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In the beginning,
there was darkness...
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and then, bang...
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giving birth to an endless
expanding existence...
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of time, space, and matter.
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Now, see further
than we've ever imagined...
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beyond the limits of our existence...
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in a place we call "The Universe. "
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Our infinite universe is brimming
with strange, violent...
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and potentially
life-transporting phenomena.
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Imagine, cosmic portals where
objects could disappear, be ejected...
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or escape to some other place
in space or time.
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They are tickets to oblivion
for the most part.
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Either you get shredded
in a black hole...
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you get transported to another
part of the universe in a wormhole...
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or you get obliterated
by the gusher of the white hole.
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Blast off to the warped side
of the universe...
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as scientists search for black holes,
white holes, and wormholes.
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Are they frivolous fantasies
or a science fact?
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The universe
is a cosmic cornucopia...
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of endless possibilities.
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Imagine, a shuttle service
to anywhere in the cosmos.
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It's not aboard
a futuristic spaceship.
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It's a galactic ride
through a wormhole...
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a theoretical tunnel providing
shortcuts through space and time.
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Wormholes are a little bit
like a subway system...
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that you might use in the city,
where you're going into a hole...
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you go through a tunnel...
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and then you come out at the
other end through another hole...
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and then you've traveled
through the city.
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Same thing would be possible
in a wormhole...
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to travel between
different points in the universe.
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Physicist Clifford Johnson...
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has contemplated
the possibility of wormholes.
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The difference between a wormhole
and a subway system...
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is that you're using
the wormhole...
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to travel a greater distance
than you would...
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if you were traveling
in ordinary space.
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In theory,
a wormhole has a throat...
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connected to an entrance
and exit called mouths...
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located in different
parts of space.
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A wormhole is appealing...
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because we're limited
by the speed of light.
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We can't get
to the Andromeda galaxy...
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in less than something
like 600,000 years...
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even moving
at the speed of light.
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I keep wondering if the really
next big discovery in astronomy...
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could be a wormhole.
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Not just because they're fun
for people like me...
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but because they
could take us to someplace...
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that we can't plausibly
ever get any other way.
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Gregory Benford has pondered...
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the science and fiction
of outer space.
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As both a physicist and author
of over thirty sci-fi novels...
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Benford has witnessed fantastical
theories become a reality.
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A lot of us would like to know
if wormholes really exist...
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or whether they're just another
mathematical construct...
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thought up by Einstein,
the genius.
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Albert Einstein's
general relativity laws...
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allow for the existence
of wormholes.
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In 1930, Einstein
and his colleague, Nathan Rosen...
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calculated the mathematics
of one of these intergalactic pipelines.
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It became known as
the Einstein-Rosen bridge.
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The wormhole is a solution
of Einstein's equations...
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for general relativity,
telling us how gravity works.
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They're hypothetical,
and what they do...
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is they connect different
parts of space and time.
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The Einstein-Rosen
mathematical wormhole...
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arose from studying black holes.
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A black hole is a region in space
of extremely strong gravity.
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The gravity is so strong...
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that there is no way
for objects that get too near...
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to break away
from its gravitational pull.
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Nothing can escape
a close encounter with a black hole...
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not even light.
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This inverted fountain
serves as a visual analogy...
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to what's going on
around a black hole.
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At the bottom is the area
inside the event horizon...
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and the water falling
into it is analogous to gas...
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that might fall
into a black hole.
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Imagine yourself being a fish
swimming around this region.
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Once you get down inside
this central portion...
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you're past the point
of no return.
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But Einstein never
intended his wormhole...
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as a tool for space travel.
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His wormhole is theoretically
created at some moment of time.
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It opens up briefly,
then pinches off.
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Anything that tries
to pass through it...
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will get crushed
when it squeezes apart.
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A typical wormhole
that you write down...
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in your equations
and study is unstable.
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It'll vanish
in an incredibly short time.
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So what you need is
some means of holding it open.
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After Einstein's wormhole was
determined unstable in the 1960s...
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little research was done
on the concept.
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Then the sci-fi film "Contact"
was released in the late 1990s.
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Based on the book by
renowned astronomer Carl Sagan...
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it proposed that a wormhole
could be used for space travel.
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The book "Contact," and then
subsequently the movie...
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was a nice place in fiction
that was accessible to everyone...
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where you could see
the idea of a wormhole.
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So it was a nice way
of getting people...
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interested in that idea
all over again.
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This was kind
of a very far-fetched idea...
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that wasn't even considered
very seriously by many physicists...
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until Carl Sagan decided
to write this book...
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and try to make it
as realistic as possible.
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And since that time,
theoretical physicists...
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studying Einstein's
general theory of relativity...
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have considered travel
through wormholes.
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Scientists began
to investigate...
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whether there might be
a type of wormhole...
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different from Einstein's
that is traversable.
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But traversable wormholes
needed something...
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to prevent them
from pinching off.
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You want to stabilize
the wormhole.
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You don't want the wormhole
to collapse.
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Keep the wormhole open.
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That requires something new called
negative matter or exotic matter.
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We've never seen
negative matter before.
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It would have
anti-gravitational properties.
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But one day, if we ever
find negative matter...
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perhaps that's the key
to stabilize the wormhole.
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The idea
of a traversable wormhole...
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captivated science fiction
enthusiasts.
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It also reinvigorated
the serious study of wormholes...
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within the science community.
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This transversable wormhole
created quite a sensation...
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'cause perhaps
it is physically possible...
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to one day build a subway system
to another galaxy.
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The term wormhole came
from an analogy with an apple.
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You want to get from one part
of the apple to another part.
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If you're a worm...
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you can eat your way down
into the body of the apple...
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and make a little tunnel
and come out the other way...
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and it's shorter.
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But unlike a worm
moving here on this apple...
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for a wormhole
in our universe...
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we might not know what dangers lie
at the other end of the wormhole.
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The other end of a wormhole
could be connected...
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to a very dangerous
part of the universe...
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with all sorts
of exotic phenomena.
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It might even be
in the core of a star.
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If we ever find a wormhole...
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and if it's close enough
for us to reach...
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almost certainly we'll first send
automated probes through...
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and direct them to come back.
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Maybe even put them
on a cable...
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in case something nasty
happens to them...
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and they can't return.
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Physicists do not know
of any way that a wormhole...
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00:09:02,792 --> 00:09:05,502
might arise naturally
in our universe.
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00:09:06,921 --> 00:09:09,506
But can they be made artificially?
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00:09:11,801 --> 00:09:14,094
One possibility that
physicists speculated about...
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that might allow you
to construct wormholes...
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would be to blow them up...
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from what's considered to be
the fabric of space-time...
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that might actually
contain tiny wormholes...
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seething in and out of existence...
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due to the laws
of quantum mechanics.
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Scientists proposed that
perhaps traversable wormholes...
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could be sculpted out
of quantum foam...
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a subatomic
bubble-like structure...
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that might exist everywhere
in the universe.
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On length scales, a billion,
trillion times smaller...
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than the nucleus of an atom.
