Through the Wormhole s08e01 Episode Script
Is The Force With Us?
Space A vast empty ocean where a planet like ours is a remote island Alone in the void.
Or is it? New research is beginning to unveil a hidden force, one that shakes the entire universe and penetrates space with trillions of invisible connections Instantly linking every place in our world and joining our future with our past.
Now we're beginning to grasp these mystical powers.
Is the force With us? Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
Captions by vitac captions paid for by discovery communications you know the story.
A long time ago in a galaxy far, far away, there was a mysterious force, surrounding us, penetrating us, binding the galaxy together.
If you could wield this force You could do astonishing things.
Seem like a Hollywood fantasy? Well, scientists now wonder whether something like the force could be real.
Could there actually be a mystical power that spans the universe, connecting and binding all things? Astrophysicist Jamie Rollins has spent his career listening to the universe, trying to detect a mysterious force one we've never been able to see.
Over the course of the history of astronomy, light has essentially been our only way of learning about the universe.
What we see out there is influenced by forces coming from things that we don't actually directly observe.
It's like walking around without being able to hear.
We know that there are sounds, and we know that we could learn a lot from them if we could hear them.
There is no sound in the vacuum of space.
But according to Albert Einstein, gravity affects space in a very similar way to sound.
We've been able to demonstrate many of the predictions of Einstein's general theory of gravity.
The one big one that we haven't is the fact that there should be waves of gravity.
Gravitational waves are one of Einstein's most elusive predictions.
He believed that space is not truly empty, but acts like a kind of substance that can be warped by masses like stars and galaxies.
And when massive objects move suddenly, they send ripples across space, squeezing and stretching everything they encounter from planets to the people living on them.
Detecting these gravitational waves would prove that we are physically joined to the cosmos by a fabric of space, and that events across the universe exert a tangible force on us.
But detecting this force is no easy task.
The waves that pass through the Earth are essentially unfathomably small.
We have to make incredibly sensitive detectors to be able to experience this effect.
LIGO the laser interferometer gravitational-wave observatory is one of the world's biggest scientific experiments.
Each of its arms is four full kilometers long.
To rule out Earthquakes and other forces, LIGO has two separate detectors one in Louisiana, one in Washington state.
LIGO compares the way two high-powered laser beams move up and down each of its long arms.
Mirrors at the end of each one bounce the laser beams back to the center, where they're compared by computers.
As long as the length of the two arms are exactly the same, then the light going into the two arms will come back and be exactly in synch.
If a gravitational wave passes through the Earth, it would cause the arms to squeeze and stretch, throwing the lasers out of phase with each other.
Jamie is one of LIGO's more than 1,000 scientists.
And, for him, the principle by which the detector works is very familiar.
As a former DJ, he's used to listening to tiny discrepancies in sounds.
Let's say I've got two identical records that I've started at the exact same time such that the songs are exactly synchronized together.
If we were to disturb one by, say, dragging my finger along the side, then this record would fall out of phase with the other one, which would produce a shift in the sound that we can hear.
If you're listening to one record, you might not notice that effect.
Now if we were to speed up on record and slow down the other, the songs come in and out of phase with each other.
This is very similar to what happens to the light in the arms of the interferometer.
The changes in length that we're looking for are so miniscule.
They're smaller than the nucleus of a single atom.
It's completely imperceptible to the normal physical world that we experience.
But in September 2015, after more than two decades of development and more than a billion dollars, LIGO finally detected a ripple in space.
It sensed a staggeringly violent event, one that took place a long time ago in a galaxy a billion light years away.
What we detected was a binary black hole system which is two black holes that are in a tight orbit around each other in fact, at the very end of their lifetime as a binary system.
As the two black holes spiraled together and collided, the fabric of space shuddered and a billion years later, LIGO felt it.
To Jamie, that ripple in space is proof that gravity connects everything in the universe.
It was incredibly gratifying.
But it's also the excitement to know that there's so much to be learned by having this new sensory perception in the universe.
It's really as if we're connected to the rest of the universe in a totally different way.
One omnipresent force, the force of gravity, binds the universe together.
But how does gravity actually connect planets, stars, and people? Cosmologist Claudia De Rham is taking aim at the elusive substance of gravity itself.
For all the forces that we know, there's a particle associated with that force, which is responsible for carrying the force through empty space.
When I bring that magnet close to the horseshoe, I can feel the magnetic force.
And for the magnetic force, the electric force, the particle is the photon.
It's not visible light, but it's there nonetheless.
And one of the great mysteries of physics today is whether there's a particle associated with the gravitational force.
Claudia is obsessed with finding gravity's hidden mechanism.
How does this mysterious force stretch across the cosmos, silently tugging on everything? But gravity is not easy to study.
Because of all the forces we know, gravity is the weakest.
We think of gravity as this huge, powerful force that keeps us glued to the surface of the Earth.
But, actually, it's remarkably easy to overcome.
All it takes is a few fans.
Right now, a powerful wind is pushing Claudia away from the Earth.
Molecules of air are hitting her body and forcing it upward.
But something else is forcing her down.
You could almost picture a tractor beam pulling me down.
And if anything is, in physics, we're having a huge debate on whether gravity is a force or not.
According to Einstein, there is no force of gravity pulling on these skydivers.
The huge mass of the Earth simply distorts the shape of space near it, and they follow the contours of that shape.
But quantum mechanics has a different approach.
According to this theory of the most fundamental particles, something really is passing between the skydivers and the Earth identical little chunks of gravity called gravitons.
Right now, I'm exchanging gravitons with the Earth.
They are traveling between the Earth and me.
If we could see gravitons, we'd see tractor beams everywhere, making hidden connections between everything that has mass.
Claudia believes these graviton tractor beams keep us all stuck to the Earth at least, when we're not in a wind tunnel.
But they have never been detected in any scientific experiment.
It's extremely hard to catch a graviton.
When a graviton comes, it just goes straight through me.
To detect the particles which carry forces, we build particle accelerators.
But if those forces are weak, we must build enormous particle accelerators, and gravity is trillions of times weaker than electromagnetism.
