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Big History Project
Course: Big History Project > Unit 10
Lesson 3: Looking Forward | 10.2- WATCH: A Big History of Everything - H2
- READ: Complexity and the Future
- WATCH: Bill Gates — Visions of the Future
- WATCH: The Deep Future
- READ: Satyendra Nath Bose - Graphic Biography
- READ: Biography of Sylvester James Gates, Jr.
- ACTIVITY: DQ Notebook 10.2
- ACTIVITY: The Future of Our Planet
- ACTIVITY: Threshold Card — Threshold 9 The Future
- Quiz: Looking Forward
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WATCH: The Deep Future
Finally, after what seems like eons and eons, the end is nigh. We're talking not only about the end of Crash Course Big History, but also the end of everything. The end of humanity and the end of the universe.John and Hank Green will teach you about what the future holds for humanity and the universe. Spoiler alert: in the long, long, long, long, long, long term, it doesn't look good. In the short term though, it's not too bad. But don't lose hope, there is an upside. You'll have to watch the video to find out.
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Twitter: https://twitter.com/BigHistoryPro.
Want to join the conversation?
- How old is our milkyway?(1 vote)
- The Milky Way is about 13.6 billion years old, so it formed shortly after the Big Bang, which was around 13.8 billion years ago.(2 votes)
- What is the milkyway(1 vote)
- It's a candy bar... (;(1 vote)
- What is the milk way please(1 vote)
Video transcript
So what have we learned
so far from Crash Course Big History? Well, the universe is big;
it's really big. And it started from nothing. And now a whole lot of nothing
surrounds tiny pockets of something, and one day
the entire universe will return to almost nothing. Our universe may be one of many, just a tiny hole
in a block of Swiss cheese that forms a multiverse
with many other holes entirely beyond our sight
with constants and dimensions and physical laws
stretching away from the mental comprehension of humanity's
most brilliant minds. But in our tiny cosmic bubble forming as if by accident, the physical laws
of the universe and the unequal distribution
of energy arrange themselves in such a way
that in the cosmic blink of 13.8 billion years in a still fairly young cosmos,
we have emerged. Us, with all of our fighting
and reproduction and consumption,
we have been cobbled together from the ashes of dead stars. We have been forged on Earth,
despite the chaos of a molten planet bombarded
from above by every rock
in the nearby solar system. And we have survived and evolved
by the slimmest of margins. Our existence perpetually
balanced on the edge of a knife. I mean, a couple times already
we've almost gone extinct. Some of our obstacles
have been physical, and some have been
of our own making, but from here, many transformations
still await us. Now, I guess
from our perspective, some of these transformations
may be good. Some of them will
definitely be bad, like, you know,
ceasing to exist. But really, it all depends
on your perspective. I mean, no outcome is
absolutely good or bad in the eyes of the universe. The universe is blind. The universe doesn't see. It just is. Oh, I forgot the intro.
Hi, I'm John Green. Welcome toCrash Course
Big History. Today we're talking
about the deep future of life, the universe
and everything. So today we're talking
about the future. Actually we're talking
about several potential futures falling on a spectrum. First, there's the
projected future. This is the business
as usual, where... I predict that the sun
will rise tomorrow and that I will skip breakfast
and go to work. Second, there is... For instance, it could happen
that tomorrow morning I will find time
to eat breakfast, and I'll discover
that it energizes me and improves my productivity and really is the most
important meal of the day. Unlikely, but it could happen according to our current
knowledge of how things work, in this case,
how things work in my kitchen. Third is the... For instance, I may find
a pill that provides me with all the calories and
nutrients I need for the day, and I never have to thinking
about eating or food again. In terms of the universe,
if we were to gain knowledge of, like, what dark energy is
and how it works, we may alter
the current narrative of how it will continue
to evolve. Fourth, the preposterous future
of outlandish predictions. 150 years ago,
the idea of flying to the moon would have seemed preposterous,
but one way to test the limits
of the possible is by going beyond them
into the impossible. A lot of preposterousness
is possible in the next 1,000 years,
or 10,000 or ten million, or even 100 trillion years. So what might happen
in the next 1,000 years? Well, last week, we discussed
how the next century might be pretty rough for us, but let's say that humanity gets through
the 21st century bottleneck, and our collective learning and
complexity continues to grow. Well, then maybe there could be
another great revolution, like another explosion
of complexity as we saw with the dawn
