O Que é o Nada? (3ª Temporada - Através do Buraco de Minhoca)

Freeman: Nothingness.
It is the beginning
and the end of all creation.
But what is it?
Is empty space really empty?
Or is it filled with hidden forces...
...forces that exploded our Universe into existence...
...or forces that could destroy reality as we know it?
What is nothing?
Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
♪ Through the Wormhole 03x05 ♪ What is Nothing? Original Air Date on June 27, 2012
== sync, corrected by elderman ==
The void.
The Bible says it was the place
from which God brought forth the heavens and the earth.
Scientists now have their own version of that belief.
They call it the Big Bang.
But how can something come from what appears to be nothing?
Understanding the true nature of nothingness
is perhaps the deepest and most-baffling conundrum
in modern science.
It could explain where the Universe came from
and whether everything we know and love
could turn into nothing once again.
"In the beginning, the earth was without form."
When you were young,
did you ever close your eyes
and try to imagine floating in total darkness,
to experience absolute nothing?
I did.
And I always failed.
No matter what,
I could not rid this void of the pulse of my heartbeat
and the thoughts in my head.
When I imagine,
I can't help but imagine something,
not nothing.
Slava Turyshev is a NASA physicist
who has always dreamed of nothing
and what nothing might be like to visit.
Turyshev: The town I was born in
was just under the trajectory rockets launched from Baikonur.
It's a Russian launch site.
So that actually made a major impression on me.
Freeman: Slava spent his childhood building rockets
and yearned to one day ride one
into the emptiness of outer space.
But fate had other plans.
Turyshev: I wanted to be on a space flight,
and at one of those times actually was training
for the Russian space shuttle back in late '90s,
just before the program was canceled.
Freeman: With no Russian shuttle,
Slava lost his ticket to outer space,
but as a physicist,
he discovered that the same space that fills the heavens
also exists everywhere on earth.
It's just not empty down here.
And exploring the fundamental properties of space
does not require a billion-dollar rocket.
In fact, all you need is a bucket of water.
This is actually a very simple experiment.
What I'll do, I'll put some water in the bucket,
and this experiment actually was thought by Isaac Newton.
The objective, of course,
to see what's going on with the water when we spin the bucket.
So, let's spin it very, very nice.
So, stable.
You can observe that the water in the bucket is staying flat.
And let's see what happens.
Freeman: Isaac Newton thought that the water
ought to spin in lockstep with the bucket,
just as we move with the spinning earth.
But the water does not move
with the spinning bucket at first.
Eventually, friction from the inner wall of the bucket
drags the water upwards.
Turyshev: So, you can see
that the water is slowly going upwards in the bucket.
Freeman: But in the first moments after the bucket is set in motion,
the water stays still.
Newton realized there must be something gluing the water
to the larger world around it.
He thought that glue must be space itself,
which exists all around and inside the bucket.
Indeed, we cannot assume that space is nothing.
There is something,
and that something influences how matter moves.
Freeman: Newton could not explain
how the nothingness of space was somehow something.
But in 1915, Albert Einstein's
revolutionary Theory of General Relativity
showed that Newton's idea was fundamentally right.
Space or, as he reformulated it, Space-Time
is a bendable fabric
into of which all the matter in the Universe is woven.
The space that fills every corner of our Universe
plays a constant game of tug of war with all the things in it,
be they planets, water in a bucket, or a stack of papers.
So if empty space is not nothing,
then what is it?
Frank Close is a particle physicist.
He's learned that the power of empty space
should never be underestimated.
Hi, Andrew. Hi, Frank.
So, it's a metal drum,
and you can make it collapse by doing nothing.
That's rig.
We're gonna use the power of nothing.
So, this is pretty dramatic.
I better put this on, right?
Guess we had, yeah.
Uh-huh. And what else do I do?
So, if you just switch on the pump for me.
Okay.
[ Machine whirs ]
[ Metal bangs ]
Whew!
[ Exhales deeply ]
Wow.
The power of nothing.
We took all of the air out of the inside of this drum.
The atmosphere on the outside
was making a 10-tons-every-square-meter force
on that drum -- far too strong for the metal to resist.
Collapse.
So, nothing on the inside.
10 or 20 tons on the outside.
Bingo!
[ Metal bangs ]
Freeman: In his quest to understand
the fundamental forces of nature,
Frank has discovered that empty space can do far more
than cause solid matter to implode.
He thinks it is interfering with everything matter does.
