The expansion is not the kind of expansion you're thinking of. It isn't like a sphere getting bigger. It's more like every ruler in the Universe is getting smaller, so all measurements of distance stretch to be longer even though nothing "really" moved.

There is, as far as we are aware, no edge to the Universe even if it turns out not to be infinite (which current evidence suggests that it probably is). If the Universe were finite, it would be more like the surface of the Earth where you could get back to where you started after going "all the way around".

Well, not specifically sour patch kids (they're flavored with citric and tartaric acid, not ascorbic [which is vitamin C]), but yes.

And, realistically, most Americans aren't deficient in Vitamin C anyway. It's found in all sorts of foods to add a sour flavor - a pack of your average sour candy is several day's worth of RDI.

There are not 4 weeks in a month. 4 weeks is 28 days, which is a bit less than every month except a non-leap-year February.

A closer estimate would be 4.5 weeks in a month, which would be $45 a month times $12 = $540, fairly close to your (correct) $520 computed by just using the number of weeks in a year. (Although, strictly speaking, there are 52 weeks + 1 or 2 days in a year, depending on whether it's a leap year.)

OP might be confusing a high elastic modulus with a high [yield](https://en.wikipedia.org/wiki/Yield_(engineering)) point. In this case, since wood is a relatively stiff material, it will yield long before it deforms by very much (here's a table with yield strengths for wood boards).

To rephrase for OP: the elastic modulus tells you how much wood deforms, but it doesn't tell you anything about when it will bend out of shape permanently or break. A wood board can't support 450 cars, but not because it gets squashed, because the load exceeds the yield strength of wood.

Are you talking about the "leftover" spots after you look away from the bright thing?

The technical term for this is an afterimage. It's mostly caused by your brain compensating for the bright stimulation of the light. Basically, your brain is looking for contrasts, and it assumes that most of your visual field "should" be at a similar brightness, so it adjusts very bright spots down in brightness in a way that lingers for a short time. (Another, smaller, contributor is that the cells in the retina - the light sensitive part of your eye - can only be stimulated so often, and a very bright light can easily saturate all of those cells so that they're effectively "disabled" for a few seconds.)

It is, formally speaking, a different unit. But for our purposes here on the Earth, where the vast majority of practical use of the units is conducted, the two are proportional and that proportionality is constant enough for the difference not to matter.

Ultimately, yes: all of Earth's atmospheric oxygen is from photosynthesis. But in the more local sense, it's just dissolved into the water from the air around it.

> Whether the die is weighted towards a 6 or not, the individual rolls are still independent from each other, merely the probabilities of the outcomes are different.

The rolls are, but provided you have any uncertainty about the underlying probabilities, your beliefs about those rolls (and your expectations about the future rolls, which is the exact same thing) should be updating with each roll.

For a simple example, imagine I have two coins. One is loaded to always land heads, the other is fair. I pull one of the two from a box at random, and I do not know which I pulled. I want to estimate the probability of my next flip being heads. It's 75% in this case (50% to be loaded * 100% if it's loaded + 50% to be fair * 50% if it's fair).

I flip the coin, and it lands heads. This is evidence in favor of me having the biased coin. Specifically, I should update my probability that the coin is biased (using Bayes' rule) to:

P(loaded | heads) = P(loaded and heads) / P(heads) = 0.5 / 0.75 = 2/3.

Now I want to estimate the probability of the next flip. There is now a 2-in-3 chance (or more properly, that is my correct Bayesian estimation of that probability) that I am holding a biased coin, so the probability of the next flip being heads is 5/6 (it's 2/3 * 1 + 1/3 * 1/2 = 2/3 + 1/6 = 5/6). This is not equal to my original 3/4, even though the flips themselves are IID, because their underlying distribution depends on an unknown parameter about which I am gaining information.

Yeah, pound is a mass unit, but we treat it as a force unit via the [pound-force](https://en.wikipedia.org/wiki/Pound_(force)).

> Didn't the government "print" lots of money for covid benefits?

