Look around you. Where are you? Where is this
place you are occupying? Somewhere in a room, maybe in a city on a continent on a planet
orbiting a star in a galaxy among billions. But… where is all of that? While
this may feel like a daft question, it turns out that the concept of an absolute
position is something humans made up. In a nutshell, the universe is a big
bag of space that has things in it. If someone removed all these things, the
stars and planets and black holes and dust, there would just be empty space left.
In empty space, the concept of having a position loses all meaning. Empty
space is uniform, the same everywhere. The space we occupy is not like a stage under
our feet. We can't mark specific points, or staple something to spacetime as an
anchor. Without things there is no position. We are really ever only at a position
in relation to something else. Which also means that things we take for granted,
like up and down are actually relative too. Ok, let us fill the universe up with things again and try to find out where you are,
right now. Relative to everything else. Let us start this video at a familiar place
and then get increasingly weird. From your perspective the world is seemingly flat and you
can move in 3 dimensions. It's what physicists call a 'frame of reference' - the perspective
you have of the universe and how you see things moving around you. Where your up and down
is. Your frame of reference is correct. For you – but not for the rest of the universe. Around 5 kilometers from you, where the horizon
begins, the ground noticeably curves away from you. If you could see through the ground,
you’d see people from below or sideways. But they don't fall 'down' off the planet
because gravity doesn't actually pull them down. 'Down' is an illusion of your reference frame. To
earth's reference frame, gravity just pulls in. But for humans there is an up and down because
within our frame of reference that just makes sense. Which is also why we think that the planet
itself has an up and down, north and south. And we made our maps accordingly. But an observer
looking at the solar system might disagree. Our maps make sense to us because we are
used to them, not because they are correct. Ok. So this is step one – your position
on what feels like a flat surface but is actually a sphere. But this sphere is
always moving, never staying in one position. Earth is orbiting a star, the sun
at the center of the solar system. While we usually imagine this as pretty orderly, someone looking at us from the outside
would see something pretty messy. To see this more clearly we’ll exaggerate
all these movements, this is not to scale. First of all, our orbit really is an ellipse,
so we spend half the year sinking a little bit closer to the sun speeding up, and half
the year rising up a bit and slowing down. And the ellipsis itself changes
its shape every 100,000 years too. And in another cycle of 112,000 years, the
ellipse itself is drifting – which at least creates a beautiful shape. In the end, we
get an orbital path that looks like a wobbly circle with wavy edges. And it gets worse, as
the moon now starts to screw things up too. As the moon is a pretty massive thing, it pulls on
earth. Both objects orbit their common center of gravity, that lies around 4700 km off to the
side of Earth’s core. In practice this means that as the moon orbits earth, it is jerking
earth around a bit, enough to make it jiggle. Ok so you are standing on the
surface of a rotating planet, that is jiggling around the sun in an
elliptical orbit that changes a bit every year. But who's to say the earth is right? From the perspective of the sun the plane
of the solar system is arbitrary, it's defined as the plane the earth orbits in
because that is convenient for us. In reality the other planets are just a little
bit inclined with respect to our plane. From their point of view, we're the
ones with a slightly bent orbit. But this is not it – far from it! The solar system
as a whole is orbiting the center of the milky way galaxy. If we look at the milky way, we can
clearly make out a galactic plane in which the solar system orbits the center every 230 million
years. But of course it is not that simple. First of all, the plane of the solar system
is not aligned with the plane of the galaxy. Nothing really is – just like the planets in the
solar system orbit the sun on their own planes, so do all the stars orbiting the galactic center. The
solar system as a whole is tilted about 60 degrees towards the galactic plane, speeding through
space at almost a million kilometers per hour. Someone in the center of the galaxy would see
the orbits of the planets moving through space in a helix shape, which you can
imagine as a corkscrew motion, on the tilted plane of the solar system,
relative to the plane of the galaxy. This orientation in space means that sometimes the planets are sort of in front of the sun
as it orbits around the galactic core. Let us just look at this for a moment
– there is a strange and eerie beauty abouthow our planets and the sun move through
space. Do you feel a bit dizzy? It gets worse. This is still not the whole story because the
mass of the galactic disk is constantly pulling on the solar system too. Like a drunk dolphin, we're
diving down and shooting up hundreds of lightyears through the galactic plane, ten times every
orbit, along arcs thousands of light years long. We haven’t mapped this motion out
completely, as it takes the solar system tens of millions of years to go up and
back once; and, well, humanity is not that old. Let’s look at your relative
position again. On a planet, tilted towards the sun, jiggled around by
the moon. In a solar system tilted towards the galactic plane, moving forward in a helical
shape, diving up and down through the plane. Hm. But where is “up” in a galaxy? At this point
the frame of reference becomes a bit arbitrary and pointless because of the nature of the
universe at this scale. The Milky way is part of a galaxy group that appears to be part of
greater structures like the Laniakea Supercluster, which itself is part of the gigantic Pisces–Cetus
Supercluster Complex and finally a galactic filament that spans hundreds of millions of
lightyears in all directions and orientations. Someone looking right at us from that far
away will only see the End of Greatness. All stuff appears homogeneous, the same
everywhere. Just like with empty space, when everything looks the same, who's to say
anyone's view is better than anyone else's? We have reached the end of our
little exercise in cosmic humility. Let us make the journey backwards again. From
the indescribably large, to the really large, to our galactic home, to our galaxy, to the solar
system diving up and down through the milky way, to the jiggle of existence. And finally,
back to you, right now, watching this video. If this is all a bit much, don’t feel bad.
