Re: The true crackpots


mluttgens@xxxxxxxxxx wrote:
> PD wrote:
> > mluttgens@xxxxxxxxxx wrote:
> > > PD wrote:
> > > > kenseto wrote:
> > > > > "PD" <TheDraperFamily@xxxxxxxxx> wrote in message
> > > > > news:1128178941.275246.204110@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> > > > > >
> > > > > > mluttgens@xxxxxxxxxx wrote:
> > > > > > > PD wrote:
> > > > > > >
> > > > > > > "... it is clear why the length of an object is *not* an
> > > > > > > inherent property of an object and it is much more easily grasped why
> > > > > > > this quantity is *of course* observer-dependent and, finally, why two
> > > > > > > observers can view each other's (identical) objects and each see them
> > > > > > > as shorter and that's not a problem. That is, it no longer is a
> > > > > > > "logical aberration".
> > > > > > >
> > > > > > > Yes, it is a logical aberration, because those observers apply SR,
> > > > > >
> > > > > > No. Their measurements are their measurements, their observations are
> > > > > > their observations. They are not applying SR in any way to make those
> > > > > > measurements.
> > > > > >
> > > > > > > which only takes into consideration the relative motion between them,
> > > > > > > and ignores the possibility that they could move at different
> > > > > > > velocities wrt a same rest frame (like the track wrt which two trains
> > > > > > > are moving). Then, one of them could view the other as longer.
> > > > > >
> > > > > > Not on your life. Not without making a *correction* that *you* are
> > > > > > imposing to their measurements. What SR predicts is what the observers
> > > > > > will measure *without* any correction or manipulation. That is the part
> > > > > > you fail to understand.
> > > > >
> > > > > What is the justification that an SR observer will measure all rod moving
> > > > > wrt him are contracted.
> > > >
> > > > In brief, the justification is that the *definition* of length relies
> > > > on simultaneity: the locations of the two ends of a moving rod must be
> > > > measured at the same time for the measurement to mean anything. The
> > > > problem is that there is no way to define absolute simultaneity. Two
> > > > events that are simultaneous to observer A will not be simultaneous to
> > > > observer B, and vice versa. Since simultaneity is a
> > > > reference-frame-dependent property, so is length. There is no deeper
> > > > physical meaning to the length of a rod. Now, if you'd like for me to
> > > > expand on this in detail, we can do that.
> > > >
> > > > > Also how do you know what the observer measure is
> > > > > what SR predicts??
> > > >
> > > > Uh, measurement, Ken. In an experiment.
> > >
> > > Could you propose a design for such experiment? I am looking forward to
> > > it.
> >
> > I don't have to propose it. It's already been measured numerous times.
> > See other post.
>
> When and where? By which experiment?
> Like most SRists, when in a corner, you try to escape responding.
> The truth is that length contraction has never been experimentally
> observed.

I described rapidity and experimental design in another post. And the
published papers about those experiments, some of which have been done
at Fermilab and Brookhaven National Lab, are widely available, as I
also pointed.

>
> Marcel Luttgens
>
>
> Marcel Luttgens

.