Close: In the 19th century,
they thought if you take all the air out,
what you're left with is a genuinely empty vacuum.
And that is how it could have stayed
except that we then discovered the idea of Quantum Theory.
And one of the great mysteries underlying Quantum Theory
is that at an instant in time,
you cannot be absolutely sure how much energy there is.
Energy can be borrowed or exchanged around
on very short time scales.
So, in modern Quantum Theory,
the vacuum is a very violent place,
even though you and I,
day-to-day, aren't aware of that fact.
Freeman: Empty space is a froth of bubbling energy,
like molten metal.
And Frank and his fellow particle physicists
now have proof that this energy
shields us from seeing the true strength
of the fundamental forces of the Universe --
forces like the electrical repulsion
between charged particles.
So, we imagine an electron sitting here,
spreading out its electrical tentacles through space,
and I got another electron here that I will use
and I'll measure the force between them,
and the closer it gets,
the force will rise more and more.
But we now know, because of the Quantum Theory,
is that that little electron sitting there
is actually not isolated.
It is surrounded by the quantum vacuum.
So, it's an electron in a shroud.
And that shroud reduces the full impact of its electrical force.
The same thing is true of this other electron.
Freeman: Frank believes
that all historical measurements of the electrical force
are inaccurate because of these energy shrouds.
But now atom smashers,
like the Large Hadron Collider in Geneva, Switzerland,
can tell the full story.
Here, subatomic particles collide
at more than 670 million miles per hour.
They get so close to one another
that they finally pierce the shroud.
But eventually the clouds get inside each other,
and that's when it gets interesting,
and the clouds then are so disbursed around,
we at last see the bare electron
acting on the other bare electron.
And that's when we discover that the force
is much more dramatic than we'd thought before.
Freeman: Just like protective eyewear
that shields a welder from dangerously intense light,
Frank believes that empty space itself
is insulating the Universe
from the true intensity of the forces of nature.
If it was possible to turn off that cloak around the electron,
you'd have turned off all of the effects of the vacuum,
and you would actually, at the same time,
have destroyed the Universe.
Because all structure --
the existence of atoms and molecules --
could not be if it wasn't for the Quantum Theory.
Freeman: Without the dampening energy buzzing around in the vacuum,
the fundamental forces of nature would run out of control.
Our entire Universe would break apart.
But that is only one side of the story.
Because locked inside this dampening shroud,
there should be enough energy to trigger an explosion
deadlier than anything we have ever known.
Empty space might be a powder keg waiting to explode.
It might surprise you to know that our best theory
of how the Universe works down at the microscopic level --
the Theory of Quantum Mechanics --
also predicts empty space has enough energy
to boil the Universe out of existence.
But it doesn't.
Something must be keeping nothing in check.
Question is...
what?
Neal Weiner is a theoretical physicist
at New York University.
He studies the showers of subatomic particles
produced by atom smashers like the LHC in Geneva
and the Tevatron in Chicago.
Weiner: So, suppose that you take these two rocks
and you think of them as protons.
You collide them together from opposite directions,
and when you do that,
you have enough energy in the collision
that you can actually make particles
that you would never think of
as being part of the individual protons.
My job is to try to make sense of what they find
when they've collided these particles together.
Freeman: But to understand the shrapnel
flying out of these subatomic explosions,
Neal must look at the Universe in a way that seems strange.
He must see the smallest building blocks of solid matter
as not solid at all.
Weiner: In the Quantum realm, if you create particles,
you're creating them in a state that looks more like a wave
than it does like a particle.
Just like we have in a fountain,
where you have water coming down
and sourcing waves that then spread out from a central point,
in Quantum Mechanics, when you source a particle,
you have a wave that spreads out from a central point,
rather than a particular particle
going in any given direction.
Freeman: Just like the ripples on the surface of a pond,
a particle wave will spread itself
over the entire ocean of space,
and that means that at every point in the Universe,
there exists ripples
from trillions upon trillions of particle waves.
There is no such thing as empty space.
And the energy contained in that great rippling ocean
is causing the Universe to expand.
When you look at the expansion of the Universe,
you see galaxies, galaxy clusters, all expanding away --
everything flying away from each other.
And it turns out that the Universe is not slowing down.
The Universe is actually speeding up its expansion.
The Universe is accelerating.
So the only way that we know how to explain this
is if there's something like an energy density
that is pervasive in Space itself.
If you have that,
that's going to cause the Universe to accelerate.
Freeman: Physicists call this "dark energy."
