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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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00:00:09,467 --> 00:00:12,219
of time, space, and matter.
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00:00:12,262 --> 00:00:14,805
Now, see further
than we've ever imagined...
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00:00:14,848 --> 00:00:16,807
beyond the limits
of our existence...
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00:00:16,850 --> 00:00:19,351
in a place we call
"The Universe. "
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00:00:22,605 --> 00:00:24,982
Does our Sun have
a deadly nemesis...
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that dooms life
on our planet?
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00:00:32,490 --> 00:00:35,826
Is it possible to travel
through time?
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It is one
of the greatest questions.
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00:00:40,248 --> 00:00:44,251
What happened to matter's
evil twin?
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The mind hunts
for an explanation.
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How did the water on Mars
disappear?
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00:00:53,428 --> 00:00:57,765
And what came
before the Big Bang?
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00:00:57,807 --> 00:01:03,687
This is the greatest mystery
in all of science.
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00:01:03,730 --> 00:01:06,690
Big questions,
and cutting-edge science.
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00:01:06,733 --> 00:01:11,153
"The Universe:
Unexplained Mysteries. "
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Among the unexplained
mysteries in the universe...
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one has a particular urgency...
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for those of us who enjoy
living on planet Earth.
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Do Earthlings have...
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a regularly scheduled date
with extinction...
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once every 26 million years?
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And if so, what causes...
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this periodic hard rain
of destruction?
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You have this
enormous explosion.
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Anything within thousands
of miles will be killed.
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You're talking here...
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first of the blast wave
of the tsunami.
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You're talking
about the enormous heat.
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Fires all around the globe...
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and then darkness.
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For millions of years...
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enormous objects from space
have slammed into Earth...
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with disastrous results.
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One impact in the waters
off the Yucatan Peninsula...
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is blamed for the extinction
of the dinosaurs...
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65 million years ago.
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But this wasn't the first
mass extinction on Earth...
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and it probably
won't be the last.
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And it wasn't the biggest mass
extinction event of all time...
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because that one
was the Permean Extinction...
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in which 95 percent...
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of the species
in the oceans died...
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and about 80 percent
of those on land.
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So radical extinction events
have happened.
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Some scientists believe...
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these periods
of death and destruction...
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happen like clockwork.
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Some paleontologists found
a very strange pattern.
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What they found were
the great extinctions...
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such as ones
that killed the dinosaurs...
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but others, too, didn't
happen at random times...
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but seemed to occur
on a regular time schedule.
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That was very strange.
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They were disappearing
every 26 million years.
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It was begging
for an explanation.
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Astrophysicist Richard Muller
believes...
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the explanation
for this periodic destruction...
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is a dim red dwarf star...
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lurking on the edge
of the solar system...
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a star that he fittingly
calls Nemesis.
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According to his theory...
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Nemesis is an undiscovered
companion star to our own Sun.
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It travels between one
and three light-years...
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from the center
of the solar system...
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on an elongated
elliptical orbit.
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As Nemesis makes its
closest approach to the Sun...
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every 26 million years...
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its orbit takes it
right through the Oort Cloud...
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a collection of an estimated
trillion comets...
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surrounding our solar system.
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That's when the order
of the solar system...
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turns especially chaotic.
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When that happens...
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Nemesis gets close
to the comets...
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and perturbs their orbit.
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00:05:03,469 --> 00:05:06,722
According to Muller's theory,
the gravitational disruption...
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00:05:06,764 --> 00:05:09,349
caused by this
small innocuous star...
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causes long-undisturbed
comets...
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to break away from their
orbits in the Oort Cloud.
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Pulled towards the Sun
by its gravity...
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a billion comets
are sent careening...
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toward the inner solar system.
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A handful inevitably
cross paths with the Earth...
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resulting in massive impacts
and mass extinctions.
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The claim that our Sun...
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00:05:43,009 --> 00:05:45,761
has an undiscovered
companion death star...
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00:05:45,803 --> 00:05:47,304
is controversial.
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00:05:53,144 --> 00:05:55,020
Most scientists believe
that the Sun...
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00:05:55,063 --> 00:06:02,069
is a solitary star
with no companions.
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00:06:02,111 --> 00:06:03,403
But in the universe...
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00:06:03,446 --> 00:06:06,907
binary or even triplet stars
grouped together by gravity...
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00:06:06,949 --> 00:06:08,575
are the norm.
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00:06:15,583 --> 00:06:17,751
The majority of stars
in our galaxy...
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00:06:17,794 --> 00:06:21,254
are parts of either
binary or triple stars...
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00:06:21,297 --> 00:06:23,632
and so the idea that the Sun...
99
00:06:23,674 --> 00:06:25,759
conceivably could be
part of a binary...
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isn't crazy from that
point of view at all.
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It's an interesting question.
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Even if the Sun
could conceivably have...
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a binary companion...
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astronomers have never
observed a binary system...
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in which the pair of stars
are as far apart...
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as Muller claims our Sun
and Nemesis would be.
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Muller needed proof
that Nemesis was real.
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In 1997,
a Nasa mission began...
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that had the potential
to shed light on the mystery.
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The Two Micron All-Sky Survey,
or 2MASS...
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00:07:02,130 --> 00:07:04,464
used twin infrared telescopes...
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to scour the universe
for previously unknown stars.
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2MASS specialized
in hard-to-find bodies...
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in and near our galaxy...
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and to date, has produced
over two million images.
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If Nemesis was out there,
2MASS should have spotted it.
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But the survey
never detected anything...
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fitting the description
of Muller's death star.
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We've looked.
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We've looked real hard
for death star, for Nemesis...
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and we can't find it anywhere.
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But Muller isn't surprised
2MASS didn't find his Nemesis.
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The reason is at the distance
of about one light-year...
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which is the distance
it would have...
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00:07:57,894 --> 00:08:00,520
in order to have
a 26-million-year orbit...
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its motion is very little...
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00:08:02,815 --> 00:08:05,192
and so it would've been missed
by the standard surveys...
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that look for nearby stars.
129
00:08:09,155 --> 00:08:11,990
Another possibility is
that Nemesis may actually be...
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a brown dwarf.
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These failed stars...
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are much smaller
than red dwarfs...
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00:08:18,915 --> 00:08:21,041
and with a highly
elliptical orbit...
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a brown dwarf would remain far
from Earth most of the time...
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and out of the watchful eye
of astronomers.
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If that's the case...
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Nemesis could have easily
slipped under the 2MASS radar.
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Richard Muller
vows to continue looking...
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00:08:39,685 --> 00:08:46,066
and plans yet another
more detailed study.
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He believes
it's only a matter of time...
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before Nemesis is found.
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There are lots of stars
out there.
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There are millions of them.
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00:08:58,412 --> 00:09:00,330
But when you find the needle
in a haystack...
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00:09:00,373 --> 00:09:03,375
you could look at it and say,
"Well, that's not hay. "
146
00:09:03,417 --> 00:09:04,584
Similarly with this.
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When we find Nemesis,
we'll measure the orbit...
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00:09:07,129 --> 00:09:09,172
and we'll prove
that it's Nemesis.
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Of all the unexplained
mysteries in our universe...
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00:09:36,242 --> 00:09:39,369
perhaps the most tantalizing
and controversial...
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00:09:39,412 --> 00:09:42,581
is whether it's possible
to travel through time.
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Can we really travel
back in the past?
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00:09:50,256 --> 00:09:55,010
Can we really alter
our destiny?
