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Why Is There A Universe_ Why Is There Something Rather Than Nothing · Luke's English Podcast

• 0:07
  Speaker 1: Hello, my name's Tim Colson and I'm one of the
• 0:09
  Speaker 1: Science of the Times podcast co-hosts. When I woke up
• 0:14
  Speaker 1: this morning, I do what I often do is I
• 0:15
  Speaker 1: kind of flick through the science news. There was an
• 0:17
  Speaker 1: interesting story on the BBC that said that there was
• 0:20
  Speaker 1: a race between American scientists and Japanese scientists to work
• 0:24
  Speaker 1: out why the universe existed. I kind of thought that
• 0:27
  Speaker 1: was a fascinating story, but it was, as many science
• 0:30
  Speaker 1: stories are in the press, a little bit vague. So
• 0:32
  Speaker 1: I thought I'd explain what's going on in a little
• 0:34
  Speaker 1: bit more detail. So there are two teams, one in
• 0:38
  Speaker 1: America and one in Japan, who are trying to work
• 0:42
  Speaker 1: out tiny little differences between matter and antimatter. Now, most
• 0:49
  Speaker 1: of the everything in the university you see or nearly
• 0:52
  Speaker 1: everything in the university you see is made up of matter.
• 0:57
  Speaker 1: But there is something called antimatter, which is similar to
• 1:00
  Speaker 1: matter in many ways, except it has a different charge. So,
• 1:03
  Speaker 1: for example, something called a proton has a positive charge.
• 1:06
  Speaker 1: whilst an antiproton has a negative charge. And when matter
• 1:09
  Speaker 1: and antimatter come together, they annihilate one another in a
• 1:13
  Speaker 1: huge burst of energy. And theory says that when the
• 1:16
  Speaker 1: universe formed, there should have been equal amounts of matter
• 1:19
  Speaker 1: and antimatter, and therefore we'd have expected them all to
• 1:23
  Speaker 1: explode in a big annihilation, a big bang of energy,
• 1:26
  Speaker 1: and there wouldn't be anything in the universe that would
• 1:28
  Speaker 1: have disappeared. Yet for some reason, a little bit of
• 1:32
  Speaker 1: matter survived, So that either means there was a little
• 1:35
  Speaker 1: bit more matter than antimatter in the universe form, but
• 1:38
  Speaker 1: scientists don't think that's right. Or there's some subtle differences
• 1:41
  Speaker 1: between matter and antimatter that gave matter the upper hand. Indeed,
• 1:47
  Speaker 1: what these two scientific teams are trying to do, one
• 1:50
  Speaker 1: in Japan and one in America, is to try and
• 1:54
  Speaker 1: work out using huge detectors whether a particular type of particle,
• 1:59
  Speaker 1: a neutrino, differs a little bit from an antineutrino in
• 2:04
  Speaker 1: a way that can explain why matter won out in
• 2:06
  Speaker 1: the very, very early universe. Neutrinos and antineutrinos are very
• 2:12
  Speaker 1: tiny particles. They used to be thought to have no
• 2:15
  Speaker 1: mass at all, so no weight in other words, but
• 2:18
  Speaker 1: it turns out that they do weigh a very tiny amount.
• 2:22
  Speaker 1: And when they travel from one location to another, they
• 2:25
  Speaker 1: tend not to interact very much. And that's because they
• 2:29
  Speaker 1: only interact via two forces, gravity and the weak nuclear force.
• 2:33
  Speaker 1: They don't interact by the strong nuclear force or electromagnetism.
• 2:37
  Speaker 1: And that means that they're produced, they're very common, you know,
• 2:40
  Speaker 1: huge numbers of them pass through the Earth every second
• 2:44
  Speaker 1: without hitting anything. They pass through you without causing you
• 2:47
  Speaker 1: any damage. But very occasionally a neutrino will interact with
• 2:51
  Speaker 1: another particle, something like a proton or electron, through the
• 2:57
  Speaker 1: weak nuclear force. And that can be detected, but the
• 3:01
  Speaker 1: detectors to detect that need to be enormous. Now, when
• 3:05
  Speaker 1: neutrinos travel they actually change a little bit and this
• 3:09
  Speaker 1: is kind of something the bbc said but didn't explain
• 3:12
  Speaker 1: why now there are actually three generations of matter and
• 3:16
  Speaker 1: nearly every matter that the matter you see in your
• 3:18
  Speaker 1: everyday life is in the lowest generation the lowest energy
• 3:23
  Speaker 1: state But there are two higher generations where most matter
• 3:27
  Speaker 1: doesn't exist in that state for very long. When neutrinos travel,
• 3:33
  Speaker 1: they might start out as sort of an electron neutrino.
• 3:37
  Speaker 1: And then through quantum processes, they might flip to being
• 3:41
  Speaker 1: more muon neutrino or the third generation. So they kind
• 3:47
  Speaker 1: of flip between these states, which is kind of quite unusual.
• 3:51
  Speaker 1: And there's some evidence that, in fact, the rate that
• 3:55
  Speaker 1: they oscillate, it's known as neutrino oscillation, that the rate
• 3:58
  Speaker 1: between they oscillate between these states differs a little bit
• 4:03
  Speaker 1: between neutrinos and antineutrinos. And what the scientists are hoping
• 4:09
  Speaker 1: to find is to actually characterize whether that difference is real,
• 4:14
  Speaker 1: whether that difference is sufficient to explain why matter won
• 4:19
  Speaker 1: out over antimatter in the early Now, the Japanese team
• 4:23
  Speaker 1: is a little bit ahead. They're detectors, so they're experimental setup.
• 4:29
  Speaker 1: It should start running in the next couple of years.
• 4:31
  Speaker 1: while it's going to be a few more years before
• 4:33
  Speaker 1: the American team sets up. Now, both teams might be
• 4:38
  Speaker 1: able to work out this difference. The Americans team detector
• 4:42
  Speaker 1: is a little bit different from the Japanese team. So
• 4:44
  Speaker 1: the Americans are saying that even if the Japanese get
• 4:47
  Speaker 1: there first, their experiment will still be valuable because it's
• 4:50
  Speaker 1: going to tell them a load of information that the
• 4:52
  Speaker 1: Japanese team can't detect. And I'm sure that's true. So
• 4:56
  Speaker 1: exciting times, but we're not yet at any point to
• 5:00
  Speaker 1: explain why there is something rather than nothing. But who knows,
• 5:04
  Speaker 1: perhaps some hints about that might appear in the next
• 5:07
  Speaker 1: few years. Let's hope so. Hope that little explainer was useful.
• 5:11
  Speaker 1: Thank you.