From the rate of expansion of the Universe,
they can measure how much of it empty space contains.
But when they tallied that number
against how much energy empty space ought to have
from all the particle waves filling the Universe,
there was a staggering mismatch.
When you calculate the amount of energy
that there should be in empty space from quantum effects,
you get a number which is 10 to the 120 times larger
than the number that we actually observe
from the expansion and the acceleration of the Universe.
And this is an enormous number.
Freeman: According to their calculations,
there should be enough energy in space itself
to boil the Universe away.
But we are still here.
Neal and many of his colleagues think they might know
why such a big mismatch exists between theory and observation.
It could be that most particle waves
are canceling each other out.
Weiner: The cancelation of waves
is a pretty easy phenomenon to understand.
You just simply imagine you have one wave,
which has peaks and troughs,
and then you have another wave that has peaks and troughs,
and when those waves combine,
if the peaks and troughs are in the same place --
if I have two peaks in the same place -- they add together.
If I have two troughs in the same place,
they add together negatively.
But if I have one peak and one trough,
they cancel out, and I'm left with nothing.
And so this interference,
this phenomenon of how waves can cancel,
carries over to particles.
Freeman: Neal thinks there is a whole other set
of as-yet-undetected particles out in the Universe,
each creating waves,
which cancel out the waves from the particles we know.
It's an idea known as supersymmetry --
every particle has a mirror-image partner.
The fact that my Universe allows electrons
means that I should have the possibility of creating selectrons.
And if I have quarks, I should have squarks.
Freeman: And Neal's supersymmetric partner should be...
Sneal.
If you're in New York, you're either a lawyer,
you're in finance, or you're an actor, and I can't act.
Freeman: But finding Sneal
or any other supersymmetric particle wave
is a frustrating task.
Weiner: You can look for them directly.
You can look for them indirectly.
I have all sorts of ways to look for supersymmetry.
But up to this point,
it's done an excellent job of hiding from us,
so either we're about to find it
or I think a lot of us are gonna say it's just not there.
Freeman: The LHC has so far seen no sign of supersymmetric particles.
If they do not exist,
scientists will be left with a baffling predicament --
explaining why the energy of empty space
is not tearing our Universe to shreds.
But other scientists believe
a cataclysmic explosion of nothing is inevitable.
And one has worked out
when it might happen.
And one has worked out
Empty space fills our cosmos
like a great ocean of nothingness.
But the still waters of the Universe
may not be tranquil for long.
As one scientist sees it,
a storm may be brewing.
Max Tegmark is a cosmologist at M.I.T.
Do not let his relaxed charm fool you.
He is deeply troubled.
What is on his mind
is nothing other than the future of empty space.
Space itself seems just imminently stable and permanent,
just like these golf balls here.
Been hitting these around for quite a while now,
and they always look the same afterwards,
but how can I be really, really sure that stuff is stable?
Just like the golf ball changed its state into a cloud of dust,
could space itself somehow change its state
into something else?
Freeman: A rapid decay of space into a different state
may sound highly unlikely,
but it is not without precedent.
13.7 billion years ago,
the Universe shifted its fundamental properties
and its temperature plummeted.
Physicists call this the Big Bang.
And through Max's eyes,
there was something fishy about it.
[ Laughs ]
I pretend I'm a fish.
I've spent my whole life in the ocean,
and I think of water as just empty space,
'cause that's all I know.
And then one day,
I realize that this emptiness is actually a substance.
And I am an interested and curious fish,
so I figure out in addition to the liquid water, which I'm in,
there is this solid phase -- ice -- and there's steam.
And then I would start worrying about whether one day, you know,
my water might freeze and I might die.
And in exactly the same way we've looked at our space,
realized that it, too, seems to be able to freeze
and kill us all.
Freeman: Max thinks the Big Bang
was not the last cosmic freeze our Universe will experience,
and his proof lies in the mind-bending science
of Quantum Mechanics,
where nothing is fixed and nothing can last forever.
Quantum Mechanics tells you that a particle
can never be perfectly still
in a known position.
And Quantum Mechanics tells you that
not just about little things like atoms,
but also about big things that are made of atoms,
like this golf ball.
Which means nothing is completely stable.
This quantum jiggling of things will eventually,
if I were to stand here long enough,
cause the golf ball to just randomly go up a little bit,
then fall down into a lower energy state.
Freeman: Left alone on the tee, there was a very slight chance
this golf ball will tunnel through space
and materialize closer to the ground,
where its energy is lower.
