Simple Simon
Simpleton
Well, yes - but in fact you can take any shape and just set the matrix so that the parts that are there in the shape you use and should not have a density of 0
Science & Technology Quiz 2: The one with the catchy title.
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Well, yes - but in fact you can take any shape and just set the matrix so that the parts that are there in the shape you use and should not have a density of 0
Perfection
The Great Head.
So in other words, gravity.
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Principle, not force.
One answer would be Entropy. Moves to an overall lower-energy state, which will have higher entropy.
First you try to nitpick, and then you make a statement that violates two laws of thermodynamics? Violating one law of thermodynamics is usually bad enough in phyics, but two? In one sentence?
Back to the topic: Anyone up for answering my question, or should I solve and leave an open floor? (I guess I should avoid quantum mechanics questions in the future)
I will solve then:
A density matrix is a statistical representation of a quantum mechanical state. It is sufficient to fully characterize a state.
The density matrix does not only contain probabilities in the main diagonal elements, but also phase correlations, which can be extracted from the other elements.
An advantage of a density matrix over a wavefunction is, that you can actually measure the density matrix.
Open floor.
A density matrix is a statistical representation of a quantum mechanical state. It is sufficient to fully characterize a state.
The density matrix does not only contain probabilities in the main diagonal elements, but also phase correlations, which can be extracted from the other elements.
An advantage of a density matrix over a wavefunction is, that you can actually measure the density matrix.
Open floor.
GoodGame
Red, White, & Blue, baby!
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Leptin's are hormones that signal the body to metabolize fat stored in fat-cells.
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It is a system that is out of equilibrium, and spontaneously moves to an equilibrium. Isn't that an increase in entropy?
No idea how or if entropy is defined in a non equilibrium state, but you wrote something about a low energy ground state which apparantly has a higher entropy. That part is definately wrong.
Formulated that way it makes more sense, but we only get increased entropy because of the assumed friction. The actual downward motion doesn't increase entropy at all (easiest way to see this: imagine no friction and a spring that counteracts the downward motion. In that case it would be fully reversible and a reversible process means the entropy cannot change). Thus it cannot be said, that entropy is causing the motion. The entropy is only responsible for stopping the motion in the balanced posiotion.
There were two fundamental things wrong with your original statement: First, there is no overall lower energy state. Energy conservation (that's what the first law of thermodynamics means) is one of the fundamental principles of physics. Thus overall energy cannot decrease.
For open systems, energy can decrease. However, systems in a lower energy state have less entropy instead of more. If you cool something (so that it has less energy than before), you decrease the entropy and you will need to increase the entropy of something else. If cooling something would increase the entropy of a system, the released energy would be basically free. We could extract huge amounts of energy from the oceans by cooling it down, if it wasn't for that pesky second law of thermodynamics.
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My view, as noted, was that it was a spontaneous process. The potential energy of the weights get converted to kinetic energy as one side moves down, and the other moves up. The reason that this doesn't go on for infinity (oscillating) is friction. This friction is energy lost from the system (depending on where you draw the system boundary - as you note, energy is not actually lost from the universe, but it is lost from the balance scales).
I do agree that it is not actually entropy causing anything. A change in entropy is the result of a process, but a spontaneous process cannot happen without a positive change in entropy.
...Without a change in energy over the system boundary. See above.
Entropy of the universe, yes. I was being disingenuous (at best) and just confusing myself (at worst): Overall, energy is conserved. Energy of the scales decreases (heat loss), but entropy of the universe increases. I was, in effect, claiming one effect on an open system, and another on a closed system, yet implying they were the same.
That may be roughly true, but I'd want the mechanism for the signalling, and it's not leptin's most important role anyway.
Do you remember how it was discovered?
Well, it's been well over 72 hours since the question was posted....
who's going to ask the next one?
who's going to ask the next one?
Perfection
The Great Head.
How many atoms are in my root beer bottle right now?
Hint:
Edit: Don't forget to show your work!
Hint:
Edit: Don't forget to show your work!
Zero, you are sad because you drank it all.
GoodGame
Red, White, & Blue, baby!
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How many atoms are in my root beer bottle right now?
Hint:
Edit: Don't forget to show your work!
I typed in Google "atoms glass bottle Perfection" but it didn't give me those conversion rates like normal
My turn: "How many liquids are in Perfection's glass bottle?"
Glass isn't a liquid, so if the bottle's truly empty, then none. However, I can't imagine that there wouldn't be some teensy-weensy bits of water (or sugar solution, more likely) clinging to the im-perfections on the inside of Perfection's bottle. So I'm going to say at least 1
Mise
isle of lucy
Well it'll still have air in it 
unless we assume a spherical cow in a vacuum.
unless we assume a spherical cow in a vacuum.
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