black holes can never
• 12:05
  Speaker 1: release information, they could never lose anything. And it's true
• 12:09
  Speaker 1: that nothing can leave if it's inside the event horizon.
• 12:12
  Speaker 1: No information can escape. However, the black hole's energy goes
• 12:17
  Speaker 1: beyond the edge of the event horizon. It's gravitational influence
• 12:21
  Speaker 1: does not stop at the event horizon. The event horizon
• 12:24
  Speaker 1: is just a place after which all of your paths
• 12:27
  Speaker 1: now point towards the center of the black hole. It's
• 12:30
  Speaker 1: not the edge of the black hole's influence on the universe,
• 12:34
  Speaker 1: and that influence can extend to things created outside the
• 12:37
  Speaker 1: event horizon, and it can lose that energy once it's
• 12:41
  Speaker 1: donated it to those particles, and when it loses that energy,
• 12:45
  Speaker 1: it loses some mass. All right. So now we have
• 12:49
  Speaker 1: a sort of hand wavy understanding of how hawking radiation
• 12:53
  Speaker 1: might work at the microscopic level. Let's get to the question.
• 12:57
  Speaker 1: The question was about the particle that goes into the
• 12:59
  Speaker 1: black hole, not the one that escapes, and it was asking,
• 13:01
  Speaker 1: if the particle goes into the black hole, doesn't it
• 13:04
  Speaker 1: need to find something to annihilate with the sort of
• 13:07
  Speaker 1: contribute back its energy to the black hole. And if
• 13:11
  Speaker 1: black holes are mostly dark matter, then how can they
• 13:14
  Speaker 1: do that because it can't interact with dark matter. All right,
• 13:17
  Speaker 1: So a lot of things to talk about there. First
• 13:19
  Speaker 1: of all, we don't know how much dark matter is
• 13:22
  Speaker 1: in black holes. I've said on the podcast, it's almost
• 13:24
  Speaker 1: certain that there is some, and that's true. But remember
• 13:27
  Speaker 1: that dark matter has a harder time falling into black
• 13:30
  Speaker 1: holes because it can't get rid of its angular momentum
• 13:34
  Speaker 1: like other kinds of matter. It can spin around a
• 13:36
  Speaker 1: black hole, but other kinds of matter can lose their
• 13:39
  Speaker 1: angular momentum by radiating off energy, for example, or bumping
• 13:43
  Speaker 1: into each other. These kinds of interactions are crucial for
• 13:46
  Speaker 1: losing your angular momentum and falling into the black hole,
• 13:49
  Speaker 1: falling out of orbit and falling into the black hole.
• 13:52
  Speaker 1: Dark matter can't do that, so it stays fluffy. And
• 13:55
  Speaker 1: so we think that there is dark matter in black holes,
• 13:58
  Speaker 1: we don't really know how much. It may not be
• 14:00
  Speaker 1: that it's dominated by dark matter, but even still, let's
• 14:03
  Speaker 1: imagine that the black hole is filled with dark matter.
• 14:07
  Speaker 1: What happens to this particle that falls into the black hole, Well,
• 14:10
  Speaker 1: it doesn't actually need to annihilate with anything to contribute
• 14:14
  Speaker 1: to the mass of the black hole. Remember, the mass
• 14:17
  Speaker 1: of the black holes just a measure of how much
• 14:19
  Speaker 1: energy is stored inside it. It's not necessary for that
• 14:22
  Speaker 1: particle to annihilate with something else and return its energy.
• 14:26
  Speaker 1: It already has returned its energy. Everything that's in the
• 14:29
  Speaker 1: vicinity of the black hole contributes to the gravitational system
• 14:32
  Speaker 1: and therefore to the mass of the black hole. If
• 14:36
  Speaker 1: particles inside the black hole change from photons to particle
• 14:39
  Speaker 1: antiparticle pairs, it has no effect on the black hole's mass.
