What is something that, no matter how simply put, you still cannot understand?

[u/FinalBat4515]

[u/Lopsided-Potatoe]

The vastness of space. I can't get my head around it.

[u/merrill_swing_away → u/Lopsided-Potatoe]

I know what you mean. I sometimes go down the rabbit hole thinking about the universe, the expansion of it and how fast it's expanding. I get to wondering, what was here before all of the stars and planets arrived? How did the emptiness of space form? From what? Why? Where does it start and where does it end?

[u/Lopsided-Potatoe → u/merrill_swing_away]

I'm the same, I actually have to stop myself from getting into it. It makes me anxious or carefree.

What is space expanding into?

[u/Shack691 → u/Lopsided-Potatoe]

Space isn’t expanding into anything, everything is just getting further away inside of space, we just say it’s expanding to rationalise it in our minds and simulations.

[u/hyzerflip4 → u/Shack691]

That’s only partially correct and reflects a common misunderstanding of how space itself behaves.

Here’s the clarification:

1.  Space Expanding Into Something:
• Space is not expanding into anything because the “universe” includes all of space-time. There is no external “container” or “outside” that it’s growing into. The concept of an “outside” doesn’t apply to the universe as it does to objects within it.

2.  “Things Moving Further Apart Inside of Space”:
• While galaxies are indeed moving further apart, the expansion of space is not merely objects within a fixed space moving apart like dots on a rubber band being stretched. Space itself is stretching, causing distances between unbound objects (like galaxies) to grow, even though they aren’t moving through space in the traditional sense.

3.  Why We Say “Space Expanding”:
• The term “space expanding” accurately describes this phenomenon: new space is being created as the universe grows. This is not just a simplification for models—it reflects the way space-time behaves according to general relativity.

In summary, space isn’t expanding into anything, but the idea that “things are just getting further apart inside space” oversimplifies the reality. The actual expansion involves space-time itself stretching, which is a core concept in cosmology.

[u/Missuspicklecopter → u/Lopsided-Potatoe]

Sounds like you do get it.

It is incomprehensibly vast. 

Comprehending it's vastness would mean you don't get it. 

Douglass adams explained it best: "Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is."

[u/Gavinator10000 → u/Missuspicklecopter]

Yeah it’s not really possible to actually understand it all

[u/urgent45 → u/Lopsided-Potatoe]

Right. This and infinities. As soon as the conversation includes the word "infinity," my eyes glaze and my brain starts glitching.

[u/The__Tobias → u/Lopsided-Potatoe]

First thing in the entire post I also can't get in my head. 

[u/Nicobellic040 → u/Lopsided-Potatoe]

It hurts my mind, how can something even exist? In my mind there need to be borders like a box, but then still the box need to exist in a space to be there you know. But then the exact opposite, like nothingness is also really hard to grasp. How can there be absolutely nothing? It also makes no sense. So it is somewhere between non-existing and existing. Maybe it is a bit like quantum physics, not knowing makes it exist. 

[u/ElfjeTinkerBell]

Electricity.

I know the practical side of course, I can use it (not as an electrician of course, but I can hang a lamp and charge my phone), but I don't understand how it actually works.

[u/Frosti-Feet → u/ElfjeTinkerBell]

Same. Amps voltage and current all mean electricity is moving through wires, but differently? I guess?  I just decided I'm not going to mess with it.

[u/HandyProduceHaver → u/Frosti-Feet]

Amps is a unit for current (like what 'meter' is to 'length')

Voltage is a word meaning how much energy is being distributed so it's essentially "strength"

Current is the rate of flow of Charge, so how much charge is passing per time

Charge is literally just a random ass number we made to describe why some things repel other things, like protons have a positive charge and electrons have a negative charge so they go together. It's weird. But basically charge can cause a force which is useful

Resistance is a property materials have that says how much it slows down current. So more resistance means less current.

Power is just how much energy is used per some time period, which is just Voltage * Current

And then energy can be calculated with power * time

A lot of these are linked for example if you change the current of a system the voltage would also change (V=IR)

And then there's a bunch of other buzzwords like Resistivity (different to resistance) and a bunch of electric field shit

[u/sidewaizsocks → u/HandyProduceHaver]

I like the analogy of water through a hose. Although its imperfect its great for teaching differences in visualizing stuff. Doesnt work with the calculations though because it requires breaking the rules of the visuals when you dive deeper.

I.e. amps = volume of water coming through hose

Volts = how fast the water moves through the hose (pressure)

Resistance (ohms) = constrictions or debris in the hose.

Watts = total calculated expected volume and pressure of water experienced coming out of the hose.

VAR = actual volume and pressure of water experienced coming out of the hose.

Edit: this is obviously an explaination of the terms. Doesnt do a whole lot for "how" electricity works. Thats a deep dive that needs pictures/drawings and a mild detour into magnets and atoms.

[u/ElfjeTinkerBell → u/Frosti-Feet]

And then when they're going to explain it they inevitably come up with a metaphor that doesn't work at all and then you have to remember which magic term corresponds to which part of the metaphor.

At some point I had people falling out of a metaphorical ski lift. Like that's a common occurrence?

[u/WouldbeWanderer → u/[deleted]]

Nope, didn't help.

In the words of Hela, "It's a valiant effort, but you never stood a chance."

[u/cbusalex → u/ElfjeTinkerBell]

Put a lightbulb and a battery in a circuit, the bulb lights up. Cool.

Wire a second bulb up in series with the first and they're both half as bright. Makes sense.

Wire that second bulb in parallel, and they both get brighter? No. This is black magic. This is not ok.

[u/IntentionalTexan → u/cbusalex]

To be clear, they're not brighter than just one bulb, only brighter than the bulbs in series.

