- From my personal experience,
anything you wanna know, this man right here especially
when it comes to science has the answer, okay. - Well, I have an answer. Whether or not it's the answer,
that's to be determined. - Please, you're ruining
what I believe in, okay. - I don't wanna dismantle
your belief system-- - Yes, exactly. My whole world is crumbling. I need to believe in you, man. All right. (light music) - Tides are widely misunderstood. - Okay. - All right, the next thing I say may be mind blowing to you, okay. - Okay. - The tide doesn't
actually come in and out. (exploding) (laughing) What happens is there is a
bulge of water, two of them, on opposite sides of the Earth caused by the sun and the moon, and Earth turns inside that bulge. So, when we say the water
rises and falls tidally, what's happening is we are
rotating into the bulge and then out of the bulge. - So, the bulge is already there. - It's already there. - And all we do is pass
through the bulge-- - Pass through and the water
gets high and it gets low. So, we're stuck with language
from our own perspective rather than language of
what's actually happening. It's simpler that way to say
the water goes in and out. It's simpler to say the sun
set, rather than Earth rotated such that our angle of
view on this stationary sun fell below our local horizon. - Right, yeah, sunset is far more poetic. - Yeah, you go to the sunset
tables to look this us. - Yeah, 'cause you can't say
to a girl, hey, how'd you like to go and watch the angular
momentum of the Earth cause the sun to disappear
behind a horizon? - Hello, where'd you go? (laughing) Let's look at just the Earth and the moon for the moment, okay. - Many people think the
moon is what causes it. - No, the moon is two-thirds
of the tides, okay. The sun is another
two-thirds, three-quarters. It depends on the distance. The sun has its own tides on the Earth. - Oh snap. - Wait, in fact, the tides
that the moon raises on Earth are the same no matter the phase. - Okay, no matter the phase of the moon, which there are some people believe that when you have a
full moon, what you have is a higher tide because
you have a fuller moon. - You do have a higher tide. - Oh snap. - But the tide that the
moon raises on the Earth is basically the same no matter its phase. - [Chuck] No matter its phase. - [Neil] What happens at full
moon is that the sun's tides add to the moon's tides precisely. - Oh snap, we talking about
a tide assist from the sun-- - A tide assist.
Oh. - A tide assist, and so that's why-- - And that coincides with the full moon. - Coincides with the full
moon, 'cause a full moon, you got the moon here, Earth and the sun. Everybody lines up.
- That's what it is. In fact, we have a word for
that, that has the most number of letters when scripted dip below the line.
- Okay. I know that's a weird record to hold. The word is syzygy. So, syzygy is when three or more objects come into alignment cosmically. So, you have the moon, the Earth. The moon will have the same
tide it would at any time, but now it lines up with the sun. They add together, you
get the highest tides at full moon and new moon. So, now I ask you when would
you get the lowest tides? - When the sun is not lined up. (laughing) - Okay, let me quantify that. So, when the sun is at 90 degrees, the sun is pulling this way and
the moon is pulling that way and the two waves basically cancel. They try to cancel one another,
so you have the lowest tide. It's called the neap tide. - The neap? - Neap. - Neap tide, see look at this. It's not the moon. It was the sun all along. - It was the sun all the time. - I see, and you think because-- - Wait, wait, so when people say I feel the extra tidal forces
from the moon when it's full, it's just bullshit. - Oh. - So, I just wanna clear that up. Okay, so I haven't explained tides yet. Let me take two minutes to explain that. - Holy crap, that was just
about the moon and the sun and the fact that the bulge. So, that's what we have right now. - Right, so watch what happens. - Go ahead, go for it. - So, and let's just look
at Earth and the moon for the moment. The side of the Earth
that's closest to the moon feels a stronger
gravitational pull of the moon than the side of the Earth
that's farthest away. The closer you are to a source of gravity, the stronger is that force. And that's true for
everything, no matter what. - [Chuck] So, the moon is always exerting a gravitational pull on the Earth. - On the Earth, yes and
there's a difference in the gravitational pull
from one side to the other. Because there is a difference, it means it's pulling
this harder than that. If you do that, you end up stretching. So, the water stretches along the line that the moon's tidal forces are pulling. - Gotcha. - Okay, it's a stretching force. - Right.
