"sam ende" wrote in message
...
tadchem wrote:


There seems to be a common misconception that the 'dimensions'
mentioned in string theory (ST) and in QM are *geometric* dimensions.

yes, that is probably my misconception, from what i have read recently
though it seems that string theory is more a mathematical construct ?

Yes. Most theories in physics start with a more abstract mathematical
representation. For example, the Lorentz transformations predate Einstein's
Theory of Relativity.

Theories only become *explainable* when all the variables, operations, and
values can be correlated to quantities already known to physics or *defined*
for the purpose of use in the context of the theory.

For example, the 'dimensions' used to describe electron orbits in an
atom are the principle quantum number n, the angular momentum l (or j
if you prefer), the magnetic quantum number m, and the spin quantum
number s.

ST postulates that 10 orthogonal quantum variables are both necessary
and sufficient to specify a subatomic particle, be it a baryon, a
hadron, or a lepton, or anything else.

Hence the 'dimensions.'

okay, i don't really understand what you have written but i'll do some
reading, mainly it's the keywords you use, i don't know what they mean.
thank you.

This site links to many dictionaries, and gives some definitions based on a
'consensus' of the dictionaries:
http://www.onelook.com/?w=dimension&ls=a
If you examine the 'quick definitions' box on the right, you will see
several definitions for 'dimension.' The ordinary journalist-on-the-street
(IQ about 90) only knows the first definition:

noun: the magnitude of something in a particular direction (especially
length or width or height)

The typical mathematician (those who derive the equations on which physics'
theories are built) uses mainly the fourth definition:

noun: a construct whereby objects or individuals can be distinguished

Hence the confusion...

By the time he gets a Ph. D. the average physicist knows almost enough math
to have earned a B.S. in applied mathematics, so they are comfortable with
the terminology.


Tom Davidson
Richmond, VA