• 14:43
  Speaker 1: So if there is dark matter inside black holes, it
• 14:46
  Speaker 1: doesn't affect this Hawking radiation alright. So the things to
• 14:50
  Speaker 1: remember about hawking radiation are number one, that we only
• 14:54
  Speaker 1: have a hand wavy description of the microscopic effects. We
• 14:57
  Speaker 1: don't really understand how it works. Our understanding of hawking
• 15:01
  Speaker 1: radiation is at the level of statistical physics, talking about many,
• 15:05
  Speaker 1: many particles and averaging over lots of quantum details that
• 15:08
  Speaker 1: we do not yet understand. And that hawking radiation happens
• 15:13
  Speaker 1: outside the black hole, borrowing some of the gravitational energy
• 15:17
  Speaker 1: from the black hole and carrying it off with it,
• 15:20
  Speaker 1: because you can interact with the black hole without actually
• 15:23
  Speaker 1: falling into it, and that means that it's possible to
• 15:25
  Speaker 1: steal a little bit of its energy and therefore decrease
• 15:29
  Speaker 1: its mass. And that's sort of our understanding of Hawking
• 15:33
  Speaker 1: radiation and how black holes can't evaporate. All right. Thank
• 15:37
  Speaker 1: you for that oh wonderful question, and thank you for
• 15:39
  Speaker 1: thinking deeply about how black holes work and how they evaporate,
• 15:42
  Speaker 1: and what might be inside them and what's going on
• 15:44
  Speaker 1: inside the black holes. They are one of my favorite
• 15:47
  Speaker 1: mysteries because they potentially contain the answers just so many
• 15:51
  Speaker 1: basic questions about how the universe works, what happens to
• 15:55
  Speaker 1: quantum particles when gravity gets really really strong, and the
• 15:58
  Speaker 1: gravitational effects and quantum effects both become important. We have
• 16:02
  Speaker 1: almost nowhere in the universe we can probe quantum gravity
• 16:06
  Speaker 1: because it's so hard to study. But the center of
• 16:09
  Speaker 1: black holes is that place. Unfortunately, of course, we can't
• 16:13
  Speaker 1: see what's inside them, all right, So thanks to that question,
• 16:16
  Speaker 1: I have more questions. I want to get to but
• 16:18
  Speaker 1: first let's take a quick break. All right, we're back
• 16:34
  Speaker 1: in today. It's just me, Daniel. I'm a particle of
• 16:36
  Speaker 1: physicists by day and by night I like to answer
• 16:39
  Speaker 1: physics questions from the public, and today we are answering
• 16:42
  Speaker 1: questions sent in by listeners. We thought about something or
• 16:46
  Speaker 1: read something and wanted to hear it explained. And today's
• 16:49
  Speaker 1: episode is focused on the topic of radiation. We talked
• 16:53
  Speaker 1: about radiation from black holes, and here's a question from
• 16:56
  Speaker 1: listeners about another kind of potential radiation. Low Daniel Horrey,
• 17:00
  Speaker 1: this is a Mario from Los Angeles. While I was
• 17:02
  Speaker 1: listening to your show, I heard a commercial about five
• 17:04
  Speaker 1: G and I got curious because there's a lot of
• 17:07
  Speaker 1: conspiracy theories about the pandemic and five G. I was
• 17:10
  Speaker 1: hoping you guys could explain the effects of five G
• 17:13
  Speaker 1: have on our society given informed an opinion about the
• 17:16
  Speaker 1: conspiracy theories. Thank you. Okay, So this is a really
• 17:20
  Speaker 1: interesting question and one that actually a few people have
• 17:23
  Speaker 1: written to us about. So I thought it'd be interesting
• 17:25
  Speaker 1: to sort of take the physics point of view. What
• 17:28
  Speaker 1: do we know about five G networks? What are they,
• 17:30
  Speaker 1: how do they work, what's the physics of five G
• 17:33
  Speaker 1: and how it interacts with a human body, and then
• 17:36
  Speaker 1: you'll have everything you need to make up your own
• 17:38
  Speaker 1: mind about whether or not five G is a good idea. Alright,
• 17:42
  Speaker 1: so first of all, what is five G. Five G
• 17:45
  Speaker 1: means fifth generation cell phone networks. People have been upgrading
• 17:50
  Speaker 1: and improving our cell phone network to make them faster
• 17:53
  Speaker 1: and more reliable, etcetera. And now they have the fifth
• 17:56
  Speaker 1: generation which is now being installed. Five G is a thing.
• 17:59
  Speaker 1: It exists, it's out there in patches in our world.
• 18:03
  Speaker 1: It's not complete, it's not everywhere. They're still putting it together,
• 18:07
  Speaker 1: so it's sort of in its embryonic phase. And it's
• 18:09
  Speaker 1: an exciting technology because potentially it could deliver data to
• 18:13
  Speaker 1: your devices a hundred or more times faster than the
• 18:17
  Speaker 1: four gene networks, and so that would allow a lot
• 18:19
  Speaker 1: of things to happen. You can have a screen on
• 18:21
  Speaker 1: the door to your refrigerator to let's use stream movies
• 18:24
  Speaker 1: while you're deciding what to eat. You can have everything connecting.
• 18:27
  Speaker 1: You can just send a lot more data everywhere. So
• 18:30
  Speaker 1: if you're excited about data, then you should be excited
• 18:32
  Speaker 1: about five gene networks. So what's different between five G
• 18:37
  Speaker 1: and four G? Right, the fourth generation of network and
• 18:40
  Speaker 1: what makes people so interested and excited and concerned about it.
