Re: [Phys-l] two kinds of electrical charge ????????

[John Denker <jsd@av8n.com>]

On 07/31/2007 12:58 AM, James McLean wrote:
> Hmm, if there is only one type of charge, how many types of mass are 
> there?  One-half of a type?
>
> (Not even sure if that rises above the level of a joke. :-)

If I may be allowed to make a mockery of a joke:

Charge can be represented on the number line:
  http://www.av8n.com/physics/one-kind-of-charge.htm#fig-number-line

The number line is one dimensional.

Mass can be represented on the non-negative half of the number line.

Are you trying to tell me that the half-line is half dimensional?
I hope not.

Conversely, if you agree that mass is a one-dimensional quantity,
are you trying to suggest in a backhanded way that charge is a 
two-dimensional quantity, such as would be represented on the 
coordinate plane (as opposed to the number line)?  I hope not.


The idea of having multiple kinds of a charge-like quantity is
not at all far-fetched;  it just doesn't apply to electrical 
charge.  As Dan Crowe pointed out (thanks!), there are three
kinds of color charge.  This has been known for 40 years.

The symmetry of the color charge is SU(3) while the symmetry
of plain old electrical charge is U(1).  That three and that
one allow us to say with considerable formality and precision
that there are three kinds of color charge and only one kind
of electrical charge.

I added this point to my web page:
  http://www.av8n.com/physics/one-kind-of-charge.htm#sec-color

See also references therein.


Any theory that depends on one variable can be dressed up to
make it look like it requires two (or more) variables, but it
would be pointless to do so.  It would be worse than useless.