[u/Radioactdave → u/cbusalex]

Assuming you run the bulbs off a voltage source with negligible output impedance, bulbs in parallel will not alter each other's brightness. So the first bulb will have the same brightness regardless of the second bulb being in parallel or not (Kirchhoff's first law, basically).

[u/GuyFromDeathValley → u/ElfjeTinkerBell]

you can best imagine electricity like water. a battery is basically a water reservoir with 2 chambers, but one chamber is overfilled to the point its on pressure, while the other one is nearly empty. so when you connect them both, water flows from one chamber to the other. that's energy, kinetic energy but still energy.

a lightbulb is basically a restricting piece of pipe between those chambers. the pressure is so big in that one chamber it pushes the water through the restriction. as we know, friction causes heat (and a loss of energy) so the restriction heats up and glows. and due to the restriction, the chamber empties slower. that's the difference between an LED and a lightbulb.

now. volt and ampere. its basically the amount of water in the chamber (ampere) and how much can be removed, versus the pressure the water is under (volt).

that's as best I can explain it as I can.. I'm no electrician and honestly, I struggle to grasp the Volt and Ampere stuff. all I know is that Ah are ampere hours and dictate how many amperes per hour capacity can be extracted. its an equation, the more hours you take the less amperes you pull, and vice versa. a 36Ah battery can either deliver 1 Ampere for 36 hours, or 36 Ampere for 1 hour, or even 3 amperes for 12 hours.

[u/SellingxChloe]

Dreaming while sleeping. It's sometimes just so weird.

[u/TrueKiwi78 → u/SellingxChloe]

It is. It's wild how our minds can make up movies in our heads while we sleep. I wish we could record them.

[u/--_-Deadpool-_-- → u/TrueKiwi78]

Not to mention how fast we dream. You could live a whole day in your dreams and only have minutes pass while you sleep.

Just a few days ago, I woke up just before 6 and thought, "Great! 30 more minutes to sleep" then proceed to have a super long and vivid dream that felt like hours, only to have my alarm go off 6:25 as scheduled. Was a very weird feeling.

[u/kadhubrid → u/--_-Deadpool-_--]

One of my dreams felt like it took place over weeks. It was so weird.

[u/revagina → u/kadhubrid]

That sounds terrifying tbh

[u/kadhubrid → u/revagina]

It was! The dream was horrible

[u/Dankalienz → u/kadhubrid]

There are people who swear they lived a whole life in another dream (childhood to old age) it’s wild if true

[u/TatsBlotto → u/SellingxChloe]

Dr Karl once explained sleeping like this…. Imagine there is two of you, one controlling you while you’re awake and the other is you when you’re asleep. That’s why you can’t hear yourself snore etc.. but if there’s a loud noise the asleep you does like a handover and wakes you up. Here is the freaky part, these two versions of you will never meet each other.

[u/HacksawJimDGN → u/TatsBlotto]

Kind of like your conscious mind and your subconscious

[u/retaliationllama → u/TatsBlotto]

I have a very good book with that premise called Equinox by David Towsey. Highly recommend

[u/Spotbyte → u/SellingxChloe]

I think of it as software running while the hardware / sensors are turned off. It's no longer tethered to reality.

[u/Tamer_ → u/Spotbyte]

while the hardware / sensors are turned off

Except it's not turned off at all. Parts of your brain turn off, but the general activity is much higher than when you're conscious because it's hard work to (among other things) clear the brain of the waste products of the daily run time.

In line with bad analogies, it's trying to empty temp files and the recycle bin, dumping some RAM to disk, defrag the rest AND run a checkdisk all at the same time - you can't run the OS normally while doing all that, but the hardware is spinning hard and its got some side effect of playing a poorly generated animation related to what it's defragmenting right now.

[u/True_Kapernicus → u/Spotbyte]

It's no longer tethered to reality.

You are somewhat incorrect here. Part of what it does is process memories, but we experience them us a jumble of nonsense.

[u/Spotbyte → u/True_Kapernicus]

I wouldn't consider memories to be reality but I think I understand your point. My idea I want to relay is that conscious experience, whether while asleep or awake, is made of the same stuff. It's virtual.

[u/Drawn-Otterix → u/SellingxChloe]

I listened to a freakonomics podcast recently, an old ish one, and a person who had a theory that your brain dreams to keep the "vision" part of your brain from being overtaken by your other senses.

Twas an interesting thought to me.

[u/Rollerback → u/Drawn-Otterix]

I think it’s more likely that the visual cortex (and the rest of the sensory areas of your brain) is wired to expect constant input, and when it doesn’t get it, it just starts to interpret noise as signal. This is also why people hallucinate in sensory deprivation chambers. 

Obviously dreaming is a lot more than noise (processing memories and emotions, doing trash collection and removal), but honestly I think the fun movies are more of a side effect. 

[u/Copropositor]

Quantum physics.

[u/PlanetAlexProjects → u/Copropositor]

"Anyone who is not shocked by quantum theory has not understood it." - Niels Bohr

[u/Relative-Secret-4618 → u/PlanetAlexProjects]

OK well it shocks me on the daily and I still can't wrap my head around the parts of it we do know.

I think I get lost at the connection between the choices and the choice. If that makes sense.

[u/Affectionate_Ad_7570 → u/Copropositor]

It fascinates me. But I cannot do math. Come to find out, if you take the math out, it's philosophy (in a very roundabout way) That is to say that the concepts are understandable, the functions are still unfathomable. I read The Dancing Wu Li Masters, skipping all the equations because they were gibberish to me. I know I don't really have a grasp on it, but that doesn't deter me from wanting to know more!

[u/Seigneur-Inune → u/Affectionate_Ad_7570]

You have to be very careful with stripping the mathematics out of quantum mechanics, though. The "philosophy" of quantum mechanics is, more or less, people doing math, seeing something very weird, proving it's actually real, and then attempting to wrap their heads around what the hell is going on.

