On May 12, 2010, at 7:42 AM, Mc wrote:


If we use the exponential metric there are no Black Holes, but the problem with an exponential metric is it doesn't solve Einstein's field equations so the metric gets truncated. 

The problem with that is we wind up with singularities, a physical impossibility from the standpoint of good Physics. 

So, what's wrong with Einstein's field equations that it can't accept an exponential metric which Einstein thought was correct?" Rmc

http://www.lns.cornell.edu/spr/2004-01/msg0057786.html

http://news.bbc.co.uk/2/hi/science_and_environment/10108226.stm

 


Black holes are an observational fact.

The metric representations are relative to timelike congruence of ideal observers formally defined by tetrad gravity fields.
You can write Puthoff's SSS exponential metric in the static LNIF set of observers and then ask what kind of matter stress-energy tensor Tuv would give that solution according to Einstein's field equation
Guv + (8piG/c^4)Tuv = 0
so far no observational evidence that it's useful.
Detailed studies of radiation from accretion disks etc by Martin Rees British Astronomer Royal, Master of Trinity College Cambridge, Head of the Royal Society and his Institute for Theoretical Astronomy have proved conclusively the factual status of black holes essentially described by the Kerr solution to a good approximation.

I think the facts make it very clear that there is no acceptable alternative to Einstein's GR that fits the astrophysical observations. That's my opinion for the record. All the evidence you need you can find here

& here
This is not to exclude torsion field effects in devices using superconductors along the lines of Ray Chiao. 
Torsion is a natural extension of Einstein's basic theory viewed as a local gauge theory on the global symmetries of his special relativity.
On May 12, 2010, at 8:57 PM, Paul Zielinski wrote:

On Wed, May 12, 2010 at 7:19 PM, JACK SARFATTI <This email address is being protected from spambots. You need JavaScript enabled to view it.> wrote:
WRONG! 
You can write any damn metric you like and then compute the energy tensor needed for that metric

"I think this is about an alternative set of field equations that is consistent with known observational data. It's not clear that Einstein's equations are the only ones that are mathematically admissible."
Who cares? All sorts of models are mathematically admissible, but are not useful for explaining and predicting real observations.

"It's not clear even in the context of Einstein's Riemannian model for gravity that Einstein's field equations  are the only ones that are consistent with observations."
The urls above clearly demonstrate that you are mistaken.
It's completely ignorant of real physics to say "Einstein was wrong" - that's really crackpot

"Einstein himself said that Einstein was wrong on fundamental issues Jack. For example, Einstein retreated from his early position that Poincare's ether was not a scientifically meaningful concept in physics. So I think  you are overplaying your hand here."
We have discussed this ad-nauseum you are, in my opinion, pulling Einstein's remarks out of context. Basically it's irrelevant what transient opinions the creators of their own theory may have had about their theories in the absence of relevant measurements and observations. Einstein died before the relevant technology had been developed to test his theory. The "ether" is a Red Herring. Depends what one means by "ether". Of course in quantum theory we have virtual particles inside the vacuum that is an "ether" that respects the local symmetries of GR in the appropriate limit. Sure you can think of the four spin 1 gravity tetrad Lorentz group vector fields e^I as fields on a locally flat Minkowski space where
ds^2 = (Minkowski)IJe^Ie^J = guv(accelerating local frame)e^ue^v
e^I(unaccelerating local frame) = (tetrad)^Iue^v(accelerating locally coincident frame)
In addition, the IT tetrads e^I are Bell pair spinor qubit entangled states in the quantum informational pre-geometry
e^I = (Newman-Penrose)^Iii'(Qubit)^i(Qubit')^i'
i.e.
IT FROM QUBIT

"How about black holes? Einstein said he didn't believe in them. You say that black holes are an observational  fact. Doesn't that make Einstein wrong, according to your own arguments?"
All irrelevant. If Einstein were alive today he would not dispute the reality of black holes.

On May 12, 2010, at 8:57 PM, Paul Zielinski wrote:


How about black holes? Einstein said he didn't believe in them. You say that black holes are an observational 
fact. Doesn't that make Einstein wrong, according to your own arguments?

All irrelevant. If Einstein were alive today he would not dispute the reality of black holes.

"The point here is if you are right about black holes, then you are basically saying that Einstein was wrong on a major  issue in gravitational theory, since as a matter of historical fact he rejected them as physical solutions to the 1916
field equations.. 

Does that make you a 'crackpot'? "

Einstein did not understand the full implications of the solutions of his field equations
no one did until Penrose & Hawking's global light cone techniques more than 5 years after Einstein died - assuming classical positive energy conditions violated in quantum theory of course. Paul your way of looking at theory is very bizarre in my opinion. You draw silly conclusions from innocuous historical accidents. 
What matters is
Guv + kTuv = 0
one can make singularity-free dark star solutions of them invoking dark energy / > 0 in the interior - so what?
From the outside it looks just like a black hole.
Your point is a quibble in my opinion.
On May 13, 2010, at 7:13 AM, Paul Murad wrote:

Jack:
 
"Sorry but I have to agree with Paul.  Your first comment was in response to an individual that indicated we need to keep an open mind and perhaps review what we know about the situation.
 
It was uncalled for that you would characterize him as a crackpot.  There is nothing wrong with saying we should go back and question the conventional wisdom because we may gain some new or unknown insights."
Paul M
Anyone who does not accept Einstein's theory of gravity as the only viable theory that fits observation in its proper domain of validity is ipso-facto a physics illiterate crank in my book. That's my opinion. I gave the reference from Cliff Will that supports my case. Alternative theories of gravity have the same status as the Nazi hollow Earth theory in my opinion.
Now this does not exclude the natural extensions of Einstein's 1916 GR e.g. adding "square root" tetrads, torsion, spinors etc - an experimental issue that does not contradict the basic principles of Einstein's theory, especially when viewed in terms of the deep principle of local gauge invariance.