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Physics Stack Exchange users whose comments are worth studying include Lubos Motl and Ron Maimon (now at http://www.quora.com/Ron-Maimon and http://www.physicsoverflow.org/user/Ron+Maimon). Also see http://arxiv.org/abs/hep-ph/0207124 for a review of physics since the standard model.


Feb
5
comment Are the recently observed Dirac monopoles separable?
Why is it a major breakthrough?
Jan
28
asked Could sphaleron-induced proton decay also cause vacuum decay?
Jan
24
comment Why is the mass of a Kerr black hole proportional to it's angular momentum?
... and I would guess that the real answer may come from the holographic principle and the "Kerr/CFT duality", which is still a subject of research... I may try to turn all this into a proper answer.
Jan
24
comment Why is the mass of a Kerr black hole proportional to it's angular momentum?
But explaining the exact constant of proportionality may be more difficult. See the discussions at physics.stackexchange.com/questions/33473/… ... the explanations are a bit stiff and unilluminating, and the exact calculations only apply in the "weak-field" case. So there are mathematical depths here that are not yet understood...
Jan
24
comment Why is the mass of a Kerr black hole proportional to it's angular momentum?
As for why the Schwarzschild radius is proportional to the mass (and not e.g. proportional to some power of the mass), well, gravitational force is proportional to mass even in Newton's theory. It would have something to do with that, but expressed in the language of general relativity. Again, this deserves an exact answer...
Jan
24
comment Why is the mass of a Kerr black hole proportional to it's angular momentum?
As for the relation between mass and radius, the "radius" is the distance from the center to the event horizon, i.e. to the point of no return for objects that fall in, the place where the escape velocity equals the speed of light. If a black hole gains mass by absorbing something, its gravitational field will be stronger (because there is more mass) and it will get bigger, the point of no return will now be further out. So the radius goes up with the mass; it's directly, not inversely, proportional...
Jan
24
comment Why is the mass of a Kerr black hole proportional to it's angular momentum?
The mass and the angular momentum are independent properties. But there is a lower bound on the ratio (M^2)/J, below which it's not a black hole any more, because something that falls in isn't irreversibly trapped (no event horizon). It would have something to do with the twisting of space (frame dragging) due to the spinning, creating escape trajectories in this "overextreme" case en.wikipedia.org/wiki/Kerr_metric#Overextreme_Kerr_solutions ... The question deserves an exact answer.
Jan
21
awarded  Yearling
Jan
9
comment Why are cosmic conspiracies considered undesirable in quantum interpretations?
The basic objection is that such "conspiracies" evolve extremely improbable events. It's like the "theory" that there is no human being behind your posts, instead there was a cat walking randomly on a keyboard which by chance just happened to create meaningful sentences and post them to this site.
Dec
28
comment CP violation from the Electroweak SU(2)$_{weak,flavor}$ by $\int \theta F \wedge F $
See section 2 of arxiv.org/abs/hep-ph/9305271
Dec
6
accepted What is the experimental status of the G2-MSSM?
Dec
6
asked What is the experimental status of the G2-MSSM?
Nov
30
comment What prevents an atom's electrons from “collapsing” onto its protons?
The uncertainty principle prevents the innermost electron from simply becoming completely localized on top of the proton (because, if the electron is at rest, there will be a corresponding spread in its momentum values, translating to a spatial spread of its wavefunction), and then the other electrons are kept even further out by Pauli exclusion.
Nov
30
comment Proof that QCD is the theory describing strong interactions?
Some form of Regge theory probably holds true within QCD. But it would be a very technical topic.
Nov
29
comment One-loop beta functions of the Standard Model
What are "energy scale independent combinations of renormalization group equations"? Are they combinations of beta functions that equal zero?
Nov
24
awarded  Nice Answer
Nov
22
comment Reference request: Hollow concave Earth hypothesis
I suggest that you try to find a university library which has physical copies of that issue of the journal, and then find someone at the university who can photocopy the article for you.
Nov
21
comment How much of the mass of a supermassive black hole comes from dark matter?
The main DM debate over quasars seems to be whether they are located in the biggest concentrations of DM or not. arxiv.org/abs/1305.2199 says not... For the other view, look up "dark gulping" for the idea that supermassive black holes formed from DM.
Nov
21
answered How much of the mass of a supermassive black hole comes from dark matter?
Nov
19
comment What is weak interaction? I need easy and short answer
The weak force is a very weak force between left-handed particles, that can also transform them (electron to neutrino, or vice versa; one quark to another type of quark).