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To begin to approach quantum mechanics, you have to accept that on that very tiny scale, the world does not behave in a way that's intuitive to human experience. Everything you see and interact with as a human is in truth just some macro-scale approximation of an incomprehensibly number of complex relationships formed at unthinkably small scales. So with your human intuition set aside, you're ready to wade into QM.

For purposes of your question, it's probably best to start with the double slit experiment, which hails from the 19th century. I'll trim the fat to keep the ELI5 short, but definitely google videos about this experiment to gain a deeper grasp of what it shows and why that's important. But essentially, the double slit experiment shows that photons (light particles) can behave both as particles and as waves. Photons seem to act particle-like when you squeeze them through a narrow slit, but on the other side, it starts to interfere with itself in a wave-like fashion. This was puzzling, and took us a while to figure out.

In the 1920's, the Heisenberg and Schrodinger you've probably heard about got together and kind of cracked the code behind this strange quantum behavior. Heisenberg pieced together that there is an inherent uncertainty when you try to measure a particle's momentum and position. You can get an arbitrarily highly precise measurement on one of them, at a proportional sacrifice to precision on the other. This is the Uncertainty Principal. At the same time, Schrodinger developed his famous equations, which described quantum systems not in terms of discrete particles, but as single "wave functions." A wave function is sort of a probabilistic expression that describes all of the potential states a quantum system, accounting for this uncertainty. The wave function is a sort of sum of all these potential states, weighted by their probability. In that way, the wave function comes to approximate (very, very precisely) the "superposition" behavior of quantum systems, wherein the system behaves like a mix of all potential states it could take. Schrodinger's equations described how such systems evolve in this probabilistic fashion, and experimentation has justified him time and again.

Now, to return to your question, physics is much less concerned with answering "what things are" at a fundamental level and much more interested in answering "what things do." So we can only really answer the first question in terms of the second. To that end, we see that, at a fundamental level, the universe does not behave classically, but instead its constituent particles behave according to the everywhere-at-once oddity of QM. So we can say that fundamental particles are not simple points of mass or energy--they behave according to a much deeper and more vibrant structure.

You get it and live. It was not 100% fatal.

Additionally, if, say, 10% of the population is naturally immune, and you wipe out a third of the population overall with the disease, you end up with 15% of the survivors being naturally immune.

To add to the why question: The 1940s were a pretty terrifying time in human history. A few powerful countries were under the total control of people who believed their country was superior and had the right to overrun the world around them. Every major country was trying as hard as possible to make the most effective weapons to win the war. In 1941-42, it looked entirely possible that Germany was going to overrun the Soviet Union, murder or starve most of the people living in Eastern Europe, and be in an invulnerable position controlling Europe with an eye towards the Middle East, while Japan might control much of Asia. The idea of a bomb that could destroy a city looked like the one thing that could defeat Germany and save civilization. The U.S. and U.K. poured a lot of money and top scientists into it because it looked like a war-winner. (Fun fact: The project to develop the B-29 bomber, which dropped the first atomic bomb, was actually more expensive than the bomb project.) In the end, the Soviets fought like hell, the Western allies invaded as well, and Germany lost a conventional war, so Japan got bombed instead.

Thanks for the explanation, it was easy enough to understand. Now, is this why the Kaluza-Klein theory eveolved into string theory? Because the particles behaved more like vibrating strings than floating spheres rt?

How does the Higgs boson come into play here? Is it merely hypothetical or has it been widely accepted as something that exists? I recall several years ago there was a lot of hype because it was "observed" in CERN or something like that. What I can remmeber, it was the particle responsible for granting all sorts of matter their mass.

Doing some diving into wikipedia there are tons of things like gravitons and fermions and whatnot that make it seem like it's a massive iceberg out there. My question is, what is the most widely accepted theory for quantum mechanics and what subatomic particles have been proved to actually exist?

