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The big bang, the story of everything ...
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time, the universe, us.
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The big bang, one, has a cool name,
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and two, it's the history of our universe.
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This is it. It's all of us.
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It's all things.
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That's the traditional view,
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but is it right?
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More and more scientists aren't sure.
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In the old, outdated big bang theory,
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our universe just popped into existence from nothing.
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We talk about it as the beginning of the universe,
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but what it really is is the end of our understanding.
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Astronomers are ripping up the old rules,
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but that creates new problems.
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How can we possibly say that universe expanded
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faster than the speed of light?
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But are they asking questions with no answers?
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What was the origin?
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Is there even a sense to asking, "was there a time before time?"
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We don't know. We got nothing, folks.
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Well, we got some things, but it's tough.
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It's tough.
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It doesn't tell us what happened, really,
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at the beginning.
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This is still an absolute puzzle.
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So just how did it all start?
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The big bang theory is a good story, but is it true?
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captions paid for by discovery communications
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to begin at the beginning ...
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no space, no time,
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everything in the known universe
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compressed into a dot smaller than an atom.
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Suddenly, out of this, the universe expands.
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Stars and galaxies form,
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creating the cosmos we see today.
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The story of our universe starts with a big bang, or does it?
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So the big bang is the observed truth,
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but there are details that haven't been quite worked out.
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There are a lot of things that may have happened.
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It's just one explanation.
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Science isn't about being right all the time.
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It's about being wrong,
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and we could absolutely be wrong about a major component
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in our understanding of the universe.
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We're putting one of science's
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greatest stories to the test.
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The big bang sure sounds like an explosion, but was it?
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An explosion is a sudden release of energy from one point
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usually generating light,
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heat, pressure,
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and a bang.
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But did the big bang even explode?
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When you hear the term bang, you think of a noise,
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but you have to realize that it's sound waves
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propagating through air.
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So after the big bang, there's no air.
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There was no air.
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There's no way to hear anything, so in that sense, it was silent.
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So the big bang didn't bang,
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but to make the universe,
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it must've pushed out stuff,
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lots of stuff.
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Every explosion has an ignition point.
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What about the big bang?
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So if you were to only think of the big bang as an explosion,
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you would very rightly ask,
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"well, where's the center of that explosion?
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Where is the center of the universe?"
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There was no central point.
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There's nowhere in the sky you can point and say,
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"that's where the big bang was."
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The big bang is everything.
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The big bang happened here, where I'm sitting.
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The big bang happened on the other side of the planet.
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The big bang happened in the Andromeda galaxy.
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The big bang occurred throughout
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the universe simultaneously.
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During an explosion,
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debris fires out from the center.
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This debris spreads out unevenly,
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with different-sized pieces
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landing at different distances from the blast center,
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but did the big bang shoot material out
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in this explosive manner?
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For clues, we need to search the night sky.
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One of the things that's really very striking about the universe
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when you simply take a telescope
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and start looking in different directions is that it,
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roughly speaking, looks the same in all directions.
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Although the universe is peppered with individual
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galaxies and galaxy clusters,
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the big picture is what astronomers call homogeneous.
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When we say the universe is homogeneous,
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it means it's almost exactly the same on very large scales
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with very, very little differences.
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It's perfectly smooth.
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If we believe the classic big bang story,
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the same amount of material was shot out
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over the same distance in all directions.
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Our smooth, homogeneous universe
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doesn't appear to be the result of what we know as an explosion.
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It wasn't big, and it wasn't a bang.
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The big bang was not an explosion like a grenade
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or a bomb or dynamite
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where there is material rushing out from a common center.
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It's not like there's a ring of galaxies
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that came out from some explosion.
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A firecracker explosion is
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triggered by a fuse,
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so what set off the big bang?
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What I would say is there's no such thing as,
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"what triggered the big bang?"
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You know, we tend to think when something happens,
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when there's an effect, there was a cause, right?
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There was something that made it happen,
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but here, we're talking about the whole universe.
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There's nothing outside the universe
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to bring it into existence.
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The science is clear.
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The universe did not start with an explosion,
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but if there was no bang,
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then how did everything start so small and get so big?
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The young universe, we do understand,
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and that old contemporary universe, we also understand.
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We've stitched together this story
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where we don't fully understand
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the first few paragraphs of the story,
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but we know the rest of the book.
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How can we get to the bottom of the big bang story
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when we can't even read the first page of the book?
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The only hope we have is to search back in time,
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line by line.
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One of the amazing things about being a cosmologist
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is that telescopes are time machines.
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It takes a while for light to get here,
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so if we look farther out into space,
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we're really looking back into the history of the universe,
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and that's amazing.
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The first clues to unraveling the big bang mystery
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came with the introduction of advanced telescopes
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in the 1920s.
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Edwin hubble was studying the light
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coming from distant galaxies,
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and what he realized was the more distant the galaxy was,
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the more reddened the light was.
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Why should that be?
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Well, it turns out that light reddens
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if a galaxy is moving away from us.
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It's called the red shift.
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So what he discovered was pretty much every galaxy in the sky
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was moving directly away from the milky way.
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This was truly one of science's landmark moments.
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Hubble had proved one of the basic principles
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of the big bang story ...
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our universe is continuously expanding.
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There was only one conclusion to draw.
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If you extrapolate that back in time,
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it looks like everything was coming
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from one point at one time.
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That's the big bang.
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Hubble's discovery grabbed the headlines,
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but the idea of an expanding universe
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had been proposed two years earlier
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by a Belgian priest and physicist.
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The real idea of the big bang comes from georges lemaître.
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He realized that if you ran time backwards,
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back to the beginning of time,
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maybe everything coalesced into a single atom,
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the primeval atom.
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Lemaître believed the infant universe
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was extremely small and dense,
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squeezed into a single point ...
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the primeval atom.
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Later, scientists would define this point
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as an infinite entity called a singularity,
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but there's a problem.
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The singularity and the laws of physics don't mix.
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It may be one infinitely small point,
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but it causes some impossibly big problems.
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The big bang ... for almost a century,
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it's been science's leading account of how everything began.
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but there was no explosion,
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no bang, and it wasn't big.
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In fact, the father of the big bang, georges lemaître,
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claimed everything originated from one tiny point
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he called the primeval atom.
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I think one of the hardest things to grasp
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about the idea of the big bang is that everything you see,
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everything you've ever known, everybody, every house,
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every tree, every planet, every moon, every star,
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every galaxy in the entire universe at some point,
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13.8 billion years ago,
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was compressed down into a tiny little dot.
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In fact, far smaller than a tiny dot,
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infinitely small, a point called a singularity,
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and this singularity has been causing astronomers headaches
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for decades.
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It's all because of one word ... infinite.
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As soon as you start getting the word infinity,
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things are infinitely larger, infinitely small.
