Re: Why is the speed of light as it is

From: Henri Wilson (H_at_..(Henri)
Date: 11/27/04 

Date: Sat, 27 Nov 2004 21:58:01 GMT

On Sat, 27 Nov 2004 05:00:06 GMT, The Ghost In The Machine
<ewill@sirius.athghost7038suus.net> wrote:

>In sci.physics.relativity, Henri Wilson
><H@.>
> wrote
>on Fri, 26 Nov 2004 21:05:53 GMT
><dj6fq0d1s6dj13ubfng3hd10fgj0q1f23t@4ax.com>:
>> On Fri, 26 Nov 2004 04:01:18 GMT, The Ghost In The Machine
>> <ewill@sirius.athghost7038suus.net> wrote:
>>
>>>In sci.physics.relativity, Henri Wilson
>>><H@.>
>>> wrote
>>>on Thu, 25 Nov 2004 21:20:27 GMT
>>><u0jcq05h63dgo4gid163vm0aerjoe5nmrb@4ax.com>:
>>>> On 25 Nov 2004 03:13:50 -0800, fsegg@uaf.edu (Eric Gisse) wrote:
>>>>
>>>>>H@..(Henri Wilson) wrote in message news:<450bq01v8n80aecu8cmunlo0t4tnvto7s5@4ax.com>...
>>>
>>>[snippage]
>>>
>>>>>> How many times do I have to tell you that 'the speed of light' is
>>>>>> a nonsense term.
>>>>>>
>>>>>> Speed must be specified relative to something else.
>>>>>>
>>>>>> Now, have you learnt anything today Geese?
>>>>>
>>>>>That answering my simple request is harder than making up
>>>>>bull*** non-sequiturs?
>>>>>
>>>>>If you can't do it, just say so.
>>>>
>>>> Geese. Please tell our 'failed-first-semester' friend Evens what you have
>>>> learnt from me today.
>>>> He doesn't understand either.
>>>>
>>>> There is no 'speed of light'.
>>>> There is no 'speed of anything'.
>>>
>>
>>>Tell that to the friendly traffic cop on the motorbike next time
>>>he flags you for speeding. We'll wait... :-)
>>
>> Ghost, will he be interested in my speed wrt the road or
>> wrt alpha centauri?
>
>
>The Earth road, of course.
>
>I should mention that one's speed can be measured via lightwaves;
>the method involves pointing a "radar gun" and measuring the
>frequency change of the returning waves.
>
>Assuming a frequency of 24.050 GHz and a speed of 30 m/s (10^-7 c,
>about 67.1 mph or 108 kph), the frequency shift should be
>approximately 2405 Hz; in any event field calibration does not
>look to be overly difficult, given a discriminator similar to
>those found in common FM radios. (The main difference: a radar
>discriminator must use DC coupling, as the value appears as a
>generally DC signal, although artifacts are possible if the
>waves hit the tires, AFAICT.)
>
>Second-order effects because of relativity appear to be on the
>order of 240.5 microherts -- that's more than an hour in duration.
>
>A more sophicated unit might be attuned to the cruiser's speedometer.
>Here's where relativity rears its little head -- and it's very
>little, as the error in assuming Newtonian physics is on the
>order of 10^-14; don't expect to get one's ticket dismissed
>that way! The most straightforward computation is v_t = v_m + v_c,
>where v_t is the speed of the guy about to be waved over,
>v_m is the measured speed of the car, relative to the cruiser,
>and v_c is the cruiser's speedometer indication, which (presumably)
>is the cruiser's speed relative to the roadway.
>
>The correct (if slightly pointless) SR computation would of
>course be v_t = (v_m + v_c) / (1 + v_m * v_c / c^2).
>
>I'd worry more about tire wear. :-) Presumably, that
>introduces an error of about 10^-4.

Radar speed cameras certainly do not have to include any relativistic effects
even if such existed...which they don't.

>
>Now, as far as lightspeed is concerned -- Fizeau's wheel is
>probably the most illustrative. Basically, a beam is led
>through a toothed wheel, in such a fashion that the teeth
>alternately block it, and let it pass. The chopped beam
>then feeds through a mirror system to induce a delay, and
>then back through the wheel in the same path as it took
>going out. Done correctly, the spinning of the wheel can
>be used to totally block the beam, and the lightspeed can
>be computed from the known lightpath, the number of teeth
>on the wheel, and the rotational speed of the wheel.

Fizeau's method epitomizes a TWLS measurement.
The fact that TWLS appears to be dead constant is string evidence in support of
the ballistic theory.

>
>It is not clear to me whether lightsources other than
>a stationary laser (or maybe just a strong arc-lamp)
>have been attempted or not, but the result, according to
>SR, is the same speed: 299792458 m/s. One interesting
>measurement might be using the light of Venus through
>Fizeau's apparatus, during the times when Venus is in
>its first or third quarter phases. However, Fizeau's
>apparatus may not be quite precise enough, as the delta
>is on the order of 5 * 10^-5 c or thereabouts.

I have suggested an experiment of this nature using red and blue shifted light
from stars. The light would have to be sent through an optical gate on the
moon.
Even then, it would be hard to detect differences between c and c+v.

>
>The actual delta, if SR predictions are correct, is of course 0.

haha!

>
>[.sigsnip]

HW.

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

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