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I have went through a Thermodynamics Course, one of the best book which had used to clear my problem is: Thermal Physics by " Michael Sprackling" it describe the entropy in terms of both "Microstate" and "Macrostate". I have lot of doubts and which was very helpful for me


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Entropy Demystified (The Second Law Reduced to Plain Common Sense) by Arieh Ben-Naim. Authored discussed not only the thermodynamics origin of entropy but also the same notion in the context of information theory developed by Claude Shannon.


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So far there have been quite a few insightful answers about statistical mechanical entropy, but so far the only mention of thermodynamic entropy has been made by CuriousOne in the comments, so I thought it would be useful to give a short general reminder about the subtle difference between the notion of entropy in thermodynamics and the formulas that come up ...


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To be honest, I believe this question is not really settled, or at least that there is not yet a consensus in the scientific community about what the answer is. My understanding of the relation is, I think, slightly different than knzhou, rob, or CuriousOne. My understanding is that thermodynamic entropy can be thought of as a particular application of ...


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So Pratchett's quote seems to be about energy, rather than entropy. I supposed you could claim otherwise if you assume "entropy is knowledge," but I think that's exactly backwards: I think that knowledge is a special case of low entropy. But your question is still interesting. The entropy $S$ in thermodynamics is related to the number of indistinguishable ...


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Formally, the two entropies are the same thing. The Gibbs entropy, in thermodynamics, is $$S = -k_B \sum p_i \ln p_i$$ while the Shannon entropy of information theory is $$H = -\sum p_i \log_2 p_i.$$ These are equal up to some numerical factors. Given a statistical ensemble, you can calculate its (thermodynamic) entropy using the Shannon entropy, then ...


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Question 1 is based on the false premise that B measurement does not always obey a 50:50 probability. In fact persons A and B both always have a 50:50 probability of getting a spin up. That particles A and B are entangled means that there is a correlation between the measurements of A and those of B: when A is up, B is down; when B is down, A is up. But this ...


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Your question 1 has absolutely nothing to do with entanglement, and for that matter absolutely nothing to do with quantum mechanics. You can formulate exactly the same question this way: You and I each have in our pockets a tennis ball that is either red or green. We somehow each know for certain that they are of the same color (and that either color is ...


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What kind of information are we talking about in superluminal information transport? It might be more intuitive to call it superluminal communication. For the prohibited kind of superluminal information transport, you need to be able to achieve the following. At the start of the protocol, A holds a classical bit which either has value 0 or 1, and which is ...


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Leaving aside the issue of wavefunction collapse, physics is deterministic. So if you have some system like a gas and you know the exact positions and velocities of all the gas molecules you can predict the evolution of the system forwards and backwards in time. So you can start with a future state and work backwards to desciribe a past state. However ...


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Imaginary things can "travel" faster than light A shadow or a light spot can seem to travel faster than light, because it's not a particular physical thing, but a series of separate things, separate physical particles emitted at different time and at different locations. Imagine that you have launched a lot of tiny bots into space with a very accurate ...


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I think you've said a lot of things that are correct, you've just come to the wrong conclusion. You're right that that it will take us three seconds to SEE the shadow moving across the moon, because that's how long it takes the light to get there and back. But what we'll see is not the shadow slowly moving across the moon over a period of three seconds. ...


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It is known that moving a lantern will result in a spot or projected light that travels faster than light is the screen is far enough. However, this effect and similar ones do not refer to the motion of actual objects at faster than light speeds, nor this process allows transfer of information faster than light.



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