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It was one
of the greatest questions.
155
00:10:03,060 --> 00:10:06,813
In 1955, Ron Mallett
was only 10 years old...
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00:10:06,856 --> 00:10:11,693
when his father died
of a heart attack.
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00:10:11,736 --> 00:10:13,486
Grief-stricken,
young Mallett yearned...
158
00:10:13,529 --> 00:10:15,989
for a way he could see
his father again...
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00:10:16,032 --> 00:10:20,660
and perhaps save his life.
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00:10:20,703 --> 00:10:21,995
About a year after he died...
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I came across H.G. Wells' book,
"The Time Machine"...
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and that is what saved me...
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because I thought if I could
build a time machine...
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00:10:30,296 --> 00:10:32,047
as H.G. Wells talked about...
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then I could go back
into the past...
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and try to save his life
and see him again.
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00:10:36,927 --> 00:10:38,637
And so I become obsessed
with the notion...
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of trying to build
a time machine.
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Gentlemen, I am talking
about traveling through time.
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00:10:50,900 --> 00:10:53,610
"The Time Machine"
was a work of fiction...
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00:10:53,653 --> 00:10:55,904
but Mallett soon discovered
there was science...
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00:10:55,946 --> 00:10:59,866
to support the mysterious
notion of time travel...
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00:10:59,909 --> 00:11:05,038
and the source was none other
than Albert Einstein.
174
00:11:05,081 --> 00:11:09,042
Einstein theorized that
space and time were linked...
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00:11:09,085 --> 00:11:11,086
so that one could
imagine space-time...
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as a sort of fabric or sheet.
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00:11:14,924 --> 00:11:17,300
With his general theory
of relativity...
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Einstein showed
that a massive object...
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00:11:19,345 --> 00:11:21,971
like a planet, a star,
or a black hole...
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00:11:22,014 --> 00:11:27,352
actually warps the fabric
of space and time.
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00:11:27,395 --> 00:11:29,896
In fact, Einstein
believed that gravity...
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00:11:29,939 --> 00:11:31,898
the force that binds us
to the Earth...
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00:11:31,941 --> 00:11:34,109
and keeps the Earth in orbit
around the Sun...
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is really just an effect
of this warping.
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For Mallett, this mind-
and universe-bending idea...
186
00:11:44,161 --> 00:11:47,080
has far-reaching implications...
187
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because if you could generate
enough gravity...
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00:11:49,333 --> 00:11:51,668
to twist time into a loop...
189
00:11:51,711 --> 00:11:53,336
perhaps you could
create a pathway...
190
00:11:53,379 --> 00:11:56,840
for moving backwards
and forwards through time.
191
00:12:01,429 --> 00:12:04,264
Einstein's theories
fueled Ron Mallett's quest...
192
00:12:04,306 --> 00:12:07,851
to learn how to build
his own time machine.
193
00:12:10,521 --> 00:12:12,230
But time travel
wasn't a subject...
194
00:12:12,273 --> 00:12:14,607
that could be studied
by serious scientists...
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00:12:14,650 --> 00:12:18,194
out in the open.
196
00:12:18,237 --> 00:12:19,279
As a matter of fact...
197
00:12:19,321 --> 00:12:22,115
I used a cover story
that worked for me.
198
00:12:22,158 --> 00:12:23,742
I studied black holes...
199
00:12:23,784 --> 00:12:26,327
because black holes
allowed me to understand...
200
00:12:26,370 --> 00:12:28,955
how Einstein's theory
affected time and every...
201
00:12:28,998 --> 00:12:32,500
it was a crazy idea, but it was
considered legitimate crazy.
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00:12:32,543 --> 00:12:34,627
So I built my career
on studying that...
203
00:12:34,670 --> 00:12:35,712
and being able to use...
204
00:12:35,755 --> 00:12:40,800
Einstein's General Theory
of Relativity.
205
00:12:40,843 --> 00:12:44,804
Black holes, the massive
remnants of collapsed stars...
206
00:12:44,847 --> 00:12:47,807
have an almost unmatched
gravitational power...
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00:12:47,850 --> 00:12:50,185
to distort space and time...
208
00:12:50,227 --> 00:12:54,981
which is exactly
what Mallett wanted to do.
209
00:12:55,024 --> 00:12:57,358
But how could he create
in the laboratory...
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00:12:57,401 --> 00:12:59,819
something jam-packed
with enough matter...
211
00:12:59,862 --> 00:13:03,072
to actually warp space-time?
212
00:13:03,115 --> 00:13:07,160
For inspiration, Mallett
turned again to Einstein...
213
00:13:07,203 --> 00:13:12,624
and his most famous equation,
E equals MC squared...
214
00:13:12,666 --> 00:13:14,334
which showed
that matter and energy...
215
00:13:14,376 --> 00:13:19,506
are just different forms
of the same thing.
216
00:13:19,548 --> 00:13:21,424
So following
Einstein's theory...
217
00:13:21,467 --> 00:13:23,718
light, which is energy...
218
00:13:23,761 --> 00:13:26,095
should be able to warp
space and time...
219
00:13:26,138 --> 00:13:29,849
just like a massive
object does.
220
00:13:29,892 --> 00:13:31,184
We're used to the notion...
221
00:13:31,227 --> 00:13:35,688
that gravity is created
by matter.
222
00:13:35,731 --> 00:13:38,066
But it turns out
that in Einstein's theory...
223
00:13:38,108 --> 00:13:40,360
light can create gravity...
224
00:13:40,402 --> 00:13:42,946
and that is what my work
is based on.
225
00:13:42,988 --> 00:13:48,701
In other words,
if gravity can affect time...
226
00:13:48,744 --> 00:13:51,538
and light can create gravity...
227
00:13:51,580 --> 00:13:54,249
then light can affect time.
228
00:14:04,093 --> 00:14:07,595
Mallett has built a model
to demonstrate his concept...
229
00:14:07,638 --> 00:14:11,224
that a circulating laser beam
can create a tunnel of light...
230
00:14:11,267 --> 00:14:14,519
that twists space and time.
231
00:14:14,562 --> 00:14:17,272
It has four intersecting
laser beams.
232
00:14:17,314 --> 00:14:19,774
The region
within that column of light...
233
00:14:19,817 --> 00:14:26,739
would represent the region
in which space is being twisted.
234
00:14:26,782 --> 00:14:28,950
And eventually...
235
00:14:28,993 --> 00:14:32,203
time would also get twisted
by this column of light.
236
00:14:41,005 --> 00:14:44,299
And this would allow us
to travel back into the past.
237
00:14:47,678 --> 00:14:49,095
The first time traveler...
238
00:14:49,138 --> 00:14:52,098
will have to be something much
smaller than a human being...
239
00:14:52,141 --> 00:14:55,685
a subatomic particle
like a neutron.
240
00:14:55,728 --> 00:14:57,770
What we're trying to do
is not human beings...
241
00:14:57,813 --> 00:14:59,814
but to try to send
subatomic particles...
242
00:14:59,857 --> 00:15:03,067
information at that.
243
00:15:03,110 --> 00:15:04,611
And that is a huge leap
in itself...
244
00:15:04,653 --> 00:15:05,862
because imagine...
245
00:15:05,905 --> 00:15:08,448
if we can send information
back into the past...
246
00:15:08,490 --> 00:15:11,784
that could tell us
about future disasters...
247
00:15:11,827 --> 00:15:14,245
and be able to avert
those disasters.
