| Fred,
|
[quoted text clipped - 5 lines]
| together with psi via a Dirac gamma, and it is this pairing that allows a
| tensor formulation.
Oops, maybe I phrased that poorly? Let me quote what he actually says
in chapter 31;
"Supergravity necessarily involves spinor as well as tensor fields, so
we will have to describe gravitational fields in terms of a vierbein (or
tetrad) e^a_u(x) rather than a metric,..."
So why would he be specifying spinor and tensor fields separately here?
Then in the Appendix for 31 he says;
"Unlike vectors and tensors, spinors have a Lorentz transformation rule
that has no natural generalization to arbitrary coordinate systems."
He does seem to be saying that spinors are different from vectors and
tensors. Well, it just seems obvious to me since spinors do have a
unique direction. So maybe it is not that baryons are a third rank
antisymmetric tensor but this tensor is representing something about the
baryon? Similar to how J^u is the current for a fermion?
FrediFizzx
| > | Hello again:
| > |
[quoted text clipped - 20 lines]
| >
| > http://www.vacuum-physics.com
Jay R. Yablon - 17 Oct 2005 20:44 GMT
So maybe it is not that baryons are a third rank
> antisymmetric tensor but this tensor is representing something about the
> baryon? Similar to how J^u is the current for a fermion?
Yes, Fred, I like better, your way of putting this.
Jay.
Ken S. Tucker - 20 Oct 2005 06:10 GMT
Hi Fred Jay and all
> | Fred,
> |
[quoted text clipped - 30 lines]
> antisymmetric tensor but this tensor is representing something about the
> baryon? Similar to how J^u is the current for a fermion?
Weinberg in Grav&Cosmo pg 58, 1st paragraph, discusses
introducing spinors, in the Lorentz transform to account
for "1/2 integer spin" denoted by omega in 2.12.5, and
is anti-symmetric.
Later on pg 365, "The Tetrad Formalism" he shows how
"spinors" can be incorporated into GR.
For interest see pg 367 where he mentions "dual
classification".
((IMHO I'm uncomfortable with spinors together with
a continuum, look at his 2.12.5 again and see the
condition,
|omega^a_b| << 1
that's a bit of a "shoe horn"))
Anyway he's trying to lay the ground work for
relativistic quantum field theory.
> FrediFizzx
Regards
Ken S. Tucker