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In physics, it means that you don't understand everything.
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Einstein's general relativity predicts
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the theoretical existence of singularities,
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but in practice, a singularity
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is where our current laws of physics break down.
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We do not understand singularities.
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These are some of the theoretical questions
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that are real conundrums,
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and people are trying to figure out what to do.
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The universe is telling us something is going on here
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that we don't understand quite yet with our math.
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Our mathematics are incomplete.
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This is a sign that general relativity
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is not up to the task of describing the earliest,
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earliest moments of the universe.
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General relativity predicts singularities,
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but in reality, it doesn't work
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when things are really tiny.
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Einstein's picture of general relativity
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is incredibly successful
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at describing the motion of planets around the sun,
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the bending of light around massive objects,
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the growth and expansion of the universe itself,
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but it breaks down when gravity gets too strong
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and gets too small.
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General relativity may not be the best tool
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for understanding the origin of the universe.
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Say, for example,
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you want to weigh some spices in your kitchen.
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You can use a kitchen scale.
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That works really fine, but now say, on the other hand,
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you wish to weigh your truck.
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That's just not the right tool for it.
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So forget relativity.
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Maybe another fundamental branch of theoretical physics
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can help out ... quantum mechanics.
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This deals with the small, the very small,
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but what about the infinitely small?
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Can quantum mechanics prove the existence of a singularity?
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General relativity seems to say that singularities exist.
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They're a very straightforward prediction
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of general relativity.
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That doesn't fit well with what quantum mechanics says.
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Quantum mechanics tends to fuzz things out.
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It doesn't really like singularities.
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In some theories of quantum mechanics,
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the science of the small,
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there's a limit to how small you can go.
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For example, I'm not gonna be able to fold this paper
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more than seven times.
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One, two, three, four,
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I'm feeling good.
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Five, oh, man, six, can I do it?
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Can I do it? Can I break the laws of physics?
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No, I can't.
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There's a limit. I just can't go past it.
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You can't keep folding paper or space
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into smaller and smaller fragments,
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and according to most laws of quantum mechanics,
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you can't have anything infinitely small
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and infinitely dense.
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Singularities seem to be doomed.
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So is the big bang story wrong,
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or are we just too dumb to work it out?
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Our laws of physics are our best attempts
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00:13:57,503 --> 00:14:00,570
to model with mathematics
268
00:14:00,572 --> 00:14:04,174
all of our observations of the universe.
269
00:14:04,176 --> 00:14:06,777
The universe doesn't care what we think.
270
00:14:06,779 --> 00:14:09,647
The universe doesn't care how we understand it.
271
00:14:09,649 --> 00:14:11,182
This is just our attempts
272
00:14:11,184 --> 00:14:14,251
to explain the behavior that we see,
273
00:14:14,253 --> 00:14:16,954
and the earliest moments of the big bang
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00:14:16,956 --> 00:14:22,726
is a big example of where our understanding falls short.
275
00:14:27,467 --> 00:14:29,800
Maybe the answer lies in a combination
276
00:14:29,802 --> 00:14:33,270
of general relativity and quantum mechanics.
277
00:14:33,272 --> 00:14:34,673
All right, guys. Go ahead.
278
00:14:34,675 --> 00:14:35,739
But they won't play ball.
279
00:14:35,741 --> 00:14:37,407
One, two, three. Deuce!
280
00:14:37,409 --> 00:14:38,609
-Who's house? -Our house.
281
00:14:38,611 --> 00:14:40,144
-Who's house? -Our house.
282
00:14:40,146 --> 00:14:42,879
-One, two, three. -Go usc!
283
00:14:42,881 --> 00:14:44,148
-Whoo! -Whoo!
284
00:14:44,150 --> 00:14:46,483
Sutter: Imagine the rules of quantum mechanics
285
00:14:46,485 --> 00:14:49,353
are like the rules that lacrosse players
286
00:14:49,355 --> 00:14:51,555
might use to play their game,
287
00:14:51,557 --> 00:14:53,891
and the rules of general relativity
288
00:14:53,893 --> 00:14:55,959
are the rules that baseball players
289
00:14:55,961 --> 00:14:57,895
would use to play their game.
290
00:14:57,897 --> 00:15:01,432
If you're just watching a baseball game
291
00:15:01,434 --> 00:15:03,433
then they're just following the rules of baseball
292
00:15:03,435 --> 00:15:04,768
or general relativity.
293
00:15:04,770 --> 00:15:06,636
If you're just watching a lacrosse game,
294
00:15:06,638 --> 00:15:09,707
you're watching the rules of lacrosse play out,
295
00:15:09,709 --> 00:15:12,243
you're watching the rules of quantum mechanics.
296
00:15:12,245 --> 00:15:14,178
But if you take one team from lacrosse
297
00:15:14,180 --> 00:15:15,779
and one team from baseball
298
00:15:15,781 --> 00:15:19,517
and put them together and ask them to start playing,
299
00:15:19,519 --> 00:15:21,986
they don't even know how to interact with each other.
300
00:15:21,988 --> 00:15:27,457
It's fundamentally different rules that simply don't connect.
301
00:15:27,459 --> 00:15:29,660
Each of these pillars of modern science,
302
00:15:29,662 --> 00:15:31,929
quantum mechanics and general relativity,
303
00:15:31,931 --> 00:15:35,933
are wonderful in their domain,
304
00:15:35,935 --> 00:15:39,870
but when we try to marry them, which is what we need to do
305
00:15:39,872 --> 00:15:42,539
to describe the earliest moments of the universe,
306
00:15:42,541 --> 00:15:44,809
it all goes haywire.
307
00:15:44,811 --> 00:15:46,343
Perhaps both teams playing with
308
00:15:46,345 --> 00:15:48,678
a unified set of rules
309
00:15:48,680 --> 00:15:52,416
will shed some light on the big bang.
310
00:15:52,418 --> 00:15:55,352
Merging together quantum mechanics and general relativity
311
00:15:55,354 --> 00:15:56,821
is the gold standard.
312
00:15:56,823 --> 00:15:58,290
It's what every theoretical physicist
313
00:15:58,292 --> 00:16:00,156
would really love to do in the modern age.
314
00:16:00,158 --> 00:16:01,758
We haven't done it yet.
315
00:16:01,760 --> 00:16:04,628
We have ideas, so when I say, "we haven't done it yet,"
316
00:16:04,630 --> 00:16:06,964
we don't agree on what the right idea is.
317
00:16:06,966 --> 00:16:11,969
What will ultimately reconcile quantum mechanics with gravity?
318
00:16:11,971 --> 00:16:16,240
Is there even a reconciliation between them?
319
00:16:16,242 --> 00:16:17,708
What do we need?