You could think of needing to have a detector of the massive Jupiter parked in orbit around a neutron star to have enough mass there to have maybe the chance of detecting one or two gravitons every century, and that's being very optimistic.
But if we could find the graviton and learn to manipulate it, we'd have in our hands a seemingly supernatural force.
Just as we focused photons into laser beams, we could focus gravitons into beams of gravity.
It's a new world, manipulating the photon on an everyday basis.
So, who knows what would be possible if we were able to capture the graviton And then manipulate it.
Gravity holds everything in our universe together.
But the gravity between anything but giant objects is incredibly weak.
A tiny action over here could never create a reaction over here.
Or could it? Distance.
It's such a basic idea, we don't even think about it.
But because we have distance, that object is too far away from me to knock over.
But now, suppose I had a double, someone I'm truly, deeply connected to.
I could cause something far away to happen instantly.
Could such a power exist in the universe? Quantum physicist Anton Zeilinger studies a strange phenomenon called entanglement.
Entanglement means that two particles which have interacted are connected in a very interesting way, such that measurement on one changes the quantum state of the other one.
The particles of the quantum world are as unpredictable as playing cards.
They can SPiN and vibrate in many possible directions.
When we measure these properties, we get random results.
But according to quantum theory, when two particles are entangled, their results will always match As if the particles could somehow talk to each other.
In a nutshell, we have two particles, and I make measurements on them.
The result on each of them is completely random.
But the two are the same.
How can two random events always be the same? Stranger still, entangled particles seem to remain connected, no matter how far apart they are.
The idea that objects must be nearby to affect each other is what physics calls locality.
So if you consider a stack of papers, then locality would mean that if I kick one over, the others also fall over.
But entanglement appears to be non-local, which means that distance is irrelevant.
Non-locality would mean that if these papers fall over by themselves, something else might happen like this picture falling over at the end of the room.
On the roof of his institute in Vienna, Anton has deployed a powerful laser to test entanglement over long distances.
What we do here is we create photon pairs.
We keep one photon locally and the other one is sent to a measurement station, which is about three miles away.
After moving his entangled photons far apart, Anton measures them both at the exact same time.
Every time he does this, he sees the same eerie coincidence.
Their particles give matching answers.
To see if it matters how far apart they are, Anton has performed this experiment over ranges longer than 90 miles.
If the theory of non-locality is correct, the connection between entangled particles is literally instantaneous, even if they're across the universe.
To one of the greatest minds of the 20th century, the idea of instant connections seemed to defy the laws of physics.
Einstein was always critical about quantum mechanics for two reasons.
One was the randomness of individual events, and the second was entanglement.
So, Anton set out to make sure this spooky action at a distance he saw in his experiments was a genuinely spooky force.
At Vienna's Hofburg palace, he found a sprawling subbasement that gave him room to work.
And we are here in the second basement, in the lowest basement, which we chose because it has long hallways.
These are the longest hallways in Vienna.
And, furthermore, the environment is very stable, very little vibrations, it's very quiet.
This hallway is so long that even light takes a full billionth of a second to cross it.
When Anton shoots entangled photons toward the opposite ends of this hallway, his super-fast equipment has time to measure both photons faster than light can beam a message between them.
We measure them really simultaneously.
So fast that there's no time that they could have talked to each other and told each other what happens.
Anton proved that entanglement makes an instant connection.
Somehow, two faraway places can be linked in a way that defies explanation.
Could a spooky distant force also affect us and the events in our lives? According to this man, it can.
In fact, it could be the reason reality exists.
We are made of tiny magic particles.
Entanglement gives every one of them the power to make connections that reach instantly across the universe.
But if the particles in our bodies can do this Why can't we do it ourselves? And why does our world look so Ordinary? If a mystical force is connecting distant points in the universe Where do we fit in? Good morning, Toronto.
Your weather forecast today, a 50 percent chance of rain.
Tiny quantum events are all around us, happening at every single moment.
Quantum physicist Aephraim Steinberg can't see them any better than the rest of us.
But he believes we feel the effects.
We all go and listen to the weather forecast, and at best, they tell us 50 percent chance of rain, 60 percent chance of rain.
We just don't know enough.
According to the standard view of quantum mechanics, there's a kind of quantum weather out there where we're always doomed to have predictions that are only probabilistic 50 percent chance of this, 50 percent chance of that.
According to Aephraim, there's reason to suspect we don't fully understand the quantum world.
And that reason is its randomness.
It's these random particles of the quantum world that can entangle with each other, making instantaneous connections.
We know that entanglement means there's a sort of hidden connection.
It's a mysterious kind of connection that we can't describe mechanistically.
No one understands why it should be that the universe seems capable of speaking to itself instantaneously across huge distances, while whenever we try to communicate, we're limited to speaking no faster than the speed of light.
If I leave home in my car in the morning and I get to work half an hour later, we all believe that you could tell me where my car was every instant of the way along that path.
Quantum mechanics is different.
It doesn't have this concept of a trajectory.
It was in a famous experiment called the double slit, where the trajectories of quantum particles first went missing.
In this experiment, light travels toward a pair of slits so that each photon, each particle of light, might be expected to choose either take the left slit or the right slit.
But offer a proton a choice of two slits, and it appears to choose both of them.
If it was a car, we could determine that car would either turn left or turn right.
It couldn't do both.
But cars and photons are different in another way.
You could watch a car, but you can't watch a photon.
So, we'd all love to see how the photon pulls off this trick.
But when you think about what it takes to observe something, you realize that there's no such thing as passive observation.
For you to see an object, you must bounce light off of it.
But if what you're trying to see is a particle of light You destroy what you're looking at.
The normal view of quantum mechanics is to say that we simply cannot ask which slit an individual particle goes through.
We can't talk about how they get from place to place.
All we can talk about is the probabilities for where they end up when we observe them at the end of the day.
While we move in predictable paths, we are made of particles that seem to skip around at random, or so quantum theory asks us to believe.
But it's not the only interpretation of what's happening.
Back in 1952, a physicist named David Bohm proposed that quantum particles might actually follow predictable paths, but only if we accept that faraway forces are shaping their trajectories.