• 18:44
  Speaker 1: While there are a couple of differences about five G,
• 18:46
  Speaker 1: there's some sort of smaller ones, like the way they
• 18:49
  Speaker 1: organize the data to make it faster, in the way
• 18:51
  Speaker 1: they route it from tower to tower, But the major
• 18:53
  Speaker 1: differences are one that the antennas are directional. So an
• 18:57
  Speaker 1: antenna is just a bunch of electrons with going in
• 19:00
  Speaker 1: a conducting rod that generates electromagnetic fields, and often these
• 19:04
  Speaker 1: antennas broadcast in every direction simultaneously, so then the power
• 19:09
  Speaker 1: of the radiation, the intensity of the signal decreases as
• 19:13
  Speaker 1: you get further away from the antenna, but sort of
• 19:15
  Speaker 1: the same way every direction. These five G antennas are directional.
• 19:19
  Speaker 1: They can be focused in certain directions to provide like
• 19:22
  Speaker 1: longer range connections in certain directions and to black out
• 19:26
  Speaker 1: other directions. And this way you can sort of like
• 19:28
  Speaker 1: more intelligently decide where you want your coverage. So that's
• 19:32
  Speaker 1: number one, they have these directional antennas. Number two, and
• 19:35
  Speaker 1: this is probably the big one, is that they're using
• 19:38
  Speaker 1: a different frequency to communicate the wavelength of these signals
• 19:43
  Speaker 1: is something like ten millimeters. The frequency is like in
• 19:46
  Speaker 1: the range of twenty to fifty giga hurts. And this
• 19:49
  Speaker 1: is interesting, and this is new because it's ten times
• 19:53
  Speaker 1: higher frequency shorter wavelength than have existed in cell phones before.
• 19:59
  Speaker 1: It's not the first time we've seen technology that emits
• 20:02
  Speaker 1: radiation in this wavelength or frequency spectrum. It's the same
• 20:05
  Speaker 1: sort of wavelength this is used in those airport scanners
• 20:08
  Speaker 1: when you go to the airport and they try to
• 20:10
  Speaker 1: figure out if you have something in your pocket. But
• 20:12
  Speaker 1: these are much lower power than those airport scanners. On
• 20:15
  Speaker 1: the other hand, they're kind of on all the time,
• 20:17
  Speaker 1: so they're sort of blanketing the world with this radiation.
• 20:20
  Speaker 1: And the question is about the long term exposure to
• 20:24
  Speaker 1: this wavelength of radiation, and that's where I think the
• 20:27
  Speaker 1: concern arises. And you may have heard some conspiracy theories
• 20:30
  Speaker 1: about how this has created the pandemic or responded to
• 20:33
  Speaker 1: the pandemic, and that, of course, is all just bonkers.
• 20:36
  Speaker 1: There's no connection between five G and the pandemic. There
• 20:40
  Speaker 1: are no microchips inside the vaccines. All that stuff is
• 20:44
  Speaker 1: just fearmongering nonsense. There are some interesting physics questions about
• 20:48
  Speaker 1: five G, and some interesting medical questions about the impact
• 20:53
  Speaker 1: of five G on the human body, and some interesting
• 20:56
  Speaker 1: policy questions about how to roll out of technology. How
• 20:59
  Speaker 1: many st you really need to have done before you
• 21:02
  Speaker 1: take a risk and roll out something new. That's all fascinating,
• 21:05
  Speaker 1: but let's push aside for now the crazy conspiracy theories
• 21:09
  Speaker 1: connect to the pandemic. We're in seeing lizard people using
• 21:11
  Speaker 1: five G to control your minds, And let's just talk
• 21:14
  Speaker 1: about the physics. So I said radiation, and I talked
• 21:17
  Speaker 1: about the intensity of it. Does that mean that these
• 21:19
  Speaker 1: things are like radioactive, that you're basically living next to
• 21:22
  Speaker 1: a nuclear power plant? No, no, no, Remember that radiation
• 21:26
  Speaker 1: is a very very broad term. It includes any sort
• 21:29
  Speaker 1: of wave or particle which transmits energy, including yes, radioactivity
• 21:35
  Speaker 1: from nuclear power plants. But that's not what we're talking
• 21:38
  Speaker 1: about today. We're talking about the kind of radiation that's
• 21:40
  Speaker 1: just photons, right, just a kind of light electro magnetic radiation,
• 21:45
  Speaker 1: which is a very very broad term. But all of
• 21:48
  Speaker 1: it is just a different kind of photon, and those
• 21:51
  Speaker 1: photons are different based on their frequency, based on the
• 21:54
  Speaker 1: wavelength of the photon, and different wavelength photons we give
• 21:59
  Speaker 1: different names, from very long wavelength photons, which are like
• 22:03
  Speaker 1: radio waves or infrared waves, up to visible light, of course,
• 22:07
  Speaker 1: which is just photons of a certain frequency that hits
• 22:10
  Speaker 1: your eyes and your brain knows how to interpret. Up
• 22:13
  Speaker 1: to ultra violet light, which has a frequency higher than
• 22:17
  Speaker 1: you can see, all the way up to X rays
• 22:19
  Speaker 1: and gamma rays. It's all part of one continuous spectrum.
