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Ask HN: What scientific phenomenon do you wish someone would explain better?

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Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#661

Post by SuoDuanDao »

jddj wrote: post #640
sideshowb wrote: post #637

Earlier quoted context omitted.

Whoever defaulted spent the money on something else, so it's still in circulation somewhere, just not in a form the original creditor can get hold of.

That would be my intuition too. But if you go down almost any "this crisis won't cause inflation because..." rabbit hole on hacker news, you should see multiple unopposed claims that defaults lead to deflation through the destruction of money. I'm pretty ignorant in this field, and usually I've been a day or so behind the posts (missing the window to press for more information), but I feel like there's definitely som…

Here's how I would think of that:

Suppose I'm a bank, and I lend you $10 to buy apple tree seedlings. You spend all $10 on seedlings as promised.

The person who sold you the seedlings has $10. You have the seedlings. I have an expectation of getting $10 in the future, presumably from your sales of apples.

Because most people repay their loans, I'm confident I'll get the $10 back, and being a bank, my business is lending money. I might treat the $10 loan as $7 on my balance sheet when I decide how much money is safe to lend out.

Then the price of apples crashes. You come to me and say, 'look, there's no way I'll make $10 selling apples in the time I promised to repay you. Best I can do is deliver you the seedlings or sell them to my neighbor for $3 and give you that'. I grumble a little, but take your deal.

The person you bought the seedlings from still has $10. Your neighbor now has the seedlings and $3 less. I now have 3 real dollars instead of 7 hypothetical dollars. In other words, 4 hypothetical dollars disappeared. When I decide how much to lend out, I'll be basing that on $3 I know I have, instead of the $10 I thought I'd probably get back. I don't lend as much money to aspiring orchardists (orchardeers?), and the price of apples rises.

Edit: This fragility is probably a major factor why some people are so against fractional reserve banking (my counting hypothetical dollars as having value) but without that hack, there's no saying I could have lent you the original $10, so it's a bit of a double-edged sword.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#662

Post by mncharity »

tomp wrote: post #76

Flight. Apparently "air flows faster on the top side of the wing, lowering the pressure" is an incomplete explanation; I even heard we don't completely understand why it works (?!?).

One concept is "heavier than air" flight is throwing air downward.

Visuals help: [1] https://aviationphoto.org/wp-content/uploads/2016/11/Paul-Bo... [2] https://www.popphoto.com/sites/popphoto.com/files/import/201... [3] https://imgur.com/gallery/EHW7D [4] https://www.youtube.com/watch?v=dfY5ZQDzC5s&t=192

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#663

Post by caf »

jddj wrote: post #636
rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

I've wondered the same thing lately whenever someone here posits that defaults cause the destruction of money. I'd love to see this properly explained, because it definitely has a counter intuitive ring to me.

It works like this: imagine we create some new Bank. Customer A deposits his life savings of 1 million hackerbucks.

Now our Bank loans out 50,000 of those hackerbucks to Customer B. It does this by crediting her account with 50,000 hackerbucks, but notice that Customer A still has 1 million in his account - so now there's 1,050,000 hackerbucks in apparent existence - we've created 50,000 hackerbucks from thin air. If Customer B withdraws the loan money to go spend it, the Bank will have 950,000 in reserves and an asset worth 50,000 (the loan). Customer B will have 50,000 in cash.

What we've actually done is increase the "M2", one of the measures of how much money is in the economy.

If Customer B either repays the loan or defaults on it, that new money disappears. In the loan repayment case, the Bank goes back to having 1,000,000 in reserves, and in the loan default case the loan asset becomes worthless and it is left with only 950,000 in reserves (the other 50,000 is out there with wherever Customer B spent it).

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#664

Post by Hongwei »

dmichulke wrote: post #648
rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

One approach is reductio ad absurdum: If Central Banks can create money without negative effects, then - why tax people? - why even work? Can't we just print enough money for everyone and live happily ever after? I realize these questions are quite provocative and their answering only explains if it will work but not how or when it will fail.

- why tax people?

