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6 votes
1 answer
154 views

Why is this transformation not regarded as a symmetry?

5 votes
4 answers
316 views

How can $U$ have an arbitrary zero point and still be extensive?

5 votes
3 answers
244 views

Hilbert transform in soliton paper

4 votes
3 answers
138 views

Notation/convention in thermo; How is $dE = TdS - PdV$ independent of $T$ and $P$?

3 votes
2 answers
435 views

Are Lie algebras of groups unique?

3 votes
2 answers
155 views

Does $S \ge 0$ follow from Callen's thermodynamic postulates?

2 votes
2 answers
95 views

Why is $d^2 U=0$ for a thermal reservoir?

2 votes
1 answer
144 views

Carroll's Spacetime and Geometry - Notion of open subset of a manifold

2 votes
1 answer
92 views

Details of using flat metric to raise/lower indices in linearized GR. I'm getting first order discrepancies

2 votes
1 answer
149 views

Killing tensor of Friedman-Robertson-Walker metric (not assuming flatness)

2 votes
1 answer
53 views

Extracting $\mathbf b$ from $M = a I + \mathbf b \cdot \mathbf S$, when $S_i$ are higher spin matrices?

2 votes
0 answers
75 views

Is my geometric interpretation of $T \left(\frac{\partial S}{\partial T}\right)_P = \left(\frac{\delta Q}{dT}\right)_P$ correct?

2 votes
1 answer
112 views

$\phi$ a pseudoscalar field $\Rightarrow$ $\phi(x^0, \vec 0) = 0$?

2 votes
1 answer
141 views

How can the position operator be displacement invariant?

2 votes
1 answer
479 views

Good alternatives to Georgi's Lie Algebras in Particle Physics? [duplicate]

1 vote
1 answer
62 views

$D(x)(I-P)\neq(I-P) \Rightarrow$ Not completely reducible?

1 vote
1 answer
66 views

Why am I getting this tensor rotation wrong?

1 vote
0 answers
38 views

Separation into $|\Psi_{CM}\rangle$ and $|\Psi_{R}\rangle$ in abstract representation?

1 vote
1 answer
153 views

A step in the derivation of the unitary time-evolution operator (time-ordered exponential)

1 vote
3 answers
265 views

Covariant gradient - What am I missing?

1 vote
1 answer
89 views

Is a Feynman vertex valid only if all its rotations are?

1 vote
1 answer
56 views

Is this the correct way to transform a trajectory between Galilean frames?

1 vote
2 answers
86 views

Differentiation of an operator equation in paper by Chen, Lee, Pereira 1979

1 vote
1 answer
62 views

Abuse of notation in GR? $f(x)$ vs. $(f \circ \psi^{-1})(x)$

1 vote
1 answer
65 views

How can $p$ linearly independent vector fields span $m$-dimensional tangent space when $p>m$?

1 vote
1 answer
50 views

How are these two expressions for the canonical partition function equivalent?

0 votes
1 answer
48 views

Derivation of dual vector component transformation. Wald's book

0 votes
1 answer
107 views

Does $\{\gamma^\mu,\gamma^\nu\}=2g^{\mu\nu}\mathbb1$ determine the hermiticity of the gamma matrices?

0 votes
2 answers
233 views

Since two dimensions is enough to faithfully represent $SU(2)$, how can there be irreducible representations of dimension $n>2$?

0 votes
1 answer
106 views

Confusion about group representation terminology in physics