• 22:23
  Speaker 1: The difference between a gamma ray and a photon that
• 22:26
  Speaker 1: makes up a radio wave is just the wavelength of
• 22:29
  Speaker 1: that photon, and all these photons can be used to
• 22:32
  Speaker 1: encode information. So we use electromagnetic radiation as a way
• 22:37
  Speaker 1: to pass information around, and you can think of it
• 22:40
  Speaker 1: as waves, right. We think about radio waves as waves
• 22:42
  Speaker 1: washing over the earth surface. TV antennas and all that
• 22:45
  Speaker 1: kind of stuff send electromagnetic waves, and you can think
• 22:49
  Speaker 1: about it as waves. That makes perfect sense. But it's
• 22:51
  Speaker 1: also important to remember that it's actually made of photons.
• 22:55
  Speaker 1: It's made of individual particles, and that's important because the
• 23:00
  Speaker 1: energy of the individual photons depends on the wavelength of
• 23:04
  Speaker 1: the radiation. So when we say higher frequency, we mean
• 23:08
  Speaker 1: there's more energy per photon, so you v photons have
• 23:13
  Speaker 1: more energy in them than radio wave photons. Gamma ray
• 23:17
  Speaker 1: photons have even more energy in them. X ray photons
• 23:20
  Speaker 1: have a lot of energy in them, more than visible
• 23:23
  Speaker 1: light photons. And it's broken up into these pieces, right.
• 23:27
  Speaker 1: You can't have half a photon or one and a
• 23:29
  Speaker 1: half photons. If you have a beam of light in
• 23:32
  Speaker 1: the X ray part of the spectrum, then each of
• 23:34
  Speaker 1: those photons has a lot of energy. If you have
• 23:37
  Speaker 1: a beam of light in the infrared, than each of
• 23:39
  Speaker 1: those photons has less energy. And that turns out to
• 23:43
  Speaker 1: be really important because when the photon hits your body,
• 23:46
  Speaker 1: it's the energy of that individual photon that determines whether
• 23:50
  Speaker 1: or not it can ionize something, whether or not it
• 23:53
  Speaker 1: can kick an electron, for example, out of an atom,
• 23:56
  Speaker 1: or it can break one of those bonds. And the
• 23:58
  Speaker 1: most damaging thing radiation can do is ionized parts of
• 24:02
  Speaker 1: your body. When it does this, it does things like
• 24:04
  Speaker 1: break up DNA molecules. It acts like a tiny little
• 24:07
  Speaker 1: bullet that shoots through your body and breaks things. So
• 24:10
  Speaker 1: ionizing radiation is very, very dangerous, and that's why it's
• 24:14
  Speaker 1: important to reduce your exposure to ionizing radiation. Now, things
• 24:18
  Speaker 1: like uranium and plutonium give off ionizing radiation, which is
• 24:22
  Speaker 1: very dangerous, and some forms of electromagnetic radiation can have
• 24:27
  Speaker 1: enough energy to ionize. The threshold for ionizing radiation is
• 24:31
  Speaker 1: a little bit fuzzy, depends on the material, etcetera. But
• 24:34
  Speaker 1: it's on the order of magnitude of about ten e
• 24:36
  Speaker 1: v per photon. This is like the binding energy of molecules.
• 24:41
  Speaker 1: And in order to have that much energy of photon
• 24:43
  Speaker 1: has to be in the ultra violet. That's why ultra
• 24:46
  Speaker 1: violet radiation u V rays are bad for you. U
• 24:49
  Speaker 1: V does cause cancer, and that's what you're blocking when
• 24:52
  Speaker 1: you're putting on sunscreen, and that u V light can
• 24:55
  Speaker 1: pass through clouds, which is how you can get a
• 24:56
  Speaker 1: sunburn on a cloudy day. So visible light and everything
• 25:01
  Speaker 1: with a wavelength lower than that, it's not ionizing. It
• 25:04
  Speaker 1: can't cause ionization in your body, and so it's much
• 25:08
  Speaker 1: much safer. Now. Five G is well below the wavelength
• 25:12
  Speaker 1: of even visible light. It's below the infrared. So from
• 25:16
  Speaker 1: the point of view of ionization, the most dangerous thing
• 25:19
  Speaker 1: that radiation can do. Five G is not a concern. Yes,
• 25:22
  Speaker 1: it does have a higher wavelength, and previous generations of
• 25:25
  Speaker 1: cell phones, but it's well below the energy needed to
• 25:29
  Speaker 1: do any damage from an ionizing point of view. But
• 25:33
  Speaker 1: that's not the only way that radiation can damage you.
