Questions tagged [quantum-anomalies]
This tag is for anomalies in a symmetry, either in classical or quantum theories. DO NOT USE THIS TAG for anomalies in a measurement.
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Why M-theory has eleven dimensions? [duplicate]
Why M-theory has exactly 10+1 dimensions?
Some combinatorics with tensor indices will do.
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Chiral anomaly of Weyl fermion is half of Dirac
How can one mathematically see that the anomaly for a Weyl fermion is half of Dirac in the Fujikawa path integral method?
Edit
I do understand that a Dirac fermion is two Weyl fermions. What I wish to ...
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Local scale invariance without conformal anomaly
I need to know if conformal symmetry can be localized in the same manner that global symmetries like $SU(2)$ is localized and gauge bosons pop up?(I assume the trace anomaly doesn't violate the scale ...
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$U(1)^{3} $ anomaly, trace of a hypercharge?
I have recently found the definition of the $U(1)^{3}$ anomaly as:
$$\mathcal{A} = Tr[Y^{3}]_{L} -Tr[Y^{3}]_{R} $$
Where $Y$ is the hypercharge of the left, $L$ or right, $R$ components. What I don't ...
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Critical dimension from the symmetries of the string action
(Related: This post and this post.)
In this thesis it is said (on page 13) that just by assuming that we have some general action with the same symmetries as the Polyakov action (Poincare invariance, ...
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B violation and electric charge
Within SM you can prove that despite we have baryon number conservation respect to Noether theorem, at quantum level baryon (and lepton) number is violated as
$$
\Delta B = 3·\Delta n_{CS}, \quad n_{...
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Peskin equation on the treatment of chiral anomaly
In page 666 (it couldn't be other way - bad joke), chapter 19, the Eq. (19.73) claims (see properties of the $\phi_n(x)$ functions in this post: Change of variables in path integral measure):
$$
\...
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QCD Trace Anomaly and Mass
In the paper in equations 4 and 5, some of the mass of the nucleons comes from the "trace anomaly" of the QCD energy-momentum tensor (as described in the paragraph following these equations). Is there ...
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A Universe with only a single fermion
Is a Universe with only a single fermion anomalous instead of free from anomalies?
(e.g. electron, defined through fermi statistics with exchange statistics with a gained $-1$ sign, or rotating 360 ...
user32229
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290
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From gauge anomaly to chiral anomaly
Suppose the theory of chiral Weyl fermion (say, left) $\psi_{L}$, which interacts with abelian gauge field. This theory contains gauge anomaly, which I write in the form
$$
\frac{dQ_{L}}{dt} = \text{A}...
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Anomalous commutators and gauge anomaly
Suppose we know, that the dynamics of theory with chiral fermions (say, left) and gauge field (for simplicity, abelian) leads us to presence of anomalous commutator of canonical momentum $\mathbf E(\...
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The scale anomaly and dependence on scale
The scale anomaly states that if we have renormalizable theory without dimensionful function, which is scale invariant, then corresponding quantum theory may lost this symmetry because of ...
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Chiral anomaly and fermion number conservation
Chiral anomalies in QED and QCD violate fermion number conservation, since a U(1) vector symmetry corresponds to fermion number conservation. However, only the LH and RH fermion numbers are not ...
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Why does the violation of Ward identity not require cancellation of global anomalies?
This question is a continuation of the answer posted for this question about anomalies.
Is there a violation of the Ward identity associated with an anomalous global symmetry? If yes, why is the ...
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