# Sign Convention in Field Theory

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?

• I recommend learning how to figure out which convention an equation is using. For example, a Lagrangian has a positive “kinetic” term. – G. Smith Oct 27 at 19:05
• Ok, could you recommend any exercise or resources from where to start? – Phrancesco Oct 27 at 19:11
• 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. – mike stone Oct 27 at 19:14

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