- All right. - By the way, we gonna
call that Earth yoga. (laughing) Yes, and now, downward dog. - So, it does that for anything. Water happens to be more
responsive to this force 'cause it's liquid, but
it also raises tides on the solid Earth. But you don't see that
happen and it's much smaller. And so, but it does it
basically for everything. And so, that's how you get the tides. And so, that bulge is always there, but the sun is messing with it. So, as the moon orbits the
Earth and the tidal bulge-- - The tidal bulge is moving with-- - Is moving with the moon and the sun is-- - Exerting its forces simultaneously. - Simultaneously and this
either lines up or it doesn't. - Wow. - Okay, how much brain
you got left to get? - I don't know, man. We about this... - Okay, so now, watch. - We were only working
with this to begin with. Now, we down to about this. - Okay, so watch what happens. - Go ahead. - So, it turns out we are rotating faster than the time it takes the
moon to go around the Earth. So, a day is shorter than a month. All right, so we are actually
if you the viewer are the moon and you're trying to raise this bulge, I'm dragging the bulge ahead of you because I'm rotating faster. - That's right. - Okay, so the bulge is not
actually exactly aligned. - No, it's over here. - It's like that way, it's that angle. - And you're pulling-- - So, now watch. So, it's because I'm rotating. So, now watch. So, the moon is actually
tugging on that bulge trying to line it back up. - Right. - And it does that against
the wishes of our rotation. So, the tidal bulge because of the moon is slowing down the rotation of the Earth. - So, are you telling me-- - That's why we have leap seconds. - There you go. - So, the tides are not only responsible for what we perceive as
water going in and out. It's responsible for the slowing down of the rotation of the Earth. And the Earth has been slowing down ever since the moon has existed. And we know this because
there are mollusks that have certain features
in their physical body that attract to the phases of the moon. - Really? - Yes, okay. So, attracted to how when
they're stuck on the ground versus when the tide comes and gets them. There's a record of the
cyclings of the tides. Now, watch. We also have other evidence for how many of those cyclings occur
in a calendar year. - Right. - And back then, there were more of them, which meant that Earth
rotated faster back then. Yes, so the moon has been
slowing us down ever since. - Or the Earth is just
getting really tired. - And then there are people say if the moon affects the water
and the water's made of water and we're mostly water, well
doesn't the moon affect us? 'Cause we're 80, 70% water. It's a natural thing to think about. - Which is why people
say that people act weird during a full moon. - Yeah, even though the
moon's tides are not stronger. - It's really the sun.
- It's really the sun. See, full circle, baby. Just like Earth. - But you wanna explain lunatics. They're really sunatics. - That's right, solartics. - Solartics, way better. - That's what they would be. - Yeah, you a solartic. - You a solartic. - [Neil] So, here's the thing, the moon creates a tidal
force across your skull. - [Chuck] I did not know that. - [Neil] Yes, across anything. This side of your head
is closer to the moon than this side of your head. But we can calculate what
that difference in gravity is across your head. It's not very much. - Damn man, why you gotta do that to me? (laughing) - 'Cause you got a little head. So, you can calculate how much that is and then you can compare
it to other things that are operating on your head. Like, you go to sleep, there's
a pillow sitting right here. The weight of the pillow
to distort your skull is about a trillion times
stronger than the tidal force of the moon's gravity across your skull. But no one creates whole
mystical predictions about-- - About what your pillow's going to do. - What brand of pillow
you slept with last night. Yeah, so there are very strong
ways you can demonstrate that really there's no effect on people other than the affect you
think it's supposed to have. You come out of the bar
at two in the morning, full moon is up, oh, it's a full moon. I'm gonna act crazy.
- I'm going crazy. - It has nothing to do with
all the Jack Daniels in me. (laughing) That's very cool. - Tides are why you rip,
why you get shredded as you fall into a black hole. The spaghettification of
falling into a black hole is all because of tides. You fall in feet first, a
black hole is small enough so that your height is
gonna make a difference as you fall in. The gravity at your feet begins to greatly outstrip the
gravity at your head. Right now, your feet are
more attracted to the Earth than your head is. But you're six feet tall, that's small compared to the radius of the Earth. A black hole is small. And so, when you come
down near a black hole, your height matters relative
to the size of a black hole. So, this difference in
force grows and grows until it becomes greater
than the intermolecular force that holds your flesh together. And then you end up snapping in two, likely at the base of the spine. - Oh God, that feels good. - Well, initially, you feel good. You say, oh, I like stretching. Who doesn't like a good stretch? And then you would say,
okay, I had enough. (popping)
Pop. (laughing) Now, there's two of you going
down and those two segments feel the tidal force and
then they snap into two. You go from one to two
to four to eight to 16 as you bifurcate as a stream of atoms all the way down to the cosmic abyss. - That is why I am going into
the black hole cannonball. - Actually, I tried to think this through. If you sort of rotate rotisserie style, then it can't focus on
one way to stretch you. So, yeah, you might be able
to get a little further in. - In a cannonball. - In a rotating cannonball. - Okay, cool. - My summative reflections on
this time we've had together is that--
- I enjoyed it, too. Where ever in the universe you
find gravity, you find tides. - Nice. All right, you can see
that we're just starting to dip our toes into the
surface of the science of tides. And if you're interested in
learning more about I don't know gravity's effects on pretty
much everything or how physics affects our everyday lives
or the scientific phenomena of the moon and what it doesn't cause. Hey, whether you're a science enthusiast or an astrophysicist or a professional or a lifelong learner, Brilliant
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word 'cause you always say keep doing what? - Keep looking up. (light music)
My mom worked on a psychiatric office for 14 years. She definitely confirmed this. Any time around the full or new moon things got, well, crazy.
Yea hospital worker with a elementary teacher wife here. Can confirm.