• 25:36
  Speaker 1: Ionization is not the only thing that it can do.
• 25:38
  Speaker 1: For example, it can deposit energy in your body even
• 25:42
  Speaker 1: without actually ionizing. I mean, this is what an oven does.
• 25:45
  Speaker 1: Right when you cook a turkey in your oven, you're
• 25:48
  Speaker 1: using infrared photons. You're using the heat of the oven
• 25:52
  Speaker 1: to cook that turkey, And yeah, it certainly does damage
• 25:56
  Speaker 1: the turkey. And so you can hurt people with a
• 25:59
  Speaker 1: high intensity of low energy radiation. Right here, we're talking
• 26:05
  Speaker 1: about the intensity and microwave oven uses microwave radiation, which
• 26:10
  Speaker 1: is much much longer in wavelength than ultra violet photons.
• 26:14
  Speaker 1: But it's a very high intensity, and so it can
• 26:16
  Speaker 1: deposit a lot of energy and eventually it can hurt you.
• 26:20
  Speaker 1: So this is the area to focus on from a
• 26:22
  Speaker 1: sort of physics and medical point of view. Can being
• 26:25
  Speaker 1: exposed to a large amount of five G signals do
• 26:29
  Speaker 1: some damage to the human body. Well, it turns out
• 26:32
  Speaker 1: that humans have a sort of built in shield to
• 26:34
  Speaker 1: a lot of this stuff. Most of these photons will
• 26:36
  Speaker 1: actually scatter off of your skin. Your skin is like
• 26:39
  Speaker 1: a shield that will reflect a lot of this energy.
• 26:43
  Speaker 1: The upper layers of your skin are opaque to this
• 26:46
  Speaker 1: kind of photon, so most of it won't even enter
• 26:48
  Speaker 1: your body. There were some very early studies that showed
• 26:51
  Speaker 1: the amount of damage done to tissue based on the
• 26:54
  Speaker 1: frequency and showed the five G was in a range
• 26:57
  Speaker 1: that did more damage, but it neglected to take new
• 27:00
  Speaker 1: count the fact that most of that five G radiation
• 27:02
  Speaker 1: won't even get into your body. But the fact remains
• 27:06
  Speaker 1: that this is a kind of electromagnetic radiation where it's
• 27:09
  Speaker 1: long term exposure has not been studied on the public.
• 27:12
  Speaker 1: We haven't based people and the kinds of radiation that
• 27:15
  Speaker 1: five G will generate for long periods and seeing what
• 27:18
  Speaker 1: would happen. Right, So we just don't know. That doesn't
• 27:21
  Speaker 1: mean we don't have a good guess. We understand the
• 27:23
  Speaker 1: physics of it. We think that it's too low energy
• 27:27
  Speaker 1: to do any ionization damage. We think that the skin
• 27:30
  Speaker 1: is opaque to it and will reflect most of it,
• 27:33
  Speaker 1: and so we think we can do the calculations and
• 27:35
  Speaker 1: it seems totally safe, but we don't have direct evidence.
• 27:39
  Speaker 1: And the folks that are citing studies that show that
• 27:42
  Speaker 1: there's no connection between for example, cell phone towers and
• 27:45
  Speaker 1: cancer are missing the point a little bit because those
• 27:48
  Speaker 1: cell phone towers are using a different frequency than five G.
• 27:52
  Speaker 1: So we don't actually have direct data that shows that
• 27:55
  Speaker 1: five G is safe because it was just invented, right,
• 27:58
  Speaker 1: And so what can we do here? Science can say
• 28:01
  Speaker 1: we don't see a reason why it would be dangerous.
