humans can survive in this universe as long as we have an energy source unfortunately
the universe will die it will happen slowly over many billions of years but it will happen
that's not true we actually don't know what's going to happen in the far future we actually
don't know we can extrapolate a head you know and just assume that if things keep going the
way they're going some suspect things will change but we have no idea we and we can't know for sure
on a universal time scale stars like our sun will be gone in no time luckily there are places about
four and a half billion years it is that will exist practically forever from a human perspective
the corpses of dead stars white dwarfs they could be Humanity's last home right before the
death of the universe what are these strange things and what happens when they finally die
how long stars live varies drastically depending on how massive they are that
Thor's hammer welcome workzie for example really massive stars burn hot and fast dying violently
in Supernova a few million years after birth but they're the exception 97 of All Stars will end
their existence as white dwarfs there are two ways this can happen small Stars so-called red
dwarfs burn out over trillions of years until they eventually quietly turn into white dwarfs
medium-sized stars like our sun are more interesting imagine the Sun as a huge pressure
cooker that fuses hydrogen into helium I think it's all pretty interesting but yeah red doors
I think are actually particularly interesting as well it's called through its gravity go check out
our Red Door video right the fusion of elements releases extreme amounts of energy that pushes
outwards and stabilizes the star keeping it in a delicate balance when the sun is old the hydrogen
in the core is exhausted and the sun oh we're getting into some Stellar physics for this one
our black dwarfs theoretical yes because the universe is not old enough for any of
them to exist so we and not only that like even if there were some out there
which there shouldn't be according to our current understanding we wouldn't be able to detect them
so that's another problem right Brown Dwarfs uh you know another thing that's we have detected
a few but they're notoriously aren't we'll begin to burn helium into heavier elements
while doing so it will shed its outer layers when this process is over more than half of the Sun's
mass will be lost into space as a spectacular planetary nebula millions of kilometers across
it's a bit of a weird name because you're like what does this have to do with the planet well
all this stuff actually is what you know can then coalesce into planets in the future so it's like
uh it's like an energy cycle on Earth you know how things die seeps into the ground and then stuff
grows out of that and there's all these Cycles well this when when stars die it's like recycling
and a lot of the stuff you're made of actually comes from stuff like this and exploding stars
like uh and then it gets even weirder you know you've probably heard that you're made of star
stuff right everyone knows this but it's so intriguing to think that you know like your your
left hand it's my right hand and your left hand um you know you might come from different Stars
freaking nuts and uh all the heavy elements in your body come from exploding Stars what remains
will be its former core a white dwarf is born a star corpse while its former self was about 100
times its diameter now it's only about as big as Earth but still with about half of its former Mass
this means it's extremely dense a teaspoon of white dwarf is about as massive as a car
surface gravity is over one hundred thousand times higher than Earth's
if you tried to land on it you'd immediately be compressed into a steaming puddle
life around a white dwarf is very unlikely but possible most of them that exist now
were former stars that well died which probably ruined any planets they once had
but that's not all since they are so small the planet would need to orbit them about 75
times closer than Earth is to the Sun to have liquid water this prop that brings into play
other problems you know the white dwarfs which you know we study them but they could be doing
things which make you know the planets that have to be close actually you know problematic for for
atmospheres to be stable for life to exist on them so who knows proximity has up and
downsides for one it would tidally lock the planet giving it a permanent day and permanent night
at the edges of these day and night zones life could be possible but white dwarfs have a very
stable energy output so they might actually be safer to live around than many red Dwarfs this
is still speculation at this point we've talked about in the red dwarf video how temperamental
these things are and they actually flare more than our style which is you know an average
sort of star very we live in a very average system um but anyway but if we could find a white dwarf
with the right conditions to settle around we could have a home for many billions of years
but why do they shine so much longer than other star types white dwarfs are very very hot up to
40 times hotter than our sun ranking among the hottest objects in the universe but they are not
incredibly active all the heat inside of them is trapped and has nowhere to go only on its outer
layer you've also really got to keep in mind guys a lot of this stuff is you know Stellar physics is
cool and everything but we don't understand a lot of it not to the degree that some people seem to
