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seen Mar 14 at 14:18

Jan
24
revised Significance of $\pi$ in physics
mention Newton's law
Jan
24
answered Significance of $\pi$ in physics
Jan
23
comment Locally flat coordinate and Locally inertial frame
Followup question: What happens if the observer is female instead? ;)
Jan
23
comment What is the significance of Planck's constant in De Broglie–Bohm theory or Pilot-wave theory?
it probably doesn't need to be said, but I'll do it anyway so no one else has to do it: as far as we know, there is no such thing as a smallest quantum of energy
Jan
23
comment Probability of spontaneous Boltzmann brain formation
everyone you observe is also one if you were a Boltzmann brain, there wouldn't be anyone else...
Jan
18
comment What kind of object is the Landau--Lifshitz pseudotensor?
the Landau-Lifshitz and Einstein pseudotensors are different objects, so you might want to edit your question to plural (or clarify in which one you're interested in)
Jan
18
comment Independence of thermodynamic variables
see also physics.stackexchange.com/a/160101/6389
Jan
18
revised Symplectic geometry in thermodynamics
added 190 characters in body
Jan
18
revised Symplectic geometry in thermodynamics
added 190 characters in body
Jan
18
answered Symplectic geometry in thermodynamics
Jan
18
comment Using Lagrangian mechanics instead of Newtonian mechanics
Newton only works in inertial frames while Lagrangian formulations work in arbitrary frames of reference Newtonian mechanics works fine in non-inertial frames if you include fictious forces; if properly generalized, it is actually more general than Lagrangian mechanics as it does not require forces to be derived from a potential
Jan
15
answered What is potential energy truly?
Jan
15
comment Where is the potential energy saved?
@Sofia: you'd have to ask Worldsheep about why he felt the need to qualify these statements; possibly, it has to do the GR (no energy density for gravity) and the non-uniqueness of the Poynting vector, but he may have been thinking about something completely different...
Jan
15
comment Where is the potential energy saved?
@Sofia: yes, we're in agreement; I just did not get your objection until your final comment
Jan
15
comment Where is the potential energy saved?
@Sofia: from your answer one understands that the electric field and the potential are due only to the bigger charge no, one has to consider the field generated by both charges; the potential energy comes from the mixed term when evaluating $|E_1+E_2|^2$
Jan
15
comment What is potential energy truly?
yes, I was getting at the $00$ component of stress-energy; also note that Noether's 2nd theorem does apply to GR...
Jan
15
comment What is potential energy truly?
note that we need to answer the 'where' question for anything besides gravitational energy if we want to apply general relativity...
Jan
15
comment Where is the potential energy saved?
@Sofia: and the energy density of the electromagnetic field will have increased by the required amount; take 2 charge configurations A and B, integrate the difference of electromagnetic field energy density and you'll arrive at the potential energy
Jan
15
comment What is potential energy truly?
One does not need to imagine energy as being stored somewhere. Yeah, it isn't as if the energy density appears anywhere important - like, say, the RHS of the Einstein equations? :p
Jan
14
comment Where is the potential energy saved?
@Sofia: I do not understand your objection; as long as you only bring an arbitrary but finite amount of charges, the potential energy will be finite; anyway, if I recall correctly, the interpretation of potential energy as field energy (once you substract the self-energy of the charge) can be found in chapter 1 of Jackson's EM book