Aephraim decided to investigate this idea.
He set out to redo the double-slit experiment, to see whether the faraway force called entanglement might offer a more sensible explanation of how particles move.
Nowadays, we have techniques that allow us to actually measure what a photon's doing while it's in flight.
We don't want to do this by catching the photon and interrupting its trajectory, if it has one.
Instead, we do it using the magic of entangled particles.
When two particles entangle, they become perfect mirrors of one another so one can tell you what the other is doing.
Imagine two cars that are identical in every way, even down to the turn signal.
Maybe as car "a" rides off into an intersection, we can't follow it and see which way it turns.
But we can always look at car "B.
" And if its right blinker is turning, we conclude that car "a" should turn to the right.
Like the two slits in the experiment, two roads lead away from this intersection.
Turn left, and you get to a church.
Turn right, and you get to a fountain.
Aephraim can't watch which road his car will choose But by watching the car it's entangled with He can guess its destination.
But, once again, protons aren't like cars.
Even knowing which way they turned will steer you wrong half the time.
Does randomness win the day after all, or is something happening after the intersection? Aephraim used entanglement to keep on watching.
It's as though even though I can't follow the car through the intersection and measure exactly where it is at every instance, I can get just a little bit of information about where it is now, where it is a moment later, and build up a trajectory.
As the photon moved toward its destination, Aephraim watched its entangled partner.
It didn't just tell him where the other photon went, it actually influenced the other's trajectory.
It was as if they were connected by an unseen force.
The two particles were collaborating to from a trajectory just like the ones we see.
We know based on the theory of entanglement that entangled particles are forever influencing one another.
To understand what one entangled car is doing, we must also know what the other entangled car is doing.
I can't lift up my hand and cause an apple on the other side of the quad to rise up off the ground.
And yet, the world is simply interconnected.
The universe seems to be busy talking to itself instantaneously all the time.
Remember how in "star wars," the force is with you, even if you aren't aware of it? While I stand here experiencing plain old reality, the particles I'm made of might be communicating with particles billions of light years away.
It's a magic trick we do in every moment.
And science is starting to get an idea how it works.
Hello.
Oh, you again.
Yeah, I was just hello? When we human communicate over distance, there has to be something connecting us, whether it's a phone line or a radio signal.
But entanglement doesn't seem to work that way.
It just happens.
There is no phone line.
Or, can we just not see the cord? Theoretical physicist Daniel Kabot thinks a lot about distant connections, and the hidden ways they might work.
Quantum entanglement is one of the most mysterious properties of quantum mechanics.
We might thing that two things that are widely separated have their own independent existence.
But according to quantum mechanics, that's really not true.
Objects don't have an independent existence of their own.
Quantum mechanics ties them all together.
In quantum mechanics, instant connections are everywhere, but we can't use those connections when we want to go somewhere.
We still have to walk.
Our concepts of distance and time are so fundamental that we don't think of them as concepts at all.
We think of them simply as reality the set of rules which everything in the universe must follow.
Hi, I called in an order.
All right.
Daniel.
Pastrami Reuben.
Excellent.
Thanks.
Enjoy.
If we want to get somewhere, we have to pass through space.
Forget the cheesecake.
If we change our minds about a lunch order Hello, junior's? We have to cross the same space again.
Can I get a slice of cheesecake? But according to some physicists, there are faster ways to go.
A wormhole is like a filament of space that connects in two distant points, not via the route that we'd normally travel.
It's a shortcut where you'd go out of our ordinary space and then reappear somewhere else.
Forgot my cheesecake.
Wormholes connect two distant places faster than light could move between them.
While there's no direct evidence wormholes exist, the same kind of connection links two entangled particles.
One idea is that this connection is actually a reflection of quantum entanglement.
Wormholes and quantum entanglement are very similar to each other could well be two different sides of the same coin.
Daniel thinks wormholes might be the secret shortcuts by which entangled particles communicate.
And if these connections exist, the universe may be filled with them.
You could think about the early universe as a hot, molten blob.
As it expanded and cooled, the space we see began to take form.
The surface of the globe is the universe we experience.
There is nothing inside or outside at least, that's the usual portrayal.
The early universe started out small, hot, and dense, filled with particles as they interacted with each other.
This created entanglements, quantum connections between the different particles that were present in the early universe.
And as the universe expanded, those connections weren't lost.
They left traces behind.
Like the threads passing through this globe, the hidden legacy of creation might be a network of wormholes.
But if wormholes are everywhere, why don't we sense their existence? Daniel thinks we do.
Let's imagine that we had a huge number of particles, all with quantum entanglement.
And then we'd have a very dense network of wormholes connecting all of these particles.
If you looked at that network and looked at it a bit from a distance, it might look to you very much like the space and time that we observe.
The space around us might be filled with hidden connections dating back to the creation of the universe.
But could new connections still be forming? One scientist thinks gravity itself could be making them In the universe's darkest places.
Two vastly different powers are at work in our universe.
While gravity can warp the space between distant galaxies, entanglement acts like space and distance do not exist.
Today, science is seeking a theory of everything that ties together gravity and the forces of the quantum world.
Could gravity and entanglement be manifestations of the same thing? Could there be a master force? For astrophysicist Damien Easson, the first step towards a theory of everything is a strange one figuring out what empty space is made of.
Nobody really knows what empty space is.
But we know that at least what we think of as empty space is filled with energy.
Damien works on a theory called loop quantum gravity, which contends that nothing is not really nothing.
The core idea in looped quantum gravity is that empty space itself is made out of small quantum bricks of nothing.
The size of these bricks is incredibly small much, much, much smaller than an electron or a proton or other particles that we know about.
But we believe nothing can actually collapse any smaller than that.
Physicists think a lot about collapsing because there are places in the universe where the force of gravity is said to crush things down to nothing.
Black holes are one of the great mysteries of science.
They form when massive stars run out of fuel.
Without the outward push of nuclear combustion, they collapse under the pull of their own gravity.
Around the black hole, the gravitational pull is so strong that even light can't escape hence, we call it a black hole.
