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here's a comment addressed to me regarding a comment I left on meta:

AlfredCentauri, "...however, an adult, scientist or not, will hardly be humiliated by something so trivial..." That sounds rather hypocritical from you: have you forgotten some questions: this, and just recently: this, etc..? If you think it is not humiliating, and if you are an adult, why do you delete your answers were they are downvoted? - GreenRay

Heh.


1h
revised Do photons lose energy due to gravitational redshift? If so, where does the lost energy go?
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1h
comment Do photons lose energy due to gravitational redshift? If so, where does the lost energy go?
@innisfree, according to this paper: arxiv.org/pdf/physics/9907017 , the answer to the OPs first title question is no, the observed gravitational redshift is due to higher clocks running faster while the photon energy (and frequency) are unchanging with height.
5h
comment Can I become an engineer and a physicist?
Heh, I suspect the idea for this question started with someone saying "wanna watch some physics guys heads explode?"
11h
answered Position space wave function of an electron
1d
comment How can 99% empty matter have solidity?
201044, take refuge in the fact that others before you have asked essentially the same question and, I presume, you won't be the last. Voting to close...
1d
comment Back EMF in an electric motor
@Floris, well I think it's time for another drink. Cheers!
1d
comment Back EMF in an electric motor
@Floris, to be sure, I was addressing Alberto, not your comment. Let's see... yes, broadly speaking, we're both challenging the "suppose A is not A..." type of hypothetical.
1d
comment Back EMF in an electric motor
Honestly, I think the correct answer is "it wouldn't be a DC electric motor". If one simply uses the formula for mechanical output power, zero back emf implies zero output power which simply means the input electrical power is not converted to mechanical power, i.e., it's not a motor.
1d
answered Do photons lose energy due to gravitational redshift? If so, where does the lost energy go?
1d
comment How can matter reach the singularity of a black hole if time stops at the event horizon?
Indeed, black holes are like Vegas.
1d
comment How can matter reach the singularity of a black hole if time stops at the event horizon?
@JohnRennie, that sure is a shiny gold badge you've got there. When did you get that?
1d
revised Is the lay explanation of the equivalence principle wrong?
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1d
comment How can matter reach the singularity of a black hole if time stops at the event horizon?
"but which wasn't affected by the gravitational force" - since gravity is the curvature of spacetime, such a particle would necessarily 'ignore' the geometry of spacetime and that would be far more bizarre than a black hole.
1d
comment Does the velocity vector always point in the same direction as the momentum vector?
@yuggib, I've edited my answer to address your comment.
1d
revised Does the velocity vector always point in the same direction as the momentum vector?
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1d
comment Does the velocity vector always point in the same direction as the momentum vector?
@yuggib, good point about canonical momentum.
2d
comment Basic physics everyone should know
FJam, as a graduated student, surely you know that the answer is yes. But, this site is for questions related to a specific physics concept. A quick search on Amazon or Google will give you more resources for basic formulas and physics than you can possibly choose from. If you're asking for a specific recommendation, that is likely to generate too many different answers to be useful. Have you considered Kahn academy?
2d
answered Is the lay explanation of the equivalence principle wrong?
2d
answered Does the velocity vector always point in the same direction as the momentum vector?
2d
comment Is the lay explanation of the equivalence principle wrong?
A reading assignment: mathpages.com/home/kmath622/kmath622.htm