From: John Jones on
glird wrote:
>
> This topic really should be discussed on the relativity group. -
> fd
>
> Your message has been rejected because it is off topic of the
> moderated group sci.physics.foundations.
>
> On Mar 20, 3:19 am, Tom Roberts wrote:
> > glird wrote:
> >
> > > As of now, no gravitational waves have ever been detected.
> > > Why, then, are most physicists sure they exist?
> >
> > This is not true. Hulse and Taylor received a Nobel Prize for the
> detection of the emission of gravitational waves by a distant binary
> pulsar. That is an indirect detection, and lends plausibility to their
> existence, and implies that GR is a good model of them. >
>
> Although "an indirect 'detection'" did lend "plausibility to the
> existence" of g-waves, my statement holds good.
>
> TR: We aren't "sure" they exist, we just think it is quite likely
> and
> merits the effort [= $$$$$] required to detect them directly.
>
> If, as you implied, the emission of gravitational waves has been
> detected, then why aren't our physicists sure they exist?
>
> g: < As Lorentz pointed out, because the arms of an interferometer
> shrink by Q, q, q in the X, Y, Z directions -- where Q = q^2 = c^2 -
> v^2 and X is the direction of motion, a beam of light will take the
> same amount of time to round-trip the arms even though the arms are
> different lengths than each other AND the speed of light is similarly
> different relative to each such leg.
> Tom Roberts will disagree, of course. He believes that the length
> contractions don't physically happen, but are due to rotations of
> the X axis of a moving system, as Minkowski assumed. >
>
> TR: It's not just me, it's everybody who understand SR. That
> includes tens of thousands of physicists.
>
> If you were right, then (as proved below) that EXcludes Albert
> Einstein!
>
> g: Even so, we have a right to assume that the axes of any moving
> system are and remain parallel to each other.
>
> TR: No, you have no such "right" -- you must follow the structure of
> the model.
>
> You can follow Minkowski's model, but I will follow E's SR model.
> E wrote,
> "Now to the origin of one of the two systems (k) let a constant
> velocity v be imparted in the direction of the increasing x of the
> other stationary system (K), and let this velocity be communicated
> to the axes of the co-ordinates, the relevant measuring-rod, and
> the clocks. To any time of the stationary system K there then will
> correspond a definite position of the axes of the moving system,
> and ... we are entitled to assume that the motion of k may be such
> that the axes of the moving system are [and remain] ... parallel to
> the axes of the stationary system."
>
> TR: In SR, the rotation is in a space-time plane -- in 3-space they
> remain parallel (for the usual simple situation of a moving ruler
> aligned along the x and x' axes moving inertially along those same
> axes).>
>
> In fantasy land there might be an xyz;t plane. In reality, a plane
> is an imaginary mathematical construction with TWO dimensions, not
> three or four. In normal space, as in Einstein's world -- in which
> time was NOT a dimension -- all three spatial axes are and remain
> parallel despite Minkowski's mythical delusions.
>
> glird