• 28:04
  Speaker 1: We think it will be safe. We do not have
• 28:07
  Speaker 1: direct proof, so we can't conclusively say it's safe. We
• 28:10
  Speaker 1: can't point to studies that prove that it's safe. We
• 28:13
  Speaker 1: can argue and we can make reasonable points that suggest
• 28:16
  Speaker 1: that it will be safe. But in the end, it's
• 28:18
  Speaker 1: a question for policy makers when do you make a
• 28:20
  Speaker 1: decision for how to roll out a new technology which
• 28:23
  Speaker 1: could have lots of benefits for the public, but also
• 28:26
  Speaker 1: every new technology does have some inherent dangers, and in
• 28:29
  Speaker 1: the end, sometimes policy makers do have to make these
• 28:32
  Speaker 1: very difficult decisions knowing they could help people, but they
• 28:35
  Speaker 1: could also potentially hurt people. So that's not something I'm
• 28:39
  Speaker 1: going to comment on because I'm not a policy maker,
• 28:41
  Speaker 1: but I think that the policymakers should at least be
• 28:43
  Speaker 1: informed by the science, and I hope that you guys
• 28:45
  Speaker 1: out there understand the signs of five G. It is
• 28:49
  Speaker 1: a new technology with higher frequency photons, not high enough
• 28:53
  Speaker 1: frequency to do ionizing damage, but the impact of this
• 28:57
  Speaker 1: frequency radiation and very low intensities, how has not been
• 29:00
  Speaker 1: studied on the general public. That doesn't mean that it's
• 29:03
  Speaker 1: caused the pandemic or that it's something that you should
• 29:06
  Speaker 1: worry about. Read more about it, think about it right
• 29:09
  Speaker 1: to your congress people or representatives, or your president or whoever,
• 29:12
  Speaker 1: if you have a deep and passionate opinion about how
• 29:15
  Speaker 1: to balance this question of technology versus safety. All Right,
• 29:19
  Speaker 1: I want to answer another question, but first let's take
• 29:22
  Speaker 1: another break. All right, we're back and I'm answering questions
• 29:38
  Speaker 1: from listeners. We had a question about black holes and
• 29:41
  Speaker 1: hawking radiation. We had a question about wireless cell phone
• 29:45
  Speaker 1: towers and the radiation they emit. And now we have
• 29:48
  Speaker 1: a question about wireless charging. Hi, Daniel, and I was
• 29:53
  Speaker 1: wondering how wireless charging devices work. I don't understand how
• 29:58
  Speaker 1: the battery is charged without a visible input into the device.
• 30:03
  Speaker 1: It's baffling to me. It's like magic. Thanks all right,
• 30:07
  Speaker 1: thank you for this super fun question. Sometimes physics is baffling.
• 30:11
  Speaker 1: It defies our intuition, but you know, the universe works,
• 30:15
  Speaker 1: The universe follows rules. There's always a way to understand
• 30:19
  Speaker 1: what we see and then sometimes to use that understanding
• 30:22
  Speaker 1: to build awesome new technology like wireless charging. And your
• 30:27
  Speaker 1: intuition is that things need a wire because the stuff
• 30:30
  Speaker 1: around you uses wires. Right, either you plug it into
• 30:33
  Speaker 1: the wall or you connect it with a battery, because
• 30:36
  Speaker 1: you're used to a certain kind of way of transmitting energy.
• 30:40
  Speaker 1: You have energy inside a battery or energy coming in
• 30:43
  Speaker 1: the wires, and that's in the form of electrical energy,
• 30:46
  Speaker 1: and those electrons zip along and they deposit that energy
• 30:49
  Speaker 1: into your device, your phone or your camera, or your
• 30:52
  Speaker 1: laptop or your blender or whatever. And that certainly is
• 30:55
  Speaker 1: one way to send electromagnetic energy from one device to
• 30:59
  Speaker 1: another by using the wire, which is essentially just a
• 31:02
  Speaker 1: conductor where the electrons can bump into each other and
• 31:04
  Speaker 1: pass that energy along. However, there are lots of ways
• 31:08
  Speaker 1: to transmit energy, and you can transmit energy wirelessly, right.
• 31:13
  Speaker 1: What is a flashlight. A flashlight is a beam of photons.
• 31:16
  Speaker 1: Those photons have energy. What is a laser A laser
• 31:20
  Speaker 1: concertainly transmit energy, you can use it to heat something
• 31:23
  Speaker 1: up from a distance, right, and those photons can fly
• 31:26
  Speaker 1: through space, even through a vacuum. So conceptually, from a
• 31:31
  Speaker 1: sort of physics point of view, we understand how it's
• 31:33
  Speaker 1: possible for energy to start in one place and get
• 31:36
  Speaker 1: to another place without having a physical connection a wire, right,
• 31:40
  Speaker 1: even across the vacuum of quote unquote empty space. But
• 31:45
  Speaker 1: that doesn't tell us how wireless chargers actually work. How
• 31:49
  Speaker 1: do they get the energy from one device to the
• 31:51
  Speaker 1: other without the two actually being connected. There's not some
• 31:55
  Speaker 1: tiny series of lasers in their zapping energy from one
• 31:58
  Speaker 1: to the other. You certainly don't want your blender to
• 32:01
  Speaker 1: be zapped with lasers. So how does it actually work.
• 32:04
  Speaker 1: The first thing to understand is the whole system is
• 32:06
  Speaker 1: not wireless. It's just like one step there that's wireless.
• 32:09
  Speaker 1: Usually you have like a base which is plugged into
• 32:12
  Speaker 1: the wall, and then you can put your phone on
• 32:14
  Speaker 1: top of that base. It sits on the base and
• 32:17
  Speaker 1: it draws power from the base. And so it's that
• 32:19
  Speaker 1: step that we're gonna try to understand. How can you
• 32:22
  Speaker 1: get energy from the base which is plugged into the
• 32:24
  Speaker 1: wall and getting energy eventually from your power plant, how
• 32:27
  Speaker 1: does it get from that base and into your phone.