320
00:16:17,710 --> 00:16:21,912
Do we need more surprising, more powerful observations,
321
00:16:21,914 --> 00:16:24,047
new data that we weren't expecting,
322
00:16:24,049 --> 00:16:28,519
another genius or 1,000 geniuses to come along
323
00:16:28,521 --> 00:16:32,455
and find the route through the mathematics to marry it?
324
00:16:32,457 --> 00:16:37,260
It's probably all of the above.
325
00:16:37,262 --> 00:16:38,729
So a major premise of
326
00:16:38,731 --> 00:16:42,867
the big bang story remains unproven,
327
00:16:42,869 --> 00:16:44,467
but what about monsignor lemaître's
328
00:16:44,469 --> 00:16:47,204
other assertions?
329
00:16:47,206 --> 00:16:50,140
Was the infant universe, the primeval atom,
330
00:16:50,142 --> 00:16:52,475
intensely hot,
331
00:16:52,477 --> 00:16:55,546
and if so, just how hot was it?
332
00:17:16,035 --> 00:17:17,368
The story of the big bang
333
00:17:17,370 --> 00:17:19,369
is based on the discovery
334
00:17:19,371 --> 00:17:22,973
that the universe is continuously expanding,
335
00:17:22,975 --> 00:17:25,041
and if we go back in time,
336
00:17:25,043 --> 00:17:28,646
this leads to one inescapable conclusion.
337
00:17:30,983 --> 00:17:32,316
so if you run the clock backwards
338
00:17:32,318 --> 00:17:34,117
and let the universe get younger,
339
00:17:34,119 --> 00:17:35,653
it'll get smaller and smaller and smaller,
340
00:17:35,655 --> 00:17:38,989
and then everything is basically compressed into one point.
341
00:17:38,991 --> 00:17:40,390
The big bang story claims
342
00:17:40,392 --> 00:17:44,863
this point was infinitely small,
343
00:17:44,865 --> 00:17:47,365
but scientists have not been able to prove
344
00:17:47,367 --> 00:17:50,667
the existence of such singularities.
345
00:17:50,669 --> 00:17:53,203
In our universe, we see all galaxies
346
00:17:53,205 --> 00:17:57,407
receding from all other galaxies on average.
347
00:17:57,409 --> 00:18:01,878
Imagine if you were looking at trains leaving a station.
348
00:18:01,880 --> 00:18:03,614
If you ran the clock backwards,
349
00:18:03,616 --> 00:18:07,017
the trains would converge to the same station.
350
00:18:07,019 --> 00:18:10,087
Now, did these trains come from the same station?
351
00:18:10,089 --> 00:18:11,288
Probably.
352
00:18:11,290 --> 00:18:14,224
Did they come from the exact same platform?
353
00:18:14,226 --> 00:18:15,692
Probably not.
354
00:18:15,694 --> 00:18:18,629
You can't fit all the trains onto the same platform.
355
00:18:18,631 --> 00:18:21,765
But while physicists can't prove everything came
356
00:18:21,767 --> 00:18:25,235
from an infinitely small and dense singularity,
357
00:18:25,237 --> 00:18:27,838
they're convinced the observable universe
358
00:18:27,840 --> 00:18:30,774
did expand from one small point,
359
00:18:30,776 --> 00:18:35,912
and this point was incredibly dense and incredibly hot.
360
00:18:35,914 --> 00:18:37,581
Imagine that you and a bunch of friends
361
00:18:37,583 --> 00:18:39,583
are in a very large room,
362
00:18:39,585 --> 00:18:41,985
and you're all hanging out, and it all seems normal,
363
00:18:41,987 --> 00:18:43,587
but now you're all cramped together
364
00:18:43,589 --> 00:18:45,589
in a very small elevator,
365
00:18:45,591 --> 00:18:47,391
and it starts to feel much warmer
366
00:18:47,393 --> 00:18:49,593
because you're interchanging all of this heat.
367
00:18:49,595 --> 00:18:51,262
It's sort of like that in the early universe.
368
00:18:51,264 --> 00:18:52,897
Everything is smashed together.
369
00:18:52,899 --> 00:18:56,066
Everything is very hot.
370
00:18:56,068 --> 00:18:58,402
It makes sense theoretically that this period
371
00:18:58,404 --> 00:19:03,073
was intensely hot, but how do you prove it?
372
00:19:03,075 --> 00:19:06,677
How do you take the temperature of the early universe,
373
00:19:06,679 --> 00:19:11,415
which began 13.8 billion years ago?
374
00:19:11,417 --> 00:19:14,485
You can't, but you can take the temperature
375
00:19:14,487 --> 00:19:17,888
of the coldest part of the universe now.
376
00:19:17,890 --> 00:19:19,756
So if you go away from all the stars
377
00:19:19,758 --> 00:19:21,291
and get away from all the galaxies,
378
00:19:21,293 --> 00:19:25,028
you might think space was infinitely cold, absolute zero,
379
00:19:25,030 --> 00:19:26,963
but it turns out it's not.
380
00:19:26,965 --> 00:19:28,766
Empty space has a temperature
381
00:19:28,768 --> 00:19:34,504
of roughly 455 degrees fahrenheit below zero,
382
00:19:34,506 --> 00:19:38,108
5 degrees higher than absolute zero.
383
00:19:38,110 --> 00:19:43,380
Where did these mysterious extra 5 degrees come from?
384
00:19:43,382 --> 00:19:47,050
Big bang believers thought they had the answer.
385
00:19:47,052 --> 00:19:49,586
They claimed this faint trace of heat
386
00:19:49,588 --> 00:19:51,922
was left over from the incredibly hot
387
00:19:51,924 --> 00:19:54,257
infant universe.
388
00:19:54,259 --> 00:19:56,860
Getting the proof took decades,
389
00:19:56,862 --> 00:20:02,266
but it came in 1964 by pure accident.
390
00:20:02,268 --> 00:20:04,868
Penzias and Wilson were bell labs engineers,
391
00:20:04,870 --> 00:20:06,069
and they were given an assignment
392
00:20:06,071 --> 00:20:09,540
to measure certain radio signals
393
00:20:09,542 --> 00:20:12,476
for the idea of sending wireless signals via telephones,
394
00:20:12,478 --> 00:20:14,545
so rural areas could have telephone.
395
00:20:14,547 --> 00:20:16,346
They used a radio antenna
396
00:20:16,348 --> 00:20:18,949
shaped like a giant horn.
397
00:20:18,951 --> 00:20:21,886
The problem was, no matter where they pointed this horn,
398
00:20:21,888 --> 00:20:23,620
they kept hearing kind of a static,
399
00:20:23,622 --> 00:20:27,891
just a radio noise coming from every direction.
400
00:20:27,893 --> 00:20:31,028
Sutter: And they thought, "okay. Maybe it's a satellite,"
401
00:20:31,030 --> 00:20:33,964
but it didn't match up with any satellite positions.