of agriculture or the advent of industry. In the next 1,000 years, we could master hydrogen fusion, the same process
that goes on in the sun, and that would provide us with
a tremendous amount of energy. It would solve most
of our energy problems. Another possible
great revolution is known as transhumanism, like your brain is sort
of a computer. So imagine if you could upload
your consciousness to something plastic or metal
like an actual computer. You know, the thing
about human brains is that they kind of rot. So never mind living
70 or 80 years. Try millions of years. Now, some say that both
of these revolutions might be possible
within our lifetime, or at least within
your lifetime. And they're actively
being pursued by scientists, but we've been promised
a lot of things about the future over the years. I still don't have a jetpack. I find that the Wi-Fi
in airplanes is very slow, and I'm not by nature
a complainer, but my amazing
virtual reality headset makes me feel nauseated. But on the timescale
of 1,000 years, those revolutions
and many others that we haven't thought of,
are perfectly possible if human complexity
continues to rise. Now, that's a big if,
but let's get into bigger ifs, like what about
the next 250,000 years? Well, on that timescale,
the possibility of, like, a super volcano eruption,
like the one at Mount Toba that killed off
almost all humans on Earth, becomes pretty likely. Then when it comes to asteroids, so-called "city killers" hit,
on average, every 100 years, although most just land
in the ocean, and ones big enough to wipe out
most species on Earth, like in the extinction
of the dinosaurs, can potentially land
every few hundred million years. Now, it's possible that
by this point, we could've colonized
some of the moons and planets
of the solar system. It's also possible that we could
have the technology to survive centuries-long
space flights out of our solar system. Especially if we can get
some of that transhumanism, because it would remove the need
to bring along things like water and food, and also we wouldn't have
to be afraid of the immense amounts
of space radiation that destroy humans. Quick question, Stan.
How is there not a band called either Space Radiation
or the Transhumans? Okay, let's zoom out
even further and talk about millions
of years. If Homo sapiens hasn't
been wiped out by some disaster within
the next several million years, our species probably
won't be around anyway, because we'll have evolved
into something else. Like, seven million years
is roughly the amount of time since our species split from our common ancestor
the chimpanzees. And while we do share 98.4%
of our DNA with them, a lot of evolutionary change can
happen in a few million years. This is especially true
when you consider that the human capacity
for genetic engineering may have developed in a lot
of scary and/or awesome ways, further increasing
the pace of change. And when it comes to moving
outside of the solar system, a few million years is actually
a pretty long time. Like presuming that humanity
never finds a way to move faster
than the speed of light, physicists estimate that
on the timescale of five to 50 million years, we could colonize almost
every star system in our galaxy. That shows you the precision of predictive science,
by the way. Five million years
to 50 million years. It's only
a 45 million-year difference. But here's a crazy thing
to consider. If we can't move faster
than the speed of light, we will never get
outside of the Milky Way, because the vast distances
between star systems also mean that human populations
will be separated by thousands of light-years, and when a species
is separated into, you know, different physical pockets
of the universe, it stops being the same species
pretty quickly. I mean, you put turtles
on different islands for a few thousand years
and you get different species. I don't think
that we're gonna, like, hold on to our shared humanity across hundreds of thousands
of light-years. So imagine
a distant future where, like, each star system is seeded
by an ancestor, and then
a few million years later, those cousins look profoundly
different from each other. Wait, like, as different
as Americans look from Canadians or more different? More different, apparently. How can you look more different
than I do from a Canadian? Another thing I'd like you
to consider is humanity's increasing ability
to harness energy. From the firestorm of
the Big Bang to the first stars blinking
into existence to life's active harvesting
of energy to the massive increase
of energy used in the Industrial Revolution... And that's our overarching theme
inBig History. So life on Earth has gotten
pretty good at harnessing the energy that's, like,
within Earth and that comes to Earth
from the sun, right? But maybe a time could come
when humanity or something else like us in the universe
could harness the entire power
of a different planet or a chain of several planets or a galaxy. Then we could harness
many orders of magnitude more energy than we can now, and we know that
is closely associated with rising complexity. But perhaps
I've speculated too much. The thing about futurism is that