• 32:30
  Speaker 1: So this comes from the magic and the beauty of
• 32:33
  Speaker 1: electro magnetism. And to understand how this works, we need
• 32:37
  Speaker 1: to remember that electricity and magnetism feel like two different things, right.
• 32:42
  Speaker 1: Electricity is lightning bolts and electrons, and magnetism is like
• 32:45
  Speaker 1: fridge magnets and levitating trains. But they are actually two
• 32:50
  Speaker 1: parts of the same thing. Maxwell, the Scottish clerk a
• 32:53
  Speaker 1: hundred and fifty years ago, realized that there's a deep
• 32:56
  Speaker 1: symmetry between electricity and magnetism. And you note us this
• 33:00
  Speaker 1: because he noticed that electricity can cause magnetic field to
• 33:03
  Speaker 1: magnetic fields can cause currents, and so that's exactly how
• 33:07
  Speaker 1: it happens. We have two parts of Maxwell's equations working together.
• 33:12
  Speaker 1: So the first part is that when you have an
• 33:14
  Speaker 1: electric current that creates a magnetic field. If you've ever
• 33:18
  Speaker 1: seen an electro magnet, you know this is true. You
• 33:21
  Speaker 1: turn on the current, it goes through coils and those
• 33:24
  Speaker 1: coils create a magnetic field. And every electric engine, for example,
• 33:29
  Speaker 1: has this property inside it. When you turn on the engine,
• 33:32
  Speaker 1: what you're doing is turning on electro magnets inside the engine,
• 33:36
  Speaker 1: which are using the magnet to sort of tug on
• 33:39
  Speaker 1: another part of the engine and get it to move.
• 33:41
  Speaker 1: So the first step is to use currents inside the
• 33:44
  Speaker 1: base station to create a powerful magnetic field. That magnetic field,
• 33:49
  Speaker 1: in turn can cause electrical currents because another part of
• 33:53
  Speaker 1: Maxwell's equations tells us that varying magnetic fields caused electrical currents. Right,
• 33:59
  Speaker 1: So what happens to the base station is you have
• 34:01
  Speaker 1: this current which is going on and off, creating magnetic
• 34:04
  Speaker 1: fields which are on and off, and those magnetic fields
• 34:07
  Speaker 1: then induce a current inside your phone. So inside the
• 34:12
  Speaker 1: phone there has to be some loop, or inside whatever
• 34:14
  Speaker 1: device you're trying to charge, there has to be some loop,
• 34:17
  Speaker 1: and the magnetic fields then induce a current inside that loop.
• 34:21
  Speaker 1: So you have a loop inside the base station where
• 34:23
  Speaker 1: you create a current using power from the wall. That
• 34:26
  Speaker 1: current inside the loop creates a magnetic field, and that
• 34:29
  Speaker 1: magnetic field then creates a current inside a loop of
• 34:32
  Speaker 1: wire in the thing that you want to charge. And
• 34:35
  Speaker 1: so this is a way to transmit the energy from
• 34:38
  Speaker 1: the base station to the phone or whatever it is
• 34:41
  Speaker 1: that you're trying to charge without actually having to have
• 34:44
  Speaker 1: a wire between them. Is essension, like using a magnetic wire.
• 34:48
  Speaker 1: And this only works because there is this symmetry between
• 34:52
  Speaker 1: electricity and magnetism, because currents cause magnetic fields, which cause currents.
• 34:58
  Speaker 1: And the other awesome thing about a symmetry is that
• 35:01
  Speaker 1: it's the reason that we can see anything. What is light?
• 35:05
  Speaker 1: What is a photon? It's a ripple in the electro
• 35:08
  Speaker 1: magnetic field, not the electrical field, not the magnetic field,
• 35:12
  Speaker 1: but the electro magnetic field. And that exists because varying
• 35:16
  Speaker 1: electric fields caused magnetic fields, which caused varying electric fields.
• 35:20
  Speaker 1: So what a photon actually is is a field that
• 35:23
  Speaker 1: slashing back and forth between the electric and the magnetic field.
• 35:28
  Speaker 1: That's what allows it to like pass through the vacuum
• 35:31
  Speaker 1: of space. It supports itself, it propagates itself by going
• 35:35
  Speaker 1: back and forth from electro to magnetic fields. And this
• 35:38
  Speaker 1: was the beautiful inside of Maxwell. He saw these equations
• 35:41
  Speaker 1: and they put them together. He thought, oh, my gosh,
• 35:43
  Speaker 1: light looks just like a wave that's slashing back and
• 35:46
  Speaker 1: forth and moving at some speed. And he did the calculation.
• 35:49
  Speaker 1: He's like, oh, look, it moves at the speed of light.
