Apr
27
awarded  Caucus
Jan
10
awarded  Yearling
Jan
5
comment Lead catalyzed fusion
@cmaster I like this idea. Couldn't you reformulate your question so that it only asks for the cross sections, while not raising suspicion by a "fishy looking" (for some) fusion scheme?
Jan
4
comment Lead catalyzed fusion
I agree with cmaster that it is in fact in theory possible to take out energy (as you do indirectly fuse deuterium to helium) but it is still quite probable that one could not won back all the energy expended by the inefficient acceleration. And this idea lacks one of the greatest joys of other fusion schemes: the lack of permanents radioactivity (other than neutron activation)
2018
Dec
22
comment Why doesn't the escape of electromagnetic waves from a microwave depend on the reference frame, because of the Doppler effect?
Well, that makes sense.
Dec
21
answered Looking for redshift database or data
Dec
21
comment Mass distribution of a moving body
I do not doubt you know what you are saying, but I am a simple minded physics student and you insist using advanced notation to this trivial problem. It seems to me that my answer provides right what you are asking: The mass distribution as a function of time and the original coordinates.
Dec
21
comment Mass distribution of a moving body
@APC89 I must admit that I am confused with this domain D thing. For me it seems much easier to define m(r) for the whole space, or at lest for a domain large enough to enclose the whole trajectory.
Dec
21
comment Principle of etremal aging
I think that that the answer is that the principle relates to trajectories in spacetime. Even a stationary object "moves" through spacetime: it follows the time axis
Dec
21
comment Why doesn't the escape of electromagnetic waves from a microwave depend on the reference frame, because of the Doppler effect?
@MauryMarkowitz The question is not whether an imaginary person flying at relativistic speeds would see the microwaves. The real task is - that I have declared to be beyond my knowledge - demonstrating that even if you perform the calculations in a frame of reference moving at 0.999c relative to the owen you still get the correct result (that they can not escape)
Dec
21
answered Momentum of molecule after absorption of photon
Dec
21
revised Why doesn't the escape of electromagnetic waves from a microwave depend on the reference frame, because of the Doppler effect?
added a tag that seemed relevant
Dec
21
suggested approved edit on Why doesn't the escape of electromagnetic waves from a microwave depend on the reference frame, because of the Doppler effect?
Dec
21
comment Why doesn't the escape of electromagnetic waves from a microwave depend on the reference frame, because of the Doppler effect?
@SolomonSlow What you are saying is right, but there is more in this question. Per relativity, the same thing has to happen (either we can detect photons by a fixed detector in front of the owen or not), regardless of the frame of reference we are using. I hope that StudyStudy or someone else more well-versed in relativistic electrodynamics than me would write an answer.
Dec
21
answered Mass distribution of a moving body
Dec
21
comment Mass distribution of a moving body
Please edit that into question body
Dec
21
comment Mass distribution of a moving body
You does not provide enough information for this to be solved. Even if it is a rigid body (it does not deforms in any way), you need to know how it rotates.
Dec
21
comment Violating Newtons First Law!
whats the problem with my answer?
Dec
21
answered Violating Newtons First Law!
Dec
21
answered Trying to get moment of inertia of a disc using moment of inertia of a rod