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I am working with some field theory and I am at a point where I would like to change my sign convention from $(-+++)$ to $(+---)$. I am worried at some point I will just equations with the wrong sign because I am used to it and just going by memory.

Is there any table with the differences in sign for the "standard" equation (for example Lagrangians, energy-momentum tensor, equation of motion etc?

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    $\begingroup$ I recommend learning how to figure out which convention an equation is using. For example, a Lagrangian has a positive “kinetic” term. $\endgroup$ – G. Smith Oct 27 at 19:05
  • $\begingroup$ Ok, could you recommend any exercise or resources from where to start? $\endgroup$ – Phrancesco Oct 27 at 19:11
  • $\begingroup$ I wish there were such a table. I have notes for specific cases, but I still spend a lot of time getting the signs right. $\endgroup$ – mike stone Oct 27 at 19:14
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TL;DR: The main rule is that kinetic terms should be positive, cf. above comment by G. Smith.

Examples:

  • The Lagrangian density for a scalar field is $${\cal L}~=~\pm \frac{1}{2}\partial_{\mu}\phi\partial^{\mu}\phi -{\cal V}(\phi), $$ with EL equations $$ \mp\Box\phi~=~{\cal V}^{\prime}(\phi),$$ if the signature Minkowski metric is $(\pm,\mp,\mp,\mp)$, respectively.

  • Concerning the stress-energy-momentum (SEM) tensor, see this related Phys.SE post.

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Check Appendix E of Burgess & Moore's The Standard Model: A Primer. There is a pretty good collection of results like that there.

PS. Sorry to lose another soldier to the dark side that is the $(+---)$ metric (just kidding)

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