402
00:20:33,966 --> 00:20:35,765
There's a nearby army base,
403
00:20:35,767 --> 00:20:37,234
and they called up the army base and said,
404
00:20:37,236 --> 00:20:39,403
"hey. Are you broadcasting at this frequency?"
405
00:20:39,405 --> 00:20:41,304
And they said, "no. We're not."
406
00:20:41,306 --> 00:20:44,040
Thought, "maybe it's pigeon poop."
407
00:20:44,042 --> 00:20:45,775
Well, you know, there are these pigeons
408
00:20:45,777 --> 00:20:47,578
nesting inside the antenna,
409
00:20:47,580 --> 00:20:51,248
and their droppings are creating this noise in your telescope.
410
00:20:51,250 --> 00:20:53,051
So they actually went inside and scraped out
411
00:20:53,053 --> 00:20:54,385
all these pigeon droppings,
412
00:20:54,387 --> 00:20:57,522
but no matter what they did, the noise remained.
413
00:20:57,524 --> 00:21:01,725
They tried everything they could to remove this background noise,
414
00:21:01,727 --> 00:21:04,661
and they finally realized it was coming from the sky.
415
00:21:04,663 --> 00:21:07,131
It was real.
416
00:21:07,133 --> 00:21:09,933
What they were hearing was not radio waves
417
00:21:09,935 --> 00:21:12,736
but a different form of radiation ...
418
00:21:12,738 --> 00:21:16,874
microwaves, a heat signature left over from the big bang.
419
00:21:20,546 --> 00:21:25,083
they had discovered the cosmic microwave background,
420
00:21:25,085 --> 00:21:29,819
a ghostly snapshot of the early universe.
421
00:21:29,821 --> 00:21:32,289
Different colors highlight subtle variations
422
00:21:32,291 --> 00:21:34,424
in temperature.
423
00:21:34,426 --> 00:21:36,493
The cooler blue areas will develop
424
00:21:36,495 --> 00:21:40,297
to form stars and galaxies.
425
00:21:40,299 --> 00:21:43,500
The warmer orange areas will eventually make up
426
00:21:43,502 --> 00:21:47,370
the vastness of intergalactic space.
427
00:21:47,372 --> 00:21:49,239
Sutter: The cosmic microwave background
428
00:21:49,241 --> 00:21:53,309
is a literal baby picture of our universe.
429
00:21:53,311 --> 00:21:56,980
It's the equivalent of a picture of you
430
00:21:56,982 --> 00:21:59,917
when you were seven seconds old.
431
00:21:59,919 --> 00:22:02,653
We can date the cosmic microwave background
432
00:22:02,655 --> 00:22:07,391
to 380,000 years after the big bang.
433
00:22:07,393 --> 00:22:09,459
The temperature here is estimated
434
00:22:09,461 --> 00:22:12,797
to be 5,000 degrees fahrenheit,
435
00:22:12,799 --> 00:22:16,800
but how hot was the big bang?
436
00:22:16,802 --> 00:22:20,938
As we run the clock backwards, the universe gets smaller,
437
00:22:20,940 --> 00:22:26,276
and the temperature increases.
438
00:22:26,278 --> 00:22:27,677
We know what the temperature of the cosmic
439
00:22:27,679 --> 00:22:29,813
microwave background was, but prior to that time,
440
00:22:29,815 --> 00:22:32,883
we know the universe was getting smaller and smaller and smaller,
441
00:22:32,885 --> 00:22:36,753
and therefore it had to get hotter and hotter and hotter.
442
00:22:36,755 --> 00:22:40,958
But can we find out how hot?
443
00:22:40,960 --> 00:22:44,027
In the early universe, it was much smaller, denser,
444
00:22:44,029 --> 00:22:46,630
and hotter than it is today, and in fact,
445
00:22:46,632 --> 00:22:51,634
it was so hot it could fuse hydrogen into helium.
446
00:22:51,636 --> 00:22:54,104
25% of the mass in the early universe
447
00:22:54,106 --> 00:22:58,442
is fused into helium in this timescale of just a few minutes,
448
00:22:58,444 --> 00:23:00,510
so it's trillions and trillions of times
449
00:23:00,512 --> 00:23:03,447
more than the amount of fusion that's going on in the sun.
450
00:23:08,587 --> 00:23:10,720
Extremely high temperatures are required
451
00:23:10,722 --> 00:23:13,457
to fuse hydrogen into helium.
452
00:23:13,459 --> 00:23:17,661
Scientists estimate fusion started 100 seconds
453
00:23:17,663 --> 00:23:19,130
after the big bang,
454
00:23:19,132 --> 00:23:24,267
when temperatures reached 1 billion degrees fahrenheit.
455
00:23:24,269 --> 00:23:26,336
During the very first fractions
456
00:23:26,338 --> 00:23:29,473
of the very first second of the big bang,
457
00:23:29,475 --> 00:23:32,409
some estimate the temperature could have reached
458
00:23:32,411 --> 00:23:38,281
250 million trillion trillion degrees fahrenheit,
459
00:23:38,283 --> 00:23:41,418
but what sparked this massive release of energy
460
00:23:41,420 --> 00:23:45,088
here at the birth of the big bang?
461
00:23:45,090 --> 00:23:48,759
The initial moments of our universe
462
00:23:48,761 --> 00:23:51,160
are a source of frustration
463
00:23:51,162 --> 00:23:53,297
because it'd be really nice to know that,
464
00:23:53,299 --> 00:23:55,765
but also a source of curiosity.
465
00:23:55,767 --> 00:23:57,968
This is the frontiers of physics.
466
00:23:57,970 --> 00:24:00,570
This is where we're really pushing things
467
00:24:00,572 --> 00:24:02,105
to try to understand
468
00:24:02,107 --> 00:24:05,909
the fundamental aspects of reality.
469
00:24:05,911 --> 00:24:08,579
But even if we could back up the big bang story
470
00:24:08,581 --> 00:24:13,249
by proving the way everything came from a tiny hot point,
471
00:24:13,251 --> 00:24:15,385
there's still another problem.
472
00:24:15,387 --> 00:24:20,691
Where did everything that made up that tiny point come from?
473
00:24:20,693 --> 00:24:22,258
You can't get something from nothing, right?
474
00:24:22,260 --> 00:24:24,662
We all know that, except it looks like
475
00:24:24,664 --> 00:24:26,396
we got everything from nothing.
476
00:24:26,398 --> 00:24:29,532
The entire universe seems to have appeared out of nowhere.
477
00:24:29,534 --> 00:24:30,801
How can that work?
478
00:24:42,748 --> 00:24:44,414
The big bang ...
479
00:24:44,416 --> 00:24:48,685
no space, total darkness, nothing.
