Is This Invariant Calculation Correct?

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Homework Statement



Calculate the invariant
[tex] E^{\alpha \beta} E_{\alpha \beta}[/tex]



Homework Equations





The Attempt at a Solution


we apply the metric in this case,
[tex] E^{\alpha \beta} E_{\alpha \beta} = g_{\alpha n} g_{\beta m} E_{n m} E^{n m}[/tex]

is that even correct?
 
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Nusc said:
we apply the metric in this case,
[tex] E^{\alpha \beta} E_{\alpha \beta} = g_{\alpha n} g_{\beta m} E_{n m} E^{n m}[/tex]

is that even correct?

No, that equation is non-sensical...on the lefthandside [itex]\alpha[/itex] and [itex]\beta[/itex] are dummy indices (they are being summed over)...on the righthandside they are free indices and you also have [itex]m[/itex] and [itex]n[/itex] appearing 3 times (which is notational nonsense).


I assume you are given either [itex]E^{\alpha \beta}[/itex] or [itex]E_{\alpha \beta}[/itex]?