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That's how you would do it
in principle.
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It's completely unfeasible...
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using any technology
that we know of...
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but it's at least something
you might consider.
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If one could be engineered
or located in space...
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scientists contemplated
other possibilities for a wormhole.
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Could it transport
galactic vacationers...
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to different points in time...
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as well
as different places in space?
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To actually create a time machine
or a wormhole machine...
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that would take us
to a distant galaxy...
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you would have
to have the physics...
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of an advanced civilization...
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a civilization perhaps
millions of years beyond ours.
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00:10:36,636 --> 00:10:43,266
Time machines have mystified
movie audiences for over fifty years.
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Gentlemen, I am talking
about traveling through time...
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in a machine constructed
for that very purpose.
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00:10:53,402 --> 00:10:56,404
But could a wormhole
be used for such travel?
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The wormhole
may lead to things...
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like being able to go
to another galaxy...
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by walking five feet
through a wormhole...
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or even going to another time.
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00:11:11,837 --> 00:11:15,799
But wormholes as time machines
pose unsettling questions.
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In the distant future, will earthlings
be able to travel to the past...
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00:11:21,806 --> 00:11:24,182
and perhaps change history?
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00:11:33,234 --> 00:11:36,861
Scientific ideas considered
far-fetched today...
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could one day become
as acceptable...
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as the fact that
the Earth is round.
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The laws of physics may allow
for the existence of wormholes...
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00:11:50,710 --> 00:11:55,463
tunnels providing shortcuts
through space as well as time.
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00:11:58,884 --> 00:12:01,928
So could these
cosmic subway systems...
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00:12:02,638 --> 00:12:06,433
theoretically be engineered
into time machines?
198
00:12:09,395 --> 00:12:11,688
Einstein's general relativity laws...
199
00:12:11,731 --> 00:12:17,318
reveal that time travel
into the future is possible.
200
00:12:19,113 --> 00:12:22,407
They show that time
is perceived differently...
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depending on where one is
in the universe...
202
00:12:26,662 --> 00:12:28,538
and how one moves.
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00:12:30,249 --> 00:12:33,168
Objects moving at close
to the speed of light...
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00:12:33,210 --> 00:12:36,087
age slower than static objects...
205
00:12:38,466 --> 00:12:41,301
and objects
near a gravitating body...
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00:12:41,343 --> 00:12:45,513
age more slowly
than objects farther away.
207
00:12:47,266 --> 00:12:51,394
Clocks run at different rates
in different gravitational fields.
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The stronger the gravitational field,
the more slowly time passes...
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00:12:57,693 --> 00:13:02,363
relative to someone out in space
where there's no gravitational field.
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00:13:03,449 --> 00:13:05,492
On Earth here,
on the surface...
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00:13:05,534 --> 00:13:09,329
our clocks run
slightly more slowly...
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00:13:09,371 --> 00:13:12,290
than clocks high up in the sky.
213
00:13:12,875 --> 00:13:14,167
So an example of this...
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00:13:14,210 --> 00:13:18,171
is that the clocks in the GPS
system of satellites...
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00:13:18,214 --> 00:13:22,008
run a little bit more quickly
than the clocks here on Earth...
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because they're
in a weaker gravitational field.
217
00:13:24,470 --> 00:13:28,807
And the scientists and engineers
developing the GPS system...
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had to take into account
the different rate at which clocks run.
219
00:13:33,229 --> 00:13:37,982
If they hadn't done that correctly,
then your GPS system wouldn't work.
220
00:13:38,025 --> 00:13:41,027
If you were taking a trip
from Los Angeles to New York...
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you'd end up somewhere
in Massachusetts.
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00:13:48,160 --> 00:13:50,119
Forward time travel
has been tested...
223
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using highly precise
atomic clocks.
224
00:13:55,167 --> 00:13:58,253
Scientists have placed
one clock on the ground...
225
00:13:59,129 --> 00:14:02,423
and another in a rocket
flying high above the Earth.
226
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The two were compared...
227
00:14:05,761 --> 00:14:09,097
using radio signals
between rocket and ground.
228
00:14:10,766 --> 00:14:13,893
The clock
on the rocket ticked faster.
229
00:14:15,688 --> 00:14:18,565
Here on Earth,
my clock is running more slowly...
230
00:14:18,607 --> 00:14:20,191
compared to someone
in a rocket ship...
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00:14:20,234 --> 00:14:22,443
somewhere further away
from Earth.
232
00:14:22,486 --> 00:14:24,237
So their clock
is moving more quickly.
233
00:14:24,280 --> 00:14:26,281
They're going
to the future faster.
234
00:14:28,617 --> 00:14:31,411
Physicists have studied
whether wormholes...
235
00:14:31,453 --> 00:14:34,956
could provide travel,
not only to the future...
236
00:14:35,958 --> 00:14:37,959
but also to the past.
237
00:14:39,378 --> 00:14:42,630
If there was a wormhole
with one mouth near Earth...
238
00:14:44,049 --> 00:14:46,718
and the other
in the center of our galaxy...
239
00:14:47,970 --> 00:14:50,680
the rate of flow of time
will be different...
240
00:14:50,723 --> 00:14:53,433
at the one mouth
than at the other...
241
00:14:53,475 --> 00:14:56,144
when compared
through the external universe.
242
00:14:58,814 --> 00:15:01,649
But when looking directly
through the wormhole...
243
00:15:01,692 --> 00:15:05,153
the rate of flow of time
appears to be the same.
244
00:15:09,491 --> 00:15:12,452
This difference
in their relative ticking rates...
245
00:15:12,494 --> 00:15:16,289
as viewed externally versus
viewed through the wormhole...
246
00:15:16,332 --> 00:15:19,375
would convert the wormhole
into a time machine.
247
00:15:23,505 --> 00:15:26,674
What that means is that
by entering a wormhole...
248
00:15:27,676 --> 00:15:29,844
you could leave here today...
249
00:15:29,887 --> 00:15:32,639
and come out the other end
of the wormhole...
250
00:15:32,681 --> 00:15:35,600
hundreds or thousands
of years earlier.
251
00:15:38,020 --> 00:15:41,147
The wormhole
may lead to things...
252
00:15:41,190 --> 00:15:44,525
like being able
to go to another galaxy...
253
00:15:47,821 --> 00:15:49,864
or even going to another time.
254
00:15:51,659 --> 00:15:55,912
It's possible you can use
a wormhole of a certain kind...
255
00:15:55,955 --> 00:15:59,040
to actually transport
information backward in time...
256
00:15:59,083 --> 00:16:00,541
or people backward in time.
257
00:16:02,878 --> 00:16:06,714
But backward time travel
raises disturbing paradoxes.
258
00:16:07,883 --> 00:16:12,470
Could one actually voyage
to the past and change history?
259
00:16:18,310 --> 00:16:21,104
One of the problems
with traveling backwards in time...
260
00:16:21,146 --> 00:16:23,898
is that it produces
various paradoxes...
261
00:16:23,941 --> 00:16:26,192
the most famous of this
is the grandfather paradox.