480
00:24:51,690 --> 00:24:57,027
suddenly, the universe sparks into life.
481
00:24:57,029 --> 00:24:59,029
Really?
482
00:24:59,031 --> 00:25:03,433
Surely, everyone knows you can't get something from nothing.
483
00:25:06,104 --> 00:25:08,238
it's really the ultimate question.
484
00:25:08,240 --> 00:25:10,907
How did the universe come into being?
485
00:25:10,909 --> 00:25:14,111
And the thing is we don't want just everything to come nothing.
486
00:25:14,113 --> 00:25:16,580
It seems like a trick, but here we are.
487
00:25:16,582 --> 00:25:19,515
We exist, so something must've happened,
488
00:25:19,517 --> 00:25:22,985
and we just don't understand the physics of it yet.
489
00:25:22,987 --> 00:25:26,323
This is one of the big open questions in cosmology,
490
00:25:26,325 --> 00:25:28,591
the origin of the universe,
491
00:25:28,593 --> 00:25:32,529
and I think that people have variously said stuff like,
492
00:25:32,531 --> 00:25:34,264
"oh, the universe has come from nothing."
493
00:25:34,266 --> 00:25:35,799
Like, ta-da!
494
00:25:35,801 --> 00:25:41,738
Now there's a universe, but remember, we don't have data
495
00:25:41,740 --> 00:25:44,541
about the earliest moments of the universe.
496
00:25:44,543 --> 00:25:49,545
We don't know what was going on.
497
00:25:49,547 --> 00:25:51,615
We're struggling in the dark.
498
00:25:51,617 --> 00:25:54,284
To get insight into what may have happened
499
00:25:54,286 --> 00:25:55,786
before the big bang,
500
00:25:55,788 --> 00:25:58,822
that period of apparent nothingness,
501
00:25:58,824 --> 00:26:01,824
physicists look to empty space,
502
00:26:01,826 --> 00:26:04,961
but does empty really mean
503
00:26:04,963 --> 00:26:08,432
there's absolutely nothing there?
504
00:26:08,434 --> 00:26:11,167
It's not that there's something coming from nothing
505
00:26:11,169 --> 00:26:14,905
because that old-fashioned idea of nothing just doesn't apply
506
00:26:14,907 --> 00:26:17,907
to what we think of as empty space.
507
00:26:17,909 --> 00:26:22,445
It turns out empty space is far from empty.
508
00:26:22,447 --> 00:26:26,516
The vacuum of space is really a writhing sea awash
509
00:26:26,518 --> 00:26:31,521
with charged quantum particles and electromagnetic fields.
510
00:26:31,523 --> 00:26:35,324
The vacuum of space itself can be a very dynamic thing.
511
00:26:35,326 --> 00:26:37,727
Matter can spontaneously appear out of the vacuum
512
00:26:37,729 --> 00:26:39,996
and then spontaneously annihilate.
513
00:26:39,998 --> 00:26:43,133
The vacuum is full of particles and antiparticles
514
00:26:43,135 --> 00:26:45,335
that are whizzing into existence
515
00:26:45,337 --> 00:26:48,404
and then disappearing, colliding with each other.
516
00:26:48,406 --> 00:26:51,007
Space is full of virtual particles
517
00:26:51,009 --> 00:26:54,010
popping in and out of existence.
518
00:26:54,012 --> 00:26:56,012
And there's no question that they're real.
519
00:26:56,014 --> 00:26:57,748
Their effects are absolutely visible.
520
00:26:57,750 --> 00:27:02,619
We can see them.
521
00:27:02,621 --> 00:27:06,423
In extreme physics, things can get strange.
522
00:27:06,425 --> 00:27:09,693
Maybe nothing is something after all.
523
00:27:12,365 --> 00:27:14,631
If empty space contains particles
524
00:27:14,633 --> 00:27:17,033
that apparently come from nothing,
525
00:27:17,035 --> 00:27:19,235
could some sort of similar process
526
00:27:19,237 --> 00:27:23,239
have triggered the big bang?
527
00:27:23,241 --> 00:27:26,242
The quantum vacuum itself
528
00:27:26,244 --> 00:27:30,079
can randomly, spontaneously,
529
00:27:30,081 --> 00:27:32,983
without any input just ...
530
00:27:32,985 --> 00:27:36,720
have a lot of energy, perhaps enough energy
531
00:27:36,722 --> 00:27:39,656
to spark something that we would call a big bang.
532
00:27:43,662 --> 00:27:45,595
There are many speculative theories
533
00:27:45,597 --> 00:27:48,265
about the origin of the universe,
534
00:27:48,267 --> 00:27:51,801
but is its sudden appearance out of nothingness
535
00:27:51,803 --> 00:27:54,572
the only trick it pulled off?
536
00:27:54,574 --> 00:27:57,741
It also made matter from energy.
537
00:27:57,743 --> 00:28:01,544
The universe is full of galaxies, stars, planets,
538
00:28:01,546 --> 00:28:03,012
and comets.
539
00:28:03,014 --> 00:28:07,016
Where did they all come from?
540
00:28:07,018 --> 00:28:09,952
According to the big bang narrative ... from one tiny dot.
541
00:28:09,954 --> 00:28:11,254
When the universe began,
542
00:28:11,256 --> 00:28:13,356
there was actually no room for matter at all.
543
00:28:13,358 --> 00:28:15,158
The temperature was so high.
544
00:28:15,160 --> 00:28:19,029
The spaces were so compressed that matter couldn't exist.
545
00:28:19,031 --> 00:28:20,896
So how did the universe manage
546
00:28:20,898 --> 00:28:25,301
to become full of matter?
547
00:28:25,303 --> 00:28:28,972
In the primeval atom, there was no room for matter,
548
00:28:28,974 --> 00:28:32,775
but it was crammed full of energy,
549
00:28:32,777 --> 00:28:34,511
and as Einstein tells us,
550
00:28:34,513 --> 00:28:39,716
all we need to create matter is energy.
551
00:28:39,718 --> 00:28:42,519
According to e equals mc squared,
552
00:28:42,521 --> 00:28:47,824
energy and matter are interchangeable.
553
00:28:47,826 --> 00:28:51,394
Einstein taught us with special relativity
554
00:28:51,396 --> 00:28:56,733
that energy and matter are two sides of the same coin.
555
00:28:56,735 --> 00:28:59,469
You can convert matter into energy by,
556
00:28:59,471 --> 00:29:02,805
say, blowing something up.
557
00:29:02,807 --> 00:29:03,873
The most fearsome example
558
00:29:03,875 --> 00:29:06,343
of converting matter into energy
559
00:29:06,345 --> 00:29:09,479
was the atomic bomb, developed in the 1940s.
560
00:29:14,486 --> 00:29:19,289
but with the big bang, this process was reversed.
