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## Main Question or Discussion Point

Barbour writes:

I please to write more visually and more precisely.

I suppose that the first four values are on diagonal?....

*the metric tensor g. Being symmetric (g_uv = g_vu) it has ten independent components,*

corresponding to the four values the indices u and v can each take: 0 (for the

time direction) and 1; 2; 3 for the three spatial directions. Of the ten components,

four merely reflect how the coordinate system has been chosen; only six

count. One of them determines the four-dimensional volume, or scale, of the

piece of spacetime, the others the angles between curves that meet in it. These

are angles between directions in space and also between the time direction and

a spatial direction.

corresponding to the four values the indices u and v can each take: 0 (for the

time direction) and 1; 2; 3 for the three spatial directions. Of the ten components,

four merely reflect how the coordinate system has been chosen; only six

count. One of them determines the four-dimensional volume, or scale, of the

piece of spacetime, the others the angles between curves that meet in it. These

are angles between directions in space and also between the time direction and

a spatial direction.

I please to write more visually and more precisely.

I suppose that the first four values are on diagonal?....