248
00:15:20,836 --> 00:15:22,128
We can understand...
249
00:15:22,171 --> 00:15:25,173
how circulating a light beam
can twist space and time...
250
00:15:25,215 --> 00:15:27,592
by simple analogy
with a cup of coffee.
251
00:15:27,635 --> 00:15:28,968
We think of the coffee
and the cup...
252
00:15:29,011 --> 00:15:30,011
as being like empty space...
253
00:15:30,054 --> 00:15:31,137
and we think of the spoon...
254
00:15:31,180 --> 00:15:33,181
as being like
a circulating light beam.
255
00:15:33,223 --> 00:15:35,642
You can see what happens
to the coffee as I stir it.
256
00:15:35,684 --> 00:15:36,976
The coffee swirls around.
257
00:15:37,019 --> 00:15:38,394
Well, that's what
the circulating light beam...
258
00:15:38,437 --> 00:15:40,188
is doing to empty space.
259
00:15:40,230 --> 00:15:41,814
And we could see
the effect of this...
260
00:15:41,857 --> 00:15:44,776
in the case of the coffee
by putting in a coffee bean.
261
00:15:44,818 --> 00:15:46,027
As I swirl it around...
262
00:15:46,070 --> 00:15:48,404
the coffee bean
gets swirled around.
263
00:15:48,447 --> 00:15:51,950
In the case of the laser,
as the beam is circulating...
264
00:15:51,992 --> 00:15:56,663
we put a subatomic particle
called a neutron in.
265
00:15:56,705 --> 00:15:58,122
And as we stir
the space around...
266
00:15:58,165 --> 00:15:59,791
the neutron
will get swirled around...
267
00:15:59,833 --> 00:16:04,295
just like the coffee bean.
268
00:16:04,338 --> 00:16:06,172
Now, remember,
in Einstein's theory...
269
00:16:06,215 --> 00:16:07,674
space and time are connected...
270
00:16:07,716 --> 00:16:09,842
so that swirling of space
will cause...
271
00:16:09,885 --> 00:16:12,387
the straight line of time
to be swirled into a loop.
272
00:16:15,224 --> 00:16:17,475
And along that loop in time
we can go from the past...
273
00:16:17,518 --> 00:16:18,851
to the present,
to the future...
274
00:16:18,894 --> 00:16:20,478
and then back into the past.
275
00:16:26,944 --> 00:16:29,070
Science fiction has depicted
time machines...
276
00:16:29,113 --> 00:16:33,324
as allowing unrestrained travel
forward and backwards in time.
277
00:16:39,164 --> 00:16:41,249
But Mallett cautions
that a time traveler...
278
00:16:41,291 --> 00:16:43,251
could only journey back
as far as the moment...
279
00:16:43,293 --> 00:16:47,505
that the time machine
was first turned on.
280
00:16:47,548 --> 00:16:49,966
In other words, if I
turned the device on today...
281
00:16:50,009 --> 00:16:52,301
and I leave it on
for a hundred years...
282
00:16:52,344 --> 00:16:53,845
then someone
a hundred years from now...
283
00:16:53,887 --> 00:16:57,140
could travel back 75 years,
50 years, 25 years...
284
00:16:57,182 --> 00:16:59,684
all the way back to the moment
I turned the device on.
285
00:16:59,727 --> 00:17:01,686
But they can't travel
earlier than that...
286
00:17:01,729 --> 00:17:04,689
because the device didn't
exist earlier than that...
287
00:17:04,732 --> 00:17:07,066
and it's the device
that's creating the effect...
288
00:17:07,109 --> 00:17:09,068
so there's nothing for them
to time-travel...
289
00:17:09,111 --> 00:17:13,740
to materialize into.
290
00:17:13,782 --> 00:17:16,367
This limitation means
that Mallett's time machine...
291
00:17:16,410 --> 00:17:17,785
could never give him
the capability...
292
00:17:17,828 --> 00:17:23,791
to travel back to 1955
to save his father's life.
293
00:17:23,834 --> 00:17:26,169
To do that would take
some technology...
294
00:17:26,211 --> 00:17:28,087
from out of this world.
295
00:17:31,300 --> 00:17:32,592
Theoretically...
296
00:17:32,634 --> 00:17:35,428
an advanced alien civilization
might have a time machine...
297
00:17:35,471 --> 00:17:38,598
that was switched on
thousands of years ago.
298
00:17:42,478 --> 00:17:45,438
We may be able to use
their time travel...
299
00:17:45,481 --> 00:17:47,857
to go back to visit
our ancient past...
300
00:17:47,900 --> 00:17:50,485
because if they have developed
time travel...
301
00:17:50,527 --> 00:17:52,528
let's say, 10,000 years ago...
302
00:17:52,571 --> 00:17:54,197
it would still have
the same limitation...
303
00:17:54,239 --> 00:17:56,449
but once we encounter them,
we could use it...
304
00:17:56,492 --> 00:17:57,825
and perhaps someday...
305
00:17:57,868 --> 00:18:00,995
we may be able to visit
ancient Egypt and ancient Rome.
306
00:18:06,210 --> 00:18:07,251
For now, Mallett is focused...
307
00:18:07,294 --> 00:18:11,881
on getting
his time machine built...
308
00:18:11,924 --> 00:18:18,846
a project that will require
$250,000 in startup costs alone.
309
00:18:18,889 --> 00:18:21,808
Money is just one obstacle
facing any physicist...
310
00:18:21,850 --> 00:18:26,062
daring to dabble
in time travel.
311
00:18:26,105 --> 00:18:27,814
There are also
certain paradoxes...
312
00:18:27,856 --> 00:18:31,776
that many believe
make time travel impossible...
313
00:18:31,819 --> 00:18:35,238
like the infamous
grandfather paradox.
314
00:18:35,280 --> 00:18:38,658
Imagine you go back in time
and kill your own grandfather...
315
00:18:38,700 --> 00:18:42,703
before he meets
your grandmother.
316
00:18:42,746 --> 00:18:44,497
Therefore, you never
would've been born...
317
00:18:44,540 --> 00:18:46,624
and therefore couldn't
have gone back in time...
318
00:18:46,667 --> 00:18:48,417
in the first place.
319
00:18:48,460 --> 00:18:49,669
And then the loop
is set up of...
320
00:18:49,711 --> 00:18:51,295
possible, impossible...
321
00:18:51,338 --> 00:18:55,091
happened, it didn't happen.
322
00:18:55,134 --> 00:18:56,134
But Mallett believes...
323
00:18:56,176 --> 00:18:58,469
recent advances
in theoretical physics...
324
00:18:58,512 --> 00:19:02,974
suggest that these paradoxes
aren't a problem at all.
325
00:19:03,016 --> 00:19:06,185
Many physicists now believe
in the far-out notion...
326
00:19:06,228 --> 00:19:07,228
that our universe...
327
00:19:07,271 --> 00:19:13,234
is just one of many
parallel universes.
328
00:19:13,277 --> 00:19:15,111
So that when you
go back in time...
329
00:19:15,154 --> 00:19:17,989
you might actually be entering
a parallel universe...
330
00:19:18,031 --> 00:19:19,699
in which you can alter events...
331
00:19:19,741 --> 00:19:25,746
without affecting
the universe you came from.
332
00:19:25,789 --> 00:19:29,876
We believe that the river
of time can have whirlpools...
333
00:19:29,918 --> 00:19:32,378
whirlpools by which
you may be able to go back...
