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| bio | website | azimuthproject.org/azimuth/… |
|---|---|---|
| location | Munich, Germany | |
| age | 38 | |
| visits | member for | 2 years, 4 months |
| seen | May 28 '12 at 8:53 | |
| stats | profile views | 228 |
I'm a physics graduate working as an IT-developer and -consultant.
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Feb 2 |
answered | Shaking a jar of balls |
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Feb 2 |
comment |
How to explain the weak force to a layman? I don't know that many "laymen" who are familiar with the picture that EM forces come from the exchange of virtual photons :-) |
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Feb 2 |
comment |
How to explain the weak force to a layman? Is there a specific reason why the modern picture of the weak force is harder to explain than the other forces? |
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Feb 2 |
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How to calculate the volume of water from the measured rainfall? I have to a gree that this is not a question about physics, not even about meteorology in a broader sense, therefore I'm voting to close. |
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Feb 1 |
comment |
Formalization (and meaning) of Heisenberg Cut @Peter Morgan: The "state" in AQFT is an appropriate state of a net of operator algebras, it is not a state in the sense of pre-QM physics. The measurement process itself is not formalized in AQFT, AQFT stops with the statement "the expectation value of an observable x in a state y is...", which is a purely quantum concept. Of course the concepts of states and measurements did exist in pre-QM physics, but AQFT is not a "quantized" classical theory like e.g. Lagrangian QFT. There is no a priori given classical theory. |
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Feb 1 |
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Formalization (and meaning) of Heisenberg Cut @Roy: I'd draw the line and say that everything that phycisists calculate in QM with a formalized, mathematical framework does not have any connection to any concept like the Heisenberg cut. This concept is addressed, however, by people working on the philosophical interpretation of QM like Omnes. |
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Feb 1 |
answered | Formalization (and meaning) of Heisenberg Cut |
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Feb 1 |
comment |
Diff(M) as a gauge group and local observables in theories with gravity What about the event that a detector makes "ping" because it detects a particle (i.e. a sharply localized excitation of the appropriate quantum field)? Isn't this a local event that all observers will agree upon? |
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Feb 1 |
revised |
Diff(M) as a gauge group and local observables in theories with gravity added 661 characters in body |
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Feb 1 |
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Diff(M) as a gauge group and local observables in theories with gravity Sure, why not, I linked to the "Diff(M)" part because I agree with Streater on this one and did not want to repeat what he wrote. (I also happen to agree with him on the other points, but that's not important for the question at hand :-) |
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Feb 1 |
awarded | Student |
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Feb 1 |
comment |
Other possible theories (other than string theory) which are generalizations of the standard model with incorporation of gravity Your question is about a topic that has seen broad and sometimes violate discussions over the last 10 years, with tons of papers and hundreds of participants. Therefore I don't think that this question can be appropriatly handled on this site. |
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Feb 1 |
asked | Diff(M) as a gauge group and local observables in theories with gravity |
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Feb 1 |
comment |
Is the S-Matrix the only quantum field observable? @Peter: It's not a matter of being generous :-) Sorry, I don't understand "Everybody except Particle Physicists happily measure Wightman/correlation functions". Particle physicists use detectors, which are modeled in AQFT by almost localized observables, which is then an observable that is of interest and is not associated to the S-matrix (see the paper I mentioned). |
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Feb 1 |
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Is the S-Matrix the only quantum field observable? @Carl Brannan: Yes, but one can also define a charge operator in cases where there is no S-matrix |
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Jan 31 |
answered | Is the S-Matrix the only quantum field observable? |
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Jan 31 |
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Modes of a QFT and irreducible representation of the gauge group Maybe I'm missing something obvious but don't physical states in a gauge theory always have to be gauge invariant? |
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Jan 31 |
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Studying electrodynamics problems Is it to be understood that the students you have in mind are fluent with classical vector analysis and its integral theorems? (The classical versions of the general Stoke's theorem?) |
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Jan 31 |
awarded | Commentator |
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Jan 31 |
revised |
Does boundedness of observables in the Haag-Kastler axiomatization rule out interactions? added 530 characters in body |