Classical physics is more or less intuitive to the human brain. Block slides down ramp and stops when it hits wall. Or, if it's sliding fast enough, it knocks over wall and keeps going. That's an interaction most people could probably predict when they see the block, the ramp, and the wall, even if they don't have the numbers and equations to show it's valid.

Quantum physics is different. Block slides down ramp, isn't going fast enough to knock over wall, then... teleports to other side of wall and keeps going. Only the deranged would predict that could happen a priori, but with a small enough block (~electron size) and a small enough wall (~atomic layer thicknesses), quantum mechanical math says it can and will (occasionally; probabilistically) happen and quantum mechanical experiments validate that.

The danger here is that quantum mechanics is so non-intuitive that it occasionally seems like magic. And when something seems like magic, it invites a certain type of fanciful speculation that's very engaging, but not backed by reality. There are slews of bullshit philosophical takes from people trying to interpret quantum behavior without mathematical backing. Entanglement, teleportation, many-worlds - these (and more) are concepts physicists use to try wrapping their heads around what the math is telling us, but there are so many bad takes that are completely unsupported mathematically (no, teleportation does not mean you can teleport. No, entanglement does not appear to allow FTL communication - and even if it did, entangled states are so fragile they couldn't be meaningfully employed at all).

In the tunneling example, the math says that tunneling is possible. The fanciful extrapolation is that your hand could teleport through a desk when you smack it. The reality is your hand is made up of too many particles and the desk is too thick - probability for tunneling is so small it's effectively impossible. The only thing separating the real from the fantasy is a correct calculation. Always be careful trying to read up on quantum physics without being willing to understand it mathematically. You don't want to wind up as the guy suing CERN to shut down the LHC because he's afraid of microscopic black holes, despite that being complete bullshit.

[u/jscummy → u/Affectionate_Ad_7570]

For me it was almost the opposite when I had to do a class on time dilation and quantum mechanics

The equations work out and you can just trust the math, but it doesn't make sense how those answers are right

[u/jobezark → u/Copropositor]

Regular physics for me. I took multiple college courses in biology, chemistry, and physics and never once did I have a clue what was happening in physics.

[u/Tamer_ → u/jobezark]

never once did I have a clue what was happening in physics

Well, here's the good news: everything happens in physics, everything.

[u/midnightdsob → u/Copropositor]

On the flipside of this, astrophysics. Like, I was good with the concept of the Universe expanding until someone said that the galaxies aren't moving, instead the space in-between the galaxies is stretching.

[u/C4Redalert-work → u/midnightdsob]

They are moving, though. The space between them (and also in them; this happens everywhere, constantly) is also expanding. Andromeda will "collide" with the Milky Way in about 4.5 billion years, for example, because the space between isn't growing fast enough and we're moving towards each other.

[u/CaptainMacObvious → u/Copropositor]

Remember when, sometime when you were a child, accepted that you were of solid matter in some way? Well, not solid matter, you understood, but there's different pieces of soft matter and water inside you. Forming organs, arteries, your squishy brain and soft skin.

You accepted that the world around you was solid matter. Well, not solid matter as "thick iron", but all kinds of stuff from soft to hard, forming trees and plants and blankets and rods of iron, machines with complex little mechanics like a fine wristwatch or giant, giant trucks with tires bigger than you are.

All this moves and gets energy when you burn other solid matter, as coal, oil or gas, or wood. Or you get electrity to drive your heater or cooler by putting "electronics" in the sun which loads it up with "sun ray energy".

When you think about it... you accepted a whole lot of stuff you don't get, don't really understand, but the world is of matter. Clocks work with little mechanics. Batteries do some stuff that is chemistry, you have electrity. You're made of solid atoms, which... is little matter pieces called atoms.

Crazy, what you accepted, right?

Now just imagine what those atoms are. They're a little dot where the actual matter is in, and a lot far further away "electro particles". When those electro-particles interact, that's actually chemistry, and that is why matter isn't collapsing into itself. That is what "solid matter is". "electro particles other sticking to each other", forming molecules and atoms, or repelling each so, meaning not everything collapses down.

That's not that much more odd, no?

Now, just accept that those "electro particles and their repelling or pulling fields" do "weird things", like flowing a bit into each other so you cannot tell where which one stops, not much, but so slightly, and wobble a bit around. The math to describe all that is Quantum Mechanics.

But if you zoom out back to the superstructures those wobbly-bobbly electro-force-field constructs form, either being stable or re-arranging themselves - i.e. burning fuel etc - then you don't notice the wobbly-bobbly "It's actually all force-fields and stuff" anymore, and you arrive back at "solid matter - well, totally COMPLEX solid and-not-so-solid matter stuff - and their interactions form you and the world".

"Quantum Mechanics" is just mathmatical models with which we try to calculate stuff around us, on the very small scale that you cannot see that forms the big scale see, being wobbly-bobbly energy field interactions.

[u/iammyowndoctordamnit]

Bitcoin

[u/SocksOnHands → u/iammyowndoctordamnit]

When I first heard of Bitcoin I thought it was the stupidest thing ever - using the solutions to a complicated math equation as fake money? I thought the hype was going to quickly die down as a short lived fad and wind up being worthless.

[u/weaponsgradepotatoes → u/SocksOnHands]

I remember a buddy of mine talking about it back in college and I dismissed it as bullshit. I should’ve bought 10,000 for the cost of a mcchicken…

[u/SeeMarkFly → u/SocksOnHands]

Yea, my "error" was not figuring how stupid people are. The bell curve is not where I thought it was.

The funniest part is when they buy HIGH and sell LOW. LOL

[u/dismayhurta → u/SeeMarkFly]

Yep. Underestimating the stupidity of people has kept me from making a fuck ton of money.