262
00:16:26,235 --> 00:16:28,569
This says that
if I have a time machine...
263
00:16:28,612 --> 00:16:30,154
and I could go back in time...
264
00:16:30,197 --> 00:16:31,948
and I could kill my grandfather...
265
00:16:31,991 --> 00:16:35,034
who would then never
have had my father...
266
00:16:35,077 --> 00:16:36,077
who would never have had me...
267
00:16:36,120 --> 00:16:37,495
I would never have been born...
268
00:16:37,538 --> 00:16:38,871
so that means you would never
have been able...
269
00:16:38,914 --> 00:16:40,999
to go back into the past
in the first place.
270
00:16:42,584 --> 00:16:45,378
Or let's say
you go backwards in time...
271
00:16:45,421 --> 00:16:48,256
and meet your teenage mother
before you're born...
272
00:16:48,298 --> 00:16:51,676
and then your teenage mother
falls in love with you...
273
00:16:51,719 --> 00:16:53,553
then how can you be born...
274
00:16:53,595 --> 00:16:55,972
if your teenager mother
spurned your father...
275
00:16:56,015 --> 00:16:57,890
and fell in love with you instead?
276
00:16:57,933 --> 00:17:00,435
The practical problems
are enormous.
277
00:17:01,353 --> 00:17:04,022
But one day, if somebody
knocks on your door...
278
00:17:04,064 --> 00:17:06,232
and claims to be your
great-great-great-great...
279
00:17:06,275 --> 00:17:08,067
great-great-
great-granddaughter...
280
00:17:08,110 --> 00:17:10,778
someone from the future
going backwards in time...
281
00:17:10,821 --> 00:17:15,033
to meet her illustrious ancestor,
don't slam the door.
282
00:17:15,075 --> 00:17:17,827
Perhaps, in the future,
our descendants...
283
00:17:17,870 --> 00:17:20,413
will have the possibility
of time travel...
284
00:17:20,456 --> 00:17:23,708
and perhaps, one day, they may
come knocking on your door.
285
00:17:26,545 --> 00:17:31,591
Backward time travel has ignited
a myriad of science fiction scenarios.
286
00:17:32,676 --> 00:17:35,762
If that machine can do
what you say it can...
287
00:17:35,804 --> 00:17:38,181
destroy it, George,
before it destroys you.
288
00:17:40,434 --> 00:17:43,352
If the laws of physics
permit wormholes...
289
00:17:44,521 --> 00:17:48,524
then how can those laws deal
with the danger of changing history?
290
00:17:51,403 --> 00:17:54,655
One possibility is that
the laws of physics...
291
00:17:54,698 --> 00:17:57,283
allow you to do
backward time travel...
292
00:17:57,326 --> 00:18:00,912
as long as it leads to
a self-consistent universe...
293
00:18:00,954 --> 00:18:04,165
that, in some sense,
the history is not changeable.
294
00:18:04,208 --> 00:18:06,292
You can't go backwards
and change things...
295
00:18:06,335 --> 00:18:08,836
which would stop you from having
been created in the first place...
296
00:18:08,879 --> 00:18:10,671
for example,
in the grandfather paradox.
297
00:18:13,217 --> 00:18:15,635
For now, forward
or backward time travel...
298
00:18:15,677 --> 00:18:18,471
through a wormhole
remains in question.
299
00:18:18,514 --> 00:18:19,722
And some scientists think...
300
00:18:19,765 --> 00:18:22,767
that any attempt to create
a wormhole time machine...
301
00:18:22,810 --> 00:18:24,852
may destroy the wormhole.
302
00:18:27,397 --> 00:18:29,649
What actually happens when
you try and make that wormhole...
303
00:18:29,691 --> 00:18:30,942
into a time machine...
304
00:18:30,984 --> 00:18:33,319
is that as soon as it starts
connecting different times...
305
00:18:33,362 --> 00:18:35,613
you get a pile-up
of radiation so intense...
306
00:18:35,656 --> 00:18:38,658
that it destroys
the entire wormhole...
307
00:18:38,700 --> 00:18:40,576
thus stopping you
from making that wormhole...
308
00:18:40,619 --> 00:18:41,911
into a time machine.
309
00:18:41,954 --> 00:18:43,037
This seems to be a sign...
310
00:18:43,080 --> 00:18:46,666
that maybe this is the way
nature protects itself...
311
00:18:46,708 --> 00:18:47,834
using the laws of physics...
312
00:18:47,876 --> 00:18:50,670
from ever producing paradoxes
and strange things...
313
00:18:50,712 --> 00:18:52,713
that time machines
seem to suggest.
314
00:18:54,716 --> 00:18:57,176
Wormhole travel is really iffy...
315
00:18:57,219 --> 00:18:59,846
because you have to know
a lot about the wormhole...
316
00:18:59,888 --> 00:19:01,848
so that it doesn't do
unpleasant things...
317
00:19:01,890 --> 00:19:06,894
like, for example, turn you into
a big ball of gas all of a sudden...
318
00:19:06,937 --> 00:19:08,980
because
the gravitational stresses...
319
00:19:09,022 --> 00:19:14,944
that support the wormhole
are plausibly quite strong.
320
00:19:16,989 --> 00:19:18,990
The idea of a wormhole...
321
00:19:19,032 --> 00:19:21,033
is not something
that we can point to and say...
322
00:19:21,076 --> 00:19:22,076
"That's impossible. "
323
00:19:22,119 --> 00:19:26,247
It would be absurd to say,
"We can't do that ever"...
324
00:19:26,290 --> 00:19:31,002
because we're dealing with powers,
energies, and knowledge...
325
00:19:31,044 --> 00:19:34,255
that are outside
of our current domain.
326
00:19:37,384 --> 00:19:38,718
Like a wormhole...
327
00:19:38,760 --> 00:19:42,180
there's another phenomenon
that has never been discovered...
328
00:19:43,599 --> 00:19:48,102
but Einstein's general relativity laws
allow for its existence.
329
00:19:48,854 --> 00:19:51,397
It's called a white hole.
330
00:19:53,817 --> 00:19:55,484
Well, a black hole is an object...
331
00:19:55,527 --> 00:19:57,737
into which things are
falling and disappearing...
332
00:19:57,779 --> 00:19:59,572
rather like a sinkhole.
333
00:19:59,615 --> 00:20:01,115
A white hole
is doing the opposite.
334
00:20:01,158 --> 00:20:02,658
Things are coming out.
335
00:20:02,701 --> 00:20:04,827
Things are coming out
rather like a fountain.
336
00:20:06,413 --> 00:20:09,081
A white hole
is like the unicorn...
337
00:20:09,124 --> 00:20:12,043
an exotic animal
that's never been seen before.
338
00:20:12,085 --> 00:20:14,670
A white hole is very similar
to a black hole...
339
00:20:14,713 --> 00:20:16,547
except it runs backwards.
340
00:20:16,590 --> 00:20:19,091
Think of running
the videotape backwards.