My very last questions:

1. Is it theoretically possible to split a subatomic particle? If so, how much energy would it release?
2. Is it true that many subatomic particles are believed to interact with parallel universes (like basically exist in both simultanoeusly)?

If I have the money on my account, why do I need to borrow it to show I can pay it back and am "trust worthy". If you have enough money in the bank and use it well and don't get in debt, doesn't it show that you are trust worthy? No you have to get in debt to show you can pay back debt.

The thing is that credit system is built so that you're forced to use it to show that you are reliable instead of it being something you have access to and can use every now and then.

you cant really keep them under control, this is a genie you cannot put back in the bottle.

one of the core reasons why they are " controlled" is because no single nation has a monopoly of them and said nations are adversaries, as a result of this knowledge all sides went to very extreme measures to ensure they can always retaliate against a nuclear strike as part of their doctrine.

this knowledge resulted in one of 2 principles that still hold ot this day that stop nuclear war : M.A.D.(mutually assured destruction) that dictates that unless you are fully capable of negating your enemy's ability to retalitate launching a nuclear strike is always gonna result in a phyrric victory where nobody wins.

the other principle is the knowledge that a nuclear conflict will stall the global economy meaning none of the interested parties make money anymore(if said parties discovered a means ot turn a nuclear exchange into a profitable thing, then we should all be very scared), this means there is a vested interest in preserving the status quo(ie: this is one of the suspected reasons the current conflict in easterm europe will likely not reach the nuclear phase.)

I wasn't really talking about acquisition. More so the use.

And that kinda feels like some bullshit that noone else has but hey the better. Point still stands, the main control is not wanting to be blown up aswel.

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> And keep them under control. Not at all.

Uh, the world has actually put a huge amount of energy into stopping nuclear proliferation (the term for new countries acquiring nuclear weapons).

Only eight countries are currently believed to have working nuclear weapons. In order of development, they are:

• the US (1945)
• Russia (1949)
• UK (1952)
• France (1960)
• China (1964)
• Israel (sometime in the 1960s or 1970s; unlike the other states on this list Israel does not admit that they have nukes)
• India (1974)
• Pakistan (1998)
• North Korea (2006)

(South Africa also once had them, and would appear on this list somewhere near Israel or India, but South Africa voluntarily disarmed and no longer possesses nuclear weapons.)

No new state has been added to this list in almost 20 years.

Literally HOW DO YOU BECOME IMMUNE TO THE BLACK PLAYUE

People either died or became immune. Eventually, plagues burn themselves out, running out of new people to infect and being eliminated in the bodies of both the survivors and the victims.

The main reason for the end of the black death was the implementation of successful Quarantines that allowed pockets of infection to burn themselves out.

But it didn't disappear overnight, numerous smaller local outbreaks continued for a long time after.

Improvements in overall hygiene, sanitation, and dealing with the rats is what eventually got rid of the Black Death for good.

Although it is still around today, just very uncommon. Modern anti-biotics and sanitation is what prevents it from being a problem.

Another working theory is that the Black Death killed off so much of the European population that those that remained living were the ones that had a degree of immunity or were more naturally resistant.

Yes. Not everyone who got the plague died, although a large percentage did (plague is fatal ~half the time without treatment), and there can be different degrees of spread for a particular plague epidemic.

A quantum particle isn't exactly a solid chunk of stuff. In some ways, it's more accurately pictured as a ripple in the fields that make up the universe.

It so happens that these ripples only come in whole-number sizes (they are "quantized") — so you can have no electron, or one electron, or two, etc., but you can't have half an electron or seven-fifteenths of an electron.

(That's what makes it quantum physics. In classical physics, there was never any rule that you couldn't split a chunk of matter down indefinitely. That turned out to just be wrong.)

What are "fields", though? A field is just some quantity measured at each point in some space and time. An example of a non-quantum field is the wind on the surface of a planet. The wind has some value at every point on the globe. (It might be zero, if the air is still.) And it changes over time. A breeze and a tornado are two different phenomena in the wind field.