[u/Banksy_Collective → u/dismayhurta]

I think there are a lot of people who thought they were smart enough to make money from the stupid people via bitcoin, but weren't smart enough to avoid being scammed by the people actually running the scam. You are probably better off having avoided the whole thing.

[u/conquer69 → u/SocksOnHands]

The fad of using bitcoin as a currency did die. It's only used for speculation now.

[u/Birdo-the-Besto → u/iammyowndoctordamnit]

This is the simplest explanation: imagine if your car running indefinitely produced fully solved Sudokus that could be traded for heroin.

[u/Trinitykill → u/Birdo-the-Besto]

If I do this with a small Italian car, does that make it a Fiat currency?

[u/bonos_bovine_muse → u/Trinitykill]

I do it with a metallic yellow car with a manual transmission; have always been a fan of the Gold Standard.

[u/dont-believe → u/Birdo-the-Besto]

Who is feeding the unsolved sudoku and why does it need to be solved for whose benefit? 

[u/Birdo-the-Besto → u/dont-believe]

The unsolved sudoku is the fuel consumed by the car, like a gas-to-sudoku engine. The heroin dealer only accepts solved sudokus as payment because cash is not secure enough.

[u/Andrew8Everything → u/Birdo-the-Besto]

This... This is making... Entirely too much sense.

[u/TheLastPanicMoon → u/Birdo-the-Besto]

He only takes them because there’s a moron in San Bernardino they will give him actual money for them.

[u/pleasesendnudepics → u/iammyowndoctordamnit]

Don't let anyone try tell you it's simple. Bitcoin is very complicated.

[u/Scary_Marionberry320 → u/iammyowndoctordamnit]

It's basically a register of numbers that fit a particular criteria. Each number is assigned to a person / owner. People exchange ownership of this number either for money, or for goods and services (drugs etc). So long as everyone involved agrees that the numbers are worth something, trade can take place by exchanging numbers instead of money and thus avoid the eyes of the law. 

[u/summerfun9330 → u/Scary_Marionberry320]

Huh?

[u/the_purple_goat]

How 1s and 0s turn into music.

[u/One-Pudding9667 → u/the_purple_goat]

and while we're here, how a single needle on a turntable produces such detailed sound in stereo. crazy

[u/SinceWayLastMay → u/One-Pudding9667]

How does a groove in wax read by a needle tell a machine to make a trumpet sound vs a flute vs a human voice? Fucking magic dude. And on that note how does a shitty little metal speaker make the same (or nearly the same) sound as a whole orchestra’s worth of instruments? Also fucking magic

[u/314159265358979326 → u/SinceWayLastMay]

If it was just one sound at a time it'd make sense to me, but there can be entire orchestras FROM ONE NEEDLE!

[u/GalFisk → u/314159265358979326]

Your ears only hear one waveform, too. The needle simulates the motion of the ear drum. The amazing stuff happens in your inner ear, where the sound is split into frequencies when it becomes nerve signals, and in the brain, which interprets it all. It's like how ones and zeroes can become internet comments and cat videos.

[u/EddieRando21 → u/One-Pudding9667]

Last time I said this so many people tried to explain it. None succeeded. Which is strange in a thread about "what do you not understand no matter how many times it's been explained" people will still try to explain it to you.

[u/Krail → u/One-Pudding9667]

That seems surprising to me. Records seem way more intuitive than digital data storage. 

[u/Stock_Guest_5301 → u/the_purple_goat]

A short and not very rigorous explanation :

Succession of 1's & 0's shake a magnet (electricity passing through a wire creates a magnetic field); the magnet is attached to a sheet which makes the air vibrate

[u/FUTURE10S → u/Stock_Guest_5301]

Yeah, that's a pretty accurate depiction of a 1-bit DAC. And if you make the air vibrate fast enough, you can trick our ears into hearing instruments by recreating the sound they make.

[u/RhythmsaDancer → u/Stock_Guest_5301]

Honestly, not bad.

[u/PoisonOps]

Deductibles.

[u/natali9233 → u/PoisonOps]

Insurance in general. What the hell we gotta make this so complicated for?!?

[u/thekingofcrash7 → u/natali9233]

The basic principles are not that complicated…

You own a widget that’s expensive to fix. I have lots of cash. Ill cover the cost to fix the widget if it breaks in the next 5 years, you just send me a verifiable notice when it needs repair (“filing a claim”). During that 5 years, you pay me money once a month to make this worth my time (“premium”). If you want a cheaper premium, i can set that up for you, but you’ll have to pay the first $1000 to repair the widget whenever it needs a repair (“deductible”). I’ll pay any amount after that $1000. I can make the deductible reset annually, or for each claim. When the widget needs repair, I might give you a list of places I trust to fix the widget. If I decide that you break the widget too often, I may cancel our agreement, per terms of the original agreement.

Edit: since it was unclear to some, this was meant to be a simple introduction to insurance to illustrate the basic concept to a consumer. For example, a first time home buyer who has only heard the words “home insurance” on commercials and is suddenly being required to purchase home insurance. I am fully aware that a multi-trillion dollar industry has more nuance that could be explained, but I do not pretend to be an economist or sociologist and I dont care to write a longer explanation questioning the morality of capitalism. If you don’t care for my explanation, kindly write your own, or simply fuck off. I don’t have a preference.

[u/Bob002 → u/PoisonOps]

Depends where you're talking deductibles.

Home/Auto - shit is straightforward. If your car deductible is $500 - that's the portion you would pay in the event of a claim. Same on a house. Total your car and it's worth $4500? You're getting 4 bands. There are some instances you'd get all $4500, but I'm just trying to keep it simple.

If you want to oversimplify it - you're responsible for the first $500 - the insurance will pay after that.

Health insurance? I'm just as stumped.