341
00:20:19,134 --> 00:20:23,471
Instead of matter falling into
the event horizon never to come out...
342
00:20:23,513 --> 00:20:26,140
matter falls out of a black hole...
343
00:20:26,183 --> 00:20:29,602
so it's the opposite,
a time-reverse black hole.
344
00:20:31,313 --> 00:20:32,730
Black holes, as we know...
345
00:20:32,773 --> 00:20:37,151
have now been understood
to be out there in our universe.
346
00:20:37,194 --> 00:20:38,486
And so you might wonder...
347
00:20:38,528 --> 00:20:42,114
whether the same thing is true
about white holes as well.
348
00:20:42,157 --> 00:20:45,243
For example, quasars, when
they were first discovered...
349
00:20:45,285 --> 00:20:47,787
were thought to be
maybe white holes.
350
00:20:47,829 --> 00:20:50,081
Why? Because they seemed
to be producing...
351
00:20:50,123 --> 00:20:51,791
a huge amount of energy.
352
00:20:52,668 --> 00:20:54,877
We now know
that that's not the case.
353
00:20:54,920 --> 00:20:57,296
Quasars are actually
powered by black holes.
354
00:20:58,423 --> 00:21:01,634
There's a school of thought that says
that anything that can exist...
355
00:21:01,677 --> 00:21:03,219
must exist somewhere.
356
00:21:03,262 --> 00:21:05,346
And if one adopts
that school of thought...
357
00:21:05,389 --> 00:21:07,473
then at the moment,
we have to admit...
358
00:21:07,516 --> 00:21:09,809
that white holes might be
out there somewhere.
359
00:21:11,103 --> 00:21:14,730
If nature uses white holes,
physicists speculate...
360
00:21:14,773 --> 00:21:17,191
that they could have been
an important element...
361
00:21:17,234 --> 00:21:20,194
in the earliest stages
of the universe...
362
00:21:20,237 --> 00:21:24,198
maybe even in the formation
of the universe itself.
363
00:21:34,376 --> 00:21:37,837
When trying to decode some
of the mysteries of the universe...
364
00:21:37,879 --> 00:21:42,049
the answers may truly be
black and white.
365
00:21:43,260 --> 00:21:46,012
The universe began
with the Big Bang...
366
00:21:46,054 --> 00:21:49,223
an expanding fireball
of matter and energy...
367
00:21:50,434 --> 00:21:54,687
that started compressed
as a tiny, subatomic point...
368
00:21:54,730 --> 00:21:56,397
called a singularity.
369
00:21:57,691 --> 00:22:02,236
A singularity is a region where
gravity is immensely strong.
370
00:22:03,238 --> 00:22:07,950
The Big Bang singularity gave rise
to the entire universe...
371
00:22:07,993 --> 00:22:12,079
which includes space, time,
and all the matter that fills it.
372
00:22:16,418 --> 00:22:19,754
A similar type of singularity
is a white hole...
373
00:22:20,672 --> 00:22:25,259
a theoretical object that arises
in Einstein's theory of gravity.
374
00:22:26,845 --> 00:22:29,889
It's essentially a black hole
in reverse...
375
00:22:31,224 --> 00:22:34,852
a point of singularity
where matter is ejected.
376
00:22:36,063 --> 00:22:39,231
Consequently,
some scientists have wondered...
377
00:22:39,274 --> 00:22:43,861
if the universe could have been
created from a white hole.
378
00:22:45,781 --> 00:22:48,741
One idea to describe
the entire universe...
379
00:22:48,784 --> 00:22:50,743
has been that it's
one big white hole...
380
00:22:50,786 --> 00:22:54,955
in which there's an emergence
from some initial singularity.
381
00:22:54,998 --> 00:22:57,416
That creative thought
is one amongst many...
382
00:22:57,459 --> 00:23:00,002
for how the universe
was seeded...
383
00:23:00,045 --> 00:23:02,380
and how it began
and how the Big Bang emerged.
384
00:23:03,673 --> 00:23:06,342
Think about it,
a white hole emits matter...
385
00:23:06,385 --> 00:23:07,843
it doesn't gobble up matter.
386
00:23:07,886 --> 00:23:10,262
But isn't the Big Bang
that same thing...
387
00:23:10,305 --> 00:23:15,184
that small, little quantum dot
that expands and spews out matter?
388
00:23:15,227 --> 00:23:18,979
So perhaps the white hole
could be the story of our universe.
389
00:23:22,567 --> 00:23:28,280
NASA's Wilkinson Microwave
Anisotropy Probe, known as WMAP...
390
00:23:28,323 --> 00:23:32,952
has measured the radiation left over
from the very early universe.
391
00:23:34,788 --> 00:23:37,957
Studies of this
cosmic microwave background...
392
00:23:37,999 --> 00:23:40,334
have confirmed
that the universe began...
393
00:23:40,377 --> 00:23:44,672
with a brief, but colossal
growth birth, called inflation...
394
00:23:44,714 --> 00:23:47,633
that preceded its
regular phase of expansion.
395
00:23:49,803 --> 00:23:53,848
So some scientists speculate
whether a white hole...
396
00:23:53,890 --> 00:23:57,309
could have been the instigator
of this growth birth.
397
00:23:59,187 --> 00:24:02,189
The evidence coming
from our space satellites...
398
00:24:02,232 --> 00:24:05,151
like the WMAP,
orbiting the Earth right now...
399
00:24:05,193 --> 00:24:08,487
is consistent
with the idea of a multiverse.
400
00:24:08,530 --> 00:24:10,990
A multiverse
consists of many universes...
401
00:24:11,032 --> 00:24:14,618
like soap bubbles
floating in a bubble bath.
402
00:24:14,661 --> 00:24:17,997
In a bubble bath, we have bubbles
popping into existence...
403
00:24:18,039 --> 00:24:21,625
collapsing back, giving birth
to baby soap bubbles.
404
00:24:21,668 --> 00:24:26,005
So in other words, Big Bangs
could be happening all the time.
405
00:24:26,047 --> 00:24:29,341
Perhaps each Big Bang
starts with a white hole...
406
00:24:29,384 --> 00:24:33,637
that then expands rapidly,
giving us a baby universe.
407
00:24:37,392 --> 00:24:41,145
It's still unproven
whether multiple universes exist...
408
00:24:42,147 --> 00:24:45,274
and whether white holes
may have created them...
409
00:24:47,235 --> 00:24:50,404
but scientists have shown
that some types of white holes...
410
00:24:50,447 --> 00:24:53,782
although possible in theory,
are highly unstable.
411
00:24:54,868 --> 00:24:57,036
They would not survive
for very long...
412
00:24:57,078 --> 00:25:00,706
and they simply collapse
to form black holes.
413
00:25:02,584 --> 00:25:04,543
Possibly white holes
played a role.
414
00:25:04,586 --> 00:25:07,421
Perhaps they formed
for a very short time...
415
00:25:07,464 --> 00:25:09,298
but then, being unstable...
they collapsed.
416
00:25:09,341 --> 00:25:12,885
But even during that period
when they were first formed...
