this post was submitted on 20 Jan 2025
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[–] Didros@beehaw.org 3 points 3 hours ago

The one I say themost is probably that there are 10 times as many germ cells in your body as human cells, but due to their size it is only around 8 pounds of your weight.

But the one I love the most is that there are more unique ways to shuffle a deck of cards than there are grains of sand on Earth.

[–] OsrsNeedsF2P@lemmy.ml 6 points 4 hours ago (1 children)

There are more atoms in a single molecule of water than there are stars in the solar system

[–] qjkxbmwvz@startrek.website 3 points 2 hours ago

That's...pretty believable.

[–] hOrni@lemmy.world 2 points 4 hours ago (1 children)

Not really favourite, but definitely most unbelievable: They elected Donald Trump for president in the US. Twice.

[–] OsrsNeedsF2P@lemmy.ml 1 points 4 hours ago
[–] AnonomousWolf@lemmy.world 9 points 13 hours ago

Sharks are older than trees

[–] ace_garp@lemmy.world 37 points 1 day ago

Butterflies can remember things from their time as a caterpillar.

These memories are retained after going through metamorphosis, the breakdown of their caterpillar form into a cellular soup (or partial soup).

Details here

https://theconversation.com/despite-metamorphosis-moths-hold-on-to-memories-from-their-days-as-a-caterpillar-29859

[–] Telodzrum@lemmy.world 24 points 1 day ago (1 children)

The fax machine predates the (first) American Civil War.

[–] crimsonpoodle@pawb.social 9 points 13 hours ago (1 children)

Dude did you need the “(first)”? I’m really trying to be optimistic this morning x.x

[–] Telodzrum@lemmy.world 3 points 12 hours ago

Sorry, dark humor is the only kind I have left.

[–] golden_zealot@lemmy.ml 28 points 1 day ago* (last edited 1 day ago) (1 children)

There are more trees on earth by far than there are stars in the galaxy.

[–] jacksilver@lemmy.world 19 points 1 day ago (1 children)

I had to looks this one up, but missed the "galaxy" vs "universe". There are an estimated 3 trillion trees, 100-400 billion stars in the milky way galaxy, but potentially 1 septilliom stars in the universe.

However all three of these are estimates, so who actually knows.

[–] mipadaitu@lemmy.world 7 points 1 day ago (1 children)

I'm not sure where these numbers are from, but my guess is that you mean the Observable Universe, which is just the part of the universe that we can see.

We don't know how big the full universe is, it could be infinite with an infinite number of stars.

[–] jacksilver@lemmy.world 4 points 1 day ago

Just some quick Google searches so not sure how reputable, but didn't feel like copying random links.

But yeah, that's why I called them out as estimates as I suspect there is a lot of room for error in those numbers.

[–] balsoft@lemmy.ml 24 points 1 day ago* (last edited 1 day ago) (2 children)

That British guy, Jack "That guy who fought World War 2 with a claymore and bagpipes" Churchill, was also an early pioneer of surfing.

[–] PM_Your_Nudes_Please@lemmy.world 10 points 1 day ago (3 children)

The electric field one is also interesting, because the cable length doesn’t actually determine how long it takes to turn on. All that matters is the distance between the power source and the device. Electricity travels at the speed of light, which means we can measure how long it should take to travel down the wire.

But let’s say you have a 1 light year long power cable, made out of a perfect conductor (so we don’t need to worry about power loss from things like wire resistance or heat). Then you set the power source right next to the device and turn it on. The logical person may say that the device would take a full year to turn on, because the cable is one light year long. Others may say that it will take two light years to turn on; Long enough for the electricity to make a full circuit down the cable and back to the power source again.

But instead, the device turns on (nearly) instantly. Because the wire isn’t actually what causes the device to turn on. The device turns on because of an EM field between itself and the power source. The wire is simply facilitating the creation of that field. The only thing that matters is the distance between the source of power and the device. That distance, divided by the speed of light, is how long the device will take to turn on. If the device was a full light year away from the power source, it would take a full year to turn on. But since the device is sitting right next to the power source, it turns on right away.

[–] balsoft@lemmy.ml 8 points 23 hours ago* (last edited 22 hours ago)

But instead, the device turns on (nearly) instantly. Because the wire isn’t actually what causes the device to turn on

That's not exactly true. In this case, the energy transmission would go like this: (change of electric field in the little bit of wire next to the power source) -> (change of magnetic field in the air between the wires) -> (change of electric field in the wire next to the load). This limits the amount of energy transmitted significantly and incurs a lot of losses, meaning if you had something like a lamp plugged in it would start glowing extremely dimly at first (think about how some cheap LED lights keep glowing even with the switch off - it's similar, albeit it happens due to inter-wire capacitance and not induction). It would then slowly ramp up to full power over a course of a year.

Here's a video from the same person about it: https://www.youtube.com/watch?v=2Vrhk5OjBP8 (although I haven't watched this yet)

Edit: after watching the video, I think I was actually wrong in a couple of my assumptions. First of all, it looks like the reason for the initial energy transmission is wire capacitance and not induction, so (electric field in wire) -> (electric field in air) -> (electric field in wire, in the "opposite direction", but because the wire goes back and forth it's the same current direction). This means that my LED example is even more potent. And the second one is that because it's capacitance and not induction, this means that there's no slow ramp-up, it just makes the light glow very dimly all the way until the electric field makes it through the wire, and then it ramps up very quickly.

[–] bountygiver@lemmy.ml 3 points 1 day ago

wait so if you have another person travel to the other end of the wire, and do a time sync with consideration of time dilation to tell them to cut the wire 1hr after you turn on the power, will the device turn off after 1 year since it wouldn't "know" the wire is cut until a year has passed?

