Had you told people many years ago that the earth was round, they'd have thought you were lying. As far as our forefathers were concerned, they lived on a flat surface and could fall off at any moment. It wasn't until experts could prove and explain how we're all on one giant, spinning ball that people truly believed it.
It's the same with many facts. Some sound like utter rubbish. Others seem too wild to be true. Someone asked, "What scientific fact sounds like complete nonsense until someone explains the maths or physics behind it?" and a bunch of nerds came out to play.
From lesser-known details about the solar system, to explanations on why cumulus clouds float despite weighing around 1.1 million pounds each, here are some of the most interesting responses.
#41
There is no such thing as an absolute present because the notion of "now" is different in every reference frame. For instance an observer watching the solar system from 100 light years away would observe that the current year is 1923. In the same vein there is no such thing as absolute simultaneity. Two events which appear simultaneous in one star system will not appear simultaneous just a few light years over.
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6points
#42
The side of the moon which is facing the earth right now is the same side that always faces the earth and always will be (assuming no outside influence, and that the maths is correct).
Basically the moon is Tidally Locked to the Earth, meaning it’s rate of rotation matches it’s orbital rate around the earth. It’s like if you walked in a circle around your friend but rotated your body to always be facing them square-on.
The moon USED TO spin way faster on its axis, but remember that the moon has an effect on our oceans and causes tides. Mass attracts mass and vice versa, so this acted as friction on the moon’s rotation and caused the moon to rotate more slowly.
Our moon and earth have been at this for so long that the rates are matched and thus tidal locked, HOWEVER the mutual gravitational forces is still slowing both bodies down! The Earth is still spinning faster than the moon is, the moon is just matched to its own orbit around the earth now. So what’s happening is the moon is now slowing down the earth’s rotation too, meaning days on earth are getting longer!
Each century the length of an Earth day gets longer by 1.4-2.4 milliseconds. When the dinosaurs existed a day was only about 23-23.5 hours long depending on the exact year. In about 200 million years our days will be 25 hours long instead, kind of crazy!
Oh- and one last piece of trivia. People often talk about the “light side” of the moon and the “dark side” of the moon, this does NOT mean the same thing as the “near side” of the moon and the “far side” of the moon. The dark and light sides switch as the moon orbits the earth and rotates on its axis, but the near side (which faces earth) and far side (which faces away) are what always stay the same.
Basically the moon is Tidally Locked to the Earth, meaning it’s rate of rotation matches it’s orbital rate around the earth. It’s like if you walked in a circle around your friend but rotated your body to always be facing them square-on.
The moon USED TO spin way faster on its axis, but remember that the moon has an effect on our oceans and causes tides. Mass attracts mass and vice versa, so this acted as friction on the moon’s rotation and caused the moon to rotate more slowly.
Our moon and earth have been at this for so long that the rates are matched and thus tidal locked, HOWEVER the mutual gravitational forces is still slowing both bodies down! The Earth is still spinning faster than the moon is, the moon is just matched to its own orbit around the earth now. So what’s happening is the moon is now slowing down the earth’s rotation too, meaning days on earth are getting longer!
Each century the length of an Earth day gets longer by 1.4-2.4 milliseconds. When the dinosaurs existed a day was only about 23-23.5 hours long depending on the exact year. In about 200 million years our days will be 25 hours long instead, kind of crazy!
Oh- and one last piece of trivia. People often talk about the “light side” of the moon and the “dark side” of the moon, this does NOT mean the same thing as the “near side” of the moon and the “far side” of the moon. The dark and light sides switch as the moon orbits the earth and rotates on its axis, but the near side (which faces earth) and far side (which faces away) are what always stay the same.
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5points
#43
Fractals can have an infinite perimeter length but a finite shape area.
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5points
#44
Adding more lanes to a highway can lead to more congestion, since more people will choose that road over smaller ones. Also, adding a road in a city can also increase congestion, since you increase the number of ways traffic can end up on a specific road.
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5points
#45
Tyrannosaurus rex and Stegosaurus existed further apart in time than Tyrannosaurus rex and us in the current day.
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5points
#46
A piece of paper folded 52 times reaches as tall as the moon.
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4points
#47
I still can't fully wrap my head around it, but Hank Green says it's true and I trust him:
So, I'm a long way away from something, and I want to activate it instantly. INSTANTLY, the speed of light is too slow, and I'm like down on earth and the button or lever or whatever is all the way on the moon.
So I get the bright idea to make a massive pole that can reach from the earth to the moon, thinking obviously the two ends of the solid pole will move simultaneously, so the moment I whack my end, the other end hits the button/switch.
But science tells us nothing can go faster than the speed of light, so obviously it can't be instant across distances. So how fast does the start signal travel from my end of the pole to the moon? Hank says the speed of sound.
So, I'm a long way away from something, and I want to activate it instantly. INSTANTLY, the speed of light is too slow, and I'm like down on earth and the button or lever or whatever is all the way on the moon.
So I get the bright idea to make a massive pole that can reach from the earth to the moon, thinking obviously the two ends of the solid pole will move simultaneously, so the moment I whack my end, the other end hits the button/switch.
