Why should the action be Lorentz invariant?

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Thread starter pellman
Start date Jul 31, 2009
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pellman

Thread starter
Jul 31, 2009

Why should the action be Lorentz invariant? Every time I come across this it is assumed by the author without qualification. As too obvious to explain maybe? Ain't obvious to me.

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AstroRoyale

Jul 31, 2009

https://www.physicsforums.com/showthread.php?t=193613

See also Greiner Chapter 2 of Field Quantization

pellman

Jul 31, 2009

i get it now. Thanks.

Why should the action be Lorentz invariant?

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Why should the action be Lorentz invariant?

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