Index notation of matrix tranpose

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The discussion focuses on the definition of matrix transpose in the context of index notation, specifically referencing Zee's work in "Einstein Gravity in a Nutshell." It clarifies that the transpose is defined without exchanging indices, which some participants initially interpreted as a typo. The importance of the left-to-right order of indices is emphasized, as it determines row and column positions in matrix representation. Additionally, the significance of slightly shifted indices is questioned, highlighting the complexity of index notation in tensor calculus. Understanding these nuances is crucial for grasping the mathematical framework of general relativity.
birulami
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Zee writes in Einstein Gravity in a nutshell page 186

"let us define the transpose by ##(\Lambda^T)_\sigma^\mu = \Lambda_\sigma^\mu##"

and even emphasizes the position of the indexes. Yes, they are not exchanged! This must be a typo, right?
 
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No, what he says is perfectly fine: he writes ##\Lambda^{\mu}{}{}_{\sigma} = (\Lambda^T)_{\sigma}{}{}^{\mu}## which is not what you wrote above.
 
And you are telling me now that this glitch in the typography of the slightly out of place indexes is the crucial point?:cry:

Oh my, I thought I understood why we have upper and lower indexes? But what is the meaning of an index slighly shifted to the right?
 
birulami said:
And you are telling me now that this glitch in the typography of the slightly out of place indexes is the crucial point?:cry:

Oh my, I thought I understood why we have upper and lower indexes? But what is the meaning of an index slighly shifted to the right?

The left-to-right order of the indices matters: in a matrix representation the first index is the row index and the second index is the column index.

A_\lambda{}^\mu = g_{\lambda\nu} \, A^{\nu\mu} = g_{\lambda\nu} \, g^{\mu\sigma} \, A^\nu{}_\sigma
 
MOVING CLOCKS In this section, we show that clocks moving at high speeds run slowly. We construct a clock, called a light clock, using a stick of proper lenght ##L_0##, and two mirrors. The two mirrors face each other, and a pulse of light bounces back and forth betweem them. Each time the light pulse strikes one of the mirrors, say the lower mirror, the clock is said to tick. Between successive ticks the light pulse travels a distance ##2L_0## in the proper reference of frame of the clock...

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