417
00:25:12,928 --> 00:25:15,221
they may have left
some important imprint...
418
00:25:15,263 --> 00:25:17,056
on the future of the universe.
419
00:25:17,098 --> 00:25:18,682
We don't know
whether that's true...
420
00:25:18,725 --> 00:25:20,434
but it's a possibility.
421
00:25:20,477 --> 00:25:23,437
White holes are
a nice active imagination...
422
00:25:23,480 --> 00:25:26,774
but I don't think
they have any substance yet.
423
00:25:26,816 --> 00:25:29,235
They're entirely
theoretical objects.
424
00:25:29,277 --> 00:25:31,987
But then black holes were
that way once upon a time.
425
00:25:34,449 --> 00:25:36,617
White holes might
or might not have existed...
426
00:25:36,660 --> 00:25:38,661
at the beginning
of the universe...
427
00:25:38,703 --> 00:25:40,746
but one thing's certain...
428
00:25:40,789 --> 00:25:43,958
black holes are
no longer science fiction.
429
00:25:44,000 --> 00:25:46,001
They're science fact.
430
00:25:50,131 --> 00:25:53,175
Scientists agree
these whirling vortexes...
431
00:25:53,218 --> 00:25:56,887
are born out of the death throes
of massive stars.
432
00:25:59,140 --> 00:26:02,601
When a sufficiently massive star
runs out of fuel...
433
00:26:02,644 --> 00:26:07,481
it is unable to support itself
against its own gravitational pull.
434
00:26:08,525 --> 00:26:12,486
It then collapses inward
to form a black hole.
435
00:26:14,322 --> 00:26:18,993
Black holes are troublemakers
in the evolution of the universe.
436
00:26:19,035 --> 00:26:23,539
They can draw matter in,
spew it out...
437
00:26:23,582 --> 00:26:26,875
re-form, reorganize
regions of the universe...
438
00:26:26,918 --> 00:26:28,919
perhaps part of a galaxy...
439
00:26:28,962 --> 00:26:31,839
take up residence at the center,
start running the show.
440
00:26:31,881 --> 00:26:33,048
They're big, muscular things...
441
00:26:33,091 --> 00:26:35,426
that lumber around
and cannot be stopped.
442
00:26:38,054 --> 00:26:41,765
Black holes are difficult to detect
because they're black.
443
00:26:43,518 --> 00:26:45,144
But they can be observed...
444
00:26:45,186 --> 00:26:47,813
when they interact
with something in space...
445
00:26:47,856 --> 00:26:49,898
such as infalling gas...
446
00:26:49,941 --> 00:26:52,818
which heats up
and glows in X-rays.
447
00:26:55,322 --> 00:26:59,199
Years ago, black holes were
considered to be impossible.
448
00:26:59,242 --> 00:27:01,619
We have something called
the giggle factor in physics.
449
00:27:01,661 --> 00:27:04,538
People used to giggle whenever
we talked about black holes.
450
00:27:04,581 --> 00:27:07,583
But now we see
hundreds, thousands...
451
00:27:07,626 --> 00:27:10,294
of glorious photographs
of black holes.
452
00:27:14,049 --> 00:27:17,217
There are at least
two types of black holes.
453
00:27:17,260 --> 00:27:20,679
One is called
a stellar mass black hole...
454
00:27:20,722 --> 00:27:23,641
which is approximately
three to thirty times...
455
00:27:23,683 --> 00:27:25,601
the mass of our sun.
456
00:27:25,644 --> 00:27:28,687
It's speculated
that 100 million of these...
457
00:27:28,730 --> 00:27:33,859
reside in our Milky Way galaxy
and similar numbers in other galaxies.
458
00:27:35,904 --> 00:27:38,530
The other is
a supermassive black hole...
459
00:27:38,573 --> 00:27:42,576
that is millions to billions of times
the mass of our sun.
460
00:27:48,249 --> 00:27:50,626
It's believed
that this humongous monster...
461
00:27:50,669 --> 00:27:53,671
lives at the center
of most every large galaxy.
462
00:27:56,216 --> 00:27:58,550
Our own Milky Way galaxy has one.
463
00:28:00,595 --> 00:28:04,264
Yet, whether they're
stellar mass size or supermassive...
464
00:28:04,307 --> 00:28:07,476
all black holes
are cosmic cannibals.
465
00:28:10,105 --> 00:28:13,941
A black hole, in some sense,
is like a cosmic roach motel.
466
00:28:13,983 --> 00:28:17,277
Everything checks in,
but nothing checks out.
467
00:28:18,655 --> 00:28:21,448
A trip to a black hole
would be fantastic...
468
00:28:21,491 --> 00:28:23,158
almost psychedelic.
469
00:28:23,201 --> 00:28:26,328
It's like having
a near-death experience.
470
00:28:26,371 --> 00:28:29,331
As you get even closer
to the black hole...
471
00:28:29,374 --> 00:28:32,876
tidal forces begin to stretch
your body apart...
472
00:28:32,919 --> 00:28:35,754
so that the top of your body
and the bottom of your body...
473
00:28:35,797 --> 00:28:38,006
experience different
gravitational forces...
474
00:28:38,049 --> 00:28:40,384
and you become spaghettified.
475
00:28:40,427 --> 00:28:43,095
Eventually,
even the atoms of your body...
476
00:28:43,138 --> 00:28:45,764
become noodles
and become ripped apart.
477
00:28:47,392 --> 00:28:50,060
In the case
of a supermassive black hole...
478
00:28:50,103 --> 00:28:52,438
the process of spaghettification
is somewhat different.
479
00:28:53,481 --> 00:28:57,109
The person jumping in
wouldn't be spaghettified...
480
00:28:57,152 --> 00:28:59,361
until passing
through the event horizon...
481
00:28:59,404 --> 00:29:02,281
and the reason for that
is because the tidal forces...
482
00:29:02,323 --> 00:29:05,367
that would stretch him
aren't strong enough...
483
00:29:05,410 --> 00:29:08,704
until you get closer
to the singularity.
484
00:29:08,747 --> 00:29:09,997
So the person jumping in...
485
00:29:10,039 --> 00:29:12,458
would have a few moments
of perception...
486
00:29:12,500 --> 00:29:14,084
that they were
inside of a black hole...
487
00:29:14,127 --> 00:29:15,419
and they could marvel
at that idea...
488
00:29:15,462 --> 00:29:17,963
before they plunged
toward the singularity...
489
00:29:18,006 --> 00:29:19,798
and then became spaghettified.
490
00:29:22,552 --> 00:29:25,637
And if one black hole
isn't violent enough...
491
00:29:25,680 --> 00:29:29,308
try two black holes
dueling for dominance.
492
00:29:43,031 --> 00:29:48,994
In the vastness of space,
black holes occasionally pair off.
493
00:29:49,037 --> 00:29:51,371
It may appear
as though they're engaging...
494
00:29:51,414 --> 00:29:54,208
in some sort
of cosmic courtship...
