anuttarasammyak's latest activity

I will summarize what I have written. The index-raising and -lowering relation for the metric tensor $$...

Ordinarily, ##~T^{\mu\nu}~## , ##~T_{\mu\nu}~## and ##~T^\mu{}_\nu~## are coordinate representation of the same coordinate-free object...

Thank you @JimWhoKnew for the clear and easy-to-understand explanation for the "anomaly". I have preffered to regard "new"...

Thanks. Even with this general caution, may we take it obvious that in tensor division of $$ \bar{g}_{\mu\nu} := g_{\mu\nu}+\delta...

In the world of metric tensor undertaking variation where the metric tensor is $$ \bar{g}_{\mu\nu} := g_{\mu\nu}+\delta g_{\mu\nu} $$...

@haushofer it is a good chance to learn from your comments. May I say that in GR when tensor ##A_{abc..}^{def...}## is written...

@haushofer Thanks for the teaching. $$ g_{\mu\nu}+\delta g_{\mu\nu} =( g_{\alpha\nu}+\delta g_{\alpha\nu}) (g_{\mu\beta}+\delta...

No, I don't know any case in tensors. That is one of the reasons that I think : I am afraid that you are against it in post #11...

@haushofer The equation is the application of the rule for raising and lowering the indices in use of the (varied) metric tensor to the...

Under variation of metric tensor, ##g_{\mu\nu}+\delta g_{\mu\nu} ## is a tensor but its parts ##g_{\mu\nu}## and ##\delta g_{\mu\nu} ##...

Why don't you start with the familiar case that all $$x^0,x^1,x^2,x^3$$ have dimension of length. All the metric tensor components, thus...

@anuttarasammyak Excellent! This was hugely helpful. I wish Dirac had been a little less cryptic. It's not often that one consults...

@anuttarasammyak Very helpful, thanks. I should have looked there, because Dirac's book takes a lot from LL. In my copy of LL, this...

@Kostic As for your question the explanation of L-L : seems a good complementary to Dirac.

I do not have academic background but I am involved in management of quantum computing research in a public institute. I observe most...