Products of gamma matrices in n dimensions

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SUMMARY

This discussion focuses on the identities of gamma matrices in n dimensions, specifically the properties of the totally antisymmetric products of gamma matrices, denoted as γ(n)μ1... μn. The key equations involve the Kronecker product, represented as γ(n)⊗γ(n), and the discussion outlines two main identities that must be proven. The identities relate to the anticommutation relations of gamma matrices and the n-dimensional identity matrix, with μ defined as d/2, where d is the dimension.

PREREQUISITES
  • Understanding of gamma matrices and their properties in quantum field theory.
  • Familiarity with the Kronecker product and its application in tensor algebra.
  • Knowledge of antisymmetric products and their definitions in the context of linear algebra.
  • Basic concepts of anticommutation relations in the context of fermionic fields.
NEXT STEPS
  • Study the properties of Kronecker products in linear algebra.
  • Learn about the antisymmetric product of matrices and its applications in physics.
  • Research induction methods for proving identities in higher-dimensional algebra.
  • Explore the implications of gamma matrices in quantum field theory, particularly in relation to spinors.
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Physicists, mathematicians, and students studying quantum field theory, particularly those focusing on the algebra of gamma matrices and their applications in theoretical physics.

Michi123
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Hello,

i have here some identities for gamma matrices in n dimensions to prove and don't know how to do this. My problem is that I am not very familiar with the ⊗ in the equations. I think it should be the Kronecker-product. If someone could give me a explanation of how to work with this stuff it would be great.
here the exercise:
Let γ(n)μ1... μn be the totally antisymmetric products of n γ-matrices and γ(n)⊗γ(n) = γ(n)μ1... μn ⊗ γ(n)μ1... μn.

it should hold that:
1.)γμ γν γ(2)⊗γμ γν γ(2) = γ(4)⊗γ(4) +2(5μ -4) γ(2)⊗γ(2) +4μ(2μ-1) id⊗id
2.)γργμγσγν⊗γργνγσγμ= -γ(4)⊗γ(4) +4γ(2)⊗γ(4) + 4μ(3μ-1) id⊗id

id is the n dimensional identity matrix and μ =d/2 where d is the dimension
for the gamma matrices in n dimensions also holds the basic anticommutation relation and ημνημν = d

greetz mk
 
Ok, I think the antisymmetric product of the gamma-matrices is defined by:
##\gamma^{(n)} =\gamma^{[\mu_1\mu_2\ldots\mu_n]}= \frac{1}{n!}\epsilon_{\mu_1 \mu_2 \ldots \mu_n}\gamma^{\mu_1}\gamma^{\mu_2}\ldots\gamma^{\mu_n}##
It would be good to show that ##\gamma^\nu\cdot\gamma^{[\mu_1\mu_2\ldots\mu_n]} = \gamma^{[\nu\mu_1\mu_2\ldots\mu_n]} + \sum\limits_{i=1} ^n (-1)^{i+1} g^{\nu\mu_i}\gamma^{[\mu_1\mu_2\ldots\hat\mu_i\ldots\mu_n]}. ##The ## \hat\mu_i## means that this indice is deleted from the product because ##\nu## and ##\mu_i## were equal. So if ##\nu## is different than all other indices, I'm left with a n+1 matrices product. If ##\nu## matches with one indice, I'm left with a n-1 matrices product. I am not pretty sure how to do this. For the cases n=2 or n=3 one can do this simply and just form an antisymmetric product to see how this works. But I can't do this for the general case, i.e. for arbitrary n. Perhaps one can do this by induction or just by using some combinatorial stuff?! If one has this identity, the tensor-product identities in the first post should follow by using this relation.
 
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