495
00:29:55,043 --> 00:29:58,837
but these unions are
anything but harmonious.
496
00:30:00,632 --> 00:30:03,091
When two black holes
get too close...
497
00:30:03,134 --> 00:30:06,386
they become trapped
by each other's gravity.
498
00:30:06,429 --> 00:30:10,474
The two orbit around each other
like whirling dervishes.
499
00:30:12,060 --> 00:30:17,105
These binary black holes
will eventually collide and coalesce.
500
00:30:19,526 --> 00:30:21,860
It's believed that collisions
between black holes...
501
00:30:21,903 --> 00:30:23,737
would be quite common.
502
00:30:23,780 --> 00:30:24,947
They would be in orbit
around each other...
503
00:30:24,989 --> 00:30:26,615
and then spiral inwards...
504
00:30:26,658 --> 00:30:29,368
and at some point
they would coalesce...
505
00:30:29,410 --> 00:30:34,414
and that coalescence creates
a huge disturbance in space-time.
506
00:30:35,416 --> 00:30:36,708
If you have two objects...
507
00:30:36,751 --> 00:30:39,545
that are bending space
a lot around them...
508
00:30:39,587 --> 00:30:41,004
and they merge together...
509
00:30:41,047 --> 00:30:44,633
then you'll get this ripple,
this wave going out...
510
00:30:44,676 --> 00:30:46,760
carrying energy with it.
511
00:30:51,432 --> 00:30:54,685
Typically,
when black holes collide...
512
00:30:54,727 --> 00:30:58,772
they create wild vibrations
called gravitational waves...
513
00:30:59,774 --> 00:31:03,235
which spread across the fabric
of space and time.
514
00:31:05,989 --> 00:31:07,614
These ripples will be
just like the ripples...
515
00:31:07,657 --> 00:31:09,658
you would have, say,
on the surface of a pond.
516
00:31:09,701 --> 00:31:13,203
If you threw a pebble into a pond,
it creates a disturbance...
517
00:31:13,246 --> 00:31:17,082
and then you see the ripples
carrying that disturbance...
518
00:31:17,125 --> 00:31:19,459
away to far points of the pond.
519
00:31:21,546 --> 00:31:24,339
In the past,
binary black hole collisions...
520
00:31:24,382 --> 00:31:26,592
were impossible to identify.
521
00:31:26,634 --> 00:31:31,388
Now scientists have developed
gravitational wave detectors...
522
00:31:31,431 --> 00:31:33,098
to track these vibrations...
523
00:31:33,141 --> 00:31:36,685
and hopefully catch
black hole collisions in the act.
524
00:31:42,483 --> 00:31:44,693
LIGO is
a ground-based observatory...
525
00:31:44,736 --> 00:31:45,903
that's currently searching...
526
00:31:45,945 --> 00:31:48,780
for gravity waves
produced from collisions...
527
00:31:48,823 --> 00:31:51,950
involving stellar-sized black holes...
528
00:31:51,993 --> 00:31:54,286
a few times
the mass of our Sun.
529
00:31:55,455 --> 00:31:59,458
The system uses lasers
to measure the motions of mirrors...
530
00:31:59,500 --> 00:32:02,502
that hang by wires
from overhead supports.
531
00:32:05,089 --> 00:32:06,882
When two black holes
merge together...
532
00:32:06,925 --> 00:32:09,718
they'll release
these gravitational waves...
533
00:32:09,761 --> 00:32:12,846
these ripples
in the shape of space.
534
00:32:12,889 --> 00:32:18,018
And as the ripples pass by
these giant contraptions...
535
00:32:18,061 --> 00:32:20,479
they alter ever so slightly...
536
00:32:20,521 --> 00:32:23,482
the distances
between these detectors...
537
00:32:23,524 --> 00:32:26,777
and the detectors
can actually monitor...
538
00:32:26,819 --> 00:32:29,821
and see that change
in distance...
539
00:32:29,864 --> 00:32:33,200
and that's the signature of
a gravitational wave coming by.
540
00:32:35,244 --> 00:32:36,995
In the future, LISA...
541
00:32:37,038 --> 00:32:40,332
a joint NASA and European
Space Agency mission...
542
00:32:40,375 --> 00:32:42,668
will be able to detect waves
from collisions...
543
00:32:42,710 --> 00:32:45,128
involving
supermassive black holes.
544
00:32:48,383 --> 00:32:52,511
These impacts occur
after two galaxies have merged...
545
00:32:52,553 --> 00:32:54,930
and their supermassive
black holes...
546
00:32:54,973 --> 00:32:58,475
sink to the center
of the newly formed galaxy...
547
00:32:58,518 --> 00:32:59,893
and find each other.
548
00:33:03,982 --> 00:33:07,401
And if collisions involving
two supermassive black holes...
549
00:33:07,443 --> 00:33:10,612
isn't chaotic enough, try three.
550
00:33:12,907 --> 00:33:17,327
In January 2007,
U.S. and European satellites...
551
00:33:17,370 --> 00:33:20,414
actually observed
black hole triplets...
552
00:33:20,456 --> 00:33:25,127
ten billion light-years away
in the Virgo constellation.
553
00:33:26,921 --> 00:33:31,174
They're actually three quasars,
which are luminous objects...
554
00:33:31,217 --> 00:33:34,428
thought to be powered
by supermassive black holes...
555
00:33:34,470 --> 00:33:36,763
located in the centers
of galaxies.
556
00:33:39,267 --> 00:33:42,602
This trio is in close proximity
to one another.
557
00:33:42,645 --> 00:33:47,691
They're only about 100,000
to 150,000 light-years apart...
558
00:33:47,734 --> 00:33:50,736
which is about the width
of our Milky Way.
559
00:33:53,114 --> 00:33:58,660
In all probability the three will
eventually engage in a hostile merger.
560
00:34:01,581 --> 00:34:05,292
If you take three large black holes,
brought close together...
561
00:34:05,334 --> 00:34:08,462
because two big spiral
or elliptical galaxies...
562
00:34:08,504 --> 00:34:11,631
have slammed together,
then it's a real free-for-all.
563
00:34:11,674 --> 00:34:14,217
And two of them
could win the game...
564
00:34:14,260 --> 00:34:15,594
and throw the third one out.
565
00:34:17,805 --> 00:34:20,640
Gravitational interactions
between three bodies...
566
00:34:20,683 --> 00:34:22,809
can lead to the ejection...
567
00:34:22,852 --> 00:34:26,146
of one of the supermassive
black holes from the system...
568
00:34:26,189 --> 00:34:30,400
and then you're just left
with a binary supermassive pair...
569
00:34:30,443 --> 00:34:32,819
that will coalesce ultimately.
570
00:34:34,739 --> 00:34:37,365
The supermassive black hole
that gets ejected...
571
00:34:37,408 --> 00:34:40,535
is ejected typically
with enough speed...
572
00:34:40,578 --> 00:34:46,249
that it can't carry stars with it,
so it becomes a rogue black hole.
573
00:34:46,292 --> 00:34:48,085
It's off on its own.
