Re: Time Dilation disappears

On Sat, 6 Dec 2008 00:16:52 -0800 (PST), Jerry <Cephalobus_alienus@xxxxxxxxxxx>
wrote:

On Dec 4, 4:49 pm, hw@..(Dr. Henri Wilson) wrote:
On Wed, 3 Dec 2008 18:54:20 -0800 (PST), Jerry <Cephalobus_alie...@xxxxxxxxxxx>
wrote:
On Dec 3, 3:29 pm, hw@..(Dr. Henri Wilson) wrote:


How do YOU explain the changes in DV Uma curve between 2005 and 2007?
http://www.britastro.org/vss/(ccd light curves)

DV Uma is a cataclysmic eclipsing binary at high inclination,
which results in deep eclipses. One of the binary components is
a dwarf nova that is stealing mass from the other. This mass
transfer results in a large accretion disk that contributes
significantly to the light curve, resulting in its complex shape.
The accretion disk undergoes precession, so superimposed on the
basic shape of the light curve is a periodic "superhump". The
light curve appears quite different at different times depending
on the precession angle of the accretion disk. Every few years,
enough mass accretes onto the dwarf nova that it flares up. After
a flare-up, the accretion disk is, for a while, highly distorted
from its usual flat circular shape, so the light curve is
variable for several cycles until it settles down to a more
normal shape.

This is typical of the confusion caused by Einstein.

Both these curves can be constucted using BaTh.
Uma 2005 is typical of a binary pair in orbit with e= 0.4 and yaw angle -55.
One star is moving at about 1/3 the speed of the other and has a brightness
maybe 2/3 that of the other.

The 2007 curve suggests both stars are following each other around the same
elliptical orbit 180 apart. Another object in fairly circular orbit is also
present. I would say a third cool object is now orbiting the binary pair.

You suggest that something catastrophic happened to this system
between 2005 and 2007. The orbits of the binary components, you
claim, were drastically rearranged by the introduction of a third
cool object to the system.

Yet my measurement of the period of the 2005 curve is 0.0860 days,
while my measurement of the 2007 curve gives 0.0859 days, which
matches my first measurement to within a single pixel on the
computer screen.

Your suggestion is hence totally unreasonable. Such a drastic
rearrangement of the system should not have left the orbital
period unchanged.

There is VASTLY MORE DATA available on DV Uma than the limited
luminosity curves available on the britastro site. DV Uma is of
great interest to astronomers because, as a dwarf nova, it has
shown repeated outbursts (every couple of years or so) since its
discovery in 1995, and as an eclipsing binary, the components of
this dwarf nova are much better characterized than were they not
eclipsing.

Approximately 1600 cataclysmic variable systems are known, of
which dwarf novae constitute a major subset. Cataclysmic
variable systems consist of a white dwarf primary plus a mass
transferring secondary, called the donor star.
http://imagine.gsfc.nasa.gov/docs/science/know_l2/cataclysmic_variables.html
http://en.wikipedia.org/wiki/Cataclysmic_variable_star
http://physci.llnl.gov/Research/CataclysmicVariables/

A handful of these cataclysmic variable systems have orbital
planes aligned in such a way that they are eclipsing systems.

OK I've had a closer look at D Uma.

It is indeed an eclipsing cepheid.
But the interesting thing is the eclipsing body of 2005 was possibly not the
same one as in 2007 although the similar periods suggest similar orbit
parameters. Assuming the main orbit is stable, the eclipses occurs at two
different orbit phases.

see: http://www.users.bigpond.com/hewn/uma.jpg

I can think of several possible ways that this might happen.

The green curve is a rough BaTh matching. e = 0.09, yaw angle about -118.
The irregularities in the top one are presumably due to brightness changes in
the companion stars, each of which is about 1/5th of the mass of UMA and
contributes only about 20% of the total brightness.

The observed 'superhumps' mentioned elsewhere are probably caused by Uma
wobbling around its barycentre with a very closely orbiting planet.
The main eclipsing object(s) is further away.

Jerry



Henri Wilson. ASTC,BSc,DSc(T)

www.users.bigpond.com/hewn/index.htm.

......
.

Relevant Pages

  • Re: Time Dilation disappears
    ... DV Uma is a cataclysmic eclipsing binary at high inclination, ... significantly to the light curve, ... Uma 2005 is typical of a binary pair in orbit with e= 0.4 and yaw angle -55. ...
    (sci.physics.relativity)
  • Re: Solving f(t) + C*cos(g(t)) for t
    ... > fis the position of the center of mass ... you could invoke the Inverse Function Theorem: ... a description of a curve in the plane. ... which you could now interpret as the graph of some function t = G. ...
    (sci.math)
  • Re: Howlers
    ... you could do dimensional analysis treating mass and time as ... Like a radius of curvature (of a curve at a ... Short and straight, it is.) ...
    (rec.arts.sf.composition)
  • Re: Time is No More (must invent new term for Time)
    ... curve in space time is a curve in time. ... Mass is just time coliding displacing or overlapping time with time. ... line from evry atom to the edge of the universe is shorter then he time ...
    (sci.physics)
  • Re: Gravity -- Fundamental Force or Space-Time Geometry?
    ... the presence of mass causes "space" itself to curve, so the moon is actually following a ...
    (sci.physics)