When an object tunnels through space,
it can end up practically anywhere,
as long as its energy is lower.
It could even tunnel into the tin cup --
a perfect hole-in-one without even swinging.
But this phenomenon could be bad news for the Universe.
We physicists have found pretty good evidence that space itself
can be in several different energy states --
lower, medium, higher.
And we also have good reason to believe
that our space used to be in a much higher energy state
in the early Universe,
in which even the kinds of particles that could exist
were different.
Now, this early Universe, which gave us our Big Bang,
was unstable and very quickly decayed
into a lower energy state that we inhabit today,
with this peaceful, very nice, and inhabitable Space
which contains our kinds of particles that we're made of.
But we've also measured
that there must be an even lower state,
because our empty space, as we call it, isn't empty.
It has mass, and as such,
should be able to decay...
into an even lower energy state,
where our kinds of particles aren't allowed to exist.
And since I'm made out of that kind of particles,
that would be a bit of a bummer for me.
Freeman: When this sudden decay in the energy of empty space happens,
a blast of destructive nothingness
will spread through the Universe at the speed of light.
We will have no way to see it coming.
It's inevitable.
What's very unclear, though, is how long it's gonna last.
Some things are a lot more stable than others, you know?
A uranium atom will last for billions and billions of years,
whereas, say, a Cesium-137 atom
that leaked out of a nuclear reactor
is gonna fall apart much quicker,
making it more dangerous.
And then this Universe we're in --
you know, we've been here for almost 14 billion years,
but that doesn't mean it's gonna be around forever.
Freeman: On the conservative side,
Max thinks we could have 20 billion years left,
but that depends on supersymmetry particles
actually existing --
the same particles Neal Weiner is hoping to see
and the LHC has so far failed to find.
Without supersymmetry to stabilize empty space,
it could all end in just one billion years --
the blink of a cosmic eye.
I'm just laughing because...
...at the end of "Life of Brian,"
one of my favorite Monty Python movies, they say,
[British accent] "We come from nothing. We go back to nothing.
What have we lost? Nothing!"
[ Laughs ]
Nothing could be the beginning and the end of the Universe,
but there's another way of looking at nothing.
The Universe could be a giant bubble.
Everything that is...something
fits on the surface.
And the inside is just a waste of space.
When we look at the twinkling starlight in the night sky,
it's hard to understand the vast distances
that separate us from those stars --
the trillions upon trillions of miles of emptiness.
But that's not the way the ancients saw it.
To them, the stars were just points of light
on a black shell that surrounded the Earth.
Outer space did not exist.
Now some bold thinkers
are embracing this period of this idea again --
a thousand years after the idea was abandoned.
Gerard 't Hooft won the Nobel Prize in Physics in 1999
for his work in establishing the standard model --
the basic foundation of particle physics today.
You could call him one of the kings of modern physics.
But you could also call him high lord of nothing.
Well, almost nothing.
Because this barren rock is his own private asteroid
floating 100 million miles from Earth.
The international astronomical union
had decided to name the asteroid "9491 't Hooft."
I was, of course, very flattered and honored by the event,
but one little thing struck me,
and it was that they changed the spelling of my last name.
It now became "Thooft," with a capital "T"
and then "hooft" just spelled right after it,
without apostrophe.
Freeman: Gerard planned revenge --
a poetic revenge.
I decided that the asteroid would require a constitution,
and one of the first items in the constitution
is that all future inhabitants of this asteroid
would have to live without apostrophes.
Anyone entering the territorial zone of the asteroid
with a laptop, for instance,
that carries a key with an apostrophe in it,
that key of the laptop would have to be removed.
Freeman: As King of his asteroid,
Gerard is free to ban apostrophes.
But as a Nobel laureate, he knows they still exist.
In fact, Gerard believes that anything that is something
can never truly be removed from the Universe.
It's a principle called the conservation of information.
You might think
that the information people put in documents
is completely lost once it's like this,
but actually that's not true.
I could dig it up and I can try to put all the pieces together.
The information is still in it.
Freeman: Physicists like Gerard believe anything in the Universe
can be described by a series of bits,
or ones and zeros,
whether it is a piece of paper, a planet, or a star.
But there is one place in the cosmos
where this theory seems to fall apart --
black holes --
rapacious voids that pull in everything that gets too close.
't Hooft: The black hole is much better
than any of these shredders here.
In a black hole,
the information is not only shredded,
it completely disappears.