574
00:34:51,464 --> 00:34:54,591
Modern science continues
to unravel the mysteries...
575
00:34:54,634 --> 00:34:56,635
surrounding black holes...
576
00:34:56,677 --> 00:35:00,680
but for some,
one enduring question remains.
577
00:35:03,142 --> 00:35:06,645
The deepest question
in all the black hole physics is...
578
00:35:06,687 --> 00:35:09,981
what lies on the other side
of a black hole?
579
00:35:10,024 --> 00:35:12,400
What happens if you
throw the encyclopedia...
580
00:35:12,443 --> 00:35:13,443
into a black hole?
581
00:35:13,486 --> 00:35:15,320
Is all that information lost?
582
00:35:15,363 --> 00:35:17,155
We don't know for sure.
583
00:35:18,825 --> 00:35:22,077
According to Einstein's
general relativity laws...
584
00:35:22,120 --> 00:35:25,122
nothing can ever come out
of a black hole.
585
00:35:26,415 --> 00:35:31,128
But if a black hole is extremely tiny,
the laws of quantum mechanics...
586
00:35:31,170 --> 00:35:34,214
merge with the laws
of general relativity.
587
00:35:36,926 --> 00:35:41,054
Quantum mechanics governs
the world of the very small...
588
00:35:41,097 --> 00:35:45,225
such as electrons, neutrons,
and other subatomic particles.
589
00:35:46,352 --> 00:35:50,313
General relativity
rules the world of the very large...
590
00:35:50,356 --> 00:35:55,277
where ordinary gravity is dominant
like planets, stars, and galaxies.
591
00:35:57,405 --> 00:35:58,780
The fact is,
when you put together...
592
00:35:58,823 --> 00:36:00,031
quantum theory
with black holes...
593
00:36:00,074 --> 00:36:04,661
you find that they aren't
completely inert objects...
594
00:36:04,704 --> 00:36:07,247
that only suck things in
and nothing comes out.
595
00:36:07,290 --> 00:36:08,623
They actually radiate.
596
00:36:10,585 --> 00:36:14,713
The black holes that radiate
are called mini black holes...
597
00:36:14,755 --> 00:36:17,382
which are much smaller
than their stellar mass...
598
00:36:17,425 --> 00:36:20,260
or supermassive
black hole cousins.
599
00:36:24,015 --> 00:36:27,225
Celebrated physicist
Stephen Hawking proposed...
600
00:36:27,268 --> 00:36:31,897
that if mini black holes exist,
they must emit radiation...
601
00:36:31,939 --> 00:36:35,066
which has been named
Hawking radiation.
602
00:36:35,109 --> 00:36:37,152
It is believed this radiation...
603
00:36:37,195 --> 00:36:40,238
will cause a tiny black hole
to evaporate...
604
00:36:40,281 --> 00:36:42,532
and potentially disappear.
605
00:36:45,453 --> 00:36:47,787
Hawking gave
mathematical evidence...
606
00:36:47,830 --> 00:36:52,000
that when a tiny black hole
forms and then evaporates...
607
00:36:52,043 --> 00:36:54,836
some of the information
that went into the black hole...
608
00:36:54,879 --> 00:36:56,838
never comes back out.
609
00:36:58,132 --> 00:37:02,761
This startling prediction caused
a firestorm among physicists...
610
00:37:02,803 --> 00:37:04,679
because the laws
of quantum theory...
611
00:37:04,722 --> 00:37:08,767
insist that information can
never be completely destroyed.
612
00:37:10,186 --> 00:37:12,062
Essentially,
the world split into two camps:
613
00:37:12,104 --> 00:37:15,649
Those who believed that
Hawking's calculation was really it...
614
00:37:15,691 --> 00:37:17,025
and the other camp that said...
615
00:37:17,068 --> 00:37:20,362
well, Hawking's calculation
needs refining.
616
00:37:20,404 --> 00:37:23,782
String theory and other theories
seem to suggest...
617
00:37:23,824 --> 00:37:25,784
that the information
is actually preserved.
618
00:37:25,826 --> 00:37:28,119
It just comes out very subtly.
619
00:37:29,205 --> 00:37:32,415
The question of what happens
to the information...
620
00:37:32,458 --> 00:37:37,671
that goes inside a black hole is,
I think, not fully settled.
621
00:37:37,713 --> 00:37:40,257
The chemical composition
of the objects...
622
00:37:40,299 --> 00:37:43,635
that went into the black hole
and other aspects of them-
623
00:37:43,678 --> 00:37:46,763
their color, their temperature,
et cetera, et cetera-
624
00:37:46,806 --> 00:37:49,933
we don't really know what
happens to that information.
625
00:37:54,563 --> 00:37:56,773
It appears
unlikely that scientists...
626
00:37:56,816 --> 00:37:59,317
could venture
inside any black hole...
627
00:37:59,360 --> 00:38:03,029
and return back home in one piece
to report their findings.
628
00:38:06,075 --> 00:38:08,994
But a worldwide collaboration
of scientists...
629
00:38:09,036 --> 00:38:12,122
may be on the verge
of the next best thing:
630
00:38:12,164 --> 00:38:16,376
Manufacturing tiny black holes
right here on Earth.
631
00:38:27,096 --> 00:38:32,142
Today, scientists are pushing back
the boundaries of cosmic research.
632
00:38:34,729 --> 00:38:38,356
If naturally formed black holes
aren't scary enough...
633
00:38:38,399 --> 00:38:41,234
what about a black hole factory?
634
00:38:45,448 --> 00:38:49,993
In Switzerland, at the physics
laboratory called CERN...
635
00:38:50,036 --> 00:38:54,122
scientists have built
the Large Hadron Collider...
636
00:38:54,165 --> 00:38:59,586
the biggest, most complex
science experiment ever constructed.
637
00:39:00,629 --> 00:39:04,591
It's a particle accelerator
seventeen miles long...
638
00:39:04,633 --> 00:39:07,344
and the weight of five jumbo jets.
639
00:39:07,386 --> 00:39:11,389
It's capable of crushing
subatomic particles together...
640
00:39:11,432 --> 00:39:12,849
to replicate the energies...
641
00:39:12,892 --> 00:39:16,436
that existed microseconds
after the Big Bang.
642
00:39:18,481 --> 00:39:21,191
This particle collider
was designed and built...
643
00:39:21,233 --> 00:39:25,236
to study important questions
in fundamental particle physics...
644
00:39:26,447 --> 00:39:29,741
but it will cram
so much energy together...
645
00:39:29,784 --> 00:39:31,618
that, if physicists are lucky...
646
00:39:31,660 --> 00:39:33,995
about how nature works
at those energies...
647
00:39:34,038 --> 00:39:37,415
it could also produce
tiny black holes.
648
00:39:38,918 --> 00:39:41,669
We might be able to see
microscopic black holes...
649
00:39:41,712 --> 00:39:44,756
being formed
in these high energy collisions...
650
00:39:44,799 --> 00:39:49,010
and those black holes
would then be amenable to study.