334
00:19:32,421 --> 00:19:34,881
and meet your parents
before you're born...
335
00:19:34,923 --> 00:19:37,300
or perhaps even fork
into two rivers...
336
00:19:37,342 --> 00:19:40,052
by which you can
actually alter the past...
337
00:19:40,095 --> 00:19:42,096
to create
an alternate universe.
338
00:19:42,139 --> 00:19:43,347
These are all theories...
339
00:19:43,390 --> 00:19:47,059
that are at the very forefront
of modern physics today.
340
00:19:50,606 --> 00:19:53,691
Mallett believes we may be
as little as a century away...
341
00:19:53,734 --> 00:19:56,235
from time travel by humans.
342
00:19:56,278 --> 00:19:58,905
Still too late for him
to travel back in time...
343
00:19:58,947 --> 00:20:00,281
to save his father.
344
00:20:00,324 --> 00:20:01,324
- And your name?
- Rocky.
345
00:20:01,366 --> 00:20:03,159
- Nice to meet you.
- Okay, thank you.
346
00:20:03,202 --> 00:20:05,161
Remember what's happening
to space.
347
00:20:05,204 --> 00:20:06,287
It's swirling around.
348
00:20:06,330 --> 00:20:09,081
But his personal loss
has opened a door...
349
00:20:09,124 --> 00:20:12,043
for a new world
for future generations.
350
00:20:12,085 --> 00:20:18,424
I developed the basic
equations for this.
351
00:20:18,467 --> 00:20:21,260
It has led to my being able...
352
00:20:21,303 --> 00:20:24,013
to share something
with the world...
353
00:20:24,056 --> 00:20:28,267
that I would never have been
able to share before.
354
00:20:28,310 --> 00:20:30,853
And I feel that-
that it's actually...
355
00:20:30,896 --> 00:20:35,816
a fitting memorial
to my father...
356
00:20:35,859 --> 00:20:37,944
that I've been able
to do that.
357
00:20:37,986 --> 00:20:39,528
I feel very good about that.
358
00:21:01,718 --> 00:21:07,139
As the universe
was first forming...
359
00:21:07,182 --> 00:21:08,432
scientists believe...
360
00:21:08,475 --> 00:21:11,018
it was comprised of more
than just the regular matter...
361
00:21:11,061 --> 00:21:15,856
that now makes up
everything around us.
362
00:21:15,899 --> 00:21:16,899
They believe it had...
363
00:21:16,942 --> 00:21:19,527
an almost equal amount
of anti-matter...
364
00:21:19,569 --> 00:21:24,740
matter's elusive evil twin.
365
00:21:24,783 --> 00:21:27,159
If you go back
to the very early universe...
366
00:21:27,202 --> 00:21:31,789
it turns out that it was made
of matter and anti-matter.
367
00:21:31,832 --> 00:21:36,210
It turns out that every particle
has an anti-particle.
368
00:21:36,253 --> 00:21:39,088
And it sounds kind of crazy,
but it's real...
369
00:21:39,131 --> 00:21:42,591
and sort of sci-fi,
you know, anti-matter.
370
00:21:42,634 --> 00:21:45,011
But what is this
mysterious anti-matter...
371
00:21:45,053 --> 00:21:47,555
and where did all of it go?
372
00:21:47,597 --> 00:21:50,933
Anti-matter
is exactly like matter.
373
00:21:50,976 --> 00:21:52,643
The difference
between it is the fact...
374
00:21:52,686 --> 00:21:54,979
that it has a completely
different charge...
375
00:21:55,022 --> 00:21:59,108
associated with it.
376
00:21:59,151 --> 00:22:01,152
Regular matter
is made of atoms...
377
00:22:01,194 --> 00:22:03,863
which in turn are made
of subatomic particles...
378
00:22:03,905 --> 00:22:06,365
like negatively charged
electrons...
379
00:22:06,408 --> 00:22:11,996
and positively charged
protons.
380
00:22:12,039 --> 00:22:14,874
Anti-matter are the opposite
of these particles.
381
00:22:14,916 --> 00:22:16,042
They have the same mass...
382
00:22:16,084 --> 00:22:19,170
but the opposite
electrical charge.
383
00:22:19,212 --> 00:22:20,796
Proton's a positively
charged particle...
384
00:22:20,839 --> 00:22:22,465
that's the nucleus
of the atom.
385
00:22:22,507 --> 00:22:25,718
The anti-proton would be
a negatively charged proton...
386
00:22:25,761 --> 00:22:31,057
that has exactly the same mass.
387
00:22:31,099 --> 00:22:33,934
In our universe,
opposites attract...
388
00:22:33,977 --> 00:22:37,563
and particles and anti-particles
are pulled together.
389
00:22:37,606 --> 00:22:38,606
One would think this is...
390
00:22:38,648 --> 00:22:43,319
a relationship
made for the heavens.
391
00:22:43,362 --> 00:22:46,238
But every time matter comes
in contact with anti-matter...
392
00:22:46,281 --> 00:22:50,493
the outcome is the same...
393
00:22:50,535 --> 00:22:56,540
they annihilate each other.
394
00:22:56,583 --> 00:22:59,168
Imagine two spaceships
hurtling through space...
395
00:22:59,211 --> 00:23:03,339
on a collision course.
396
00:23:03,382 --> 00:23:09,345
One is made of regular matter.
397
00:23:09,388 --> 00:23:11,597
The other is
an anti-matter craft...
398
00:23:11,640 --> 00:23:17,895
built by an alien
civilization.
399
00:23:17,938 --> 00:23:20,481
The impact
would be spectacular...
400
00:23:20,524 --> 00:23:22,608
and there would be
no wreckage left behind...
401
00:23:22,651 --> 00:23:25,778
for cosmic crash investigators
to examine.
402
00:23:29,991 --> 00:23:32,159
The matter and the anti-matter
disappear.
403
00:23:32,202 --> 00:23:33,536
Poof, they're gone.
404
00:23:33,578 --> 00:23:35,996
But the energy
doesn't disappear.
405
00:23:36,039 --> 00:23:38,082
The energy re-emerges
in the form...
406
00:23:38,125 --> 00:23:42,795
of two very energetic
gamma rays: photons.
407
00:23:42,838 --> 00:23:45,714
And the amount of energy...
408
00:23:45,757 --> 00:23:47,466
locked up
in a tiny amount of mass...
409
00:23:47,509 --> 00:23:51,554
is quite astonishing.
410
00:23:51,596 --> 00:23:53,472
If you take matter
and anti-matter...
411
00:23:53,515 --> 00:23:56,767
and combine it,
it is explosive.
412
00:23:56,810 --> 00:23:58,978
And in fact, it is one
of the greatest sources...
413
00:23:59,020 --> 00:24:00,813
of energy in the universe...
414
00:24:00,856 --> 00:24:03,524
the collision of matter
and anti-matter.
415
00:24:03,567 --> 00:24:04,650
So if I were you...
416
00:24:04,693 --> 00:24:06,610
I would not put anti-matter
in your pocket...
417
00:24:06,653 --> 00:24:11,657
if you know what's good
for you.
418
00:24:11,700 --> 00:24:14,577
Volatile as anti-matter
is when it meets matter...
419
00:24:14,619 --> 00:24:16,704
there's a tremendous
energy potential...
420
00:24:16,746 --> 00:24:18,706
if we knew how
to harness it.
421
00:24:18,748 --> 00:24:19,832
So to get an idea...