Inside a black hole, many scientists think matter is crushed down to no size at all.
But how could that be possible if space itself is made of uncrushable bricks of nothing? In places like this junkyard, you'll find some powerful manmade forces.
This industrial size crusher applies more than a ton of pressure to every inch of the car inside.
But as the car gets more compacted, the machine becomes less and less effective.
Gravity is different.
If it was only up to gravity, this car would collapse and get smaller and smaller and smaller eventually, some people believe, so small that it would be an infinitely dense point.
And that's what we call a singularity.
If singularities are real, they'd be great places to make connections.
Inside one, the distance between things shrinks down to nothing.
Everything overlaps with everything else.
Distance and time simply cease to exist.
But could this actually happen in black holes? Damien is not certain.
When we fall into a black hole, according to conventional wisdom, the forces of gravity become so strong that things are ripped apart, and the laws of physics as we understand them, break down.
We know however, though, that since the singularity is an incredibly small space, some other theory, some theory of quantum gravity must have to kick in.
Black holes are like the clown cars of the universe, where everything gets uncomfortably close together.
Damien thinks that when the force of gravity meets the tiny quantum world, some funny things might happen.
All right, now imagine this part of the balloon represents the space inside of a black hole.
If we fall into the black hole, gravity becomes stronger and stronger.
Space becomes more and more compressed.
And this is the point where a passageway opens up into a new universe.
The passage between the old universe and the new universe is what we call a wormhole.
Where some people see a singularity, Damien sees a wormhole, a secret door to another realm.
While we know gravity brings things close together, it may also do what entanglement does build connections between distant places.
According to this theory, entanglement and gravity may work together as a single force, connecting everything and joining our universe with many other ones.
We believe that there are black holes on the inside of all the hundred billion galaxies that we observe.
It's quite possible then that within each of these black holes is an entirely new universe, connected to our universe by a wormhole.
Our universe may be just one among billions all bound together by a single master force.
But this scientist thinks that same force also unites all time, and we could use it to send messages to the future.
Ever have that feeling that the past isn't really gone? Or that someone you've lost is right here with you? Those mysterious feelings of connection are what keep fortune tellers in business.
But entanglement and gravity tell us things are eerily connected.
In "star wars," you can use the force to hear the voices of people who aren't here anymore.
When we feel the presence of things gone by, have they really gone by? Or are they still with us? Hut, hut! Boise state physicist Jay Olson thinks we never walk alone, because in the entangled universe, everything that has ever happened is still with us.
So, this stadium is almost half a century old.
Teams have played here, many games have been won and lost.
Just being around it, you can feel that there's a lot of history that has played out here.
Tackle him! Three, 32.
Jay likes to watch football scrimmages.
He doesn't attend them religiously, but the way he understands the universe, you don't have to.
Go to just one scrimmage, and you'll experience many others.
The universe is all of space and all of time simultaneously.
It's the past that's correlated with the future, and so that information never really goes away.
It's always encoded throughout all time.
Five! Set, hut! Think of the universe at this very moment like this stadium vast, cold, and virtually empty.
A really big game, the big bang itself, happened here 13 billion years ago.
A lot of entanglement was generated early on.
Because the density was high, there were lots of particles bumping into each other, flying off, carrying these deeper than normal connections.
And as the universe spreads out, the matter spreads out, too, even these particles that are separated by vast distances can still be entangled with one another.
And after the big bang, the connections keep on multiplying as entangled particles swap their experiences.
To swap entanglement in the lab, scientists start with two pairs of entangled particles.
By introducing just one particle from each pair, they can entangled their distant partners.
You could think of this in terms of human couples.
Jay met his wife, ping, because they were in the same town at the same time.
They decided to get entangled.
But ping sometimes skips the football scrimmages.
Now, suppose things get exciting at a particular practice And Jay entangles with his neighbor.
Not only are they linked, but so are the partners they were entangled with.
Even though they've never met each other, they are now instantly connected.
Weirder still, connections like this can form between the future and the past.
Entanglements don't just cross space.
They can also cross time.
And we call this time-like entanglement.
Suppose it was 10 years earlier.
Jay's football buddy was entangled back then, but Jay wasn't.
Fast-forward 10 years, and a lot of things are different.
Jay met ping, while his buddy got divorced.
Our human perspective says we can only share an experience if we are there at the same time.
That moment wouldn't affect your wives at all.
Especially if one of you is no longer married.
But to entanglement, time doesn't matter.
It simply connects one wife from the present with the other from the past.
This is true even though they never had the opportunity to meet.
And something that happened to buddy's ex 10 years ago could happen to my wife today.
Yeah! Whoo! The entangled universe is an timeless place where the present is deeply connected to the future and the past.
Jay thinks we could see those connections if we built a special detector.
It's possible to generate a detector that kind of looks at time slightly differently.
It doesn't see exactly what your eye sees, it sees something else.
Like a Jedi uses the force to see people who aren't here anymore, we, too, could see the instantaneous links uniting all of time.
And Jay thinks we could tap this hidden network.
What we know is that this an interesting property that nature is giving us.
You could send information into the future while skipping the time in between.
To send his message across time, Jay would encode it in a quantum state and pass it to a particle entangled with the future.
The message disappears, but it's not gone.
It's merely skipping over what we humans experience as time.
It could be two billion years or it could be two years.
We could say two years if I want to be around to see it.
Two years later Omaha! Its moment is approaching.
Hut.
With her special detector, ping can now receive the message Jay left for her two years ago.
If we can send messages across time, could we some day send ourselves? The fact that that entanglement exists between time, people have barely begun to think of what that might be able to do.
If you could send the state of one atom, in principle, you could do two or 10 or a million or even an entire human body or mind.
Will we some day harness the power to skip across time and space? Or the power to move distant objects without ever touching them? Sounds like make-believe, but such powers do exist.
And they're already at work inside us.
As we seek to understand gravity and entanglement, we are taking our first steps toward abilities we have only dreamed about, toward deeper understanding of our oneness with the universe.
There may be no such thing as the force in "star wars" But we have our own that's just as amazing.