So that common services (eg. healthcare in Canada, education everywhere, roads) can be collectively paid for.

- why even work? Can't we just print enough money for everyone and live happily ever after?

Because there wouldn't be enough resources. (Fiat) currency is just a medium of exchange for real stuff. Instead of growing wheat and trading it for your wooden furniture, the state provides a medium of exchange so we can both just transact in money. eg. when I don't need more furniture but you still need wheat.

Money =/= wealth

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#665

Post by nicoburns »

dmichulke wrote: post #648
rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

One approach is reductio ad absurdum: If Central Banks can create money without negative effects, then - why tax people? - why even work? Can't we just print enough money for everyone and live happily ever after? I realize these questions are quite provocative and their answering only explains if it will work but not how or when it will fail.

> - why tax people?

Printing money is actually more or less equivalent to a tax, because it reduces the value of the existing money supply.

> - Can't we just print enough money for everyone and live happily ever after?

No, because printing money redistributes wealth, it doesn't create it.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#666

Post by Davidbrcz »

keithyjohnson wrote: post #657

Agile, an empirical survey of whatever the hell it actually is.

Agile is a short-lived V cycle repeated for ever.

Legacy V-cycles (needs - spec - code - test - integration - product) were such that everything was written down and planned in advance for months/years. So, if the customer had made an error, his/her needs had changed... you were basically screwed.

Agile advocates for Short V cycles while getting often user feedback. But it's a V cycle.

- PO speaks to the customer = get needs - PO writes tickets, UX design something = specification - And then it follows the classical cycle : develop, test, integrate, deliver.

What's remain around agile (ceremonies & co) feel much more like bullshit to me, and people follow it religiously without understanding the core idea of agile as they think V cycle is an insult.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#667

Post by caf »

sideshowb wrote: post #637
jddj wrote: post #636

Earlier quoted context omitted.

I've wondered the same thing lately whenever someone here posits that defaults cause the destruction of money. I'd love to see this properly explained, because it definitely has a counter intuitive ring to me.

Whoever defaulted spent the money on something else, so it's still in circulation somewhere, just not in a form the original creditor can get hold of.

Sure, and that's just like a net effect of a gift from the creditor to the debtor, which doesn't have any effect on the money supply.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#668

Post by BiteCode_dev »

Relativity.

I just can't grok it.

I can't understand how time would flow differently depending of your speed.

I don't get why C is a constant no matter the referential, for any other object the speed is relative to your referential. I just don't see how those 2 are compatible.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#669

Post by jbanfill »

OkayPhysicist wrote: post #627
jbanfill wrote: post #446

I have wondered if heat and photons impart a partial charge on atoms and molecules which causes several phenomena. Faster Brownian motion due to the increased repelling action of stronger charges which cause pressure/volume changes in gasses. Also are these charges responsible for some weather effects such as the jet stream. In a tornado is the negative charges on the dry side of the dry line interacting with the moi…

Charge can be pretty easily shown to be a conserved, quantized value. So chargeless particals imaprting a partial charge would be a big no-no.

I didn't mean it was equivalent to the charge of an electron. What I was wondering is how do heat and light impart more kinetic energy to physical objects? Light may be the quantity of a photon but heat seems to be more of an analog property. And what are some ramifications of these energized particles in small spaces like enclosed gasses or large unenclosed spaces with effects like the weather.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#670

Post by Hongwei »

rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

The consequences are supposed to be inflation. Instead, we seem to only get asset inflation (houses, stocks) and not consumer goods inflation (flour). From a former econ prof who I spoke to recently: the central bankers aren't thinking about inequality or inflation right now, they're just trying to avoid the apocalypse.

The liquidity injected is supposed to be taken out later, thus removing the inflationary distortion. Whether it will or not is anyone's guess. 2008's injections have yet to be taken out.

Central banks are easier creditors because, while autonomous, they are the same country as the government! So it's technically like owing yourself money. A central bank that cooperates with the debtor country (itself) would never force a default, and is thus never an acute problem. Of course, infinite money printing should lead to dangerous inflation.

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