422
00:24:19,875 --> 00:24:23,377
how much energy
is locked up in matter...
423
00:24:23,420 --> 00:24:24,628
if you imagine for a minute...
424
00:24:24,671 --> 00:24:26,630
that these two piles
of sand are...
425
00:24:26,673 --> 00:24:29,884
that one is matter
and one is anti-matter...
426
00:24:29,926 --> 00:24:32,261
and you let them
come together...
427
00:24:32,304 --> 00:24:34,680
they would annihilate
and produce energy.
428
00:24:34,723 --> 00:24:35,973
How much energy?
429
00:24:36,016 --> 00:24:39,059
Enough energy to power
all of California for a week...
430
00:24:39,102 --> 00:24:43,856
just in those
two piles of sand.
431
00:24:43,899 --> 00:24:49,028
The biggest mystery surrounding
anti-matter is this...
432
00:24:49,070 --> 00:24:50,738
if there were nearly
equal amounts...
433
00:24:50,780 --> 00:24:54,992
of matter and anti-matter
in the early universe...
434
00:24:55,035 --> 00:24:59,622
then where is
all the anti-matter now?
435
00:24:59,664 --> 00:25:01,749
One of the great mysteries
of the universe...
436
00:25:01,791 --> 00:25:08,297
is what happened to our
evil twin, anti-matter.
437
00:25:08,340 --> 00:25:09,548
Everywhere we look
in the heavens...
438
00:25:09,591 --> 00:25:11,050
we see ordinary matter.
439
00:25:11,092 --> 00:25:13,552
We don't see anti-matter.
440
00:25:13,595 --> 00:25:15,346
There's only a small amount
of anti-matter...
441
00:25:15,388 --> 00:25:18,182
coming out of the center
of the Milky Way galaxy.
442
00:25:22,938 --> 00:25:26,398
Why this universe appears
to be made entirely of matter...
443
00:25:26,441 --> 00:25:29,568
and there isn't much anti-matter
to be seen out there...
444
00:25:29,611 --> 00:25:30,903
is a mystery.
445
00:25:30,946 --> 00:25:32,947
I don't think it'll ever
be explained anyway...
446
00:25:32,989 --> 00:25:36,575
but the mind hunts
for an explanation.
447
00:25:39,704 --> 00:25:42,039
One possibility is
that perhaps there was...
448
00:25:42,082 --> 00:25:45,042
a slightly higher percentage
of matter than anti-matter...
449
00:25:45,085 --> 00:25:48,963
in the early universe.
450
00:25:49,005 --> 00:25:51,840
So as the particles
and anti-particles collided...
451
00:25:51,883 --> 00:25:53,634
in a war of annihilation...
452
00:25:53,677 --> 00:25:59,139
that small percentage
of matter survived...
453
00:25:59,182 --> 00:26:02,977
the last living veterans of
our most ancient battlefield.
454
00:26:06,731 --> 00:26:10,317
For every billion
anti-protons...
455
00:26:10,360 --> 00:26:13,571
you need a billion
and one protons.
456
00:26:13,613 --> 00:26:16,198
Then the billion
all annihilate...
457
00:26:16,241 --> 00:26:18,158
and you're left
with that one proton.
458
00:26:23,373 --> 00:26:28,794
And the leftover is us.
459
00:26:28,837 --> 00:26:30,296
We are the residue.
460
00:26:30,338 --> 00:26:34,258
We are the leftover of this
titanic blast of energy...
461
00:26:34,301 --> 00:26:37,303
released by the collision
of matter and anti-matter...
462
00:26:37,345 --> 00:26:39,346
at the instant of time.
463
00:26:47,355 --> 00:26:49,815
Our most advanced theories
cannot explain...
464
00:26:49,858 --> 00:26:54,695
why there was this asymmetry
between matter and anti-matter.
465
00:26:54,738 --> 00:26:56,405
But thank God it exists.
466
00:26:56,448 --> 00:26:58,115
Otherwise,
we wouldn't be here.
467
00:27:02,996 --> 00:27:04,580
But even though
matter prevailed...
468
00:27:04,623 --> 00:27:08,083
to make up everything
we see around us...
469
00:27:08,126 --> 00:27:11,879
could there be distant galaxies
or regions of space...
470
00:27:11,921 --> 00:27:15,257
where anti-matter
still reigns supreme?
471
00:27:15,300 --> 00:27:17,801
It may be that there are
entire galaxies...
472
00:27:17,844 --> 00:27:21,347
that are just 99.9 percent
anti-matter...
473
00:27:21,389 --> 00:27:23,432
just like this one is matter.
474
00:27:23,475 --> 00:27:24,850
And if an anti-matter galaxy...
475
00:27:24,893 --> 00:27:26,935
were to run into
a matter galaxy...
476
00:27:26,978 --> 00:27:28,312
then they both
would be annihilated...
477
00:27:28,355 --> 00:27:34,568
in some stupendous flash
of light and power.
478
00:27:34,611 --> 00:27:36,362
As strange as it is...
479
00:27:36,404 --> 00:27:38,364
scientists have learned
how to create...
480
00:27:38,406 --> 00:27:40,783
minute quantities
of anti-matter...
481
00:27:40,825 --> 00:27:43,911
in laboratory accelerators
for medical purposes.
482
00:27:48,708 --> 00:27:49,875
Particles of anti-matter...
483
00:27:49,918 --> 00:27:52,086
from decaying
radioactive material...
484
00:27:52,128 --> 00:27:54,129
are injected into the body...
485
00:27:54,172 --> 00:27:59,635
to create PET scans
of the brain.
486
00:27:59,678 --> 00:28:00,803
Many people don't realize...
487
00:28:00,845 --> 00:28:02,471
that when they go
to the hospital...
488
00:28:02,514 --> 00:28:04,223
and have a PET scan...
489
00:28:04,265 --> 00:28:05,891
they're actually
being injected...
490
00:28:05,934 --> 00:28:08,519
with a source of anti-matter.
491
00:28:08,561 --> 00:28:12,314
The P in PET corresponds
to positrons.
492
00:28:12,357 --> 00:28:14,858
Positrons are anti-electrons.
493
00:28:14,901 --> 00:28:17,903
And when-and it goes
to some part of the body...
494
00:28:17,946 --> 00:28:19,697
that we're trying to figure out
what's going on...
495
00:28:19,739 --> 00:28:21,949
then when
the positron's emitted...
496
00:28:21,991 --> 00:28:23,409
it finds an electron
very quickly...
497
00:28:23,451 --> 00:28:24,493
annihilates with it...
498
00:28:24,536 --> 00:28:26,578
and the gamma rays
come out of the body...
499
00:28:26,621 --> 00:28:28,414
and are detected.
500
00:28:28,456 --> 00:28:30,374
It concentrates
in the parts of the brain...
501
00:28:30,417 --> 00:28:32,418
where there's mental activity...
502
00:28:32,460 --> 00:28:34,002
and then we can detect
the emission...
503
00:28:34,045 --> 00:28:36,672
of positron radiation.
504
00:28:36,715 --> 00:28:38,257
So this allows brain scans...
505
00:28:38,299 --> 00:28:42,553
to give us gorgeous photographs
of the thinking brain...
506
00:28:42,595 --> 00:28:47,141
made possible by anti-matter.
507
00:28:47,183 --> 00:28:48,976
While anti-matter
has helped to unlock...
508
00:28:49,018 --> 00:28:51,687
the secrets
of the human brain...
