# Palatini Formalism generalizes GR to include degenerate metric?

1. Apr 3, 2006

### kakarukeys

Some papers say that Palatini Formalism still works if the frame variables $$e^i_a$$
is not an isomorphism (from tangent bundle to frame bundle), this generalizes GR to include the cases of degenerate metric.

But one could not derive the Einstein's Equation if $$e^i_a$$ is not an isomorphism!!
Somebody please explain to me how it works?

2. Apr 3, 2006

### Blackforest

Can you please tell me (us) first what are these "some papers"? Then after having been reading them, I shall try to understand and to answer. Thanks

3. Apr 4, 2006

### kakarukeys

Okay.
For example,
http://arxiv.org/abs/gr-qc/9504036
page 26

and in Lectures on Non-perturbative Canonical Gravity, Abhay Ashtekar
he mentioned a generalization to degenerate metric case.

4. Apr 4, 2006

5. Apr 5, 2006

### kakarukeys

I read them and begin to understand.
But has anyone observed or proposed to observe spacetime of degenerate metric before?