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May
23
answered Is the preferred basis problem solved?
May
23
answered How do you come up with a POVM?
May
21
revised What is the general statistical definition of temperature?
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May
21
comment What is the general statistical definition of temperature?
Yes, but what if for example you have exact information about all the particles in your system (ie full momentum-position information), then temperature will cease to be useful. If you are lucky enough for the particles to be in the ground state then you can set it to zero, otherwise not sure how you can continue this representation.
May
21
comment What is the general statistical definition of temperature?
Thanks, updated.
May
21
revised What is the general statistical definition of temperature?
added 9 characters in body
May
21
answered What is the general statistical definition of temperature?
May
18
answered Is every quantum measurement reducible to measurements of position and time?
May
17
comment How do we simulate Nuclear explosion?
It's not necessarily a bad question, just needs to be clarified a bit. Are you trying to simulate the look of the explosion, the force resulting from the explosion, hydrodynamics of the surrounding atmosphere (and how far away are we talking?)? If you can clarify further I am sure somebody might be able to help you.
May
17
answered Definition of the entropy
May
17
answered Is decoherence even possible in anti de Sitter space?
Jan
14
comment Does conformal gravity explain the Bullet cluster lensing effects?
@zhermes Another question in this regard is whether it could be that the natural mass-energy distribution in the universe might not somehow lead to the same results anyway. Of course for consistency it must be the exact same distribution required to arrive at the rotation curves for galaxies, otherwise you have falsified the theory and you need to discard it. Is it inherently obvious why this scenario could not lead to the same results? (Sorry had to put it into two comments due to the space limit).
Jan
14
comment Does conformal gravity explain the Bullet cluster lensing effects?
@zhermes Yeah, that sounds very convincing. I can see how those locations would be natural if you just assume nice spherical halos. Consider the following question as a result of my lack of understanding of the dark matter models: Is there a standard dark matter halo distribution that applies to every galaxy or do you need to find it in each individual case based on the rotation curves and/or lensing data?
Jan
14
comment If quantum computation is reversible, what is the point of Grover's search algorithm?
You can invert it in principle but it could be very hard. That's the problem. Grover's algorithm makes it "easy".
Jan
14
answered If quantum computation is reversible, what is the point of Grover's search algorithm?
Jan
14
revised Does conformal gravity explain the Bullet cluster lensing effects?
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Jan
14
comment Does conformal gravity explain the Bullet cluster lensing effects?
@zhermes But does it really require that much of a conspiracy? The question here is really whether there is some fundamental reason why the preferred locations are special and we expect those exact locations to be preferred. You can equally consider the dark matter distribution to have conspired to produce those points, just as you can consider the universe to have conspired. On the other hand, perhaps we can consider it simply as a coincidence of either the dark matter distribution or the universe. Or did you have another reason in mind why this could be a conspiracy?
Jan
12
answered Why must quantum logic gates be linear operators?
Jan
11
comment Does conformal gravity explain the Bullet cluster lensing effects?
@ChrisWhite That is true. I can see how this can rule out MOND theories, where you change the potential in a classical (Newtonian) way. I think conformal gravity is a bit different in this regard, as here you modify action to be the square of the conformal tensor from the Ricci scalar, which changes space-time around a matter distribution in a way potentially dependent on matter outside the distribution of interest. It's not obvious to me that this could not effectively change the lensing effects to reproduce the apparent shift in the Newtonian potential. Can you explain more on this?
Jan
11
comment Does conformal gravity explain the Bullet cluster lensing effects?
So does that mean it is ruled out? From what I have heard, one of the reasons why conformal gravity seems to reproduce the dark matter rotation curve profiles is that the iron sphere theorem does not apply and that matter outside can contribute to the potential. Given that, is it obvious how this misalignment means conformal gravity is ruled out?