“Spin Networks are defined by Baez as "...graphs embedded in a manifold S (the space of spacetime) with edges labeled by representations of a Lie group G and with vertices labeled by intertwining operators. Spin networks define gauge-invariant functions on the space A of connections of any G-bundle over S...".
at http://www.astronomy.net/forums/god/messages/31152.shtml Wandaqueen wrote:
"LQG has further soldidfied the real existence of space by proving that it is quantized and independent of coordinate system.
I responded at http://www.astronomy.net/forums/god/messages/31164.shtml
To demonstrate one thing, such as that space is independent of coordinate system and hence not measurable, one must have a measurement system which has failed and an explanation
That was a typo until you add the word in boldface.
Wandaqueen responded at http://www.astronomy.net/forums/god/messages/31165.shtml Space is of course measurable using any coordinate system you like. The point is that an assumption in both General Relativity and Loop Quantum Gravity is that spacetime does not depend on the particular coordinate system you use.
It seemed to me that “independent of coordinate system” was being discussed in terms of time dilation in relativity and various special cases. I did not realize you were basically just talking about the idea, as you mentioned, that different units do not affect the measurement. The latter is universally true, as far as I know. It would be unnecessary to make a special case of saying so in physics.