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1d
revised Diagonal part of the configuration space of two indistinguishable quantum particles
edited body
1d
answered Diagonal part of the configuration space of two indistinguishable quantum particles
Jul
7
answered Can the Berry Connection be derived from a metric?
Jul
3
awarded  Good Answer
Jun
27
revised Generalization of De Rham cohomology for spinor fields
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Jun
27
answered Generalization of De Rham cohomology for spinor fields
Jun
3
answered Geometric measure of entanglement in example with GHZ state
May
21
comment If a symmetry operator S in a QFT annihilates the vacuum, why does S preserve the space of 1-particle states?
@Void 2) Assuming Lorentz symmetry, the renormalization factors Z in ψ R =Z(ψ)ψ are Lorentz scalars, thus nothing essential changes in the analysis when the true renormalized field is used: Its transformation properties remain the same.
May
21
comment If a symmetry operator S in a QFT annihilates the vacuum, why does S preserve the space of 1-particle states?
@Void 1) Please think for a moment of $Q$ as the electric charge operator, you can write it uzing the Gauss' law as a surface integral of the electric field over a very large sphere at infinity. Due to the large distance these fields do not produce singularities when multiplied by other fields, thus the only singualrities coming from the commutator are those due to the local field $\psi$, thus the commutator itself is also a local field at $x$.
May
14
revised If a symmetry operator S in a QFT annihilates the vacuum, why does S preserve the space of 1-particle states?
added 12 characters in body
May
14
answered If a symmetry operator S in a QFT annihilates the vacuum, why does S preserve the space of 1-particle states?
May
5
comment The $U(1)$ charge of a representation
@JakobH The generator of the U(1) charge $Y_{\gamma}$ needs by definition to commute with all root generators $E_{\gamma}$ of the unremoved nodes. The Cartan-Weyl generator $H_i$ corresponding to the removed node does not possess this property, but its dual (called a coweight) does. The duality transformation can be accomplished on weight space by means of the metric tensor.
May
5
awarded  Nice Answer
Mar
11
awarded  Revival
Mar
6
awarded  Enlightened
Mar
6
awarded  Nice Answer
Mar
6
revised The Aharonov-Bohm effect is purely classical, right?
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Mar
5
comment The Aharonov-Bohm effect is purely classical, right?
@levitopher you can obtain the semiclassical aproximation (including the A-B effect) from the path integral, but Tuyman's theory requires even less structure than needed for the path integral. He does not require the symplectic form to be integral, thus does not impose the Dirac's quantization condition.
Mar
4
answered The Aharonov-Bohm effect is purely classical, right?
Feb
26
awarded  Good Question