But science tells us nothing can go faster than the speed of light, so obviously it can't be instant across distances. So how fast does the start signal travel from my end of the pole to the moon? Hank says the speed of sound.
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4points
#48
There are more strains of virus on Earth than stars in the observable universe.
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4points
#50
It's physically impossible to get a hamster drunk unless you mainline alcohol into their bloodstream. Their metabolism is lightning fast.
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4points
#51
The Monty Hall Problem!
Long story short, you need to pick between three doors, only one of which has a prize behind it (33% of winning). You choose a door, then one of the doors is opened and shown to not contain the prize. Now only two doors are left, the one you chose, and the one you didn't.
Should you stick with your original choice or should you switch?
The answer is that you should switch, because the new choice has a 50% chance of winning, while your original choice only had 33%.
It's counterintuitive, but that's the math!
Long story short, you need to pick between three doors, only one of which has a prize behind it (33% of winning). You choose a door, then one of the doors is opened and shown to not contain the prize. Now only two doors are left, the one you chose, and the one you didn't.
Should you stick with your original choice or should you switch?
The answer is that you should switch, because the new choice has a 50% chance of winning, while your original choice only had 33%.
It's counterintuitive, but that's the math!
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3points
#52
The universe is only about 14 billion years old, but the radius of the observable universe is about 47 billion lightyears.
Hot water really can freeze faster than cold water.
e^pi*i + 1 = 0
Energy isn't actually conserved in modern cosmology, and that's okay because dark energy breaks time translation symmetry.
You can make sail-powered vehicles that travel against the wind faster than the wind.
Hot water really can freeze faster than cold water.
e^pi*i + 1 = 0
Energy isn't actually conserved in modern cosmology, and that's okay because dark energy breaks time translation symmetry.
You can make sail-powered vehicles that travel against the wind faster than the wind.
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3points
#53
Not a mathematician, just an oldGMAT (and LSAT) guy.
The number of atoms in the universe is approximately 10^80
The largest prime number yet to be found is approximately 10^23,000,000
Prime numbers, which follow no real pattern in math, lie at the heart of computer encryption. Oversimplified, a “key” is created by multiplying two crazy-large prime numbers. One of these prime numbers is known only to one side (the user) and the other prime number is known only to the other side (the program).
Because prime numbers have no pattern and can get so large, even today’s most powerful computers are unable to “discover” these two private prime numbers.
Quantum computers will be different. Allegedly, what a current supercomputer can perform in billions of years could take a quantum computer only a few days.
Except that prime numbers are infinite. So who cares? No matter how powerful a computer might be, we can always just generate larger prime numbers, right? Nope!
We have to store those prime numbers somewhere. But the universe only has a finite amount of space and infinity is infinity is infinity. Numbers can become so large that even if they were written in the smallest possible Plank constant form, the universe wouldn’t have enough room to store them.
The Graham number is the best example of this. Something about the number of points necessary on a hypercube in order to guarantee one uniform slice. The number so big the universe doesn’t have enough room to store it.
This is why SNDE is a horrifying acronym: Steal Now Decrypt Later.
The number of atoms in the universe is approximately 10^80
The largest prime number yet to be found is approximately 10^23,000,000
Prime numbers, which follow no real pattern in math, lie at the heart of computer encryption. Oversimplified, a “key” is created by multiplying two crazy-large prime numbers. One of these prime numbers is known only to one side (the user) and the other prime number is known only to the other side (the program).
Because prime numbers have no pattern and can get so large, even today’s most powerful computers are unable to “discover” these two private prime numbers.
Quantum computers will be different. Allegedly, what a current supercomputer can perform in billions of years could take a quantum computer only a few days.
Except that prime numbers are infinite. So who cares? No matter how powerful a computer might be, we can always just generate larger prime numbers, right? Nope!
We have to store those prime numbers somewhere. But the universe only has a finite amount of space and infinity is infinity is infinity. Numbers can become so large that even if they were written in the smallest possible Plank constant form, the universe wouldn’t have enough room to store them.
The Graham number is the best example of this. Something about the number of points necessary on a hypercube in order to guarantee one uniform slice. The number so big the universe doesn’t have enough room to store it.
This is why SNDE is a horrifying acronym: Steal Now Decrypt Later.
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3points
#54
The largest known black hole, Phoenix A, can fit 100 solar systems laid side by side, within itself.
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3points
#55
The colour purple does not exist - as in, there is no single wavelength of light that is purple.
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2points
#57
Here’s a nightmare fuel one for you: We don’t know how general anesthesia works. Like, we know it works, but we don’t know the mechanism that makes it work, if that makes sense.
It’s theorized that it may actually just give you temporary anterograde amnesia. You are unable to form new memories while “under”. You can actually feel everything and are concious, but unable to move. You just don’t remember any of it.
It’s theorized that it may actually just give you temporary anterograde amnesia. You are unable to form new memories while “under”. You can actually feel everything and are concious, but unable to move. You just don’t remember any of it.
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2points
#58
When a single uranium-235 (U-235) atom undergoes fission, it releases approximately 3.2 x 10^-11 joules of energy, enough to power a small LED for a fleeting half-millionth of a second.
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2points
#60
The number of possible legal moves in the game of go (baduk) is larger than the amount of atoms in the observable universe.
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2points