509
00:28:51,730 --> 00:28:53,814
the human brain
has yet to unlock...
510
00:28:53,857 --> 00:28:56,775
all the secrets
of anti-matter.
511
00:28:56,818 --> 00:28:57,901
We do not know why...
512
00:28:57,944 --> 00:29:01,780
the universe
is made of matter now...
513
00:29:01,823 --> 00:29:06,326
but we are making progress
towards answering that question.
514
00:29:06,369 --> 00:29:11,582
You know,
little steps at a time.
515
00:29:11,624 --> 00:29:15,127
Like many mysteries in our
ever-changing universe...
516
00:29:15,170 --> 00:29:18,172
the truth about anti-matter
may remain for now...
517
00:29:18,214 --> 00:29:20,758
in the realm
of the unexplained.
518
00:29:28,516 --> 00:29:32,561
Mars and mystery have always
gone hand in hand.
519
00:29:37,859 --> 00:29:40,319
But the most intriguing
mystery of the red planet...
520
00:29:40,361 --> 00:29:43,363
has nothing to do
with alien invaders.
521
00:29:52,707 --> 00:29:54,583
Scientific evidence
suggests that Mars...
522
00:29:54,626 --> 00:29:57,002
was once a more
Earth-like planet...
523
00:29:57,045 --> 00:30:02,508
with one of the key elements
to support life...
524
00:30:02,550 --> 00:30:04,676
water.
525
00:30:04,719 --> 00:30:09,681
Water existed
in abundance on Mars.
526
00:30:09,724 --> 00:30:12,059
We find the evidence
of old flows.
527
00:30:12,101 --> 00:30:14,561
We see a little tiny bit
of water vapor...
528
00:30:14,604 --> 00:30:17,564
in the atmosphere.
529
00:30:17,607 --> 00:30:19,358
There are even
features on Mars...
530
00:30:19,400 --> 00:30:22,986
that look like old river valleys
and flood plains.
531
00:30:27,200 --> 00:30:30,994
It was once a tropical planet
with oceans and seas...
532
00:30:31,037 --> 00:30:34,790
but all that water disappeared.
533
00:30:34,833 --> 00:30:38,418
How could all the water
on Mars have simply vanished?
534
00:30:38,461 --> 00:30:41,505
And why did it disappear?
535
00:30:41,548 --> 00:30:42,548
These are mysteries...
536
00:30:42,590 --> 00:30:47,135
that scientists
are struggling to solve.
537
00:30:47,178 --> 00:30:51,223
Geologic evidence gathered by
the Mars rovers and orbiters...
538
00:30:51,266 --> 00:30:54,476
suggest that 3.5 billion
years ago...
539
00:30:54,519 --> 00:30:58,689
Mars' watery surface
changed dramatically.
540
00:30:58,731 --> 00:31:02,317
The once-temperate planet
became a cold, dry place...
541
00:31:02,360 --> 00:31:06,238
and the water vanished.
542
00:31:06,281 --> 00:31:08,365
But figuring out
when the water disappeared...
543
00:31:08,408 --> 00:31:13,078
doesn't tell you
where it went or why.
544
00:31:13,121 --> 00:31:15,163
The water on Mars was lost...
545
00:31:15,206 --> 00:31:18,041
a very, very, very
long time ago...
546
00:31:18,084 --> 00:31:20,002
and I'm talking
billions of years.
547
00:31:20,044 --> 00:31:23,630
And the clues
that would lead you to know...
548
00:31:23,673 --> 00:31:25,757
where that water went
are long gone.
549
00:31:32,473 --> 00:31:34,266
A series of events on Mars...
550
00:31:34,309 --> 00:31:40,105
appears to have drastically
changed the watery landscape.
551
00:31:40,148 --> 00:31:43,025
Mars endured an intense period
of volcanism...
552
00:31:43,067 --> 00:31:49,698
that spewed lava
across the surface.
553
00:31:49,741 --> 00:31:51,116
When it finally ended...
554
00:31:51,159 --> 00:31:55,162
the planet's molten iron core
solidified.
555
00:31:55,204 --> 00:31:56,955
This may have been
what caused Mars...
556
00:31:56,998 --> 00:32:01,752
to lose its magnetic field
and protective ozone layer.
557
00:32:01,794 --> 00:32:03,462
This left the atmosphere
vulnerable...
558
00:32:03,504 --> 00:32:05,964
to the solar wind
from our Sun...
559
00:32:06,007 --> 00:32:09,635
which is quite powerful.
560
00:32:09,677 --> 00:32:13,305
Solar winds pummeled the planet
for millions of years...
561
00:32:13,348 --> 00:32:17,142
stripping
any remaining atmosphere.
562
00:32:17,185 --> 00:32:21,063
Now water vapor that once
fell as snow or rain...
563
00:32:21,105 --> 00:32:25,108
escaped the planet's
small gravitational field.
564
00:32:25,151 --> 00:32:27,945
The water is brought up
into the atmosphere...
565
00:32:27,987 --> 00:32:29,446
as water vapor...
566
00:32:29,489 --> 00:32:32,324
and it's bombarded
by ultraviolet radiation...
567
00:32:32,367 --> 00:32:35,494
which can split water,
which is H20...
568
00:32:35,536 --> 00:32:36,954
into hydrogen and oxygen.
569
00:32:36,996 --> 00:32:39,247
And the hydrogen,
being the lightest gas known...
570
00:32:39,290 --> 00:32:43,168
floats up to the top
of the atmosphere...
571
00:32:43,211 --> 00:32:47,589
and can get swept away
by the solar winds.
572
00:32:53,554 --> 00:32:56,014
Another theory
for the loss of Mars' water...
573
00:32:56,057 --> 00:33:00,268
involves a threat
from outside the planet.
574
00:33:00,311 --> 00:33:01,895
There's evidence
that in the early years...
575
00:33:01,938 --> 00:33:03,480
of the solar system...
576
00:33:03,523 --> 00:33:06,900
Mars resided in
a deadly flight path.
577
00:33:06,943 --> 00:33:10,153
There's one cluster,
about 3.9 billion years ago...
578
00:33:10,196 --> 00:33:12,030
called the great bombardment...
579
00:33:12,073 --> 00:33:14,199
that really must have
peppered that planet...
580
00:33:14,242 --> 00:33:16,451
with many, many impacts.
581
00:33:16,494 --> 00:33:17,703
And that kind of an event...
582
00:33:17,745 --> 00:33:20,872
would have actually thrown
material and atmosphere...
583
00:33:20,915 --> 00:33:22,207
right off of the planet...
584
00:33:22,250 --> 00:33:27,546
and outside of
the gravitational field.
585
00:33:27,588 --> 00:33:32,801
Let's imagine that we
have an asteroid here...
586
00:33:32,844 --> 00:33:35,887
and this asteroid is really
the size of a mountain.
587
00:33:35,930 --> 00:33:42,060
And imagine this is
tumbling through space...
588
00:33:42,103 --> 00:33:44,646
at very high speed...
589
00:33:44,689 --> 00:33:50,193
and we're talking tens of
thousands of miles per hour.
590
00:33:50,236 --> 00:33:54,197
If we come zipping
in at high speed...
591
00:33:54,240 --> 00:33:55,240
splat.
592
00:33:59,620 --> 00:34:01,705
It's lost to space.
593
00:34:01,748 --> 00:34:02,831
Much of it will sink in.
594
00:34:02,874 --> 00:34:04,541
Some will become
atmospheric gases...