Freeman: In the 1970s,
legendary cosmologist Stephen Hawking
argued that black holes entirely remove objects
from our visible Universe,
and the information they swallow is gone forever.
It was a notion that deeply troubled Gerard.
't Hooft: And I said,
"that doesn't fit with the view we have about physics."
From the point of view of what we know about the atoms
and what's inside an atom, information doesn't go away.
It can't.
It would be against the laws of physics that we know.
Freeman: Hawking stood his ground,
and the two debated for years,
until a brilliant insight turned the tide.
Gerard realized that if 9491 Thooft
ever fell into a black hole,
it would not disappear without a trace.
It would ever so slightly change the black hole.
't Hooft: The black hole would go into a different state,
so the black hole would not be the same black hole
as it was before it ate my asteroid.
It would be a different black hole.
Freeman: When a black hole feeds on its prey, it grows,
and so its surface area gets slightly larger.
And when Gerard calculated exactly how much
extra information could fit onto this larger surface,
he discovered it was just enough to fit
all the information contained in the black hole's dinner.
The amount of information you could put in a black hole
is very precisely fine
and is proportional to its surface area.
It's not what's inside the surface.
It simply doesn't count.
It's the surface area that counts, not the volume.
Freeman: This means that the entire information content
of Gerard's doomed asteroid
and everything else devoured by the black hole
is imprinted across its surface area.
And Gerard discovered that this principle
applies to more than just black holes.
In fact, the information contained
inside any three-dimensional volume of space
must fit onto that volume's surface area.
You see that the box is covered by a grid,
and the amount of information no longer can be counted
while looking at the volume of the box,
but by looking at the surface of the box.
On every side of this grid, there's one bit of information.
Freeman: Think of a box the size of the entire Universe.
All of the information contained inside
fits neatly on a grid on the surface.
The total information content of everything that ever was
can be counted there.
Compared with how much space for information
exists inside the box,
it is practically nothing at all.
In principle, yes, you can --
it should be possible
to describe everything happening in the Universe
by concentrating on a surface surrounding it.
Freeman: If he is correct -- and most physicists now think he is --
the Universe is mostly a waste of space.
Because where there is no information,
there is really...nothing.
But this woman has taken the concept of nothing
one step further.
In fact, she may have found another Universe inside our own,
made of absolutely nothing.
If I close my eyes and nothing makes a sound,
how can I be sure the world is really there?
Or...if you can't see or hear me, how --
how do you know I really exist?
The difference between something and nothing
could be a matter of perception.
Katie Freese is an astrophysicist
with a competitive spirit.
I think this stems from my childhood,
because we lived on the corner of two blocks,
and all the kids came over to my house
to play baseball and basketball or whatever,
except it was all boys,
so I was always playing with the boys.
And as a physicist, I'm still doing that.
And [laughs] so I think that's where I developed
this sense of competition and thinking that it's fun.
Freeman: When she's not on the courts,
Katie peers into the heart of matter
and tries to understand what makes it solid.
When we look at the world around us, it seems to be really solid.
It looks solid, it feels solid, but it's not.
This tennis ball feels solid,
but when I cut it open...
...it's empty --
just like most of matter.
So, if we think about one grain of the sugar
that's on my fingertip,
and if that were equivalent to the nucleus,
then it would take this entire big tennis court
to make up the atom,
and in between the sugar,
the single grain that makes the nucleus
and this entire tennis court,
there's absolutely nothing.
It's empty.
Freeman: The solid world around us is merely an illusion.
What makes things feel solid
is nothing more than the repulsion of electrons
that exist on the outer shells of atoms.
And if you did not feel this force,
you could pass right through solid matter.
In the past two decades,
astronomers have discovered light
bending around gargantuan invisible masses
surrounding every galaxy.
They believe these masses are made of dark matter.
They call it dark
because we cannot see it, feel it, or touch it.
It passes right through our solid world
as if it was not there at all.
As far as dark matter goes,
we know that it does not have electric charge.
We would know.
I mean, these things would be bombarding you, and you'd know.
There are probably billions of dark-matter particles
passing through our bodies every second.
Freeman: Katie believes that dark matter
is made up of particles just as heavy as regular matter,
but they are only affected
by what scientists call the weak force --
a force so puny, its effect is barely detectable
by our most sophisticated equipment.
In my right hand, I have a tennis racket,
and in my left hand, I have a glass of sugar,
and we're gonna use these as props
to explain weak interactions.