• 35:52
  Speaker 1: So that was a beautiful moment, sort of in theoretical physics,
• 35:55
  Speaker 1: putting these two pieces together, understanding the symmetry between electric
• 35:59
  Speaker 1: and magnetic field. And it's that same insight that allows
• 36:02
  Speaker 1: us to do inductive powering, to use magnetic induction to
• 36:07
  Speaker 1: take a coil of current and transfer that energy into
• 36:10
  Speaker 1: another coil. Now, this is fascinating if people have done
• 36:14
  Speaker 1: a lot of studies to see, like how far can
• 36:16
  Speaker 1: it work. You're probably most familiar with charging stations at
• 36:19
  Speaker 1: Starbucks where you will get charged from this wireless charging station. Now,
• 36:23
  Speaker 1: the larger the coil inside the base station, the longer
• 36:27
  Speaker 1: the wavelength of this radiation essentially, and the larger the
• 36:30
  Speaker 1: distance that that power can charge. There was a record
• 36:34
  Speaker 1: set in two thousand and seven where somebody was able
• 36:36
  Speaker 1: to charge something two meters away. That's pretty awesome, Right,
• 36:41
  Speaker 1: two meters away is a good distance, not enough that
• 36:44
  Speaker 1: you can like drive around town and keep your phone
• 36:46
  Speaker 1: charge from your house, but it's pretty cool, and it's
• 36:49
  Speaker 1: the kind of thing where people are making strides and
• 36:51
  Speaker 1: eventually there'll be a breakthrough and we'll be able to
• 36:53
  Speaker 1: send power at even greater distances. And you know, your
• 36:57
  Speaker 1: phone is not the only example of this technology. G
• 37:00
  Speaker 1: if anybody out there has an inductive range. It's the
• 37:03
  Speaker 1: kind with coils in it. But those coils don't feel
• 37:06
  Speaker 1: hot because they're not transmitting the energy by making themselves
• 37:09
  Speaker 1: glow really really hot, like the elements inside your oven,
• 37:13
  Speaker 1: which would be giving off infrared radiation. Instead, they're creating
• 37:17
  Speaker 1: magnetic fields, which then cause currents inside a pan that
• 37:21
  Speaker 1: you put on top of the stove, so the pan
• 37:24
  Speaker 1: gets hot, but the surface of the stove itself is
• 37:27
  Speaker 1: not hot because there's no infrared heat passing directly from
• 37:31
  Speaker 1: inside the range to the pan. And then you have
• 37:34
  Speaker 1: this coil inside the range, and that coil has a
• 37:36
  Speaker 1: lot of electricity in it, which is creating a magnetic field,
• 37:40
  Speaker 1: which is creating a current inside your pot, which then
• 37:43
  Speaker 1: turns into heat of the pot. So it's able to
• 37:46
  Speaker 1: transmit this energy and heat of the pot without actually
• 37:49
  Speaker 1: heating up the stuff in between, which is pretty awesome
• 37:52
  Speaker 1: and it means that it's harder to burn yourself. So
• 37:55
  Speaker 1: thanks very much for asking that super fun question about
• 37:58
  Speaker 1: this cool technology. It does seem like magic, but it's
• 38:01
  Speaker 1: actually something that we can understand, and that's the beauty
• 38:04
  Speaker 1: of the universe that amazingly it seems like no matter
• 38:07
  Speaker 1: what happens out there, if you think about it carefully,
• 38:10
  Speaker 1: if we put our collective heads together, we can figure
• 38:13
  Speaker 1: it out. And so, even though there are so many
• 38:16
  Speaker 1: mysteries remaining about the nature of the universe and what's
• 38:19
  Speaker 1: going on inside black holes, and how the universe started
• 38:22
  Speaker 1: and what is everything made out of, at the smallest,
• 38:24
  Speaker 1: tiniest level, all these questions are just the possibilities for
• 38:28
  Speaker 1: new discoveries, the possibility to reveal something new about the
• 38:31
  Speaker 1: universe that we didn't know that would blow the minds
• 38:34
  Speaker 1: of our grandparents. It means that one day our grandchildren
• 38:38
  Speaker 1: will make these discoveries and will blow our minds. So
• 38:41
  Speaker 1: until then, keep thinking about it, keep asking questions, and
• 38:44
  Speaker 1: send us all of your questions. We love to hear
• 38:47
  Speaker 1: your thoughts. Thanks very much. Tune in next time. Thanks
• 38:59
  Speaker 1: for listening. Remember that Daniel and Jorge Explain the Universe
• 39:02
  Speaker 1: is a production of I Heart Radio. For more podcast
• 39:06
  Speaker 1: from my Heart Radio, visit the I Heart Radio Apple
• 39:08
  Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.
• 39:13
  Speaker 1: H