595
00:34:04,584 --> 00:34:06,043
sputtered away to space.
596
00:34:06,085 --> 00:34:07,794
Some will be lost.
597
00:34:12,800 --> 00:34:16,261
Other answers to the mystery
of Mars' disappearing water...
598
00:34:16,304 --> 00:34:21,850
may be hidden deep inside
the red planet.
599
00:34:21,893 --> 00:34:24,936
Some of the water combined
with carbon dioxide...
600
00:34:24,979 --> 00:34:28,231
to form polar ice caps
up to two miles deep...
601
00:34:28,274 --> 00:34:35,113
and a permafrost that covers
much of the surface.
602
00:34:35,156 --> 00:34:37,491
But there's evidence
that beneath the ice...
603
00:34:37,533 --> 00:34:40,786
liquid water still flows.
604
00:34:40,828 --> 00:34:43,497
Much of the water on Mars
has gone underground...
605
00:34:43,539 --> 00:34:45,040
and some of it certainly
has migrated...
606
00:34:45,083 --> 00:34:47,292
down to a depth
where it's warm enough...
607
00:34:47,335 --> 00:34:54,841
for it to exist
as liquid water.
608
00:34:54,884 --> 00:34:56,218
Then when it gets colder...
609
00:34:56,260 --> 00:34:58,804
it's gonna be frozen into
a cryosphere, if you like...
610
00:34:58,846 --> 00:35:01,681
an ice part of the subsurface.
611
00:35:01,724 --> 00:35:03,683
Then near the surface,
it's gonna dry out...
612
00:35:03,726 --> 00:35:06,061
as the water can move
through the soil...
613
00:35:06,104 --> 00:35:12,651
and go into the atmosphere.
614
00:35:12,693 --> 00:35:15,403
University of Arizona
scientist Peter Smith...
615
00:35:15,446 --> 00:35:19,991
is eager to solve the mystery
of Mars' disappearing water.
616
00:35:20,034 --> 00:35:22,410
Okay, I'm digging
a little trench here...
617
00:35:22,453 --> 00:35:23,995
to show you what happens...
618
00:35:24,038 --> 00:35:28,166
if you get below the absolute
hyper-arid surface...
619
00:35:28,209 --> 00:35:30,502
and go down just a foot or so...
620
00:35:30,545 --> 00:35:32,003
because this is similar...
621
00:35:32,046 --> 00:35:35,882
to what we're gonna be
doing on Mars.
622
00:35:35,925 --> 00:35:38,260
Smith is the principle
investigator...
623
00:35:38,302 --> 00:35:42,347
for Nasa's
Phoenix Mars mission.
624
00:35:42,390 --> 00:35:45,517
It's a robotic probe
with one simple objective...
625
00:35:45,560 --> 00:35:50,897
land on Mars
and follow the water.
626
00:35:50,940 --> 00:35:52,440
What happened to that water?
627
00:35:52,483 --> 00:35:53,984
It could have frozen
into underground ice...
628
00:35:54,026 --> 00:35:56,486
or even aquifers
of liquid water.
629
00:35:56,529 --> 00:35:58,238
These are something
we're looking for today...
630
00:35:58,281 --> 00:36:00,198
using radio and radar...
631
00:36:00,241 --> 00:36:03,243
to penetrate through the surface
and try and locate...
632
00:36:03,286 --> 00:36:06,371
these reservoirs of water.
633
00:36:06,414 --> 00:36:09,040
Smith believes
that Arizona's Wilcox Playa...
634
00:36:09,083 --> 00:36:10,792
reflects what scientists
will find...
635
00:36:10,835 --> 00:36:15,463
when Phoenix finally scratches
the red Martian surface.
636
00:36:15,506 --> 00:36:18,758
Even though the surface
is parched and salty and dry...
637
00:36:18,801 --> 00:36:20,760
just within six inches
of the surface...
638
00:36:20,803 --> 00:36:24,431
is a very wet clay
like a reservoir of water...
639
00:36:24,473 --> 00:36:27,100
and there's a whole
ecosystem of life...
640
00:36:27,143 --> 00:36:29,227
that's living
in these wet soils...
641
00:36:29,270 --> 00:36:30,729
and these clays.
642
00:36:30,771 --> 00:36:33,481
When it rains,
it comes to the surface.
643
00:36:33,524 --> 00:36:35,400
And, in fact,
you see little pools...
644
00:36:35,443 --> 00:36:37,736
where actually brine shrimp...
645
00:36:37,778 --> 00:36:40,530
that are locked
into these soils.
646
00:36:40,573 --> 00:36:42,699
We wonder if we get down
under the surface...
647
00:36:42,742 --> 00:36:44,409
at the right place on Mars...
648
00:36:44,452 --> 00:36:48,079
and that is
the permafrost region...
649
00:36:48,122 --> 00:36:50,624
can we find
the same sort of ecosystem...
650
00:36:50,666 --> 00:36:52,709
around the ice...
651
00:36:52,752 --> 00:36:54,753
melting over time
as climate changes?
652
00:36:54,795 --> 00:37:02,844
It's habitable for some sort
of Martian life forms.
653
00:37:02,887 --> 00:37:04,471
Some believe
that life on Earth...
654
00:37:04,513 --> 00:37:05,847
originated on Mars...
655
00:37:05,890 --> 00:37:07,682
and that its strange
transformation...
656
00:37:07,725 --> 00:37:13,396
foretells our destiny.
657
00:37:13,439 --> 00:37:15,857
If that's true,
finding Mars' water...
658
00:37:15,900 --> 00:37:18,902
may lead us back
to our cosmic beginnings...
659
00:37:18,945 --> 00:37:21,071
and into the future.
660
00:37:33,876 --> 00:37:35,794
When it comes to the universe...
661
00:37:35,836 --> 00:37:41,967
what we know is surpassed only
by what we have yet to learn.
662
00:37:42,009 --> 00:37:44,302
And of all
the unexplained mysteries...
663
00:37:44,345 --> 00:37:49,808
one remains
the greatest of all.
664
00:37:49,850 --> 00:37:54,646
Did anything come
before the Big Bang...
665
00:37:54,689 --> 00:37:58,650
or was that event truly
the beginning of everything?
666
00:37:58,693 --> 00:38:02,821
And if it was,
what was the spark that lit it?
667
00:38:02,863 --> 00:38:07,242
This is the greatest mystery
in all of science.
668
00:38:07,285 --> 00:38:11,121
What started creation itself?
669
00:38:11,163 --> 00:38:14,749
Big bang theory
has this tremendous hole in it.
670
00:38:14,792 --> 00:38:16,501
We are clueless.
671
00:38:16,544 --> 00:38:21,006
We are clueless as to what
set the Big Bang into motion.
672
00:38:36,355 --> 00:38:39,107
The Big Bang
is the cosmological model...
673
00:38:39,150 --> 00:38:45,363
for the birth of our universe,
13.7 billion years ago.
674
00:38:45,406 --> 00:38:46,573
Everything in our universe...
675
00:38:46,615 --> 00:38:52,037
can be traced back
to that moment.
676
00:38:52,079 --> 00:38:53,204
There seems to be...
677
00:38:53,247 --> 00:38:55,248
this mysterious point
at the beginning...
678
00:38:55,291 --> 00:38:56,958
and we call it
the singularity.
679
00:38:57,001 --> 00:38:58,877
But even though
it's mysterious...
680
00:38:58,919 --> 00:39:03,173
and has many open questions
associated with it...
