hello my name is Michael and welcome to
dawn the first and only YouTube channel
made by of and for teens who like cooking
today we're gonna be talking about
babies babies are being born all the
time in some countries they're born more
often than others this website neil dot
fun slash a baby map lights up each
country on earth at the same rate that
babies are born in that country so as
you can see India and China light up a
lot if you watch long enough you'll get
a little UK blip that's a baby being
born I mean not like we don't it's on an
exact baby but the country's light up at
about the same rate as the country's
birth rate so you can really get a sense
of where people are being born you know
to be honest humans are like one of my
top ten favorite animals let's keep
talking about humans and how many of
them there are with population
bracketology this website sets up a
bracket of cities and then it's your job
to figure out who would win in a battle
of who's got the largest population I'm
gonna change it from metro area to state
population make a new game uh some of
these states have a by weeks but let me
see here between North Dakota and
Illinois Illinois clearly is gonna win
it's got big cities it's got Chicago oh
when you click Illinois there you go now
between Idaho and Vermont Vermont is not
very populated but Idaho I'm gonna go
with Idaho sure close one all right
between New Mexico and Massachusetts
Massachusetts definitely has more people
and between Idaho and Massachusetts
obviously Massachusetts does but between
Illinois and Massachusetts that Chicago
versus Boston and that Boston metro area
is quite expansive but I'm gonna go with
Illinois Bob Chicago is like the number
three most populated city I will keep
playing this on my own time so I don't
waste yours we need to move on to outer
space specifically people who have been
there travels in time and space allows
you to look at astronauts from all over
the world from every country even the
commercial and tourist astronauts right
now I have my axes built so that I've
got the length of trip on the vertical
axis the further down we go
the longer the person was in space and
the horizontal axis is when their first
launch occurred so if we go to the very
furthest dot and click on it
yuri gagarin first human being in space
he only spent point zero eight days in
space so he's well didn't have a very
long trip if we go to more recent
launches you'll see that some of these
dots have white circles around them
those represent people who are currently
in space astronaut scott tingle what's
up
you obviously eat little bit the
astronaut ok astronauts don't just
travel through space they also travel
through time like we just did my beards
longer sure it's different
continuity isn't really a priority here
at Vsauce headquarters but what is a
priority is learning let's take a look
at this graph and change the horizontal
axis to represent time dilation there is
clearly some function that defines how
you move through time when you are
moving through space and where you're
moving through space check this out
the world record for longest time in
orbit is held by cosmonaut padalka who
spent 878 point 48 days flying very
quickly around the earth and because of
that padalka is about well more than 25
milliseconds younger than he would have
been if he'd stayed here on earth that's
because of time dilation now when you're
in orbit time moves for you at a
different rate because of two different
effects special relativity and general
relativity if you want to learn more
about these I highly recommend these
books
first of all Martin Gardner's relativity
simply explained a fantastic but my
favorite book that I read in all of 2017
was Lewis Carroll Epstein's relativity
visualized just phenomenal but if you
want to get even deeper you can go a lot
less wrong than getting the Taylor
wheeler spacetime physics book just
unbelievable explanations we've also got
videos linked down below where you can
learn more but the gist of it is this
when you are orbiting around the earth
you are moving faster than people who
are just still down on earth at rest
relative to you and that means that time
moves more slowly for you a person at
rest down on earth if they could take a
telescope and look at your watch would
literally see your watch moving more
slowly you would be aging more slowly
you would be reaching your date of death
slower but also the higher up you go the
weaker the gravitational field around
you will be and that will cause time to
go faster for you
these two effects combined into this
blue line that we see here this red line
represents time dilation due to orbital
speed and as you can see the larger your
orbital altitude is the less quickly you
have to move to not crash into Earth and
so the smaller the effect is now this
green line represents the general
relativity effects the gravity well
getting weaker and as it does you move
through time faster and faster and
faster their combined effect is this
blue line labeled net orbital time gain
now astronauts in the National Space
Station are at about you know this
altitude a few hundred kilometers and
that puts them on the blue line down
here meaning they experience less time
than us down on earth
that's why padalka is about maybe 30
milliseconds younger than he would have
been had he not gone into orbit if you'd
like to see how you have been moving
through time time orbit will help a lot
the University of Surrey created this
app and it takes information about your
altitude and motion to compare how you
have moved through time since installing
the app compared to someone who has
spent that entire time motionless at sea
level fun fact about 3200 kilometers
above Earth's surface a little shy of
10,000 kilometers away from Earth's
center both effects exactly cancel out
and no time dilation is experienced
relative to someone at rest down on
earth anywho I'm sure you have a lot of
questions for instance Michael that's
cool but what I don't understand is how
long can a zucchini grow I'm glad you
asked because the world record for
longest zucchini was set by giovanni
battista Scozzafava of Niagara Falls he
