Re: Are *observed* SR effects real?

On Jul 28, 8:40 am, mluttg...@xxxxxxxxxx wrote:
On Jul 28, 3:22 pm, PD <TheDraperFam...@xxxxxxxxx> wrote:



On Jul 28, 5:20 am, mluttg...@xxxxxxxxxx wrote:

On Jul 27, 9:10 pm, PD <TheDraperFam...@xxxxxxxxx> wrote:

On Jul 26, 8:02 am, mluttg...@xxxxxxxxxx wrote:

On Jul 25, 10:38 pm, PD <TheDraperFam...@xxxxxxxxx> wrote:

On Jul 25, 8:00 am, mluttg...@xxxxxxxxxx wrote:

I retain:

- If you stick to just the suppositions and the logic and never check
in
with reality, then of course it's going to seem just as easy to make
the opposite suppositions. But Nature settles the matter
*definitively*, in experiments designed to check which supposition is
actually right -- this one or that one.

- The strength of SR is not based on the plausibility of its
suppositions and the coherence of arguments that follow, but also on
verification with EXPERIMENT.

So, the obvious questions are:

How did Nature 'decided' that the length of the train is 600 m
in Stan's frame, and 800 m in Tom's frame, and not the
opposite?
(Such 'decision' being compatible with other experiments).

Is it because the train is moving relative to the Earth, and not
the opposite?

Doesn't such experimental verification falsify SR?

Not at all.

SR explicitly says that the laws of nature work out to demand this:
The physical length of an object is always largest in the frame in
which it is at rest.

This is *precisely* the result that Stan and Tom reproduce in their
measurements, and the result that is confirmed in literally scores of
experiments whose methods and results are recorded in the literature.

In the present case, the longest physical length of the train is the
one measured by Tom, in whose frame the train is at rest.

PD- Hide quoted text -

- Show quoted text -

I am wondering at which scores of experiments you
are referring to, see

http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.....
"7. Tests of Length Contraction
At this time there are no direct tests of length contraction, as
measuring the length of a moving object to the precision
required has not been feasible. There is, however,
a demonstration that it occurs:"

The *direct* test has not been done, but neither is it required. We
knew that the proton had constituents long before there was an
experiment that blew a proton apart and we saw the trails of the
constituents. Same for atoms.

There are a number of indirect but compelling experiments that show
that length contraction occurs at the rate predicted by SR, and this
is alluded to in the web FAQ above.

Right, no direct experiment has been made, but some
experimental results are coherent with the existence
of length contraction.

And now we've explored a little where length contraction comes from,
and it is neither the result of a physical interaction that physically
alters the object, nor is it an illusion stemming from optical
propagation delays.

Now, we were about to embark on the same frame-dependence of duration,
sometimes called "time dilation", and it will probably come as no
surprise that it is the result neither of a physical interaction that
physically alters a clock or timed process, nor is it an illusion
stemming from optical propagation delays.

Are you ready?


Marcel Luttgens

Some samples:
- density increase due to volume decrease due to length contraction in
nucleus-nucleus interactions at RHIC.
- uniformity of secondary particle rapidity distribution in
calorimeter segmentation following Lorentz contraction rules in both
fixed-target and collider energies at common root-s.
- elevation of harmonic oscillator ground states in crystal lattices
undergoing collective vibration, in accordance with Lorentz
contraction of the lattice spacing.

If you want to see how experimental evidence drives our confidence in
special relativity (as opposed to just plausible suppositions and
logical arguments), then I suggest you spend a few summer evenings in
the library, looking up and reading a number of experimental papers. I
think it would change your perspective on relativity and why we think
it's right. Why we think it's right has virtually *nothing* to do with
plausible suppositions, logical arguments, and gedankens.

PD

.

Relevant Pages

  • Re: Are *observed* SR effects real?
    ... the opposite suppositions. ... suppositions and the coherence of arguments that follow, ... in Stan's frame, and 800 m in Tom's frame, and not the ... At this time there are no direct tests of length contraction, ...
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  • Re: Are *observed* SR effects real?
    ... the opposite suppositions. ... suppositions and the coherence of arguments that follow, ... in Stan's frame, and 800 m in Tom's frame, and not the ... At this time there are no direct tests of length contraction, ...
    (sci.physics.relativity)
  • Re: Are *observed* SR effects real?
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    (sci.physics.relativity)
  • Re: Are *observed* SR effects real?
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  • Re: Are *observed* SR effects real?
    ... the opposite suppositions. ... suppositions and the coherence of arguments that follow, ... in Stan's frame, and 800 m in Tom's frame, and not the ... At this time there are no direct tests of length contraction, ...
    (sci.physics.relativity)
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