Re: Notable philosophical stupidity by the great SRian
- From: "Sorcerer" <Headmaster@xxxxxxxxxxxxxxxxxx>
- Date: Sun, 17 Sep 2006 18:31:34 GMT
"The Ghost In The Machine" <ewill@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:uac0u3-cjl.ln1@xxxxxxxxxxxxxxxxxxxxxxxxxx
| In sci.physics.relativity, Dirk Van de moortel
| <dirkvandemoortel@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
| wrote
| on Sun, 17 Sep 2006 12:07:56 GMT
| <wUaPg.81102$8I6.1103929@xxxxxxxxxxxxxxxxxxxxx>:
| >
| > "Mike" <eleatis@xxxxxxxx> wrote in message
news:1158454611.888394.36090@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
| >> Dirt Van Dar Mortal wrote:
| >>
| >> There is no experimental basis for preferring the classic over the
| >> relativistic formula. The only basis one could have for doing so, is
| >> purely philosophical...
| >>
| >>
| >>
http://groups.google.com/group/sci.physics.relativity/tree/browse_frm/thread/1578f5a779dce5a0/05cb66812171a136?rnum=31&hl=en&_done=%2Fgroup%2Fsci.physics.relativity%2Fbrowse_frm%2Fthread%2F1578f5a779dce5a0%3Fscoring%3Dd%26hl%3Den%26&scoring=d#doc_b3e0835f62ff4c0e
| >>
| >>
| >> Socrates and Plato are very proud of you Dirt. You are a good
| >> philosophy student. Probably, those are the only courses you passed.
| >>
| >>
| >> Mike
| >
| > And in context and with a less silly pointer:
| >
http://groups.google.com/group/sci.physics.relativity/msg/b3e0835f62ff4c0e
| >
| >> The answer is NO. All measurements can take place from the frame at
| >> rest in the frame of the laboratory and relative speed only calculated
| >> using the velocity addition formula.
| >
| > Has anyone ever precisely measured directly the relative velocity
|
| Define "precisely". At the velocity of 10 m/s one gets an
| error (gamma - 1) of about 5.556 * 10^-16. For a solid
| beam 1m long the value of 5.556 * 10^-16 m is a small
| fraction of a nucleon.
|
| This is easily swamped by thermal effects, even were the beam
| platinum-iridium:
|
| http://www.goodfellow.com/csp/active/gfMaterialInfo.csp?MATID=PT02
|
| For every nano-K the beam expands by about 8.7 * 10^-15 m.
| (This is apparently what Miller ran into during his experiments.
| I don't know if he used this alloy, but this is one of the best
| alloys for thermal stabilization I for one know about -- since it
| was used for the standard meter bar, if I'm not mistaken.)
|
| http://library.thinkquest.org/3659/pertable/77.html
|
| indicates the specific heat of both platinum and iridium
| is 0.13 J g^-1 K^-1 or 130 J kg^-1 K^-1. If we assume
| 1 cm^2 cross section (a fairly slender dowel or bar)
| the mass of the beam will be about 2.156 kg;
| accelerating it to 10 m/s will require 107.8 J. If one
| then stops it and transfers the energy of friction into
| heating the beam (as opposed to bending it, twisting it,
| or making noises), one raises the temperature thereof by
| 107.8 J / (130 J kg^-1 K^-1 * 2.156 kg) = 0.385 K.
|
| Small wonder one cannot directly measure the length compression.
| However, one can easily measure it indirectly by mounting a laser
| or transmitter on the moving object, and measuring the wavelength
| of that laser or transmitter from the laboratory rest frame.
| This can be done in a multitude of ways -- GPS is one, and
| stellar spectral observations are another.
|
| Given sufficient speed one can easily measure the ratio of
| wavelengths: 1, (c+v)/c, or sqrt(1+v/c)/sqrt(1-v/c). The first
| is predicted by "frictionless aether" theory; the second by
| rigid aether theory with an observer motionless with respect
| to the aether; the third by SR.
|
| Of course 10 m/s isn't quite sufficient in this case. ;-)
|
| > between two moving objects at every-day-life velocities, and
| > found a difference between the result of the classic velocity
| > addition formula and the relativistic velocity composition formula?
| > To use your words: "The answer is NO".
| > No one has done an experiment where a velocity of 10 m/s was
| > combined with a velocity of 10 m/s, which gave exactly
| > 20.00000000000000 m/s like predicted by the classic theory, as
| > opposed to the 19.99999999999998 m/s that is predicted by
| > relativity theory.
| > There is no experimental basis for preferring the classic over the
| > relativistic formula.
|
| Certainly not at *these* speeds. :-)
Take me to see the tachyon, dad.
I'm so excited, 27 km in 1/11245 secs.
Are we there yet?
Are we there yet?
Are we there yet?
Are we there yet?
Are we there yet?
Androcles
.
- References:
- Notable philosophical stupidity by the great SRian
- From: Mike
- Re: Notable philosophical stupidity by the great SRian
- From: Dirk Van de moortel
- Re: Notable philosophical stupidity by the great SRian
- From: The Ghost In The Machine
- Notable philosophical stupidity by the great SRian
- Prev by Date: Re: Notable philosophical stupidity by the great SRian
- Next by Date: Re: The Twin Paradox explained from the moving twin ?
- Previous by thread: Re: Notable philosophical stupidity by the great SRian
- Next by thread: "Another Rebuff to General Relativity By Cosmological Observations"
- Index(es):
Relevant Pages
|