561
00:29:19,291 --> 00:29:23,293
Energy created matter,
562
00:29:23,295 --> 00:29:26,696
matter that expanded out and out
563
00:29:26,698 --> 00:29:31,301
to fill a whole universe,
564
00:29:31,303 --> 00:29:33,103
and in cosmic terms,
565
00:29:33,105 --> 00:29:38,174
the universe where matter would develop grew remarkably fast.
566
00:29:38,176 --> 00:29:40,044
Right after the universe was born,
567
00:29:40,046 --> 00:29:42,779
it had an unbelievable growth spurt,
568
00:29:42,781 --> 00:29:44,914
basically going from being a toddler
569
00:29:44,916 --> 00:29:48,584
to a teenager in the single tick of a clock.
570
00:29:48,586 --> 00:29:53,056
How could the universe get so big so quickly?
571
00:29:53,058 --> 00:29:55,058
If we believe the big bang story,
572
00:29:55,060 --> 00:29:56,392
it appears to have broken
573
00:29:56,394 --> 00:30:01,397
one of the most fundamental laws of physics.
574
00:30:01,399 --> 00:30:05,535
Did the early universe really grow faster
575
00:30:05,537 --> 00:30:07,137
than the speed of light?
576
00:30:26,958 --> 00:30:28,958
In the classic big bang story,
577
00:30:28,960 --> 00:30:30,827
the observable universe expands
578
00:30:30,829 --> 00:30:34,764
from a ball of energy smaller than an atom.
579
00:30:34,766 --> 00:30:36,634
Today, the universe is estimated
580
00:30:36,636 --> 00:30:41,971
to be 93 billion light years in diameter.
581
00:30:41,973 --> 00:30:45,108
Think about the vast universe that we see all around us today,
582
00:30:45,110 --> 00:30:47,444
and it was once a tiny, tiny little volume,
583
00:30:47,446 --> 00:30:49,112
unimaginably dense.
584
00:30:49,114 --> 00:30:51,714
The universe must've gone through a colossal growth spurt.
585
00:30:55,655 --> 00:30:57,387
With a steady rate of expansion,
586
00:30:57,389 --> 00:30:59,923
there simply hasn't been enough time for the universe
587
00:30:59,925 --> 00:31:04,794
to grow to its current size.
588
00:31:04,796 --> 00:31:08,598
Regions of the universe that were close neighbors in the past
589
00:31:08,600 --> 00:31:11,600
are now so far apart that their separation can't be
590
00:31:11,602 --> 00:31:16,873
explained by normal expansion.
591
00:31:16,875 --> 00:31:19,876
And the huge size of the cosmos
592
00:31:19,878 --> 00:31:22,879
is not the only strange thing we've discovered.
593
00:31:22,881 --> 00:31:27,684
The universe is what astronomers call flat.
594
00:31:27,686 --> 00:31:32,756
Sutter: Our universe is lumpy and bumpy at small scales.
595
00:31:32,758 --> 00:31:35,225
There's galaxies. There's black holes.
596
00:31:35,227 --> 00:31:36,759
There's people.
597
00:31:36,761 --> 00:31:40,230
There's all sorts of junk, but at large scales,
598
00:31:40,232 --> 00:31:41,564
global scales,
599
00:31:41,566 --> 00:31:46,369
truly universal scales, our universe is flat.
600
00:31:49,574 --> 00:31:52,009
Could this universal flatness
601
00:31:52,011 --> 00:31:54,710
and the super rapid growth
602
00:31:54,712 --> 00:31:56,312
somehow be connected?
603
00:32:00,585 --> 00:32:03,853
we know that the big bang wasn't an explosion,
604
00:32:03,855 --> 00:32:07,724
or matter in the universe would be unevenly distributed.
605
00:32:09,794 --> 00:32:12,194
yet something pushed everything
606
00:32:12,196 --> 00:32:15,932
outwards and fast, but what?
607
00:32:18,736 --> 00:32:22,805
in 1980, Alan guth, a young Stanford cosmologist,
608
00:32:22,807 --> 00:32:26,409
came up with a potential answer.
609
00:32:26,411 --> 00:32:30,146
His theory of inflation says the observable universe
610
00:32:30,148 --> 00:32:33,149
expanded from being smaller than an atom
611
00:32:33,151 --> 00:32:38,487
to the size of a basketball almost instantaneously.
612
00:32:38,489 --> 00:32:40,356
In this tiny fraction of a second
613
00:32:40,358 --> 00:32:41,957
at the beginning of the universe,
614
00:32:41,959 --> 00:32:45,262
like a millionth of a second but a millionth of that,
615
00:32:45,264 --> 00:32:47,297
a millionth of that and a millionth of that,
616
00:32:47,299 --> 00:32:49,298
the universe expanded by ...
617
00:32:49,300 --> 00:32:51,234
take the size of the universe at that time
618
00:32:51,236 --> 00:32:55,505
and multiply it by a one with, say, roughly 50 zeros behind it.
619
00:32:55,507 --> 00:33:00,977
Inflation drove the accelerated expansion of the universe,
620
00:33:00,979 --> 00:33:04,714
made it get really, really big really, really fast,
621
00:33:04,716 --> 00:33:07,716
and then it stopped.
622
00:33:07,718 --> 00:33:09,185
Inflation seems to solve
623
00:33:09,187 --> 00:33:11,988
two big bang headaches ...
624
00:33:11,990 --> 00:33:14,924
how the universe got so huge so quickly
625
00:33:14,926 --> 00:33:19,262
and why it's so flat.
626
00:33:19,264 --> 00:33:22,198
Because it inflated everywhere at once,
627
00:33:22,200 --> 00:33:26,135
all the energy in the universe which would turn into matter
628
00:33:26,137 --> 00:33:32,075
was pushed out evenly at the same time and same pace.
629
00:33:32,077 --> 00:33:34,009
Sutter: And the first stars grow together
630
00:33:34,011 --> 00:33:35,678
to become the first galaxies.
631
00:33:35,680 --> 00:33:40,683
Even here, us, in the solar system, we're born.
632
00:33:40,685 --> 00:33:45,555
We're seeded in the event of inflation.
633
00:33:48,026 --> 00:33:50,226
Parts of the universe that are now separated
634
00:33:50,228 --> 00:33:52,830
by 93 billion light years
635
00:33:52,832 --> 00:33:57,433
once had the same cosmic zip code.
636
00:33:57,435 --> 00:34:01,704
To have expanded so quickly, inflation must have broken
637
00:34:01,706 --> 00:34:05,174
one of the fundamental rules of physics.
638
00:34:05,176 --> 00:34:07,376
We all know that one rule the universe sticks to
639
00:34:07,378 --> 00:34:09,646
all the time is that nothing can travel
640
00:34:09,648 --> 00:34:11,581
faster than the speed of light.