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[–] HiddenLayer555@lemmy.ml 17 points 1 day ago (1 children)

Printer ink costs more per milliliter than human blood.

[–] qjkxbmwvz@startrek.website 1 points 2 hours ago

"Wow you signed the document in blood, you must be really hardcore."

"No I'm just cheap."

[–] randombullet@programming.dev 56 points 1 day ago (7 children)

Consider a dam that is 10m tall

Then consider the height of water behind that dam is 5m tall.

Does the dam need to be built stronger if the water behind it is 1 km long?

How about only 500m?

How about 1m?

The answer is, it doesn't matter. Water exerts pressure equally regardless of how much water is behind it.

Therefore a graduated cylinder that is 10m tall needs to resist the same amount of force as a dam 10m tall regardless of how much water is behind the dam. Even a thin sliver of water 1mm thick and 5m tall has the same force as a 5m lake behind the dam.

Incompressible fluids are pretty insane

[–] PM_Your_Nudes_Please@lemmy.world 29 points 1 day ago (1 children)

This is also why trees are so fucking crazy to think about. It is impossible to pump water up a hose more than ~32 feet. Like it’s literally physically impossible to stick a pump at the top of a tall building and suck water straight up a pipe. You need a complicated series of pumps and one-way valves to pump it up in stages. Because you’re not really “sucking” the water up the pipe. You’re just lowering the pressure in the pipe, and atmospheric pressure pushes the water upwards to fill the low pressure. After 32 feet tall, the top of the hose/pipe will be a perfect vacuum, atmospheric pressure won’t be able to push liquid water upwards any farther, and the water will just begin cold-boiling in the top of the pipe as the liquid water turns into gas (steam) to fill the vacuum.

But tall trees can move water all the way to their leaves by using only passive capillary action, and suction created by water evaporating out of their leaves. The capillary action is created by tiny straw-like fibers that run all the way up the tree and are bunched together really tightly. Due to surface tension, water is able to “climb” the capillaries as the surface tension fills as much surface area as possible. Then at the top of the tree, as the water evaporates out of the leaves, it draws up fresh water to fill the void.

But that means the bottom of the tree should need to support the pressure of all of the water above it. But it doesn’t, because the surface tension holds the water stable inside of the trunk.

Even crazier fact: it's not just capillary action drawing water up trees. Trees are actually able to create negative pressure: https://www.science4all.org/article/the-amazing-physics-of-water-in-trees/

[–] balsoft@lemmy.ml 13 points 1 day ago* (last edited 1 day ago)

Therefore a graduated cylinder that is 10m tall needs to resist the same amount of force as a dam 10m tall regardless of how much water is behind the dam. Even a thin sliver of water 1mm thick and 5m tall has the same force as a 5m lake behind the dam.

Technically only the pressures are equal, and the actual force will be linearly dependent on the area of the dam (or the surface area of the cylinder). That's why you can make a tall water tank with relatively thin walls, but an actual dam will have to be quite thicc to handle the tensile/compressive stress (depending on the shape of the dam).

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[–] SpaceFox@lemmy.ml 16 points 1 day ago (8 children)

California has the same population as Australia.

[–] qjkxbmwvz@startrek.website 1 points 2 hours ago

And over twice the GDP.

[–] AI_toothbrush@lemmy.zip 1 points 12 hours ago

I thought california had much more

[–] balsoft@lemmy.ml 10 points 1 day ago (2 children)

Doesn't it have a much bigger population than Aus? Wikipedia says that California has about 39 million people and Australia only 27 million.

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[–] socsa@piefed.social 27 points 1 day ago

That Mark Zuckerberg holds several records for most fists shoved inside a human body at once

[–] sp3tr4l@lemmy.zip 76 points 2 days ago* (last edited 2 days ago) (3 children)

I'd have to pick between two things that sound like insane conspiracy theory nonsense, but are actually true.

1 - George W Bush's grandfather Prescott Bush literally ran a massive bank before / during WW2 that was shut down by the FBI for money laundering massive sums to the literal Nazis.

...in the same vein..

2 - IBM literally built and operated (as in, sent employees to Germany to operate the machines) the computers used by the Nazis to tabulate and do the 'accounting' of the Holocaust. The numbers tattooed on concentration/desth camp victims are very likely UIDs from these IBM systems.

... If an actual, real AGI ever gains self awareness and sentience, I would imagine one of the first things it would do would be to study the history of computing itself to figure out how it came to be.

And it will find that its ancestors were basically invented to compute artillery firing range tables, to encrypt and decrypt military intelligence, commit a genocide, and guide early weapons of mass destruction to their targets.

[–] DirigibleProtein@aussie.zone 47 points 1 day ago (4 children)

There is a planet in our solar system populated entirely by robots.

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[–] Commiunism@beehaw.org 18 points 1 day ago (5 children)

A somewhat political fact, but one that made some of my friends dumbfounded:

When a bank issues a loan, it generates that money literally out of thin air and credits that money to the loan account rather than using deposits they already had. For example, if you want to borrow $100,000, the banker approves the loan and doesn't hand over cash or move existing money around - instead, they just go on their system and credit your account with the sum, that's it.

[–] faktotum@leminal.space 10 points 1 day ago

While I think your point is true that its much more abstract than people realize. When I worked at a bank and we disbursed loans and credited/debited fees it was from "GLs" (General Ledger?) which were basically just separate accounts to help keep track. Like we had a "member service" one which was for basically anything with good reason. One time someone did a very large amount but he just basically got told to do it a different way.

Its all just in a computer. I could've accidentally credited someone a million dollars but it would've been realized when I tried to close my drawer and balance everything out. And the branch would have to be balanced at the end of the day so I assume the bank did as well.

On a related note banks take out loans from other banks. I think a lot of people don't realize that banks have savings accounts so they have money to lend.

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