Recent content by Bishal Banjara

  1. Bishal Banjara

    Classical Looking for book about relativistic classical field theory

    I believe the book "Gravitation: Foundations and Frontiers" by T. Padmanabhan (and his online lectures) is best. And Landau-Lifshitz's classical theory of fields, Feynman's lectures on Gravitation, Gravitation and Cosmology by S. Weinberg are better.
  2. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    Correction: This would lead to the expression of matter Lagrangian (not density) as
  3. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    I followed the reverse back derivation of $$T_{\mu\nu}$$ in the equation $$T_{\mu\nu}=\frac{2\delta(\sqrt{-g}\mathcal{L}_m)}{\sqrt{-g}\delta{g^{\mu\nu}}}$$ multiplying by $$\sqrt{-g}/2$$ and reintroducing the intergand. Further, we get variation of matter action as...
  4. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    That was my mistake that I apparently saw partial differentiation in my own post. It is even mistake at this time also, please make it as variation. I have no edit option.
  5. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    Yes, I am asking to retrieve the case. But if there is way to explore the variation of matter Lagrangian density with metric tensor resolving the variation, then don't this makes sense to solve the problem?
  6. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    I know the metric, then what is the mathematical relation between the Ricci scalar and stress energy tensor?
  7. Bishal Banjara

    I Obtaining the matter Lagrangian from the stress energy tensor

    Basically, the stress energy tensor is given by $$T_{uv}=-2\frac{\partial (L\sqrt{-g})}{\partial g^{uv}}\frac{1}{\sqrt{-g}}.$$ It makes easy to calculate stress energy tensor if the variation of Lagrangian with the metric tensor is known. But it is possible to retrieve matter Lagrangian if the...
  8. Bishal Banjara

    I Covariant Derivative Rank 2 Contravariant Tensor

    yes, @Orodruin had already mentioned. "If that is the best you can do at explaining what your "core quest" is, we might as well close this thread. Can you do any better?" but why?
  9. Bishal Banjara

    I Covariant Derivative Rank 2 Contravariant Tensor

    In the lecture of Leonardo Susskind, he writes the same form I mentioned when deriving the Christoffels from metric tensors. There are other also, Iets not make this as an issue but my core quest is other as I mentioned above.
  10. Bishal Banjara

    I Covariant Derivative Rank 2 Contravariant Tensor

    Particularly, lets take as as what you mentioned, $${\nabla}_{t}T^{tt}=\partial_{t}T^{tt}+\Gamma^t_{t\gamma}T^{t\gamma}+\Gamma^t_{r\gamma}T^{t\gamma}$$. Is this possible or not, if we extend the equation taking all summation where $$\gamma$$ runs from t to $$\phi$$ as...
  11. Bishal Banjara

    I Covariant Derivative Rank 2 Contravariant Tensor

    We could find numerous example following the covariant type as what I have done. My question is not exactly for that. I am expecting the difference in the result that I mentioned and what you mentioned (you could assume as what you took of contravariant type). I have mentioned the same way you...
  12. Bishal Banjara

    I Covariant Derivative Rank 2 Contravariant Tensor

    Why can't I write the covariant derivative of $$T_{tt}$$ components as $${\nabla}_{t}T_{tt}=\partial_{t}T_{tt}-\Gamma^t_{t\gamma}T_{t\gamma}-\Gamma^t_{r\gamma}T_{t\gamma}$$ where, $$\gamma$$ runs from $$t$$ to $$\phi$$?
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