From: mock@space.mit.edu (Patrick C. Mock)
Subject: Re: grav lensing
Originator: mock@benz
Reply-To: mock@space.mit.edu (Patrick C. Mock)
Organization: MIT Center for Space Research
Date: Sun, 30 Aug 1992 22:27:06 GMT


In article <BtrpAF.K1o@well.sf.ca.us>, metares@well.sf.ca.us (Tom Van Flandern) writes:

 ... long discussion of 0957+561 deleted.  Succinctly, we disagree.

> > Most of your objections have been due to your misunderstanding of the
> > standard model.
> 
>      Most of my objections come from the literature, are shared by others,
> and arise from an alternative model which appears to me to work even better
> than the standard model.  Couldn't I equally well say back to you, "Most of
> your objections have been due to your misunderstanding of the alternative
> model"?

I stand corrected.  Some of your objections in this particular thread have
been due to your misunderstanding of the standard physics of grav lenses.
I don't think the turnabout applies to me in this discussion because
I have been objecting to your misunderstandings of the standard theory.
I have not been attacking your alternate theories.  As I said
before I do not object to you presenting alternate models.

> 
> > I don't object to your presentation of alternate models.  I do object to
> > your claims that the standard model is wrong when it is clear that your
> > understanding of the standard model is so weak.  For example your claim
> > that gravitational lens are concave.  It took several careful posts by me
> > and others to explain one of the most basic properties of a gravitational
> > lens.
> >
> > I also object to your distortion of the scientific literature.  For example
> > in the discussion of chromatic effects above, you claimed the observations
> > of chromatic effects in a gravitational lens cast serious doubt on the
> > standard model.  Yet the paper you referred to gives a careful explanation
> > of why the chromatic effects can occur in gravitational lenses.  The
> > explanation relied on the standard theory and careful observations and you
> > completely ignored it.
> >
> > While I have enjoyed this discussion.  Your misunderstandings and
> > distortions cause me to be extremely skeptical of your work.  I do not make
> > these claims lightly.  You may claim that I've mislabeled the examples I
> > have given.  Nonetheless, I find these examples deeply troubling.
> 
>      One of the many unfair ways in which people in general, and politicians
> and lawyers in particular, discredit their opponents is to point to some
> error they have made, and argue that casts doubt on everything that person
> has said or done.  Your point is dangerously close to that sort of argument.

I did not mean to imply that these were the only instances.  I gave
specific examples to illustrate the types of "errors" I find troubling.
You most likely did not do these with specific intention.  Indeed I would
describe most of them as careless.  We all make mistakes but the two
things I complained about have occurred repeatedly.

The less serious claim for me is the issue of distortion.  I deliberately
used this strong word because that's how it appears to me.  In thinking
about it I now believe that most of the instances are due to careless
reading of the papers, but I still find the example I gave troubling.

The more serious claim is your misunderstandings and how you've handled
them.  I don't fault you for doubting the standard model or presenting
alternate theories.  What I find troubling from my perspective is your
attacks on a theory when your grasp of the basics of that theory is weak.

I think you must have a basic understanding of a theory before you can
properly attack it.  This is one reason I have not attacked your
alternate theories.  Yet in this case you repeatedly made claims about
the predictions of grav lensing theory that were just wrong.  When I
pointed out errors in your claims and good references for the standard
theory, you would come back with more incorrect claims.

The example I gave is particularly troubling to me because it shows that
your grasp of basic optics is also weak.  Your description of concave and
convex lenses was wrong.

> ... stuff deleted ...
>      You have pointed out two places where I was ignorant before, and am
> informed now, thanks to you.  But I do not think it is reasonable to
> generalize, even a little, that this lowers my overall credibility.  In fact
> I would counter-argue that people who adopt such a position are in large
> measure responsible for the high rate at which others will defend a wrong
> position long after the facts have made a practical defense untenable.  Part
> of credibility is admiting when one is wrong, and learning from one's
> mistakes.
> 
>      I have enjoyed our discussions because you are a knowledgable individual
> with a vast breadth of knowledge, some of which is in areas in which my own
> familiarity is weak.  I would respectfully suggest that I might know a thing
> or two about, say, dynamics (my original degree specialty) which you might be
> embarrassed to admit that you did not know.  But with such a vast and rapidly
> changing field, that would not lower my estimation of you one bit -- unless,
> of course, you gave a "Calvin's-father-type" explanation of, e.g., why the
> moon is a satellite of the earth despite the sun's gravitational force being
> twice as strong as the earth's, and then refused to part with it.  -|Tom|-

I am not skeptical because of your lack of specific knowledge.  I don't
doubt that there are important gaps in my knowledge.  I am skeptical
because your attacks on the standard theory have repeatedly included
claims about the standard theory that were not true.  These errors seem
to indicate to me that your grasp of the theory, which you are attacking,
is weak.  Therefore I do not I don't know where I can trust you and where
I can not.  However, skeptical does not mean that I will not listen to
you.  I encourage you in your endevours.  After all it may turn out that
we are all wrong.

Pat
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