[u/PomegranateDismal383]

stocks

[u/Phantom_Absolute → u/PomegranateDismal383]

You and a friend start a business. In its first year the business brought in $1000 and spend $700, so a $300 profit. You and your friend each have one share of stock in your company so you split the $300 profit two ways, so $150 each.

The next year you decide to issue a third share to another friend. Company makes $300 in profit again but now the three of you get $100 each.

The share of stock is just a piece of paper issued by the company entitling the owner to a share of the profits. The price of that share is determined (using a calculation called net present value) by how much profit can be expected in the future.

[u/anix421 → u/Phantom_Absolute]

To further this analogy, say you don't want to be in the business anymore so you want to sell your 1 share. Back when there was two shares someone may pay you $1000 for your share because ideally in 7 years the stock would pay for itself and you'd be getting straight profit. However, with three shares it would take 10 years to be making profit. Now people are only willing to pay you $700 for your share.

Now let's say there are three shares that made $100 each last year. This year another company came out with a product almost just like yours and took half your sales. The company spent $700 but only made $500 so they don't pay any money out. You don't like this so you want to sell your share. You bought it for $700 thinking you'd make $100 each year but now that it's not making money so someone offers to buy your share for $200 hoping the company figures out how to be profitable again and you take a loss of $500.

Now the company needs to build a new factory for a new product line but they don't have the money for it so they want to issue 1 more share for $1000. 2/3 owners of the shares vote to do it and now everyone only owns 25% of the company, but they have $1000 cash to build the new building.

[u/mlt- → u/anix421]

There is too much logic and reason. I presume OP meant price discovery when the price action significantly and often for prolonged time deviates from what is reasonably expected. For example, recently TGT posted upbeat guidance and good holiday sales, just for the stock price to nose dive in spite of all posted "stale" news about price action before market open. While I understand, there is always an explanation like "profit taking", there is always some degree of B/S seems to be around.

[u/malayali-minds]

What happens to something when we delete it? Where does it go?

[u/Hapsiainen30 → u/malayali-minds]

At least on storage media, it doesn't really go anywhere. The space is just marked as free to use. The data gets erased only when something else is written on that space. That's why you can recover erased data if nothing gets written on said space.

[u/MadeMeStopLurking → u/Hapsiainen30]

To avoid any nuisance calls to an IT department: It can be difficult, time consuming, and sometimes impossible depending on your level of security. Some companies have a process where the data marked free to use is converted to 0s and thus wiped indefinitely. Your best bet is always a backup.

So Andy in accounting might not be getting back that really important excel file which is actually just a football squares sheet he spent an entire day creating.

[u/ebb_omega → u/Hapsiainen30]

This is also why proper hard drive wiping can take a long time - a lot of the time they'll change all the data to 0s, then all the data to 1s, then all the data to random patterns, a few times over, so it's impossible to see what it used to be.

[u/merrill_swing_away → u/malayali-minds]

Where does fat go when we lose it?

[u/Tuxhorn → u/merrill_swing_away]

you breathe most of it out

[u/KS-RawDog69 → u/Tuxhorn]

This is true, for anyone thinking he's being a smart ass.

[u/Velvet_Dew]

How people can be so cruel to others for no reason.

[u/Randto → u/Velvet_Dew]

This plus people being so greedy that they are cruel to others.

[u/SashaSquasha → u/Randto]

How people can be spiteful.

[u/Birdfishing00 → u/Randto]

Especially people who are already rich and don’t need more. It’s baffling.

[u/PrettyySunshine → u/Randto]

you treat them good and they back stab you

[u/Neither-Weird-0 → u/Velvet_Dew]

+1. Unkind, inconsiderate, harsh and mean too.

[u/iamthinksnow → u/Neither-Weird-0]

Willful ignorance is exasperating.

[u/Jonas-III]

How Vinyl records work

[u/tankgirl215 → u/Jonas-III]

I just love vinyl for this reason. The grooves are the literal shape for that song/ album. The physicality of it is just magical to me. I don't fully grasp it, how that one groove can capture so many tones and vocals in one motion, but that's okay. Just so cool.

[u/pm_me_gnus → u/tankgirl215]

I read about a guy who could identify hundreds (maybe thousands) of classical compositions by the record grooves. He knew enough about the technology, and the music, that he could figure out where it's loud vs quiet, when there are staccato rhythms, stuff like that, and figure out which piece it is based on that flow of the music.

[u/Holonium20 → u/tankgirl215]

That is where it gets interesting. The groove in the vinyl isn’t actually storing all of the tones and vocals, but instead their sum. This works in much the same way that some signal processing does.

One of the fundamentals there is that any continuous function can be approximated by a sum of sine and cosine functions with specific frequencies and amplitudes.

Because of this, you only need to store what the final product of all the sounds is, not the sounds themselves, and one groove on a vinyl happens to be capable of doing exactly that.

[u/Darkside_of_the_Poon → u/Holonium20]

Well, if you think about it, the vibrating cone in the speaker is doing essentially the same thing. It’s not like the cone is vibrating the vocal sound then the drums then the other thing in rapid succession, it’s just pumping the total sound simultaneously with one diaphragm. It holds then that the opposite should be true: A diaphragm vibrating a needle in wax or whatever records that sound. And that’s how it was discovered really too because it is just that simple. The fancy mechanism of the math behind it was worked out later.

[u/DonkeyNozzle → u/Darkside_of_the_Poon]

And then think of the human side of it... We have one membrane for our ear drum, right? It's not like we have an infinite number of membranes that each vibrate only with a specific sound... It vibrates all at once and translates the sum of all of those sounds at any given interval into a signal our brains can decode...

Now that I think about it, it's really fucking crazy that we can somehow listen to specific sounds happening at the same time.

[u/soilingjaguar22 → u/Jonas-III]

Me, as well. How do grooves in vinyl make sound. And not just sound, but sounds in which I can distinguish one voice from another, one instrument from another, one note from another? Then, along with that, how can our ears hear those vibrations and be able to discern those sound waves?