681
00:39:03,215 --> 00:39:04,883
it still makes
a good starting point...
682
00:39:04,925 --> 00:39:08,595
for our timeline.
683
00:39:08,637 --> 00:39:11,306
But our scientific instruments
are blind and deaf...
684
00:39:11,349 --> 00:39:13,725
to the period
before the Big Bang...
685
00:39:13,768 --> 00:39:18,563
if such a period
existed at all.
686
00:39:18,606 --> 00:39:19,981
The singularity is like...
687
00:39:20,024 --> 00:39:27,072
a horizon that we can
never see beyond.
688
00:39:27,114 --> 00:39:28,281
Because in the creation...
689
00:39:28,324 --> 00:39:30,158
time was created
along with space...
690
00:39:30,201 --> 00:39:32,035
and along with matter...
691
00:39:32,078 --> 00:39:39,667
and the Big Bang
is just that sort of event.
692
00:39:39,710 --> 00:39:44,089
And therefore, it's impossible
to know what happened...
693
00:39:44,131 --> 00:39:48,760
before the creation event.
694
00:39:48,803 --> 00:39:51,554
Nevertheless,
scientific speculation...
695
00:39:51,597 --> 00:39:53,681
as to what happened
before the Big Bang...
696
00:39:53,724 --> 00:39:54,974
is something that intrigues...
697
00:39:55,017 --> 00:39:57,519
the greatest minds
in astrophysics.
698
00:40:06,320 --> 00:40:08,613
Some theorists believe
that our universe...
699
00:40:08,656 --> 00:40:15,620
experiences Big Bangs
at regular intervals.
700
00:40:15,663 --> 00:40:19,165
This cyclic model proposes
that every trillion years...
701
00:40:19,208 --> 00:40:22,252
there's a Big Bang after which
the universe expands...
702
00:40:22,294 --> 00:40:23,628
before again collapsing...
703
00:40:23,671 --> 00:40:29,509
setting the stage
for another Big Bang.
704
00:40:29,552 --> 00:40:31,803
There's interesting ways
that can connect...
705
00:40:31,846 --> 00:40:34,973
with the story
of a previous universe.
706
00:40:35,015 --> 00:40:42,272
The end of one universe can
bring the beginning of another.
707
00:40:42,314 --> 00:40:43,606
Maybe there never was a start...
708
00:40:43,649 --> 00:40:47,819
that it's somehow been ongoing
from an earlier moment...
709
00:40:47,862 --> 00:40:51,990
and never had a creator
at all.
710
00:40:58,831 --> 00:41:01,624
But we might be closer
to an explanation...
711
00:41:01,667 --> 00:41:04,919
of the pre-Big Bang
than we know.
712
00:41:04,962 --> 00:41:07,839
The cosmic reverberations
from the Big Bang...
713
00:41:07,882 --> 00:41:09,507
that still echo
through the universe...
714
00:41:09,550 --> 00:41:11,342
may actually hold the answer...
715
00:41:11,385 --> 00:41:14,304
to the moment
before the singularity.
716
00:41:14,346 --> 00:41:15,847
It turns out
these standing waves...
717
00:41:15,890 --> 00:41:19,809
are key to how we understand
the universe today.
718
00:41:19,852 --> 00:41:21,144
Inflation gives the universe...
719
00:41:21,187 --> 00:41:22,604
one big hit at the beginning...
720
00:41:22,646 --> 00:41:26,691
just like I'm hitting
the pot right here.
721
00:41:26,734 --> 00:41:28,693
It forms the standing waves...
722
00:41:28,736 --> 00:41:31,029
and we can look for those
symmetrical patterns...
723
00:41:31,071 --> 00:41:32,989
in the cosmic radiation today.
724
00:41:37,912 --> 00:41:41,206
So we send our satellites out,
we observe the radiation...
725
00:41:41,248 --> 00:41:43,666
the symmetrical standing waves.
726
00:41:49,048 --> 00:41:52,717
A new wave of detectors,
gravity wave detectors...
727
00:41:52,760 --> 00:41:54,427
will be launched
into outer space...
728
00:41:54,470 --> 00:41:58,223
in the next decade.
729
00:41:58,265 --> 00:42:00,350
Connected by laser beams...
730
00:42:00,392 --> 00:42:02,894
any shockwave
from the incident of creation...
731
00:42:02,937 --> 00:42:05,855
will jiggle these laser beams...
732
00:42:05,898 --> 00:42:08,274
and we'll be able
to then record...
733
00:42:08,317 --> 00:42:13,738
the vibrations left over
from the Big Bang itself.
734
00:42:13,781 --> 00:42:15,740
That's why I'm confident
that we'll be able...
735
00:42:15,783 --> 00:42:17,909
to probe not just
the Big Bang itself...
736
00:42:17,952 --> 00:42:23,373
but even the pre-Big Bang era
in the coming decades.
737
00:42:23,415 --> 00:42:25,041
The lasers will also detect...
738
00:42:25,084 --> 00:42:27,085
sources of
inflationary energy...
739
00:42:27,127 --> 00:42:29,504
and perhaps determine
the mechanism...
740
00:42:29,547 --> 00:42:31,756
that created the Big Bang.
741
00:42:39,265 --> 00:42:42,559
If we struggle to solve
the greatest mystery of all...
742
00:42:42,601 --> 00:42:47,272
how can we ever hope to really
understand the universe?
743
00:42:47,314 --> 00:42:50,275
Whenever you get an answer
to a question...
744
00:42:50,317 --> 00:42:54,279
it almost always leads
to more questions.
745
00:42:54,321 --> 00:42:57,407
You make progress
and mysteries can get solved...
746
00:42:57,449 --> 00:42:59,409
but then there'll always
be more mysteries.
747
00:43:07,293 --> 00:43:09,460
We are the result...
748
00:43:09,503 --> 00:43:12,297
of the universe attempting
to understand itself.
749
00:43:12,339 --> 00:43:20,054
That's my conception of
our place in the universe.
750
00:43:20,097 --> 00:43:23,016
And so that makes it difficult
to understand...
751
00:43:23,058 --> 00:43:25,518
but nevertheless,
it might be possible.
752
00:43:31,567 --> 00:43:33,359
The universe
is constantly changing.
753
00:43:33,402 --> 00:43:36,487
But the laws,
the laws of physics...
754
00:43:36,530 --> 00:43:38,114
are immutable.
755
00:43:38,157 --> 00:43:39,824
They don't change...
756
00:43:39,867 --> 00:43:43,369
and that gives us hope
that out of all this chaos...
757
00:43:43,412 --> 00:43:45,246
we'll be able to explain...
758
00:43:45,289 --> 00:43:50,793
how it all got here
to begin with.
759
00:43:50,836 --> 00:43:53,254
In our ever-changing
universe...
760
00:43:53,297 --> 00:43:57,300
the unexplained mysteries
will continue to elude us.
761
00:43:57,343 --> 00:43:59,844
But we are edging
ever closer...
762
00:43:59,887 --> 00:44:02,263
to unlocking
the ultimate secrets...
763
00:44:02,306 --> 00:44:07,518
the keys to our past
and the pathways to our future.
764
00:44:07,561 --> 00:44:10,813
While science has made sense
of many things...
765
00:44:10,856 --> 00:44:13,274
there is still plenty
left to be discovered...
766
00:44:13,317 --> 00:44:19,155
about our vast, dark,
and mysterious universe.
60501
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