(The wind is a vector field; at any point, it has both a magnitude and a direction. Air pressure and temperature are scalar fields; at any point, each has only a single numerical quantity. Gravity is a vector field; mass density is a scalar field. There are other more complicated kinds of field too.)

Why does it matter that particles are ripples and not tiny solid chunks? Well, one reason is that a ripple is inherently spread out, whereas a solid chunk has an exact single location.

And while solid chunks can only interact by bumping into each other, ripples can interact through interference — they can reinforce or cancel each other out. Solid classical-physics chunks can't do that.

(For another non-quantum example: Interference between ripples is also how, for instance, noise-cancelling headphones work: they make a sound wave that cancels out the noise.)

It's this interference that explains a lot of the "weird" effects in quantum physics, like the double-slit experiment. It's not that a particle "really is" a solid chunk that's magically in two places at once; rather, it never was a solid chunk at all, but a ripple that can interfere with other ripples, including its own echoes.

It took a massive team of over 100000 scientists, in something they named project manhattan. And its more so a why than a how. War is a good motivator to do a lot of stuff, the internet is due to war, commercial airplanes are due to war, etc. So they mostly just wanted a superweapon to wel 'nuke' the opposition into submission.

And keep them under control. Not at all.

The only reason noone is dropping them is because of a principal we call MAD(mutualy assured destruction) if you bomb someone you are sure as hell going to be getting one back because so many countries now have them.

As for why the full intensity didn't reoccur: the Black Death killed a third of the people in Europe (for comparison, that's about 100x the death rate of covid in the US), and infected most of the rest. By killing off the most vulnerable parts of the population, it made Europeans particularly resistant to plague, so future plague epidemics were less bad. It's similar to how modern Native American populations are no longer ravaged by diseases that, when their ancestors were first exposed to them, wiped out as much as 90% of the population.

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A few things:

• Knowledge has to be material, eg. significant to company's prospects/fortunes

• All trades by C-level execs, board members have to be reported, date and quantity

• There is a reason that shares are often granted by board at set times in lieu of top level people buying on open market

• Similarly, top execs often have set recurring sales set up for their spending, asset diversification purposes. So a CEO might automatically sell 1000 shares the Friday after each earnings call so it's easy to see that it's a recurring trade and not a sale because something is wrong

• Companies have "Quiet Periods" where employees, execs, board members, etc. CANNOT trade. These are in weeks leading up to quarterly earnings, before a major acquisition, before a major lawsuit concludes, and such.

People get infected by it in the present day.

Antibiotics help a lot, and we didn’t have those in the 1300’s.

Well, the point of the bomb part is you not keeping them under control.

How we did it the first time was decades of research from the world’s best scientists, starting with the basics of nuclear physics and how the different particles would interact. On top of that knowledge was a ton of engineering about how to manufacture the material components needed, including building an entire chemical processing plant at Oak Ridge, TN. Then it was experiments on the different shapes and components, and how to get them to work together.

Ultimately, the process is to take the fissile material and drastically compress it, turning it from merely dangerously radioactive to explosively radioactive.

Varying degrees of intensity? There are branches of severity in the Black Plague?

They're not "really" in two places at once. But, since we can't know their position and momentum at any given moment (only one or the other), we say that they have equal probability of being in multiple locations at the same time. There will be talk of a collapse of the wavefunction, which is what happens when a particle interacts with an observation, fixing its location for a time. In that instant of observation, it has a 100% probability of being where it is observed, but before that and after that, it can be anywhere in its' probability cloud. And that's what it is, too: a cloud of various probabilities for a particles location, some of which defy belief, but are nonetheless possible.

It didn’t, there were several so-called echo epidemics after that one. Later on, the disease did reoccur locally, with varying degrees of intensity

How long did you hold your finger in the screen?

How accurate was your click position?

Was it at several points, like a finger would, or a very tiny selected pixel?

All those are clumpt into human-like misses or bot-driven commands.