From: metares@well.sf.ca.us (Tom Van Flandern)
Subject: Re: Detecting Second-Order GR Effects in Binary Pulsars
Organization: Whole Earth 'Lectronic Link
Date: Wed, 16 Dec 1992 16:39:23 GMT


matt@physics2.berkeley.edu (Matt Austern) writes:

> The claim, then, is that gravitational radiation is *not* a solution to the
> vacuum form of the Einstein field equations?
>
> Frankly, I find that claim very difficult to accept.  The vacuum Einstein
> equations just aren't all that complicated, and I don't see any way that
> you could fail to get waves from them.  Can you provide some more details?

     Okay, Matt, here's a quick summary of Yu's argument.  [Please remember
my caveat that important arguments are best read in their original form,
since summaries can inadvertently omit important details.]  Yu first traces
the development of the gravitational radiation formula from Einstein,
Lorentz, and Levi-Civita through the modern work by Ehlers, Damour, Walker,
Schutz, and Will.  He comments that several versions of the quadrupole
formula have been derived with different interpretations and varying degrees
of consistency by these authors.

     Yu then cites the earlier, similar conclusions of Denisov and Logunov
(1983), who argue that GR does not and cannot have energy momentum
conservation laws when a gravitational field and matter are taken in
conjunction; and that the inertial mass defined in GR has no physical
meaning.  Although Yu does not cite him, Yilmaz has made similar points in
arguing for his own "completion" of GR.  But Yu admits these arguments are
controversial, so he adopts a different approach.

     Next, Yu derives the quadrupole radiation formula (-dE/dt = ...),
emphasizing its one-body nature.  Then he says, "However, for a finite
neutral particle system, the theory proves illusory ...," and he proceeds to
show that the right-hand side in that equation must reduce to zero for such a
system.  Quoting again, "That is, there is no energy transported due to
gravitational radiation; or, shall we say, the Einstein approximation scheme
gives no gravitational radiation.  The argument goes with any particle system
by induction.  ...  The claim that observed data from PSR 1913+16 has
verified Einstein's gravitational radiation theory is, therefore,
groundless."

     I think this is based on reasoning similar to the argument others have
made that the Schwarzschild solution is a one-body solution; and that when
extended to two or more bodies, the field equations are no longer satisfied.

     I'm not fluent in TeX yet, so feel handicapped when it comes to posting
the half-a-dozen relevant equations, replete as they are with Greek letters,
super- and sub-scripts, d'Alembartians, and the usual fun GR operators.  But
the whole paper is 4.5 pages, and the meat of it is on half a page.  So those
familiar with GR notations will find it easy reading.

     These are important issues.  I sure wish the field and its experts could
address these new challenges in a clear, comprehensible way, and without once
saying "but Einstein couldn't have been wrong about this."  -|Tom|-

-- 
Tom Van Flandern / Washington, DC / metares@well.sf.ca.us
Meta Research was founded to foster research into ideas not otherwise
supported because they conflict with mainstream theories in Astronomy.
Xref: sparky sci.astro:13083 sci.space:17515