I dont have access to textbooks. The internet at present is pretty much my only source of information. I tried looking on the net but couldn't find anything pertaining to my questions.(adsbygoogle = window.adsbygoogle || []).push({});

Ok so I have the expression for a Poincare invariant action. Then I have to find the variation of the action.

What does the variation of the action mean? What is the basic formula for it, i.e the formula for the action was dS = L dt. What is the basic formula for the variation of the action?

I tried looking on the net but couldn't find anything pertaining to my questions. I appreciate greatly what was given in my other thread on the same subject but I should have mentioned I was looking for the basics.

Thankyou very much.

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# Homework Help: What is a variation of the action?

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