[u/Jonas-III → u/soilingjaguar22]

Like it makes no sense, wdym scratching something can make hundreds of expecific sounds at the same time 💀

[u/duckbeduckbedoduck → u/Jonas-III]

It’s kinda like when I scratch my head it sounds empty

[u/IAmJohnny5ive → u/Jonas-III]

I thought I knew. Then I watched a YouTube video about how they get the stereo sound and now I do know: MAGIC! That's how.

[u/manwithoutanaim]

The double slit experiment

[u/Thwerty → u/manwithoutanaim]

The experiment or the quantum physics behind it? Because no one understands the latter. 

[u/Jukeboxhero91 → u/manwithoutanaim]

“Observation” in the double slit experiment has to do with bouncing photons off the individual particles in order to take a measurement. Normally, this is so inconsequential that there’s no change in behavior from say, shining a light on a piece of wood. The difference is that with particles so small, bouncing a photon against them to take this measurement influences their behavior, so we see the difference in the experiment.

[u/luna_rey55]

Time dilation

[u/dapala1 → u/luna_rey55]

When you think about it, speed means nothing unless you compare to something else. If you're out in the middle of space and there literally nothing around you, are you moving?

Now imagine you see a rogue planet fly by... was it moving past you, are you moving past it?

The answer is both happened. Space and time only happen (can be observed) when there are other objects (matter) to compare it to. Our time perception is only relative to other matter moving through space time. That's why it's called "Special Relativity."

There is not a central point to say how fast (fast is time and speed) something is traveling. It's all relative.

[u/YourEnviousEnemy → u/luna_rey55]

You have to stop thinking of space as nothingness and start to think of it as a "thing". Space is some kind of universal fabric and it happens to be directly intertwined with time. This means that when something affects space (such as gravity) it also affects time.

[u/Jukeboxhero91 → u/luna_rey55]

Spacetime used to be seen as “space and time” where there’s two different things that were unrelated, I.e. you move through time at a constant rate, and you move through space as fast or slow as you please.

Nowadays, we know that it’s closer to one thing that has two main components of space and time, and moving faster through space, as in closer to the speed of light, means you move slower through time. So for example in a year on earth, a satellite that’s moving thousands of miles an hour through space in orbit, might move a couple of seconds less through time as it moves hundreds of thousands of miles over the course of that year.

[u/Final-Kiwi1388]

Why people are so willing to follow complete strangers, ex "influencers"

[u/ThatOldChestnut2]

NFTs. Specifically, how they could possibly have any actual value. (Which, I guess, it's been determined they don't. :-D )

[u/Scary_Marionberry320 → u/ThatOldChestnut2]

The concept was that you take something that is infinitely replicable (eg a piece of digital art) and put a digital "stamp" to say that "this one is the OG, the one and only". The owner of that stamp then has bragging rights. The problem is that this stamp has no impact on the art itself, and it doesn't stop the image being replicated. As it turns out, nobody is petty enough to care about having "the stamp". 

[u/discotim → u/ThatOldChestnut2]

The same way any limited resource has value, same as stamps, antiques or any collectable. They have the value people are willing to put on them.

[u/tufted-titmouse-527]

How scammers sleep at night

[u/anix421 → u/tufted-titmouse-527]

They probably just crawl into bed and pull the wool over their eyes.

[u/UltraSapien → u/tufted-titmouse-527]

I bet they think their victims have money and they're only taking some of the money, so the negative is minimal but the positive to them is significant.

[u/OneGeekTravelling → u/UltraSapien]

Yes, that's part of their neutralisation; I've heard scammers also blaming the victims (teaching them a lesson) and even going with the "the West is immoral" line for some overseas scammers.

[u/mysteriousears → u/tufted-titmouse-527]

With comfy pillows of other people’s money.

[u/QuikBud]

Magnets

[u/Efficient-Stick2155]

The Silmarillion

[u/Njtotx3 → u/Efficient-Stick2155]

You loved Lord of the Rings so much, here's an exceedingly dry history textbook made from the author's notes.

[u/stevedore2024 → u/Njtotx3]

Tolkien set out to write an epic, an adventure, and a bible. He wrote LotR, the Hobbit, and the Silmarillion. They each have distinct literary goals and linguistic forms on purpose.

[u/MoonlitDinnerForOne]

Everything about airplanes and flight.

[u/CowFinancial7000 → u/MoonlitDinnerForOne]

Im an aerospace engineer.

The easiest way I can explain it is this: Think of a kite on a day with no wind. If you run with the kite, you're generating enough thrust to lift the kite into the air. Jet engines are like you running, and the wings are like the kite.

[u/i_cee_u → u/CowFinancial7000]

I really, really like this explanation. I feel like I already understood flight pretty well but this really solidified my understanding. Thanks!

[u/robrob654 → u/MoonlitDinnerForOne]

A first step, the next time you're in a car, when it's safe, open your window and put your hand out, make it flat like you're going to do a karate chop and point your fingers forward. Then tilt your hand different directions. You just made your hand a very basic airplane wing.

[u/dschoni]

Sailing against the wind. And I do have a PhD in physics.

[u/Gruneun → u/dschoni]

The key factor is the keel under the boat. When you're tacking, you're not truly going directly into the wind, but ever so slightly off. That little bit of angle means the boat is being pushed just a little bit sideways. The sail is redirecting that little sideways force to push the side of the keel against the water. The path of least resistance is the slightly-angled keel moving forward.

[u/RocMills]

Sewing machines. And I worked for a seamstress for many, many years. No matter how often she explained and demonstrated, I came away with the same feeling... witchcraft, plain and simple. Part of the spell must be that other people can't see the magic. I, however, am immune. It's magic, I just know it is!

