Vomiting is expelling digested or partially digested food.

Regurgitating is expelling undigested food.

Remember cows regurgitate so that they can swallow it again for digestion.

We aren't sure, and that's the only ELI5 answer that's possible.

Consciousness is a very complex topic both scientifically and philosophically. Can you even prove that I am conscious? Can you prove that your own mother is not just some automaton that responds to stimuli in a way you'd expect?

For a landmass of it's size, Africa has unusually linear coastlines with very few (compared to other continents) suitable seaports.

Maybe, maybe not. It depend on the situation and the people. At the end of the day, people don't need to justify their reason to not be friend with someone. They don't need a good reason outside of I don't want to be friend anymore. Without specific I can only answer vaguely.

Because aid doesn't work.

It's a scam.

People too weak to face the harshness of reality try to throw money at the problem to make it go away and stop hurting their fee-fees.

If it hasn't worked in the last 20 years - try something else.

Quantum computers are capable of taking encryptions that would normally take super computers 500 years to crack and crack them in minutes.

That said quantum computers are still so expensive and rare that you and I shouldn't be concerned about someone using them against us. They've already started development on encryption methods that use quantum phenomena to encrypt messages that even quantum computers have a hard time cracking.

As if the US does not have deserts and as if Afracia does not have jungles.

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It's what everything is made of and it's the only thing that exists.

That direction changing is it being affected by gravity. As a photon passes a star it's trajectory is changed. Not because the star is pulling on the photon but it has distorted space itself. In a black hole that's base is bent so severely that circles back in on itself.

You don't want to think of gravity as a force that is pulling on objects. But bending space. Earth isn't traveling in a circle around the Sun. It's traveling in a straight line. The sun has just bent space so that line circles back around in on itself.

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A flame is the result of combustion and it needs a fuel and an oxidizer.

The oxidizer is usually oxygen and there the atmosphere is 21% oxygen.

The rest of the atmosphere 78% nitrogen 1% argon and 0.04% other gases. Neither nitrogen or argon can be the fuel and burn with oxygen.

If we list the other gases in how common the are until we get one that can burn: Carbon dioxide, Neon, Helium and Methane.

Methane is the most common gas in the atmosphere that works as a fuel and its concentration is 0.000187% That is simply not enough to sustain combustion and even if it was possible you only use need a bit less the 2/3x the amount of oxygen. The result is 0.0005% of all atmospheric oxygen will be used up when all methane has combusted.

People don't realize how damn big Africa is. Thanks to the Mercator projection, a lot of people think it's smaller than Greenland.

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we dont know yet. we cant understand what consciousness is.

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there has been some nuance in and out of mindfullness and eastern meditation.

but, science hasnt been able to measure it, so its still a decentralized term

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there is the classic nature nurture dynamic at play. which can shape your conscious awareness. but we arent really settled on that definition.

In metaphysics, there has been theories to help explain adjacent-phenomenon related to universal theories:

IE, string theory, quasi crystals/8 dimensional theory, etc. But these are all theories, mostly based on mathematical models.

I like what Vonnegut said about humans, frankly. We dont have any absolute answers, and we are all just here to fart around

That is incorrect. The light does actually slow down without getting absorbed or bouncing.

What is important to understand is that a photon is the oscillation of the EM field, not just a particle. Charges (like an electron) interact with the the EM field both eays, they are acted upon and act on it. Oscillations cause charges to move, but moving charges cause oscillations in the field. These effects interact with eachother in such a way that it causes the oscillation (a photon) to propagate slower in that medium than the maximum speed (speed of light) even without being absorbed.

The way you're describing it, transparency would be impossible, everything would be translucent or opaque. Like, say, the core of the sun that you mentioned.

The top part of the response is the most accurate. Work in the medical field long enough and you see what happens to "conciousness" when parts of the brain are impaired, begin to break down, malfunction, or were simply lacking to begin with.

It's all an illusion, a rich tapestry woven by the brain, and in the grand scheme of things it doesn't take much to strip us of it.

>we don't even know what it actually is let alone how it works

That's the core issue. Until you define what conciousness actually IS (and by "define" I mean in scientific terms that could in principle be used to make testable predictions, not in untestable philosophical generalities and ambiguities), it's redundant to attempt an explanation; you're just playing with words and hoping that nobody notices. Personally, I feel it's strongly connected to (in a complex organism may even be equivalent to) a complexity of brain function that allows it to observe and consider what and how it is "thinking" - to include at an adequate level its own "thought processes" as input data, in other words. That seems to me to be pretty much where the existence of a sense of "self" has to start. But that's just my two penn'orth.

("Brain", "organism" etc. here being simple shorthand - I'm quite comfortable with the prospect of, say, a non-organic mechanism having conciousness. Again - until you define what that IS, you most definitely can't exclude possibilities based on what feels suspiciously like pure anthropomorphic prejudice. Oh - and given the number of rather capable AIs suddenly out there - we could probably do with something approaching a definiton quite urgently. Just saying...)

(I have a similar definitional issue with "free will". Define it (in purely scientific, non-"spiritual" terms) - show me what it might actually mean scientifically for a mechanism or organism to have "free will" - and we can start talking sensibly about it.)

Yup that's why there's no "make a back door just this one time so we can stop the terrorist".

It's all or nothing. The backdoor is wide open for everyone, or for no one.

Because the flame doesn't only need oxygen. It also needs fuel to react with that oxygen and it needs the reaction of the fuel with the oxygen to release energy overall.

When you are burning something in the air, you're burning something -- that is, a fuel. The reason all the nearby stuff doesn't catch on fire as soon as you strike a match is that all of the nearby stuff doesn't react with oxygen in the air in a way that releases energy unless it gets hot enough, and it isn't hot enough. Of course, if it's close enough to a flame, then it too can burn because the flame is heating it up to a temperature where it will react with the atmosphere.

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Military war games often don't involve actual combat, instead being either computer simulations or tabletop exercises intended to test out hypothetical scenarios with something similar to the d20 system being used to determine outcomes. While it may be hard to believe, these kinds of exercises can produce valuable insight into what might happen during a conflict, and some countries have paid a steep price for ignoring the outcome of a tabletop war game.

One of the most famous examples of this was in the Pacific theater during World War 2. Shortly before the Japanese launched their attack on Midway, their military leaders held a tabletop war game where they did a test run of their attack plan. The outcome of the exercise was a decisive American victory. The Japanese naval leadership dismissed the results as implausible and proceeded with their plan, only for the events predicted by the war game to play out in real life.

Because a flame needs two things to burn:

Oxygen and fuel. And the rest of the stuff that's in the air (mostly nitrogen) doesn't work as fuel, so the air by itself can't burn.