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1 vote
1 answer
312 views

Anti-commutator of angular momentum operators for arbitrary spin

I know the commutator of angular momentum operators are $$ [J_i,J_j]=\mathrm i\hbar \varepsilon_{ijk}J_k. $$ For spin-1/2 particles, $J_i=\frac\hbar2\sigma_i$ where $\sigma_i$ are Pauli matrices, and ...
Luessiaw's user avatar
  • 695
2 votes
1 answer
207 views

Are there any 3 or more Hermitian solutions to the problem: $\alpha_i^2=1$, $\{\alpha_i, \alpha_j \}=2$

I’m trying to generate some matrices which are similar to Pauli’s but with the following anti-commutation relation $$\{\alpha_i, \alpha_j\}=\alpha_i \alpha_j + \alpha_j \alpha_i = 2 \tag{1}$$ And $$\...
J. Manuel's user avatar
  • 2,241
2 votes
1 answer
3k views

Anticommutator of spin-1 matrices

We know that in the spin-1/2 representation the anticommutation relation of the Pauli matrices is $\{\sigma_{a},\sigma_{b}\}=2\delta_{ab}I$. Does a similar relation hold for the spin-1 representation?
Antonis Kyriazis's user avatar
0 votes
1 answer
203 views

Anticommutativity of an anticommutator of supercharges

In this paper, equation 38 gives the ${\cal N}=2$ Super-Poincare (extended with the central extension $\mathcal{Z}$). The anticommutation relation of the two different supercharges is given as: $$\{Q^...
user45757's user avatar
  • 199
6 votes
3 answers
4k views

Is there an anticommutator relation for orbital angular momentum?

So I know that there are commutator relations for $L$ such as $[L_x,L_y] = i\hbar L_z$, but is there a relation for the anticommutator? For example, $L_xL_y + L_yL_x$?
ConfusedStudent's user avatar
1 vote
2 answers
425 views

How to prove the translation generator commutes with the spinors in SUSY algebra?

I was reading Modern Supersymmetry by John Terning, the book starts with SUSY algebra and says $$ \left[ P_{\mu} , Q_{\alpha} \right] = \left[ P_{\mu} , Q_{\alpha}^{\dagger} \right] = 0 $$ I am ...
zyy's user avatar
  • 247
0 votes
0 answers
215 views

Anti-commutator version of Zassenhaus formula

The Zassenhaus formula goes like $$ e^{t(X+Y)}= e^{tX}~ e^{tY} ~e^{-\frac{t^2}{2} [X,Y]} ~ e^{\frac{t^3}{6}(2[Y,[X,Y]]+ [X,[X,Y]] )} ~ e^{\frac{-t^4}{24}([[[X,Y],X],X] + 3[[[X,Y],X],Y] + 3[[[X,Y],Y],...
ann marie cœur's user avatar
15 votes
3 answers
6k views

The anticommutator of $SU(N)$ generators

For the Hermitian and traceless generators $T^A$ of the fundamental representation of the $SU(N)$ algebra the anticommutator can be written as $$ \{T^A,T^{B}\} = \frac{1}{d}\delta^{AB}\cdot1\!\!1_{d} +...
AltLHC's user avatar
  • 609