think like our star for instance it's got you know all sorts of weird stuff going on which we don't
understand for instance it's magnetic field we don't understand it we also know it has this weird
11 year cycle in which the poles flip the north becomes the South and South becomes the North Pole
and it's got all heaps of other weird things we don't we can't explain this and so you
know talking about white dwarfs and other types of stars it gets even worse so just keep this
in mind you know I don't think these videos always do a particularly good job at sort of
you know demonstrating our ignorance just wanted to say you should come get my VPN it's out now
the beta should be out now when you're watching this video it's not out actually right now for
chat I'm just finishing off everything and so yeah come get it you can use it for free I think we're
changing that so I'll tell you guys about that and basically yeah it's got post Quantum cryptographic
algorithms and I can protect you from powerful quantum computers and that'll be important going
forward and I created this who come support the channel yeah can his Escape into space
but space is mostly empty so heat can't be transferred by conduction the only way energy
can escape is by radiation this is so inefficient that white dwarves will take trillions of years
to cool down which may make them Humanity's last Refuge they might be the last sources of
light and energy in a dying universe according to some estimates white dwarfs might shine as
long as 100 billion billion years 10 billion times longer than the universe has existed
it's me right now why did the pole switch we don't know there's lots of ideas and
theories but we really don't know so far into the future that no regular Stars Will Shine Anymore
galaxies will have evaporated and only then will the first white dwarf turn into the first black
dwarf let me rewind a little bit because I was reading the comments are you related to
Chris Hemsworth yeah he's actually my cousin but that's all theoretical what can be wrong
this stuff that he that goes the exact same so far that no regular Stars Will Shine Anymore
galaxies will have evaporated and only then will the first white dwarf turn into the first black
I don't think it's correct to say galaxies will evaporate because that's actually
not going to happen um like you know there's a supermassive black hole at
the center of galaxies that's not what's holding them together though what holds
them together like uh most of the mass is actually from the Dark Matter Halo that's
not going anywhere we don't it only interacts gravitationally so we don't understand how it
would how it interacts if it even does by the other forces and um so you know galaxies will
still be somewhat mostly of what they are you'll still have that black hole stuck in the right in
the middle of the gravitational potential of the big that big uh Halo um so you know what I
mean they're not going to just evaporate they'll be very different very very different and they
will eventually be dark black dwarf when this happens The Last Hope For Life will die off
black dwarfs will be it don't know that that might not be true we could um sit around a black hole
have a little campfire it could be ways to get energy from black holes and um black holes will
actually last even much longer theoretically so this might not be the end and then beyond that
it's also important to keep in mind there could be other ways of getting energy from
from the vacuum you know you might have heard of theoretical things called like the Zero Point
Energy we're not going to talk about that now you go watch the quantum phone video I think we
talk about it in there but so yes there could be other ways there's Dark Energy there's dark
matter who knows if we're going to be able to if it's possible to sort of extract energy from those
things because they you know they have mass and energy so inactive spheres with no energy left to
give still massive enough to kill you if you get too close so cold that they'll be near the coldest
possible temperature in the universe so dark that they are practically invisible the universe will
enter its last stage heat death which will leave the universe unrecognizable should the universe
continue to do what it's currently doing this is what we think is going to happen an absolutely
dark and cold graveyard with black holes and black dwarfs scattered over trillions of light years
we don't know for sure what will happen with black dwarfs in the end if the proton one of the
fundamental parts of atoms has a limited lifespan black dwarfs will slowly evaporate
over many trillions of years if the proton does not Decay black dwarfs will probably turn into
spheres of pure iron via Quantum tunneling over a time span so obscenely gigantic that
calling it forever is okay these iron spheres will then I don't agree if timed infinite then
it's hardly the time scales we're talking here for the black dwarfs is hardly even close to
infinite so travel completely alone through a dark universe nothing new will happen anymore forever
while this may sound kind of big assumptions all over the place
dark this is so far away that for our purposes today it might as well not happen at all it
doesn't matter what happens in a billion trillion years right now doesn't it it might
we happen to exist at an excellent time able to be in awe about a universe filled
with endless stars and light and planets and enough time to visit them one day
our music is finally available on can't argue with that but anyway
so that's that video guys I enjoyed that