The scale of the universe is brain crushing and trying to keep track of how everything is
oriented or decide where the best up and down is, is hard. But it doesn't really matter.
Because it doesn't change where you are. You're already in the best spot you could possibly
be – right here, right now. For all you care nothing can stop you from being right at
the center of your own little universe. Perspective really is everything. That is true
for the universe we all inhabit, but even more so within your personal universe. The way your
life will unfold also depends on what you consider possible. Take us at Kurzgesagt: our passion is
to spark curiosity for science and make videos for free. But this is not a great business model so we
began to create our own lines of science posters, calendars and fun kurzgesagt merch - pieces of
Kurzgesagt - that you can take home and touch. And we are doing this with Shopify, who
also were so kind as to sponsor this video – which delighted us because we have
been using their platform for years now. Shopify is an e-commerce platform that
allows you to start and grow your business. And by starting a business, we really do mean
from scratch: if you want to sell your handmade ceramic mugs out of your bedroom today, you can.
But not just that – if you want to scale your one-man show to a sizeable team, then Shopify
has the tools to support you on your journey. Now you just have to get started: go to
shopify.com/kurzgesagt to get a free 14 day trial. If you think that this does not apply to you and
your ideas are too small, we want to encourage you to think again: the first video on this channel
was a university project and Kurzgesagt itself was a creative outlet. Eventually we grew
into a business and the team that is making videos for you today. And all of that just
because we wanted to try out something new. This is exactly the sort of thing
that Shopify is determined to support and you can build your own thing with it. After
all, whetheryour idea is still just a dream or might turn into a plan today is also just a matter
of perspective. Millions of businesses in over 175 countries are currently using Shopify to sell
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DESCRIPTION
Look around you. Where are you? Where is this place you are occupying? Somewhere in a room, maybe in a city on a continent on a planet orbiting a star in a galaxy among billions. But… where is all of that? While this may feel like a daft question, it turns out that the concept of an absolute position is something humans made up.
In a nutshell, the universe is a big bag of space that has things in it. If someone removed all these things, the stars and planets and black holes and dust, there would just be empty space left. In empty space, the concept of having a position loses all meaning. Empty space is uniform, the same everywhere.
SOURCE AND FURTHER READING
https://sites.google.com/view/sources-jiggle-of-existence
Gotta admit I teared up a little at the end there… “it doesn’t really matter — you’re in the best place you could be, right where you are.”
Surprised they didn't mention the Cosmic Microwave Background Radiation doppler shift. It's very clear that the sun is currently moving at 369.82 ± 0.11 km/s in the direction of the constellation Leo relative to the universe's average. All other motions in the video can be anchored to that fact. While position is arbitrary and velocity is relative, any intelligence anywhere in the universe will pick the CMBR as a natural universal frame of reference.
Made me think of Malcolm in the Middle
2:35 So will present a correct map or will you rather continue to scam people with fake maps?
I hate the fact that it's a VSauce rip off.
yay new video
Watched the entire video, awesome as it usually is. Hopefully this channel doesn’t go anytime soon.
So in summary,
The missile knows where it is at all times. It knows this because it knows where it isn't