grew Sukie knee two point five two
meters in length it's just phenomenal
but it's actually not that weird
zucchinis like to grow big they just
don't taste
great when they're large ideally
zucchinis are picked when they're young
no more than 12 inches long so if you're
taking notes don't forget that one I
also go back to Lightspeed when you're
traveling really quickly all kinds of
weird relativistic effects occur okay
time dilation happens obviously but also
measured whips change here's a
relativistic car now I can use this
slider here to make the cars velocity
slower or faster I can speed it up and
notice that as I speed it up the car
appears to contract and become thinner
and thinner and thinner until at the
speed of light boom it is well it
doesn't have any measurable dimension in
its direction of travel we've heard this
before and I've talked about it before
in episodes about whether the earth is
flat or not to a particle traveling near
the speed of light the earth would be
measurably flat like a disc but would it
appear to be a flat disc no because of
an optical illusion known as a Tyrell
rotation here's an example from
Wikipedia of what that looks like
I think this animation is brilliant so
on the right we have the actual visual
appearance of a cube flying by at some
proportion of the speed of light and on
the Left we have the contraction the
actual width of it that we would measure
but notice that at 99% the speed of
light it almost is completely rotated so
that we see the other side of it here's
a way to visualize what a Torrell
rotation is and why it happens here's a
cube now let's imagine that this cube is
just moving right past you at some point
it's gonna be right in front of you and
then it's gonna move away now normally
it would look like this it's not moving
very near light speed you can't see the
back of the cube I mean you can because
this one doesn't have any opaque sides
but the point is that material over here
isn't reflecting light to your eyeballs
we can imagine that this green stick is
a ray of light any light coming from
this back edge right towards you that's
getting blocked by the fact that the
cube or the shape whatever shape it is
might be opaque but if this stick
represents how far light travels in a
second and it's got to travel like this
to
to your eye if the object is moving near
the speed of light it might be able to
move out of the way of that beam of
light and not block it so it will reach
you you'll see the back of the object as
if it is actually rotated so an object
traveling near the speed of light will
appear to rotate like that it's only its
appearance it won't actually be rotated
and if you tried to measure it you would
find that its length had contracted
let's watch a video of this effect space
time travel org has a great one and what
you see is a bunch of dice and they're
all in a row but then above them a die
is gonna fly by I think actually a few
died known as dice will fly by in the
same orientation but they won't appear
to be in the same orientation here they
come
all right not looking too weird yet but
as you'll see the closer they get to us
the more rotated they are until boom
right there we can actually see the back
of the cube even though the back is not
facing towards us this relativistic
effect is called a Terrell rotation and
I love it when it comes to relativistic
effects who can forget red shifting and
blue shifting of electromagnetic
radiation not us right and also not
velocity Raptor in this game the speed
of light is much much much slower so the
normal speed of Velociraptor can move at
is quite close to it so relativistic
effects occur now here's the level and
what I need to do is get to this yellow
exit door
but wait these bullets are kind of close
together I should probably be able to
fit through them let me start moving my
velocity will change oh and look the
entire game level warps according to how
length changes which means if I go up
the bullets get closer together I can
spread them out by moving down now I've
got room great whoa whoa whoa whoa okay
don't you don't to fall in the water if
you ever want to center yourself on your
character I think you press C yeah okay
there you go I find this interesting but
not nearly as helpful press C again to
go back also notice that my velocity
it's like I'm playing asteroids if I
stop pushing the key
moving at the same velocity but spacebar
will freeze yourself
let's save your life many times now
let's look at these keys in order for me
to open up this lock I need all of the
keys to have the same color which means
I need to find the velocity that
redshifts and blueshifts them so that
they match now remember velocity is a
vector so there's also a direction to it
so I don't just need to have the right
speed I need to be moving at the right
speed in the right direction
all right I'm able to get these two near
in color but how do i okay for that one
I have to move left and right I think
now I'm getting it really to purple oh
wait that looked but I want to move
towards the bullets all right so moving
to the right is the opposite of what I
want to do let's see what I can come on
change color yes nice and that's how you
do it when you are an expert at the ways
of the universe I'm gonna leave you with
well honestly a bit of motivation we've
all heard of the company Arm and Hammer
right they were founded 151 years ago
the brand was in use about 31 years
before the birth of a man named Armand
Hammer yeah no relation he had nothing
to do with founding the company was a
named after him but as you can imagine
good old mr. hammer
Armand to those who were familiar with
him got constantly teased for having a
name that sounded like the brand Arm and
Hammer so what did he do well when he
got older got enough money together to
buy enough stock in the parent company
of Armand Hammer to become a part owner
that's right so Armand Hammer became a
board member of Arm and Hammer so my
question for you is this what are you
doing today that will be strange enough
that one day it might be discussed on
Daum
stay curious stay hungry be sure to
pre-heat your oven and as always thanks
for cooking Bon Appetit