The force is truly with us.
Or is it? New research is beginning to unveil a hidden force, one that shakes the entire universe and penetrates space with trillions of invisible connections Instantly linking every place in our world and joining our future with our past.
Now we're beginning to grasp these mystical powers.
Is the force With us? Space, time, life itself.
The secrets of the cosmos lie through the wormhole.
Captions by vitac captions paid for by discovery communications you know the story.
A long time ago in a galaxy far, far away, there was a mysterious force, surrounding us, penetrating us, binding the galaxy together.
If you could wield this force You could do astonishing things.
Seem like a Hollywood fantasy? Well, scientists now wonder whether something like the force could be real.
Could there actually be a mystical power that spans the universe, connecting and binding all things? Astrophysicist Jamie Rollins has spent his career listening to the universe, trying to detect a mysterious force one we've never been able to see.
Over the course of the history of astronomy, light has essentially been our only way of learning about the universe.
What we see out there is influenced by forces coming from things that we don't actually directly observe.
It's like walking around without being able to hear.
We know that there are sounds, and we know that we could learn a lot from them if we could hear them.
There is no sound in the vacuum of space.
But according to Albert Einstein, gravity affects space in a very similar way to sound.
We've been able to demonstrate many of the predictions of Einstein's general theory of gravity.
The one big one that we haven't is the fact that there should be waves of gravity.
Gravitational waves are one of Einstein's most elusive predictions.
He believed that space is not truly empty, but acts like a kind of substance that can be warped by masses like stars and galaxies.
And when massive objects move suddenly, they send ripples across space, squeezing and stretching everything they encounter from planets to the people living on them.
Detecting these gravitational waves would prove that we are physically joined to the cosmos by a fabric of space, and that events across the universe exert a tangible force on us.
But detecting this force is no easy task.
The waves that pass through the Earth are essentially unfathomably small.
We have to make incredibly sensitive detectors to be able to experience this effect.
LIGO the laser interferometer gravitational-wave observatory is one of the world's biggest scientific experiments.
Each of its arms is four full kilometers long.
To rule out Earthquakes and other forces, LIGO has two separate detectors one in Louisiana, one in Washington state.
LIGO compares the way two high-powered laser beams move up and down each of its long arms.
Mirrors at the end of each one bounce the laser beams back to the center, where they're compared by computers.
As long as the length of the two arms are exactly the same, then the light going into the two arms will come back and be exactly in synch.
If a gravitational wave passes through the Earth, it would cause the arms to squeeze and stretch, throwing the lasers out of phase with each other.
Jamie is one of LIGO's more than 1,000 scientists.
And, for him, the principle by which the detector works is very familiar.
As a former DJ, he's used to listening to tiny discrepancies in sounds.
Let's say I've got two identical records that I've started at the exact same time such that the songs are exactly synchronized together.
If we were to disturb one by, say, dragging my finger along the side, then this record would fall out of phase with the other one, which would produce a shift in the sound that we can hear.
If you're listening to one record, you might not notice that effect.
Now if we were to speed up on record and slow down the other, the songs come in and out of phase with each other.
This is very similar to what happens to the light in the arms of the interferometer.
The changes in length that we're looking for are so miniscule.
They're smaller than the nucleus of a single atom.
It's completely imperceptible to the normal physical world that we experience.
But in September 2015, after more than two decades of development and more than a billion dollars, LIGO finally detected a ripple in space.
It sensed a staggeringly violent event, one that took place a long time ago in a galaxy a billion light years away.
What we detected was a binary black hole system which is two black holes that are in a tight orbit around each other in fact, at the very end of their lifetime as a binary system.
As the two black holes spiraled together and collided, the fabric of space shuddered and a billion years later, LIGO felt it.
To Jamie, that ripple in space is proof that gravity connects everything in the universe.
It was incredibly gratifying.
But it's also the excitement to know that there's so much to be learned by having this new sensory perception in the universe.
It's really as if we're connected to the rest of the universe in a totally different way.
One omnipresent force, the force of gravity, binds the universe together.
But how does gravity actually connect planets, stars, and people? Cosmologist Claudia De Rham is taking aim at the elusive substance of gravity itself.
For all the forces that we know, there's a particle associated with that force, which is responsible for carrying the force through empty space.
When I bring that magnet close to the horseshoe, I can feel the magnetic force.
And for the magnetic force, the electric force, the particle is the photon.
It's not visible light, but it's there nonetheless.
And one of the great mysteries of physics today is whether there's a particle associated with the gravitational force.
Claudia is obsessed with finding gravity's hidden mechanism.
How does this mysterious force stretch across the cosmos, silently tugging on everything? But gravity is not easy to study.
Because of all the forces we know, gravity is the weakest.
We think of gravity as this huge, powerful force that keeps us glued to the surface of the Earth.
But, actually, it's remarkably easy to overcome.
All it takes is a few fans.
Right now, a powerful wind is pushing Claudia away from the Earth.
Molecules of air are hitting her body and forcing it upward.
But something else is forcing her down.
You could almost picture a tractor beam pulling me down.
And if anything is, in physics, we're having a huge debate on whether gravity is a force or not.
According to Einstein, there is no force of gravity pulling on these skydivers.
The huge mass of the Earth simply distorts the shape of space near it, and they follow the contours of that shape.
But quantum mechanics has a different approach.
According to this theory of the most fundamental particles, something really is passing between the skydivers and the Earth identical little chunks of gravity called gravitons.
Right now, I'm exchanging gravitons with the Earth.
They are traveling between the Earth and me.
If we could see gravitons, we'd see tractor beams everywhere, making hidden connections between everything that has mass.
Claudia believes these graviton tractor beams keep us all stuck to the Earth at least, when we're not in a wind tunnel.
But they have never been detected in any scientific experiment.
It's extremely hard to catch a graviton.
When a graviton comes, it just goes straight through me.
To detect the particles which carry forces, we build particle accelerators.
But if those forces are weak, we must build enormous particle accelerators, and gravity is trillions of times weaker than electromagnetism.