651
00:39:49,053 --> 00:39:50,929
They would rapidly evaporate.
652
00:39:50,971 --> 00:39:53,098
We'd be able to study
their decay products...
653
00:39:53,140 --> 00:39:56,601
and understand physics
of quantum gravity in the laboratory...
654
00:39:56,644 --> 00:39:58,103
which is something
that we never dreamed...
655
00:39:58,145 --> 00:40:00,230
we'd be able to do
in our lifetimes.
656
00:40:02,817 --> 00:40:06,111
But the possibility of
manufacturing mini black holes...
657
00:40:06,153 --> 00:40:09,114
has roused
suspicion and fear.
658
00:40:09,156 --> 00:40:11,574
Could they escape
the Earth's gravity...
659
00:40:11,617 --> 00:40:14,327
and eventually
devour our planet?
660
00:40:16,497 --> 00:40:19,791
Cosmic rays from outer space
hit the Earth all the time...
661
00:40:19,834 --> 00:40:23,461
perhaps with more energy
than these mini black holes.
662
00:40:23,504 --> 00:40:25,797
So these mini black holes
are harmless.
663
00:40:25,840 --> 00:40:27,132
They're not going to
eat up the Earth.
664
00:40:27,174 --> 00:40:28,883
They are not
a doomsday device.
665
00:40:31,011 --> 00:40:34,973
A similar mini black hole scare
happened in the United States.
666
00:40:36,183 --> 00:40:37,809
In Brookhaven, New York...
667
00:40:37,852 --> 00:40:41,646
a smaller collider experiment
is already under way.
668
00:40:43,232 --> 00:40:47,235
The Relativistic Heavy lon Collider,
better known as RHIC...
669
00:40:47,278 --> 00:40:52,615
is an underground pipeline
where gold atoms collide together...
670
00:40:52,658 --> 00:40:56,035
at 99.9 percent
the speed of light.
671
00:41:00,749 --> 00:41:03,751
When the experiment began
in the year 2000...
672
00:41:03,794 --> 00:41:08,381
news spread that these head-on
impacts created black holes.
673
00:41:10,634 --> 00:41:12,510
The laboratory,
which is very responsible...
674
00:41:12,553 --> 00:41:15,597
decided it needed to respond
to this and reassure people.
675
00:41:15,639 --> 00:41:18,975
So it convened a group
to look at this...
676
00:41:19,018 --> 00:41:22,520
and what that group found
was that these kinds of collisions...
677
00:41:22,563 --> 00:41:24,189
had been happening
in outer space...
678
00:41:24,231 --> 00:41:26,649
and that had never caused
a problem.
679
00:41:26,692 --> 00:41:29,986
Theoretically, we produce conditions
in these collisions...
680
00:41:30,029 --> 00:41:32,822
which should mathematically
give some similarity...
681
00:41:32,865 --> 00:41:35,074
to the theory
that surrounds black holes.
682
00:41:35,117 --> 00:41:37,577
But in practice,
we're completely safe.
683
00:41:37,620 --> 00:41:41,039
There's no way that any black hole
that could be a concern...
684
00:41:41,081 --> 00:41:43,333
could be produced here at RHIC.
685
00:41:45,002 --> 00:41:47,337
Well, RHIC certainly is not capable...
686
00:41:47,379 --> 00:41:50,673
of producing a black hole
of any kind.
687
00:41:50,716 --> 00:41:53,885
There is not enough mass
which is being created here...
688
00:41:53,928 --> 00:41:56,387
by many orders of magnitude.
689
00:41:57,765 --> 00:42:01,643
Although RHIC cannot create
mini black holes...
690
00:42:01,685 --> 00:42:05,813
scientists can go through the ashes
of these particle collisions...
691
00:42:05,856 --> 00:42:08,149
to learn about
the early moments...
692
00:42:08,192 --> 00:42:11,486
a few microseconds
after the Big Bang.
693
00:42:12,655 --> 00:42:17,534
So we can use this knowledge
to gain a better understanding...
694
00:42:17,576 --> 00:42:20,245
of what happened shortly
after the Big Bang...
695
00:42:20,287 --> 00:42:25,667
including the possibility
of primordial black hole formation.
696
00:42:30,297 --> 00:42:34,926
The particle collision experiments
in Switzerland and in the U.S...
697
00:42:34,969 --> 00:42:37,428
may not produce
life-threatening black holes...
698
00:42:39,306 --> 00:42:42,600
but they could give
several important clues...
699
00:42:42,643 --> 00:42:45,395
about whether information
comes back out...
700
00:42:45,437 --> 00:42:49,983
of the mini black hole
and even how the universe began.
701
00:42:52,069 --> 00:42:54,487
They do provide a laboratory...
702
00:42:54,530 --> 00:42:57,532
to see how far we can push
Einstein's theory...
703
00:42:57,575 --> 00:43:02,036
until all hell breaks loose
and the equations collapse.
704
00:43:02,079 --> 00:43:04,455
And that's why we think
that mini black holes...
705
00:43:04,498 --> 00:43:08,543
could be a key
to going beyond Einstein.
706
00:43:12,214 --> 00:43:15,425
Physicists will continue
to probe into the mysteries...
707
00:43:15,467 --> 00:43:18,136
still surrounding black holes.
708
00:43:18,178 --> 00:43:20,221
They will also remain
on high alert...
709
00:43:20,264 --> 00:43:24,601
for any signs of the elusive
wormholes and white holes.
710
00:43:27,021 --> 00:43:30,356
The search for the next frontier
marches on.
711
00:43:32,109 --> 00:43:33,985
White holes, wormholes,
black holes...
712
00:43:34,028 --> 00:43:36,988
are tickets to oblivion
for the most part.
713
00:43:37,031 --> 00:43:38,031
None of these are places...
714
00:43:38,073 --> 00:43:41,492
that you want to take
your summer vacation near...
715
00:43:41,535 --> 00:43:45,747
and these tickets will cost
a lot to even find.
716
00:43:45,789 --> 00:43:49,083
These objects are hard
to observe in the universe...
717
00:43:49,126 --> 00:43:53,796
and only one of them do we
really pretty much know is there...
718
00:43:53,839 --> 00:43:55,173
the black hole.
719
00:43:55,215 --> 00:43:57,634
The others may be
entirely hypothetical.
720
00:43:57,676 --> 00:44:00,011
They may be the unicorns
of astronomy.
721
00:44:01,722 --> 00:44:03,973
There are several cases
in the history of science...
722
00:44:04,016 --> 00:44:07,518
when an idea or even
a solution to an equation...
723
00:44:07,561 --> 00:44:10,438
just seemed like an artifact
of our imaginations...
724
00:44:10,481 --> 00:44:13,524
and actually turned out
to be a real thing.
725
00:44:13,567 --> 00:44:15,234
Black holes are
such an example.
726
00:44:15,277 --> 00:44:18,946
Maybe white holes and wormholes
will have some role in nature...
727
00:44:18,989 --> 00:44:20,615
which we'll one day discover.
62043
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