Is a (-,-,-,-) metric signature meaningful?

[jfy4]

Hi,

Is a metric signature of $(-,-,-,-)$ unphysical?

Thanks,

 

[bcrowell]

You can flip all four signs in the signature, and it doesn't mean anything in terms of connection with observation. For example, my favorite signature is +---, but much of the literature uses -+++. They don't mean anything physically different.

So ---- would be physically identical to ++++, describing Euclidean four-space. Such a space has no time dimension, just space.

 

[jfy4]

You can flip all four signs in the signature, and it doesn't mean anything in terms of connection with observation. For example, my favorite signature is +---, but much of the literature uses -+++. They don't mean anything physically different.

So ---- would be physically identical to ++++, describing Euclidean four-space. Such a space has no time dimension, just space.

Thank you very much.