You could think of needing to have a detector of the massive Jupiter parked in orbit around a neutron star to have enough mass there to have maybe the chance of detecting one or two gravitons every century, and that's being very optimistic.
But if we could find the graviton and learn to manipulate it, we'd have in our hands a seemingly supernatural force.
Just as we focused photons into laser beams, we could focus gravitons into beams of gravity.
It's a new world, manipulating the photon on an everyday basis.
So, who knows what would be possible if we were able to capture the graviton And then manipulate it.
Gravity holds everything in our universe together.
But the gravity between anything but giant objects is incredibly weak.
A tiny action over here could never create a reaction over here.
Or could it? Distance.
It's such a basic idea, we don't even think about it.
But because we have distance, that object is too far away from me to knock over.
But now, suppose I had a double, someone I'm truly, deeply connected to.
I could cause something far away to happen instantly.
Could such a power exist in the universe? Quantum physicist Anton Zeilinger studies a strange phenomenon called entanglement.
Entanglement means that two particles which have interacted are connected in a very interesting way, such that measurement on one changes the quantum state of the other one.
The particles of the quantum world are as unpredictable as playing cards.
They can SPiN and vibrate in many possible directions.
When we measure these properties, we get random results.
But according to quantum theory, when two particles are entangled, their results will always match As if the particles could somehow talk to each other.
In a nutshell, we have two particles, and I make measurements on them.
The result on each of them is completely random.
But the two are the same.
How can two random events always be the same? Stranger still, entangled particles seem to remain connected, no matter how far apart they are.
The idea that objects must be nearby to affect each other is what physics calls locality.
So if you consider a stack of papers, then locality would mean that if I kick one over, the others also fall over.
But entanglement appears to be non-local, which means that distance is irrelevant.
Non-locality would mean that if these papers fall over by themselves, something else might happen like this picture falling over at the end of the room.
On the roof of his institute in Vienna, Anton has deployed a powerful laser to test entanglement over long distances.
What we do here is we create photon pairs.
We keep one photon locally and the other one is sent to a measurement station, which is about three miles away.
After moving his entangled photons far apart, Anton measures them both at the exact same time.
Every time he does this, he sees the same eerie coincidence.
Their particles give matching answers.
To see if it matters how far apart they are, Anton has performed this experiment over ranges longer than 90 miles.
If the theory of non-locality is correct, the connection between entangled particles is literally instantaneous, even if they're across the universe.
To one of the greatest minds of the 20th century, the idea of instant connections seemed to defy the laws of physics.
Einstein was always critical about quantum mechanics for two reasons.
One was the randomness of individual events, and the second was entanglement.
So, Anton set out to make sure this spooky action at a distance he saw in his experiments was a genuinely spooky force.
At Vienna's Hofburg palace, he found a sprawling subbasement that gave him room to work.
And we are here in the second basement, in the lowest basement, which we chose because it has long hallways.
These are the longest hallways in Vienna.
And, furthermore, the environment is very stable, very little vibrations, it's very quiet.
This hallway is so long that even light takes a full billionth of a second to cross it.
When Anton shoots entangled photons toward the opposite ends of this hallway, his super-fast equipment has time to measure both photons faster than light can beam a message between them.
We measure them really simultaneously.
So fast that there's no time that they could have talked to each other and told each other what happens.
Anton proved that entanglement makes an instant connection.
Somehow, two faraway places can be linked in a way that defies explanation.
Could a spooky distant force also affect us and the events in our lives? According to this man, it can.
In fact, it could be the reason reality exists.
We are made of tiny magic particles.
Entanglement gives every one of them the power to make connections that reach instantly across the universe.
But if the particles in our bodies can do this Why can't we do it ourselves? And why does our world look so Ordinary? If a mystical force is connecting distant points in the universe Where do we fit in? Good morning, Toronto.
Your weather forecast today, a 50 percent chance of rain.
Tiny quantum events are all around us, happening at every single moment.
Quantum physicist Aephraim Steinberg can't see them any better than the rest of us.
But he believes we feel the effects.
We all go and listen to the weather forecast, and at best, they tell us 50 percent chance of rain, 60 percent chance of rain.
We just don't know enough.
According to the standard view of quantum mechanics, there's a kind of quantum weather out there where we're always doomed to have predictions that are only probabilistic 50 percent chance of this, 50 percent chance of that.
According to Aephraim, there's reason to suspect we don't fully understand the quantum world.
And that reason is its randomness.
It's these random particles of the quantum world that can entangle with each other, making instantaneous connections.
We know that entanglement means there's a sort of hidden connection.
It's a mysterious kind of connection that we can't describe mechanistically.
No one understands why it should be that the universe seems capable of speaking to itself instantaneously across huge distances, while whenever we try to communicate, we're limited to speaking no faster than the speed of light.
If I leave home in my car in the morning and I get to work half an hour later, we all believe that you could tell me where my car was every instant of the way along that path.
Quantum mechanics is different.
It doesn't have this concept of a trajectory.
It was in a famous experiment called the double slit, where the trajectories of quantum particles first went missing.
In this experiment, light travels toward a pair of slits so that each photon, each particle of light, might be expected to choose either take the left slit or the right slit.
But offer a proton a choice of two slits, and it appears to choose both of them.
If it was a car, we could determine that car would either turn left or turn right.
It couldn't do both.
But cars and photons are different in another way.
You could watch a car, but you can't watch a photon.
So, we'd all love to see how the photon pulls off this trick.
But when you think about what it takes to observe something, you realize that there's no such thing as passive observation.
For you to see an object, you must bounce light off of it.
But if what you're trying to see is a particle of light You destroy what you're looking at.
The normal view of quantum mechanics is to say that we simply cannot ask which slit an individual particle goes through.
We can't talk about how they get from place to place.
All we can talk about is the probabilities for where they end up when we observe them at the end of the day.
While we move in predictable paths, we are made of particles that seem to skip around at random, or so quantum theory asks us to believe.
But it's not the only interpretation of what's happening.
Back in 1952, a physicist named David Bohm proposed that quantum particles might actually follow predictable paths, but only if we accept that faraway forces are shaping their trajectories.
