robphy said:
Possibly interesting reading:
http://www.dwc.knaw.nl/DL/publications/PU00012213.pdf
P. Ehrenfest, In that way does it become manifest in the fundamental laws of physics that space has three dimensions?
KNAW, Proceedings, 20 I, 1918, Amsterdam, 1918, pp. 200-209
http://rsta.royalsocietypublishing.org/content/310/1512/337.short
J. D. Barrow, Dimensionality
Phil. Trans. R. Soc. Lond. A 1983 310 337-346; DOI: 10.1098/rsta.1983.0095.
http://www.physics.princeton.edu/~mcdonald/examples/2dem.pdf
and a very old thread
https://www.physicsforums.com/threads/why-is-space-time-3-1-dimensional.109090/
These articles are amazing. Thank's a lot.
1- In Barrow's article I noticed something (page 341, paragraph 2) . He is explaining that in even numbered dimensions signal reverberation will be happen (for light). And then he is explaining that this result may lead us to think that we live in a odd dimension world so that high fidelity information transmission at a neurological level can happen or etc. Then how we are living in a 4D world ?
If 3D refers to just a space dimension then why time dimension would be different then the space dimension in the content of relativity ?
2- Again in Barrows article, where Fundamental units are defined, what's the meaning of the Eqn. 20. I didnt understand that part. What he is introducing to the reader.
3- In your last article that you shared, I realized that even in 1+1 dimension we can have an electric charge and electric field related to it, quoting
"In 1 + 1 electrodynamics, with one spatial dimension, x, the field tensors (44) have components,
There is no magnetic field associated with moving electric charge, and no electric field due to moving magnetic charge. That is, the electric field is only due to electric charge, and the magnetic field is only due to magnetic charge."
Thats really amazing to define a charge in 1+1. Or in Barrows article the dimension of charge, changes relative to the length that's also interesting and I didnt quite understand it (like dimension is about length yes but is it changes about the properities of the charge ?)