[vsnet-campaign-nova 948] Re: V2540 Oph - detection of period/s

[Alon Retter <retter@Physics.usyd.edu.au>]

Dear Taichi,

Thank you for your email. I do not underestimate Nir Shaviv's work.
However, one should remember that theoreticians are not always right.
Shall I give you a few examples? A nice paper by someone (no names) in
1983 explained very nicely why novae can't be magnetic. After the
detection of the first magnetic nova (V1500 Cyg in 1987) he wrote quickly
a paper that explains why it is possible. I was very lucky found in my
Ph.D. thesis evidence for the early presence of the accretion disc in a
few cases. This was inconsistent with the common belief of theoreticians
that it takes only a few decades for the disc to reform. Recently, after a
discussion with Dr. Iben in Sitges I found out that his models allow the
presence of a helium AM CVn-like nova. You surely remember how several
theoreticians strongly attacked this idea I presented in the Kyoto
conference a few years ago. 

Yes, Nir Shaviv has a nice model with physical parameters. Yes, he can
mimic the light curve of novae. No! The problem hasn't been solved yet!

I'm sure you know that DQ Her, GK Per are well established intermediate
polars novae. It was also suggested that V603 Aql is an intermediate
polar although there is still a debate on its nature. LM Mus (1998), a
nova that has shown the transition phase was classified by us as an
intermediate polar since several periods were detected in its light 
curve. 4 years after outburst it is very bright in the X-rays despite of
its large distance, which is consistent with this suggestion.

I proposed the connection between intermediate polars and novae 4 years
ago, since then 3 or 4 objects seem to obey the connection. A simple
calculation shows that it is thus very significant. Is it a coincidence
that V1494 Aql (transition phase) has a short X-ray period? Is it just
chance that V382 Vel (no transition phase) doesn't have a short X-ray
period? Is it just luck that V1039 Cen (transition phase) has many
photometric periods? And now V2540 Oph (transition phase) also seems to 
be an intermediate polar. Assuming that 20% of CVs are intermediate
polars, my prediction is 97% (3 cases) or 99.4 (4) significant. A physical
theory is defined as such that can be confirmed or refuted. My model was
attacked and still survives. It is thus a good model unless proven else.
It is very easy to `solve' problems but it is more difficult to give
predictions.

Even if I don't have a consistent model yet it does not mean that I'm
wrong about this idea. Sorry I won't reconsider my idea unless the
observations show that I'm completely wrong.

The main idea of my model is that the accretion disc is destroyed by the
nova outburst only in intermediate polars. This is since it is less
massive and it is easier for the outburst to destroy it as it is truncated
at the inner part. If you want to learn more on my idea, I'll send you a
copy of my contribution to the Sitges proceedings.

Best wishes,
Alon
-----------------------------------------------------------------------
   Dr. Alon Retter          Tel. (work)     +61-2-9351-4058
   School of Physics        Fax  (work)     +61-2-9351-7726
   University of Sydney     -------------------------------------------
   Sydney, 2006             'As a scientist I don't believe myself, so
   Australia                why should I believe you?' (A.R. 1965-2085)
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