641
00:34:11,583 --> 00:34:14,384
So how can we possibly say that the universe expanded
642
00:34:14,386 --> 00:34:16,986
faster than the speed of light?
643
00:34:16,988 --> 00:34:18,988
But inflation says the universe
644
00:34:18,990 --> 00:34:21,991
expands into nothingness.
645
00:34:21,993 --> 00:34:24,927
There was no outside of the universe.
646
00:34:24,929 --> 00:34:27,931
The universe was everything.
647
00:34:27,933 --> 00:34:31,601
So space itself was inflating,
648
00:34:31,603 --> 00:34:35,605
and space can move as fast as it wants.
649
00:34:35,607 --> 00:34:37,340
You can't go faster than the speed of light
650
00:34:37,342 --> 00:34:38,808
through space,
651
00:34:38,810 --> 00:34:41,144
but space itself is allowed to stretch and expand
652
00:34:41,146 --> 00:34:42,812
as fast as it wants,
653
00:34:42,814 --> 00:34:45,414
and that's what our universe is doing.
654
00:34:45,416 --> 00:34:47,817
The idea of inflation smooths out the universe
655
00:34:47,819 --> 00:34:49,352
in kind of a peculiar way.
656
00:34:49,354 --> 00:34:51,821
You can kind of think of it as having a sheet
657
00:34:51,823 --> 00:34:53,356
with a lot of wrinkles in it,
658
00:34:53,358 --> 00:34:55,892
and if you take that sheet and snap it really hard,
659
00:34:55,894 --> 00:34:58,227
those wrinkles very suddenly flatten out.
660
00:34:58,229 --> 00:35:04,033
The theory of inflation is one of the craziest-sounding ideas
661
00:35:04,035 --> 00:35:06,035
in the history of science,
662
00:35:06,037 --> 00:35:09,706
so crazy that it might just be right.
663
00:35:09,708 --> 00:35:12,842
Inflation helps us to understand the inexplicable,
664
00:35:12,844 --> 00:35:14,977
but there's a problem.
665
00:35:14,979 --> 00:35:19,983
We don't know what triggered or powered inflation.
666
00:35:19,985 --> 00:35:22,785
The inflationary universe idea imagines
667
00:35:22,787 --> 00:35:24,320
that the universe was suffused
668
00:35:24,322 --> 00:35:27,991
with some kind of ultradense energy at early times,
669
00:35:27,993 --> 00:35:30,593
something that pushed the universe apart.
670
00:35:30,595 --> 00:35:35,998
What caused there to be that hot expanding stuff?
671
00:35:36,000 --> 00:35:37,333
We have to be humble and acknowledge
672
00:35:37,335 --> 00:35:40,069
that we don't know for sure.
673
00:35:40,071 --> 00:35:41,871
But whatever started it,
674
00:35:41,873 --> 00:35:45,341
inflation was over in a split second.
675
00:35:45,343 --> 00:35:47,143
Sutter: It didn't last very long,
676
00:35:47,145 --> 00:35:50,480
and this is difficult to understand.
677
00:35:50,482 --> 00:35:55,017
How did inflation stop?
678
00:35:55,019 --> 00:35:58,154
We don't know. We got nothing, folks.
679
00:35:58,156 --> 00:36:01,356
Well, we got some things, but it's tough.
680
00:36:01,358 --> 00:36:04,493
It's tough.
681
00:36:04,495 --> 00:36:09,766
But has the process of inflation really stopped?
682
00:36:09,768 --> 00:36:14,170
One radical theory proposes if the force called inflation
683
00:36:14,172 --> 00:36:17,840
kick-started the expansion of one universe,
684
00:36:17,842 --> 00:36:21,310
then why not another and another and another?
685
00:36:23,848 --> 00:36:29,118
is inflation creating a whole series of new universes?
686
00:36:29,120 --> 00:36:32,955
Is there a multiverse?
687
00:36:45,203 --> 00:36:48,470
If we believe the big bang story,
688
00:36:48,472 --> 00:36:53,142
a dot smaller than an atom expanded to make a universe
689
00:36:53,144 --> 00:36:56,145
93 billion light years across.
690
00:36:56,147 --> 00:36:58,681
A theory called cosmic inflation
691
00:36:58,683 --> 00:37:01,751
claims to explain this stupendous growth.
692
00:37:07,959 --> 00:37:11,828
but inflation may create more questions than answers.
693
00:37:13,965 --> 00:37:16,566
inflation gave us more than we had bargained for.
694
00:37:16,568 --> 00:37:18,167
We tried to come up with a mechanism
695
00:37:18,169 --> 00:37:21,370
that would just create our universe and stop
696
00:37:21,372 --> 00:37:22,571
and then quickly realized that,
697
00:37:22,573 --> 00:37:24,307
actually, just like most car factories
698
00:37:24,309 --> 00:37:25,908
don't produce one car and then stop
699
00:37:25,910 --> 00:37:29,712
but produce many cars, inflation tends to produce one universe
700
00:37:29,714 --> 00:37:34,650
then another and a vast number of them, a multiverse.
701
00:37:34,652 --> 00:37:38,187
It's a process called eternal inflation.
702
00:37:38,189 --> 00:37:42,458
It proposes that while inflation ended in our universe
703
00:37:42,460 --> 00:37:45,127
and led to formation of stars and galaxies,
704
00:37:45,129 --> 00:37:49,331
we're just one small part of a vast continuously
705
00:37:49,333 --> 00:37:52,067
inflating multiverse.
706
00:37:52,069 --> 00:37:56,339
Imagine a series of bubbles next to each other.
707
00:37:56,341 --> 00:37:58,141
Those are the different universes,
708
00:37:58,143 --> 00:38:00,743
and so our bubble is expanding,
709
00:38:00,745 --> 00:38:02,745
and we're bumping into our neighboring universe,
710
00:38:02,747 --> 00:38:05,348
and we're going to expand into it
711
00:38:05,350 --> 00:38:09,552
if the multiverse theory is correct.
712
00:38:09,554 --> 00:38:10,953
A big bubbling multiverse
713
00:38:10,955 --> 00:38:14,324
sounds like science fiction,
714
00:38:14,326 --> 00:38:18,694
but there is prospective evidence to back up the theory.
715
00:38:18,696 --> 00:38:21,497
Scientists have spotted an unusual Mark
716
00:38:21,499 --> 00:38:25,701
on the cosmic microwave background,
717
00:38:25,703 --> 00:38:30,106
that snapshot of the infant universe.
718
00:38:30,108 --> 00:38:33,442
There's a spot in the Southern hemisphere
719
00:38:33,444 --> 00:38:37,046
that's not necessarily the coldest spot
720
00:38:37,048 --> 00:38:38,647
or the biggest spot,
721
00:38:38,649 --> 00:38:42,050
but it's the coldest biggest spot,
722
00:38:42,052 --> 00:38:44,319
and it's strange.
