Quick question, index notation, alternating tensor.

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binbagsss
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Q) I am using index notation to show that ε[itex]^{0123}[/itex]=-1 given that ε[itex]_{0123}[/itex]=1.

The soluton is:

ε[itex]^{0123}[/itex]=g[itex]^{00}[/itex]g[itex]^{11}[/itex]g[itex]^{22}[/itex]g[itex]^{33}[/itex]ε[itex]_{0123}[/itex]=-ε[itex]_{0123}[/itex]

where g[itex]_{\alpha\beta}[/itex] is the metric tensor.

I am struggling to understand the last equality.

Many thanks for any assistance.
 
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binbagsss said:
Q) I am using index notation to show that ε[itex]^{0123}[/itex]=-1 given that ε[itex]_{0123}[/itex]=1.

The soluton is:

ε[itex]^{0123}[/itex]=g[itex]^{00}[/itex]g[itex]^{11}[/itex]g[itex]^{22}[/itex]g[itex]^{33}[/itex]ε[itex]_{0123}[/itex]=-ε[itex]_{0123}[/itex]

where g[itex]_{\alpha\beta}[/itex] is the metric tensor.

I am struggling to understand the last equality.

Many thanks for any assistance.

Look up the definition of the metric tensor you are using and insert the values of the g components.