Science questions not worth a thread I: I'm a moron!

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Probably not that much to look at anyway. Just give me a straw I'll be OK.

I'll need some bags of crisps, nuts and a large supply of kebabs too.
 
Take a course in formal logic and foundations of mathematics (Peano arithmetic is a good place to start).
 
Formal logic just makes mathematics into a game where soundness need not have any place. This works fine for computational systems and those sorts of perspectives on mathematics (regarding calculation as fundamental in mathematics comes as a very quaint, romantic notion, Peano wrote in Latin, and probably comes as the last serious scholar to write in Latin). They may prove THAT 2+2=4, but it doesn't really work though if one asks "WHY is 2+2=4?" Why does it really need an answer? If we didn't have some questions necessarily open, what room would exist for others to grow, create, etc. for themselves?

I think that 2+2=4 helps mathematicians to survive as mathematicians and to reproduce mathematics. Otherwise too many people would think it awash in nonsense and no mathematical scholarship could or would ever happen. But, what do you think Quackers?
 
1) The universe is expanding, and the expansion is accelerating because dark energy is overcoming the force of gravity.

2) Some think that at some point, gravity will overcome dark energy and the universe will shrink towards a "big crunch."

3) Looking at the expansion of the universe, going backward in time takes the universe to a singularity...

Why does the universe get that far, to a singularity? Why wouldn't it just shrink to the point dark energy overcame gravity again? the way that gravity will overcome dark energy in the big crunch scenario?

EDIT: And why wouldn't gravity and the other forces reach an equilibrium at some point?
 
Pete Atoms said:
1) The universe is expanding, and the expansion is accelerating because dark energy is overcoming the force of gravity.
Click to expand...

Not exactly. The universe is expanding, because energy makes the universe expand. The dark energy is zero-level energy that exists even in the vacuum. It causes the universe to expand because the universe has huge empty spaces.

Pete Atoms said:
2) Some think that at some point, gravity will overcome dark energy and the universe will shrink towards a "big crunch."
Click to expand...

This is quite unlikely as far as we know today.

Pete Atoms said:
3) Looking at the expansion of the universe, going backward in time takes the universe to a singularity...

Why does the universe get that far, to a singularity? Why wouldn't it just shrink to the point dark energy overcame gravity again? the way that gravity will overcome dark energy in the big crunch scenario?
Click to expand...

We don't know what exactly happened at the big bang or how small the universe was. But in general, dark energy is proportional to the size of the universe and it isn't conserved. The universe is in many cases invariant if you swap t and -t, but the expansion of space violates this symmetry. The start state of the universe was not an equilibrium.

Pete Atoms said:
EDIT: And why wouldn't gravity and the other forces reach an equilibrium at some point?
Click to expand...

Again, dark energy is not conserved. We can't calculate how much vacuum energy a given empty volumen contains. When we try, we find it to be infinite. Still, we know it is there because of the Casimir effekt. General relativity predicts that energy expands space, but not how strong this effect is.
The Hubble parameter, which can be observed and which describes the expansion of the universe, is definitely not constant over long periods of time and we still fail to explain its change. You see, the universe is a weird thing. :p
 
Vacuum energy is quite different to the Casimir effects when we're talking about cosmology.

Casimir effects states that two plates very close to each other in a vacuum feel a force pushing them together (much much higher than that due to gravity). In short, it is because there are a limited number of quantum particles than can appear/disappear in the gap due to the restrictions on the possible wavelengths caused by the gap having a definite size. As such, there are more particles outside the plates then between them, and so a net pressure pushing the plates together.

Dark energy cannot be explained by this (as I recall, it is a factor of 10^100 out). We really don't have the faintest clue what dark energy, there are not even any good theories out there that tell us what it is - we just think it is somehow linked to the size of the universe. Or it could just be that general relativity is slightly wrong which would mean that we don't need a mysterious force to explain the rate of change of the size of the universe. This seems unlikely, but has by no means been ruled out.
 
Pete Atoms said:
1) The universe is expanding, and the expansion is accelerating because dark energy is overcoming the force of gravity.

2) Some think that at some point, gravity will overcome dark energy and the universe will shrink towards a "big crunch."

3) Looking at the expansion of the universe, going backward in time takes the universe to a singularity...

Why does the universe get that far, to a singularity? Why wouldn't it just shrink to the point dark energy overcame gravity again? the way that gravity will overcome dark energy in the big crunch scenario?

EDIT: And why wouldn't gravity and the other forces reach an equilibrium at some point?
Click to expand...

As far as I can see, the answer is "it's complicated." Explaining the (rate of) expansion of the universe is one of the most fundamental questions in cosmology right now. A lot of very intelligent people are thinking about dark matter and dark energy right now.
 
What would it take for a terrestrial planet to have quadruple the amount of lightning it has in an average storm than Earth has?
 
is there a phenomenom i'm not aware responsible for the food in a horizontal freezer to be colder on the top than at the bottom ?
 
Cold air is pumped in from the top?
 
Well, why do you think that this is true? I'd test it in my home freezer when I get back, but that won't be for about a week. Plus, I'm not sure that I have thermometers that go that low. But I'll try to remember to check.

It really could just be a perception bias sort of thing, where when your hands touch the food on the top level of the chest freezer the skin, which until recently has been in room temperature air, is shocked by the cold food. But after a few minutes of handling cold food, and being immersed in the cold air of the freezer, the skin of the hands doesn't sense the cold as quite as severe as it did at first.
 
Is anybody doing anything at all in lieu of actually trying to have a go at a space elevator?
 
Having read the article, he appears to start from the premise that you can use string theory and thermodynamics to explain the laws of thermodynamics without needing, space, time or gravity.

The article itself allures that he is probably a nut job.
 
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