The strings are representing regular matter
with a lot of space in between them,
so when the grains of sugar go through,
most of them just pass right on by
without having any interaction whatsoever.
Freeman: Katie believes that in one day,
of the few billion particles of dark matter
that pass through your body,
only two or three of them
will ever interact with the atoms inside you.
And when they do,
it is only through the weak force.
Highly sensitive experiments around the world
have been trying to detect these rare interactions
for over a decade,
but the experiments do not agree with one another.
Freese: One of the experiments has been seeing a signal for 10 years,
and it's a statistically very significant result.
But the problem is that some of the other experiments
are in disagreement because they're not seeing anything.
The question is, what's going on?
Freeman: As a scientist competing
in one of the biggest theoretical games in physics,
Katie is beginning to worry about an emerging possibility.
Dark matter may not even feel the weak force.
Freese: What a horrible thought.
Nobody said the dark matter had to weakly interact,
so then we really have a problem.
Then I don't know how we're ever gonna detect it.
How can we discover it?
That would be really discouraging.
[ Chuckles ] So let's hope not.
Freeman: If this is the case,
our Universe is divided into two worlds --
one of matter and one of dark matter.
And they will always be nothing to each other.
Like a tennis game where the rackets have no strings.
The most important contribution to the mass in the Universe
could really basically be nothingness.
So nothingness would rule. [ Laughs ]
Freeman: But is there or was there
ever such a thing as absolute nothing?
No energy, no matter, no time or space.
The answer to this question
might reveal the ultimate origin of our cosmos,
and this scientific pioneer thinks he has found it.
Only a decade ago,
astronomers confirmed what to many seemed utterly impossible.
Go back 13.7 billion years,
and there was only darkness.
Then our Universe exploded into existence.
How could everything come from nothing?
Gabriele Veneziano is the father of String Theory,
which has become one of the most important scientific ideas
in modern physics.
But his latest big idea challenges the mainstream.
He believes the Big Bang
could not have been the beginning of everything.
The conclusion that there was nothing --
I think it was too fast a conclusion,
so I don't want to repeat the same mistake.
Freeman: Gabriele believes that there was something
before the Big Bang.
But, like a city at daybreak,
most of this pre-Universe was fast asleep.
Veneziano: There were things propagating in space,
like waves, particles,
but the energy was very diluted,
and furthermore,
this wave or this particle interacted very, very weakly.
That would be like having very few people walking in the street
and, furthermore, not interacting with each other.
They may not talk to each other.
They may not feel each other.
Freeman: Gabriele believes
that the same fundamental forces of nature we know today
existed in the pre-Universe,
but their strengths were much lower.
Veneziano: The strength of all these forces
was given in terms of what we call a dilaton field.
Freeman: This dilaton field filled the entire pre-Universe
and controlled the strength of all the forces.
As it gradually dialed them all up,
things started to happen.
As time goes on, the density of people is increasing.
As a result,
the interactions are getting stronger and stronger.
So, you see people getting together, talking together,
making clusters of people together.
Freeman: The ever-growing pressure increases
and the interactions intensify until...
Things blow up.
Freeman: For Gabriele,
the Big Bang was not a sudden beginning,
but rather a tipping point.
If he is right,
he will have dispensed its most puzzling paradox --
getting something from nothing.
Proving there was never nothing in the Universe
may not be as difficult as you think.
Because if space and matter have always existed,
the Big Bang should have sent colossal gravitational waves
rippling through them,
and the aftershock of those waves
may still be detectable today.
If we could see gravitational waves,
we could go back much, much earlier,
ideally very, very close with the Big Bang.
Or if there was something before the Big Bang,
we can even go back to looking at the Universe
before the Big Bang.
Freeman: If gravitational waves left over from the pre-Universe exist,
they should be ever so slightly
stretching and squashing the spaces around us.
Engineers from around the world
are submitting designs for a new spacecraft
sensitive enough to detect these distortions.
Veneziano: The important thing is that there are experimental ways
to talk about these things.
I mean, they're not just pure science fiction.
I mean, you can put this model to a test.
Freeman: Gabriele's mission
to prove that nothing does not exist and never did
may be on the verge of success.
The ancient Greeks thought of nothing
as a logical impossibility.
The moment you think about nothing, it becomes something.
Modern scientists have spent centuries
thinking about nothing,
and what they've learned proved the greeks were right.
There may be enough energy
rippling through nothingness to destroy us,
entire Universes may be made of it,
And it is most definitely not nothing.
== sync, corrected by elderman ==