Integrals featuring the laplacian and a tensor

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SUMMARY

This discussion focuses on performing integrals involving the Laplacian operator and tensors, specifically in the context of functional differentiation. The integral presented is defined as \(\int\frac{\delta}{\delta A_{\mu}}\frac{1}{4M^{2}}(\partial_{\rho}A_{\sigma}-\partial_{\sigma}A_{\rho})\frac{\partial^{2}}{\partial x^{2}}(\partial^{\rho}A^{\sigma}-\partial^{\sigma}A^{\rho})\). It is established that the integration process is straightforward, but the functional differentiation of a term with triple space-time derivatives results in a value of zero. The key takeaway is that the expression simplifies to \(\frac{\delta F}{\delta A_{\mu}} \Box F\).

PREREQUISITES
  • Understanding of functional differentiation in the context of field theory
  • Familiarity with tensor calculus, particularly the properties of the tensor \(F_{\rho\sigma}\)
  • Knowledge of the Laplacian operator and its application in integrals
  • Basic concepts of space-time derivatives in theoretical physics
NEXT STEPS
  • Study the properties of the Laplacian operator in quantum field theory
  • Learn about functional differentiation techniques in advanced calculus
  • Explore tensor calculus applications in theoretical physics
  • Investigate the implications of zero results in functional differentiation
USEFUL FOR

This discussion is beneficial for theoretical physicists, mathematicians specializing in differential equations, and students studying advanced calculus or quantum field theory.

smallgirl
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Ok, so I'd like some advice on doing integrals that involve a laplacian and a tensor for example

[tex]=\int\frac{\delta}{\delta A_{\mu}}\frac{1}{4M^{2}}(\partial_{\rho}A_{\sigma}-\partial_{\sigma}A_{\rho})\frac{\partial^{2}}{\partial x^{2}}(\partial^{\rho}A^{\sigma}-\partial^{\sigma}A^{\rho})[/tex]

where [tex]F_{\rho\sigma}[/tex] is the tensor written out as [tex]\partial_{\rho}A_{\sigma}-\partial_{\sigma}A_{\rho}[/tex]
 
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The integration is not an issue. Actually you left out the integrating element. You must be having a functional differentiation of a 4-order derivative term shorthandedly written F box F. Since box F has triple space-time derivatives, it would yield completely 0 under functional differentiation. So you only have

[tex]\frac{\delta F}{\delta A_{\mu}} \Box F[/tex]
 

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