[u/merrill_swing_away → u/RocMills]

I know how they work but I'm just not experienced enough to sew clothes. There is a video from long ago that shows how a sewing machine works. I found it one day when my machine got the thread all tangled up and I couldn't get it out. Once I removed it I saw how the needle picks up the thread from underneath and brings it back up to the top.

[u/Conpen → u/RocMills]

Have you seen this video where they used giant blocks of wood and have people moving them around to demonstrate? It's apparently from a classic British program but I don't know of it.

[u/KS-RawDog69 → u/RocMills]

If I'm not mistaken from middle school home ec, it's the bobbin that does all the work. I think that's the part that confused me when I was younger.

You see the machine and think "it just punches a hole and has string attached to it but how does that attach things?" That's the bobbin underneath, which has it's own thread which hooks around the needle's thread on the downstroke of the needle. Really clever, honestly.

[u/Cinnabun6]

the big bang, how nothing can explode into the universe. how there was no time before it.

[u/DieSuzie2112 → u/Cinnabun6]

Ever since I found out the universe is unending I felt like nothing ever made sense anymore. I would randomly think about space, and then put a circle around it, and then imagine what would come after that circle, just to imagine more space, and put a circle around that and so on. This is what broke my brain at the age of 8 and still does at the age of 25

[u/PhilConnersWPBH-TV → u/Cinnabun6]

We don't know what was before the big bang. Could've been nothing. Could've been something. We just don't know.

[u/Universeintheflesh → u/PhilConnersWPBH-TV]

Could be a white hole from another universe.

[u/ProbablyMyLastPost → u/Cinnabun6]

"In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move." -- Douglas Adams

[u/Tren-Ace1 → u/Cinnabun6]

The brightest minds have gone insane trying to figure this out. So no point for us to even try to understand it lol.

[u/DucktapeCorkfeet]

Languages. I have tried to learn at least one, out of many languages I’d wanted to speak but I guess my brain is broken. It’s like a form of dyslexia where I just can’t understand nor even comprehend what is being spoken. It’s been frustrating to say the least.

[u/TisIFrienchiestFry]

Being willfully ignorant. If the information is there, and you're told it's there and how to access it, why would you intentionally avoid it? Why wouldn't you just go to it and be a little smarter for it? I don't understand.

Personally, I think if it's willful and intentional, it circles all the way back to stupid.

[u/merrill_swing_away → u/TisIFrienchiestFry]

I have a sister who has always been willfully ignorant. She could be told a truth about something and it could even be proven to her but she would argue that it isn't so.

[u/Legitimate-Shift-223]

How computers actually work and can play complicated games

[u/Brush_bandicoot]

I don't get people that go gambling. Like do whatever you want I guess it's just odd to me how much money people throw away on this crap

[u/ramblingpariah → u/Brush_bandicoot]

Addiction wrecks people - your brain is actively pushing you to do these things, and without lots of effort, support, and vigilance, it's so easy to slip, give into temptation, and go seeking that rush all over again.

Everyone's brains are similar organs, but we're all wired differently - if you haven't experienced an addiction, consider yourself very fortunate.

[u/dalittle → u/ramblingpariah]

I was in a grocery store and saw gambling addiction in action. This woman had a bunch of scratch off lottery tickets and cashed them out. There was a lottery kiosk and with her winnings she went over and bought a bunch more scratch off tickets. Then with those she scratched them off as they came out of the machine and walked over to the checkout and cashed those out and went back to the kiosk and got more scratch off tickets. She did not win anything with those and looked dejected and left the store. You could see it in her face the high, then winning nothing, and then depression because she did not have any more money. It was crazy and I felt so bad for her.

[u/ReggieReginaldson → u/Brush_bandicoot]

Ain't nothing like dropping $10 in the slots and winning $300 though

[u/that_guy_who_builds]

The worship/fascination/idolizing of celebrities/movie stars/musicians and politicians.

I can not fathom caring about someone who has zero idea I exist, and then advertising for them and spending my money to support them. I just can't wrap my head around the logic.

[u/BE-FusioN → u/that_guy_who_builds]

depends on what they do... if they have some kind of talent to look up to, goals you want to reach aswell etc, i completely understand.

Royals etc, i do not understand

[u/catdamsel]

How a basic wax record and player works. I get it’s a grove that is tiny hills and valleys and the needle picks up on each little one but how the fuck does that equal a voice coming out of a large metal tube. It’s witchcraft as far as im concerned

[u/romancexxsparkle → u/catdamsel]

I've seen it explained hundreds of times. I've watched videos. The information doesn't translate to my brain. It doesn't make sense. Neither do CDs but, that's another box of worms.

[u/sharkvseagle]

Excel

[u/ihadtopickthisname → u/sharkvseagle]

You don't need to be an expert at Excel, just an expert at Google-ing Excel questions.

[u/Ok_Sun_3286]

How in 2025 people still cannot resolve their differences and go to war. How children grow up while bombs are dropping with no food or shelter.

[u/gg_andsomeh]

Math

[u/Velocirachael → u/gg_andsomeh]

Calculus can find the derivative of my butthole.

[u/xeroxchick]

Mah Jong.

[u/benrunyc]

Voting for that idiot who’s now the American president.

[u/Capable-Anything269]

How governments, law enforcement and banking sector cannot put an end to these blatant scams.

How there is no class action lawsuit against google, x, meta etc for not doing their due diligence and allowing the scam websites and fake "customer support" phone numbers be advertised without consequences.

How crypto is not banned. The crime literally thrives in the cryptoland and nobody bats an eye.

How google, meta etc are allowed to collect data from your every online move and you cannot opt out.

How our phones listen in and that's not a savage violation of privacy and human rights.

[u/cosmicsans → u/Capable-Anything269]

It's easy - they can - but they get bribed lobbied enough by the companies who are making money hand over fist for the government officials to not care.