the further you look ahead, the more certain things
become again. That's thanks to the beauty
of physics. So let's look again
at the projected future based on our current knowledge. So, what will happen
in the next billion years? In about a billion years,
the sun will have begun to exhaust its fuel
and will start to inflate. Its luminosity will increase, and this means plants on Earth
over the following years will find it harder and harder
to do most forms of photosynthesis and thus sustain complex life
on Earth. The beginning of the end. What will happen in the next three to five billion years? Now the story's starting
to get even more tragic. The sun will get
larger and larger until it boils the surface
of the Earth dry. Once we get
to a surface temperature greater than
100 degrees Celsius, we can be pretty sure that
that's it for life on Earth. So, if anyone human or human-like
is still around, we'll have to leave
our childhood home and move into a dorm room
somewhere else in the galaxy. We won't even be able
to come back home for our moms to do our laundry. How about in the next
200 billion years? As dark energy continues
to accelerate the expansion of the universe
past the speed of light, we will no longer get to see
light from other galaxies. If we were to lose the knowledge of the Big Bang cosmology
that we were taught at the beginning of this series, our galaxy would be all we'd see
or be aware of. We'd revert to the idea
that the universe had no start date,
is static and eternal. The Milky Way would be our
entire universe. That's why a number of
scientists refer to the current age where we can
see evidence for the Big Bang and see other galaxies as the... But, you know, a golden age that lasts hundreds of billions of years
is not so bad. What will happen
in the next 100 trillion years? The last tiny slow-burning star will have flickered out and new ones
will have ceased to form. No new heavy elements will form. All that will be left is
the residue of heavy elements from long-since dead stars, a cosmic graveyard
where the remains of dead stars and planets wander
in the darkness. But let's not stop there. What about in the next trillion
trillion trillion years? More accurately,
ten to the 40 years. That's a one
with 40 zeroes after it. This is an even more
incomprehensible stretch of time than a hundred trillion years, and even more incomprehensible
things will happen. The most likely scenario
is this. Matter will grow feeble
and decay into energy. And remember... Eventually, the universe
will be an empty orb of weak cosmic radiation
with the energy spread out like too little butter
spread over too much bread. This, as far as we can tell, is the end of complexity
as we know it. And then in the next... ...even black holes will
evaporate and the universe's
grand narrative will have more or less
come to an end. After all those transformations
into a great amount of variety and networks
of intricate complexity, all will pass away. All that will remain is
a universe that is very old and very tired. It is the specter of heat death. Okay, so for me, one of
the most comforting thoughts about all existence comes
from science. The idea from the first law
of thermodynamics that matter and energy are
neither created nor destroyed. The building blocks
that make up our bodies have been around since
the beginning of the universe. We have merely changed form,
and after we die, our bodies will return to that inanimate cosmos
from which they sprang. And in that sense,
all life is connected, and also
all life is kind of eternal. Now, of course,
there's still the fear of losing
your particular consciousness, depending on your worldview. Like, I will cease
to be John Green. And from my perspective,
that's not ideal, but we're programmed
to have that fear. If we weren't afraid
of ceasing to exist, we wouldn't be
a very good species. We would have gone extinct
ages ago and none of us ever
would have gotten to be. I don't think
that's either good or bad. It keeps our species going,
and the universe looks on free from any mandate
or obligations or programming, completely free. And what a lot of us overlook is that we are not just observers
of the universe. We are the universe. We don't exist
outside of the universe. We are indivisible from it. We are made of the same stuff, and in all
of our transformations over billions of years,
from star stuff to single cells to students
to one degree or another, at every stage,
we've shared in that freedom
of transformation to flow endlessly from one form
to another. And maybe we won't survive
as individuals. Maybe we won't survive
as a species, but we will continue
into the deep future. We are a tiny part
of the universe, but we are part of it, and from so simple a beginning in ways most beautiful
and most wonderful, we the universe have been and are being evolved. That ability--
in fact, necessity-- to change, is your birthright acquired
at your original birth 13.8 billion years ago, and it can never be taken away. It can never be destroyed. Thanks for watching
Crash Course Big History. And as we say in my hometown,
don't forget to be awesome.