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Jun
13
comment Dimensionless Constants in Physics
Oops, you're right, of course, Frederic.
Jun
13
answered why the difference between $\langle \hat p^2 \rangle_{\psi}$ and $\langle \hat p \rangle_{\psi}^2$ is NOT zero?
Jun
12
comment How were the heavy elements from iron to uranium made?
Heavier elements came from dying stars etc. See this question and the first answers for the detailed nuclear processes by which various elements were born: physics.stackexchange.com/questions/3833/…
Jun
9
reviewed Approve Why did population III stars lack planets?
Jun
9
reviewed Approve Automated telescope system
Jun
9
comment Why is the mass of even the upper limit of the possible Higgs boson is less than the top quark?
More importantly, your comment suggests that you think that god particle gives mass to others "from a fixed reservoir of bread". But this doesn't work like this, there's no limitation on how much mass the particles may get. You're apparently taking the religious and kindergarten metaphors too literally, interpreting them in ways that have absolutely nothing to do with the physics and you had no chance to understand my answer. If I am right, you should give up studying particle physics because you're light years away from understanding even the high-school level of how particle physics works.
Jun
9
comment Why is the mass of even the upper limit of the possible Higgs boson is less than the top quark?
Dear Mr Ares, whether there is one god particle depends on the model and on the counting. Even in the Standard Model, the god particle comes from a "doublet field" that has 2 complex or 4 real components, 3 of which are "eaten" by others. In supersymmetric models, even if one only counts the un-eaten components, there are usually five god particles, motls.blogspot.com/2010/06/five-faces-of-god-particle.html
Jun
8
awarded  Constituent
Jun
8
awarded  Caucus
Jun
8
comment Who added $\frac{3}{2} \partial^2 c$ to the virasoro BRST current (and why)?
Thanks for your interest, Scott. No, unfortunately I don't know where it appeared first but it is really a straightforward 5-minute calculation. Let me also mention that the very appearance of some corrections of the form $\partial^2 c$ would be understood to be possible for decades - this expression may come from normal ordering of $\partial (bc)c$ terms because $bc$ may "cancel" (via their anticommutator which is a c-number) to another $\partial$. So this is just another case of a normal ordering ambiguity that may be chosen according to some more physical criteria - e.g. tensor character.
Jun
8
answered Why is the mass of even the upper limit of the possible Higgs boson is less than the top quark?
Jun
8
comment What is the Lie algebra of the Galilean group and what is the structure of it?
Yes, the Galilean group and algebra is a semidirect product. For each rotation $R\in SO(3)$, there is a 6-dimensional flat manifold, fiber, for which you have to specify the velocity $v$ for the boost as well as the extra absolute translation $a$. The translations and Galilean boosts transform as vectors under the $SO(3)$ rotations which determines the commutators with the rotations; the rotations don't commute with each other. Otherwise the translations and Galilean boosts commute with each other. A typical semidirect algebra which is less constraining than a simple group e.g. Lorentz group.
Jun
8
revised Who added $\frac{3}{2} \partial^2 c$ to the virasoro BRST current (and why)?
added 33 characters in body
Jun
8
comment Known properties of a specific class of quantum states
It's also important to mention that bits $x_i$ could be measured - all of them - by a single measurement of a classical computer. On the other hand, you can't find out all the values $x_i$ (and not even "most of them") by doing a single measurement on your state $\psi$. A single measurement of $\psi$ can give you at most $\log_2 n$ bits of information. Still, there's some literature about the "hidden matching", see e.g. scholar.google.com/…
Jun
8
comment Known properties of a specific class of quantum states
You may exponentially reduce the number of qubits needed for a certain number of bits but due to its unnaturalness, this formula isn't a helpful "proof" that a qubit is "exponentially more" than a bit. The right map is still that 1 qubit is a generalization of 1 bit and if they can be matched, they should be matched one-by-one. In particular, the reduced density matrix for a qubit may be calculated but it's just a gibberish function of the $x_i$'s. And other common operations with many bits $x_i$ would translate to unnatural, nonlocal, undoable operations with the fewer qubits.
Jun
8
answered Who added $\frac{3}{2} \partial^2 c$ to the virasoro BRST current (and why)?
Jun
7
comment Lacking of scale and distribution moments
Dear Emanuele, thanks for the report of a possible progress. There are no power law distributions on the whole positive real semiaxis because the integral doesn't converge for any exponent. Because the power law is the only distribution that is free of scales, it implies that any normalizable distribution has to have a characteristic scale, at least one.
Jun
7
reviewed Approve What is the minimum magnification needed for an instrument to see all the Messier objects?
Jun
7
reviewed Approve Video of Earth spinning?
Jun
7
reviewed Approve What are the minimum telescope requirements to view a nice spiral galaxy?