The current episode of inflation started well after those policies had mostly ended.

Remember, "inflation" is just a term for "a general rise in prices". And there are obvious reasons for such a rise:

• Supply chains were badly disrupted during covid, and remained so into 2022 in part due to China's aggressive zero-covid policies. And since supply chains have many steps, it takes a long time for those effects to work their way through the system: a shortage of metal today might mean a shortage of lumber tomorrow if the lumber supply depends on, say, being able to buy more chainsaw blades.

• Wages have risen [though not as fast as inflation] due to a hot labor market, which in turn is due to a combination of retiring Boomers, a non-trivial chunk of the population being killed or crippled by covid, and a culmination of existing trends in labor movements.

• Rising wages did create some increase in the money supply.

• Energy costs are pretty high. This was especially true in the immediate aftermath of the Russian invasion of Ukraine, which caused a big disruption to energy markets.

• All of this created an environment where profiteering was easy and could be blamed on "inflation" without brand damage. Fortune 500 companies posted record profits in that environment by considerable margins, even in real (inflation-adjusted) terms. A quick look at their list shows us that 200 of the Fortune 500 had their profits double or more in 2022, and many more posted growth far far above inflation.

I am not enough of an economist to tell you which of these is most important (and given the general voodoo that is economics I'm not sure I'd trust actual economists to say with that much confidence either), but at the very least there's plenty of alternatives to covid-related money supply.

The federal reserve lends money to banks. Banks can, and do, borrow massive amounts of capital from the Fed, which they use to lend money to everyone else. Generally speaking, bank-to-everyone-else loans have a higher interest rate than fed-to-bank loans (since otherwise the bank is losing money acting as a middle-man).

By raising their interest rate, the fed makes borrowing from them more expensive. That reduces the amount banks borrow from them to re-loan to others, which in turn reduces the money supply - the availability of money as opposed to other goods - in the economy as a whole. Since high money supply is one cause of inflation, this can help reduce inflation through government policy. (The current episode of inflation is pretty weird though, and only loosely caused by money-supply issues.)

The insight here is that, provided you are not certain of the fairness of the die, each roll would give you information about its fairness (and therefore about future rolls). The rolls themselves are still independent even on an unfair die, but you will develop progressively better estimates of the actual underlying probabilities.

(Of course, in basic statistics we ignore this sort of thing and just assume the die is fair or loaded in some known way. But this is an important caveat in real-world statistics!)

> There's nothing connecting one roll to the next; they are completely independent.

...under the assumption of a completely fair die. (An assumption you are usually making in a statistics class.)

In practice, though, the fairness of the die may be in doubt in many real-world scenarios.

Or, more simply put: the world is very, very big.

They're from different languages.

a- meaning not is from Greek, and is usually attached to other Greek roots: atheist (from Greek theo "god" as opposed to Latin deus), anoxic ("oxygen" is from Gree roots), etc.

ab- meaning "away from" (as in a direction, the opposite of "towards") is Latin, and is usually attached to other Latin roots.

During the explosion, each fission event causes >1 additional fission events. Let's say it causes 1.1 more.

As a rough rule of thumb, if something is increasing by X% per step, it doubles in 70/X steps. So in this case, at a 10% increase per step, it doubles every 7. And since each step here takes a tiny, tiny fraction of a second, this doubling can happen many, many times within a slightly less tiny fraction of a second. A rough estimate for the step time here is about 10 nanoseconds (that's 1/100 million of a second), so you're doubling in less than 100 ns, you've doubled more than ten times within 1000 ns = 1 microsecond, and you've doubled more than a hundred times within 10000 ns = 10 microsecond. (It turns out that you don't actually get this far, for reasons we'll see in a second.)

If you naively continue this process) you've doubled more than a thousand times within 100 microsecond (= 0.1 millisecond). 1000 doublings is 2^1000 = 10^300 or so. Since there aren't even 10^300 atoms in the entire Universe, this obviously can't be the case. In fact, even 2^100 = 10^30 or so is beyond the number of atoms in a supercritical chunk of normal nuclear materials.