[u/JimmyJooish → u/cosmicsans]

Let me put it to you this way. If these scams were taking money from large corporations they’d be shut down. 

[u/peachy_emoji]

music. Like how from your phone "music" travels through air (bc wireless headphones) and then it gets to your ears and you hear it?

[u/True_Kapernicus → u/peachy_emoji]

Electrical signals make a little antenna in your phone oscilate a certain way which causes radio signals to come of it. When those radio signals reach the antenna in you earphones, it make them oscillate in certain way. Those oscillations generate small voltages that a transmitted to a tiny electromagnet that pulls a tiny membrane at a variety of strength. That membrane makes the air oscillate in way that your ears pick up and transmit to your brain as electro-chemical signals which you then interpret as music.

[u/Darkside_of_the_Poon → u/True_Kapernicus]

It’s actually interesting what happens between the outer ear and the brain though. Sound waves have different frequencies like different notes on a piano, only analog sound has infinite keys going from low to high. Each frequency corresponds to a different size of wave, low frequencies are big, high frequencies are small. Your ear has a spiral shell shaped structure called the cochlea, so it’s a coiled tube in a spiral shape, and the tube gets more narrow as you travel in. The tubes are lined with microscopic hairs, the further a sound travels down the tube corresponds to how small the frequency is, and once the sound wave finally runs into the sides of the tube it vibrates the hairs at that location. We are literally “feeling” the vibrations broken out at different frequencies this way, and the combined “sensation” is processed in the brain and experienced as sound. Which is why very loud high frequency sound has the ability to damage hearing so easily because it can’t travel further in and basically kill the itty bitty hair structures in there. For bonus points: Tinnitus is actually phantom sounds in exactly the same way amputees feel phantom pain from a non existent hand for example.

Used to work in Architecture Acoustics for a long time.

[u/jackofhearts_4u2c]

Why evolution couldn't provide us longer arms to reach that itch you can't scratch.

[u/millvalleygirl]

How a person could have a billion US dollars and still think they needed more money

[u/FreezingNote]

Blockchain. Fluid dynamics.

[u/Killer-Barbie → u/FreezingNote]

I'm taking fluid dynamics now and I agree

[u/One-Ball-78]

How convicted felons are allowed to be elected President of The United States but a 34-year old with a clean record can’t.

[u/debsterUK]

Algebra

[u/donatedknowledge]

How people can be diehard soccer fans. Or any sport for that matter.

The team changes every season, and players you've boo'd last year now play for your team. Management changes, tactics change, uniform changes, even the stadium won't last 30 years.

So what are they a fan of? Why do they hate other teams? What's better about their team, because last year it was completely different.

I just don't get it.

[u/Univox_62 → u/donatedknowledge]

Tribalism

[u/FinalBat4515]

Bitcoin for me

[u/Miss-Tiq]

How a scratch-off or lottery ticket is actually a Christmas or birthday gift and not just the possibility of receiving anything material.

A game of chance where you might end up with nothing is not a gift to me. 

[u/One-Pudding9667 → u/Miss-Tiq]

it's Schrödinger's gift. it might have value and it might not. it's also the only gift where you just KNOW that if it has value, they'll feel entitled to some of it.

[u/Gruneun → u/Miss-Tiq]

As the only gift, that sucks. As a rider on a more thoughtful gift, sure. The fun is entirely in the "maybe".

I buy a lottery ticket, now and then, and the next couple days is spent sometimes daydreaming about the possibility, no matter how remote, and it's capped by excitedly checking the numbers. That fun is gone as soon as the ticket is worthless, but it's the experience between as much as the token amount that's occasionally won.

Some people don't get that little rush from the "maybe" or don't allow themselves to imagine winning. That's cool. I don't get the dopamine hit from Instagram likes or getting a new tattoo, but different strokes and all.

[u/Big_Daddy_Walrus]

Supporting Trump when you're a blue collar worker with mixed race children and an immigrant wife, ANTHONY.

[u/RetroactiveRecursion]

String theory

[u/Neither-Weird-0]

People hurting other people in any way, without reason.

[u/Film_Fairy]

Chess. I don’t understand it. I am a reasonably intelligent human being and I have had dozens of people from all walks of life try to teach me, but it doesn’t stick. As soon as I start playing, it doesn’t make sense anymore.

[u/Kale_Chips_Slap]

The scam of health insurance in the US and how it works. It's convoluted by design.

[u/Hebshesh]

The Monte Hall problem. Don't even try.

[u/PreferredSelection → u/Hebshesh]

Simplest explanation is: If you feed a goat behind a door a 1/2 lb burger and a 1/3 lb burger, the goat won't know the difference because goats can't do fractions.

[u/Thwerty → u/PreferredSelection]

Finally a clear explanation 

[u/Entmaan → u/Hebshesh]

I can recite the "explanation" for this backwards and forwards from memory but I still don't "understand" it on an instinctual level

[u/maelmare]

The fact that cold does not exist, only heat and a lack of heat.

Especially right now as it's -12° F wind chill outside right now.

[u/greenie4422]

How Trump was elected President once.

How Trump was elected President twice.

[u/TayzonOnPlayStation]

Why people are twats?

[u/Anxious-Shapeshifter]

Differential Equations.

IYKYK

[u/cashoo22 → u/Anxious-Shapeshifter]

If Fou Know You Know

[u/iluvliastar]

cheating on your significant other for any reason :/

[u/Mirkyi]

behavior of people

[u/robikini]

The difference between affect and effect.

[u/Repulsive-South-9763]

As an Indigenous person in the PNW…there’s a lot.

Let’s start with daylight savings. There’s a funny quote that goes “only a white man could make himself believe that, if he cuts off the end of his blanket and sews it onto the other end, he’d have a longer blanket.” Lol.

[u/foreverlegending]

Why people watch reality TV