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Jul
17
revised Identify the coefficients of Operator Product Expansion (OPE)
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Jul
17
revised Identify the coefficients of Operator Product Expansion (OPE)
added 305 characters in body
Jul
17
answered Identify the coefficients of Operator Product Expansion (OPE)
Jul
17
comment BRST transformation of adjoint spinor
Since in second method you are treating $\eta$ and $\psi$ as operators so $(\eta\psi)^{\dagger}$ should be simply $\psi^{\dagger}\eta$ by usual matrix rules
Jul
7
comment Eigenstate of position+momentum?
@David You should post your answer. May be you can explain better.
Jul
7
comment Eigenstate of position+momentum?
All operators are constructed from position, momentum and spin operators by adding or multiplying them together. Addition/multiplication of operators shouldn't be confused with simple addition/multiplication of their eigenvalues. In particular position + momentum would be a completely different operator. Eigenfunctions of "position + momentum" are neither eigenfunctions of position nor of momentum; hence its eigenvalues can not be interpreted as simple sum of eigenvalues of position and momentum operators.
Jul
6
asked Why does tachyon arise in bosonic string theory?
Jul
5
comment Continuous phase transition only hold for infinite systems. Real systems are finite, hence, a paradox
Think of a function $f(L,g)$ which (as a function of $g$) is singular at some point $g=g_0$ in the limit $L\rightarrow \infty$. Then if you take $L$ to be some very large number (say $L=10^{23}$) you will see that the given function is already "almost singular" even though $L$ is not really infinite.
Jul
4
revised Question about Komar integral derivation in Wald
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Jul
4
suggested suggested edit on Question about Komar integral derivation in Wald
Jun
27
comment Why is $\{Q, P\} = 1$ for a canonical transformation?
This is definition of a canonical transformation. It is a transformation which preserves the form $dp\wedge dq$ of symplectic 2-form.
Jun
20
awarded  Yearling
Jun
19
comment why can't you use your cellphone on an airplane?
Nice question dear! +1
Jun
19
comment Commutator with a square root
@dimension10 Is it really that simple? I don't even understand how one would define the square root.
May
31
comment How does a sponge “suck” up water against gravity?
+1 this answer at least explains something and surely doesn't deserve downvotes.
May
31
comment Perfectly focusing refractive surface
It would be helpful if you can explain your question with a diagram.
May
26
comment Deriving the Angular Momentum Commutator Relations by using $\epsilon_{ijk}$ Identities
Forget about $\epsilon_{ijk}$. Try to derive $[L_1,L_2]=i\hbar L_3$ etc.
May
25
comment What goes wrong when one tries to quantize a scalar field with Fermi statistics?
Since you are using anticommutator for quantization so causality would require that the fields anticommute for all spacelike separated points. Since form of the field (as got from time evolution of eta's) will be same as in bosonic case so the fields will fail to anticommute for spacelike separated points. Hence time evolution of eta's is wrong since it is not in accordance with causality.
May
24
revised Is there a general systematic approach how to calculate the individual terms in an operator product expansion?
edited body
May
24
answered Is there a general systematic approach how to calculate the individual terms in an operator product expansion?