Aephraim decided to investigate this idea.
He set out to redo the double-slit experiment, to see whether the faraway force called entanglement might offer a more sensible explanation of how particles move.
Nowadays, we have techniques that allow us to actually measure what a photon's doing while it's in flight.
We don't want to do this by catching the photon and interrupting its trajectory, if it has one.
Instead, we do it using the magic of entangled particles.
When two particles entangle, they become perfect mirrors of one another so one can tell you what the other is doing.
Imagine two cars that are identical in every way, even down to the turn signal.
Maybe as car "a" rides off into an intersection, we can't follow it and see which way it turns.
But we can always look at car "B.
" And if its right blinker is turning, we conclude that car "a" should turn to the right.
Like the two slits in the experiment, two roads lead away from this intersection.
Turn left, and you get to a church.
Turn right, and you get to a fountain.
Aephraim can't watch which road his car will choose But by watching the car it's entangled with He can guess its destination.
But, once again, protons aren't like cars.
Even knowing which way they turned will steer you wrong half the time.
Does randomness win the day after all, or is something happening after the intersection? Aephraim used entanglement to keep on watching.
It's as though even though I can't follow the car through the intersection and measure exactly where it is at every instance, I can get just a little bit of information about where it is now, where it is a moment later, and build up a trajectory.
As the photon moved toward its destination, Aephraim watched its entangled partner.
It didn't just tell him where the other photon went, it actually influenced the other's trajectory.
It was as if they were connected by an unseen force.
The two particles were collaborating to from a trajectory just like the ones we see.
We know based on the theory of entanglement that entangled particles are forever influencing one another.
To understand what one entangled car is doing, we must also know what the other entangled car is doing.
I can't lift up my hand and cause an apple on the other side of the quad to rise up off the ground.
And yet, the world is simply interconnected.
The universe seems to be busy talking to itself instantaneously all the time.
Remember how in "star wars," the force is with you, even if you aren't aware of it? While I stand here experiencing plain old reality, the particles I'm made of might be communicating with particles billions of light years away.
It's a magic trick we do in every moment.
And science is starting to get an idea how it works.
Hello.
Oh, you again.
Yeah, I was just hello? When we human communicate over distance, there has to be something connecting us, whether it's a phone line or a radio signal.
But entanglement doesn't seem to work that way.
It just happens.
There is no phone line.
Or, can we just not see the cord? Theoretical physicist Daniel Kabot thinks a lot about distant connections, and the hidden ways they might work.
Quantum entanglement is one of the most mysterious properties of quantum mechanics.
We might thing that two things that are widely separated have their own independent existence.
But according to quantum mechanics, that's really not true.
Objects don't have an independent existence of their own.
Quantum mechanics ties them all together.
In quantum mechanics, instant connections are everywhere, but we can't use those connections when we want to go somewhere.
We still have to walk.
Our concepts of distance and time are so fundamental that we don't think of them as concepts at all.
We think of them simply as reality the set of rules which everything in the universe must follow.
Hi, I called in an order.
All right.
Daniel.
Pastrami Reuben.
Excellent.
Thanks.
Enjoy.
If we want to get somewhere, we have to pass through space.
Forget the cheesecake.
If we change our minds about a lunch order Hello, junior's? We have to cross the same space again.
Can I get a slice of cheesecake? But according to some physicists, there are faster ways to go.
A wormhole is like a filament of space that connects in two distant points, not via the route that we'd normally travel.
It's a shortcut where you'd go out of our ordinary space and then reappear somewhere else.
Forgot my cheesecake.
Wormholes connect two distant places faster than light could move between them.
While there's no direct evidence wormholes exist, the same kind of connection links two entangled particles.
One idea is that this connection is actually a reflection of quantum entanglement.
Wormholes and quantum entanglement are very similar to each other could well be two different sides of the same coin.
Daniel thinks wormholes might be the secret shortcuts by which entangled particles communicate.
And if these connections exist, the universe may be filled with them.
You could think about the early universe as a hot, molten blob.
As it expanded and cooled, the space we see began to take form.
The surface of the globe is the universe we experience.
There is nothing inside or outside at least, that's the usual portrayal.
The early universe started out small, hot, and dense, filled with particles as they interacted with each other.
This created entanglements, quantum connections between the different particles that were present in the early universe.
And as the universe expanded, those connections weren't lost.
They left traces behind.
Like the threads passing through this globe, the hidden legacy of creation might be a network of wormholes.
But if wormholes are everywhere, why don't we sense their existence? Daniel thinks we do.
Let's imagine that we had a huge number of particles, all with quantum entanglement.
And then we'd have a very dense network of wormholes connecting all of these particles.
If you looked at that network and looked at it a bit from a distance, it might look to you very much like the space and time that we observe.
The space around us might be filled with hidden connections dating back to the creation of the universe.
But could new connections still be forming? One scientist thinks gravity itself could be making them In the universe's darkest places.
Two vastly different powers are at work in our universe.
While gravity can warp the space between distant galaxies, entanglement acts like space and distance do not exist.
Today, science is seeking a theory of everything that ties together gravity and the forces of the quantum world.
Could gravity and entanglement be manifestations of the same thing? Could there be a master force? For astrophysicist Damien Easson, the first step towards a theory of everything is a strange one figuring out what empty space is made of.
Nobody really knows what empty space is.
But we know that at least what we think of as empty space is filled with energy.
Damien works on a theory called loop quantum gravity, which contends that nothing is not really nothing.
The core idea in looped quantum gravity is that empty space itself is made out of small quantum bricks of nothing.
The size of these bricks is incredibly small much, much, much smaller than an electron or a proton or other particles that we know about.
But we believe nothing can actually collapse any smaller than that.
Physicists think a lot about collapsing because there are places in the universe where the force of gravity is said to crush things down to nothing.
Black holes are one of the great mysteries of science.
They form when massive stars run out of fuel.
Without the outward push of nuclear combustion, they collapse under the pull of their own gravity.
Around the black hole, the gravitational pull is so strong that even light can't escape hence, we call it a black hole.