But nothing about our math is wrong here. Instead, something must be wrong with our assumption that this process continues the way we've modeled it here. And the reason it doesn't - and hence the answer to your question - is that the developing nuclear blast starts to split its fuel apart. To make it explode in the first place, you needed to compress the fuel into a small area, so that the neutrons emitted by each fission event can be captured by other atoms of your fuel. Once the fuel isn't compressed into a small area, the number of fission events caused by each fission event (our 1.1 above) goes down, and we can no longer model the explosion's progress as a raw exponential curve. Once it falls below 1, the reaction starts to slow, and if it's much below 1, it slows down quickly.

In practice, once it is below 1 in a nuclear explosion, you've already got a very violent explosion blasting the fuel apart. So it very quickly drops far below 1, and any energy release past that point isn't caused by the initial chain reaction. This isn't quite the end of the the energy release, since the decay products from the initial chain reaction are also exceptionally radioactive and themselves quickly decay, but even those quick decays are minor-ish contributors to a nuclear explosion because their time frames are much longer than the duration of a nuclear blast (usually, anyway).

They're being exposed to bacteria that are already present in your lower digestive tract. Those bacteria can be harmful if you eat them (fecal-oral is a very common way that food poisoning bacteria spread), but they're not dangerous in your intestines or (directly) dangerous on your skin (except that having them on the skin of, say, your hands can be a good way to end up with them in your mouth).

Added a note at the top of my post. Thanks for the correction.

EDIT: as /u/mfb- notes below, these numbers are off by a factor of 10 - all these percentages should be one decimal point to the right (e.g. 0.2% -> 0.02%).

Yes. Most of the CO2 was made by burning carbon-containing molecules using oxygen from the atmosphere, so each CO2 molecule roughly corresponds to one less O2 molecule.

But since CO2 is a small portion of the atmosphere's total, this doesn't make a big difference. Today, CO2 is about 420 ppm, or about 0.42%, of the atmosphere; prior to humans it was about 280 ppm (~0.28%). That's a huge difference in terms of how much CO2 there is; there's almost 50% more today than there was a couple centuries ago. But it implies a change of only about 0.14 percentage points in the oxygen amount.

Since oxygen is about 21% of the atmosphere, that's a relative change of only about 1 part in 150 of the oxygen content, which isn't a big deal. Air pressure already varies by more than that (it's the equivalent of about 7 mb of pressure, roughly the difference between a mild storm and a clear day) as weather systems pass by, so your body is already well-adapted to handling such small changes in oxygen content.

(Actually, I wonder if typical sea-level pressure is a bit higher today than it used to be. CO2 is heavier than oxygen, so the atmosphere should "weigh" slightly more than it used to - by a factor of, give or take, about 0.07 ppt. That's not nothing! It should correspond to a global increase in surface atmospheric pressure of about a millibar, which should be detectable. [EDIT: okay, a tenth of a millibar is less.])

Notably, though, this is a definition of convenience, since man-made materials absolutely can show the same properties that natural minerals do, and be studied with some of the same tools.

To a point. Some minerals form a series where, for example, you might replace aluminum with magnesium or whatever. But a mineral by definition has to have a specific composition or range of compositions. That's what distinguishes it from a rock (which is a collection of [possibly many different] minerals).

More simply: a fission reactor is designed to artificially increase (EDIT: decrease - rate go up, half life go down) the half-life of materials by a factor of a million or so, so as to release millions of years of potential decay in just a few years. It does this by using one decay to trigger another, which triggers another, and so on.

Expansion of the Universe aside, the size of the observable Universe (the only "size of the Universe" we can really observe) is approximately the age of the Universe times the speed of light. (Expansion has increased it well beyond this value - it's about four times that - but it's still on roughly the same order of magnitude.) So a simple answer to your question is "the Universe is old, so light has had a long time to travel, so the most distant parts we can see are very far away".

I regret to inform you that the Nevada desert is at an elevation of about 4000 feet.