723
00:38:44,321 --> 00:38:47,723
We don't know how to fully explain it.
724
00:38:47,725 --> 00:38:50,459
One unproven but intriguing theory
725
00:38:50,461 --> 00:38:54,530
is that this area is a kind of cosmic dent,
726
00:38:54,532 --> 00:38:59,402
surface dent from an impact with another universe.
727
00:38:59,404 --> 00:39:00,736
I work in the building with the people
728
00:39:00,738 --> 00:39:03,272
that discovered this giant cold area,
729
00:39:03,274 --> 00:39:04,673
and they were pointing it out and saying,
730
00:39:04,675 --> 00:39:06,208
"well, that doesn't make any sense.
731
00:39:06,210 --> 00:39:08,478
"Why would the microwave background be like that?
732
00:39:08,480 --> 00:39:10,813
"Hey, maybe that's evidence of another universe
733
00:39:10,815 --> 00:39:12,681
interacting with our own."
734
00:39:12,683 --> 00:39:14,217
That's something that, when you go to lunch,
735
00:39:14,219 --> 00:39:17,753
makes you pause.
736
00:39:17,755 --> 00:39:19,288
If you buy into the idea
737
00:39:19,290 --> 00:39:21,624
of a crowded multiverse,
738
00:39:21,626 --> 00:39:25,895
cosmic bangs and scrapes are not only perfectly possible,
739
00:39:25,897 --> 00:39:27,897
they're probable.
740
00:39:27,899 --> 00:39:30,566
There may be many universes outside expanding
741
00:39:30,568 --> 00:39:32,835
under the force of inflation right now.
742
00:39:32,837 --> 00:39:34,237
One analogy is
743
00:39:34,239 --> 00:39:36,572
think about a superhero that just can't be killed.
744
00:39:36,574 --> 00:39:39,909
They keep regenerating.
745
00:39:39,911 --> 00:39:42,845
If the multiverse narrative is correct,
746
00:39:42,847 --> 00:39:47,917
it places a giant question Mark over the story of the big bang.
747
00:39:47,919 --> 00:39:50,519
The possibility of a multiverse suggests
748
00:39:50,521 --> 00:39:54,123
not just one but a whole series of big bangs.
749
00:39:56,861 --> 00:40:01,730
but not all physicists buy into this thesis.
750
00:40:01,732 --> 00:40:04,667
The community is divided on the idea of the multiverse,
751
00:40:04,669 --> 00:40:08,204
predictably, because there are some of us who believe
752
00:40:08,206 --> 00:40:11,874
that this sort of leap of imagination is justified,
753
00:40:11,876 --> 00:40:13,943
and there are others, sort of hardliners,
754
00:40:13,945 --> 00:40:16,612
who think that, until we have empirical evidence,
755
00:40:16,614 --> 00:40:19,214
this is not a scientific idea.
756
00:40:19,216 --> 00:40:20,749
Others welcome the fact that,
757
00:40:20,751 --> 00:40:23,686
when it comes to explaining everything,
758
00:40:23,688 --> 00:40:28,824
we're not simply stuck with the good old big bang narrative.
759
00:40:28,826 --> 00:40:31,093
I would've felt kind of claustrophobic
760
00:40:31,095 --> 00:40:33,762
if it turned out that all that existed was earth,
761
00:40:33,764 --> 00:40:35,497
and I was happy that we discovered
762
00:40:35,499 --> 00:40:36,766
that it was part of something bigger,
763
00:40:36,768 --> 00:40:39,301
the solar system, the galaxy,
764
00:40:39,303 --> 00:40:40,969
a cluster of galaxies or universe,
765
00:40:40,971 --> 00:40:44,440
so I'd feel even better if there's still more space out
766
00:40:44,442 --> 00:40:47,576
there and parallel universes,
767
00:40:47,578 --> 00:40:50,379
the more the merrier.
768
00:40:50,381 --> 00:40:52,247
While it's an appealing notion,
769
00:40:52,249 --> 00:40:54,116
without empirical evidence,
770
00:40:54,118 --> 00:40:56,652
it's a theory requiring a leap of faith.
771
00:40:59,390 --> 00:41:02,258
there's no reason to think that the tiny, little creatures
772
00:41:02,260 --> 00:41:07,529
that we are actually perceive the vast true nature of reality.
773
00:41:07,531 --> 00:41:09,465
This is still an absolute puzzle.
774
00:41:09,467 --> 00:41:11,400
We have ideas. I have ideas.
775
00:41:11,402 --> 00:41:13,736
Other people have proposed models, right?
776
00:41:13,738 --> 00:41:15,805
But we have no data, really, that helps us
777
00:41:15,807 --> 00:41:18,140
distinguish between these ideas, and to be honest,
778
00:41:18,142 --> 00:41:22,211
the ideas themselves aren't fully fleshed out.
779
00:41:22,213 --> 00:41:24,280
Support for the classic big bang model
780
00:41:24,282 --> 00:41:27,483
seems to be increasingly shaky.
781
00:41:27,485 --> 00:41:29,952
The latest thinking proposes not one,
782
00:41:29,954 --> 00:41:31,554
but a whole series of big bangs.
783
00:41:35,626 --> 00:41:39,362
as scientists continue to rewrite the traditional story,
784
00:41:39,364 --> 00:41:42,498
more and more questions are being asked,
785
00:41:42,500 --> 00:41:47,102
but for now, many remain unanswered.
786
00:41:47,104 --> 00:41:48,704
What was the origin?
787
00:41:48,706 --> 00:41:53,575
Is there even a sense to asking, "was there a time before time?"
788
00:41:53,577 --> 00:41:55,110
And I think the answer is yes.
789
00:41:55,112 --> 00:41:58,047
You know, our science and our math, they're just incomplete.
790
00:41:58,049 --> 00:41:59,982
Some day, we may have the mathematics
791
00:41:59,984 --> 00:42:02,718
to describe the earliest moments of the universe.
792
00:42:02,720 --> 00:42:05,220
Some day, we may be able to make predictions
793
00:42:05,222 --> 00:42:07,389
that we can connect to observations.
794
00:42:07,391 --> 00:42:09,525
Just because that day isn't today
795
00:42:09,527 --> 00:42:11,961
doesn't mean that that day will never come.
796
00:42:11,963 --> 00:42:14,597
We've learned an enormous amount in the last 100 years,
797
00:42:14,599 --> 00:42:17,333
but now we're left with some pretty serious puzzles
798
00:42:17,335 --> 00:42:20,803
that are gonna be really tough to solve,
799
00:42:20,805 --> 00:42:22,738
so I'm waiting for the next Einstein.
62513
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