Inside a black hole, many scientists think matter is crushed down to no size at all.
But how could that be possible if space itself is made of uncrushable bricks of nothing? In places like this junkyard, you'll find some powerful manmade forces.
This industrial size crusher applies more than a ton of pressure to every inch of the car inside.
But as the car gets more compacted, the machine becomes less and less effective.
Gravity is different.
If it was only up to gravity, this car would collapse and get smaller and smaller and smaller eventually, some people believe, so small that it would be an infinitely dense point.
And that's what we call a singularity.
If singularities are real, they'd be great places to make connections.
Inside one, the distance between things shrinks down to nothing.
Everything overlaps with everything else.
Distance and time simply cease to exist.
But could this actually happen in black holes? Damien is not certain.
When we fall into a black hole, according to conventional wisdom, the forces of gravity become so strong that things are ripped apart, and the laws of physics as we understand them, break down.
We know however, though, that since the singularity is an incredibly small space, some other theory, some theory of quantum gravity must have to kick in.
Black holes are like the clown cars of the universe, where everything gets uncomfortably close together.
Damien thinks that when the force of gravity meets the tiny quantum world, some funny things might happen.
All right, now imagine this part of the balloon represents the space inside of a black hole.
If we fall into the black hole, gravity becomes stronger and stronger.
Space becomes more and more compressed.
And this is the point where a passageway opens up into a new universe.
The passage between the old universe and the new universe is what we call a wormhole.
Where some people see a singularity, Damien sees a wormhole, a secret door to another realm.
While we know gravity brings things close together, it may also do what entanglement does build connections between distant places.
According to this theory, entanglement and gravity may work together as a single force, connecting everything and joining our universe with many other ones.
We believe that there are black holes on the inside of all the hundred billion galaxies that we observe.
It's quite possible then that within each of these black holes is an entirely new universe, connected to our universe by a wormhole.
Our universe may be just one among billions all bound together by a single master force.
But this scientist thinks that same force also unites all time, and we could use it to send messages to the future.
Ever have that feeling that the past isn't really gone? Or that someone you've lost is right here with you? Those mysterious feelings of connection are what keep fortune tellers in business.
But entanglement and gravity tell us things are eerily connected.
In "star wars," you can use the force to hear the voices of people who aren't here anymore.
When we feel the presence of things gone by, have they really gone by? Or are they still with us? Hut, hut! Boise state physicist Jay Olson thinks we never walk alone, because in the entangled universe, everything that has ever happened is still with us.
So, this stadium is almost half a century old.
Teams have played here, many games have been won and lost.
Just being around it, you can feel that there's a lot of history that has played out here.
Tackle him! Three, 32.
Jay likes to watch football scrimmages.
He doesn't attend them religiously, but the way he understands the universe, you don't have to.
Go to just one scrimmage, and you'll experience many others.
The universe is all of space and all of time simultaneously.
It's the past that's correlated with the future, and so that information never really goes away.
It's always encoded throughout all time.
Five! Set, hut! Think of the universe at this very moment like this stadium vast, cold, and virtually empty.
A really big game, the big bang itself, happened here 13 billion years ago.
A lot of entanglement was generated early on.
Because the density was high, there were lots of particles bumping into each other, flying off, carrying these deeper than normal connections.
And as the universe spreads out, the matter spreads out, too, even these particles that are separated by vast distances can still be entangled with one another.
And after the big bang, the connections keep on multiplying as entangled particles swap their experiences.
To swap entanglement in the lab, scientists start with two pairs of entangled particles.
By introducing just one particle from each pair, they can entangled their distant partners.
You could think of this in terms of human couples.
Jay met his wife, ping, because they were in the same town at the same time.
They decided to get entangled.
But ping sometimes skips the football scrimmages.
Now, suppose things get exciting at a particular practice And Jay entangles with his neighbor.
Not only are they linked, but so are the partners they were entangled with.
Even though they've never met each other, they are now instantly connected.
Weirder still, connections like this can form between the future and the past.
Entanglements don't just cross space.
They can also cross time.
And we call this time-like entanglement.
Suppose it was 10 years earlier.
Jay's football buddy was entangled back then, but Jay wasn't.
Fast-forward 10 years, and a lot of things are different.
Jay met ping, while his buddy got divorced.
Our human perspective says we can only share an experience if we are there at the same time.
That moment wouldn't affect your wives at all.
Especially if one of you is no longer married.
But to entanglement, time doesn't matter.
It simply connects one wife from the present with the other from the past.
This is true even though they never had the opportunity to meet.
And something that happened to buddy's ex 10 years ago could happen to my wife today.
Yeah! Whoo! The entangled universe is an timeless place where the present is deeply connected to the future and the past.
Jay thinks we could see those connections if we built a special detector.
It's possible to generate a detector that kind of looks at time slightly differently.
It doesn't see exactly what your eye sees, it sees something else.
Like a Jedi uses the force to see people who aren't here anymore, we, too, could see the instantaneous links uniting all of time.
And Jay thinks we could tap this hidden network.
What we know is that this an interesting property that nature is giving us.
You could send information into the future while skipping the time in between.
To send his message across time, Jay would encode it in a quantum state and pass it to a particle entangled with the future.
The message disappears, but it's not gone.
It's merely skipping over what we humans experience as time.
It could be two billion years or it could be two years.
We could say two years if I want to be around to see it.
Two years later Omaha! Its moment is approaching.
Hut.
With her special detector, ping can now receive the message Jay left for her two years ago.
If we can send messages across time, could we some day send ourselves? The fact that that entanglement exists between time, people have barely begun to think of what that might be able to do.
If you could send the state of one atom, in principle, you could do two or 10 or a million or even an entire human body or mind.
Will we some day harness the power to skip across time and space? Or the power to move distant objects without ever touching them? Sounds like make-believe, but such powers do exist.
And they're already at work inside us.
As we seek to understand gravity and entanglement, we are taking our first steps toward abilities we have only dreamed about, toward deeper understanding of our oneness with the universe.
There may be no such thing as the force in "star wars" But we have our own that's just as amazing.
The force is truly with us.