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Author: Pentcho ValevPentcho Valev
Date: Sep 11, 2008 23:30
> Sean2008 gmail.com> wrote:>> What is the consensus of opinion in this discussion group about what
>> experiments might constitute the "cornerstone" experiments that
>> confirm Special Relativity? Or are there a set of such experiments?
>> In studying the results of various experiments there are, obviously,
>> many that repeat experimental designs, the only purpose of which is to
>> improve the accuracy of measurement. For my own education, I would be
>> interested in what set of experiments might be considered fundamental
>> and if that set was fairly small.
>
> This depends a little on whether you want an "answer for a student" or
> an "answer for a working physicist." To learn special relativity, it makes
> sense to focus on a few "cornerstone" experiments testing basic principles.
> I have no quarrel with the suggestions you've heard so far.
>
> But all experiments have finite accuracies, and to physicist working in
> this field, the interesting question is how to push measurements beyond
> the existing limits. This sometimes means refining existing experiments:
> for example, cryogenic oscillators have allowed increasingly accurate ...
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Author: Axel HarveyAxel Harvey
Date: Sep 11, 2008 21:45
Spherical coordinates are radial (how far from the
centre), azimuthal (measured over 2*pi or 360°
around a reference great circle), and polar (between
+90° and -90° along arcs normal to the reference
great circle). Examples of azimuthal and polar are
longitude and latitude, or right ascension and
declination.
I am editing a text and would like to replace the word
"azimuthal", provided there is an alternative that
would be recognized by most readers. The reason is
that I want to avoid confusion between the terms
"azimuthal", which refers to spherical coordinate
systems in general, and "azimuth", which is a specific
azimuthal coordinate (measured around the
observer's horizon). Is there such an alternative
term?
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Author: HamadyHamady
Date: Sep 11, 2008 13:46
By: Dr. / Zaghloul El-Naggar
Then He rose over (Istawa) towards the heaven when it was smoke, and
said to it and to the earth:" Come both of you willingly or
unwillingly." They both said: "We come willingly."
(Surat Fussilat (They are explained in detail):11).
In the first third of the 20th century, astronomers noticed the
expansion of the universe, the thing that has aroused a lot of
controversy before scientists could admit it. The Glorious Qur'an
refers to this fact before 1400 years ago as Allah Says: "With power
did We construct the heaven. Verily, We are Able to extend the
vastness of space thereof."
(Surat Adh-Dhariyat (The Winds that Scatter):47).
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Author: Pentcho ValevPentcho Valev
Date: Sep 11, 2008 08:36
f'/f = c'/c
where f' is the shifted frequency of light (at the moment of
reception), f is the original frequency (at the moment of emission),
c' is the speed of light relative to the observer (at the moment of
reception), c is the speed of light relative to the emitter (at the
moment of emission).
Pentcho Valev
pvalev@ yahoo.com
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Author: BradGuthBradGuth
Date: Sep 11, 2008 05:41
> http://www.ng2000.com/fw.php?tp=astronomy
>
> Events on a cosmic scale are often barely discernible on Earth. This explains
> why astronomers are currently not able to prove directly that the universe is
> expanding at an ever increasing rate, nor can they search for planets that are
> roughly the same size as Earth and revolve around a sun-like star.
Gamma pulse producing stars are somewhat like a cosmic GPS network.
Earth sized planets may turn out being the exception rather than the
rule for accommodating other forms of complex life.
~ Brad Guth Brad_Guth Brad.Guth BradGuth BG
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Author: Pentcho ValevPentcho Valev
Date: Sep 11, 2008 05:40
On Sep 11, 1:32 pm, rich...@ cogsci.ed.ac.uk (Richard Tobin) wrote in
sci.physics: > In article ,
>
> Cwatters TurnersOakNOSPAM.plus.com> wrote:>>Why send particles both ways around the ring if they can only ever collide
>>at less than the speed of light?
>
> They collide nearer to the speed of light! When you're very near the
> speed of light, a tiny increase in speed corresponds to a large
> increase in energy.
Yet Waters' question has a curious implication. The changes produced
by the collision of photons (travelling at c relative to some inertial
system) with anything travelling in the opposite direction at v
(relative to the same inertial system, that is, in this system the
relative speed is measured to be c+v) should be independent of the
speed v of the "anything". Simply because, according to Divine
Albert's Divine Special Relativity, the "anything" should always see
the photons approaching it at c.
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Author: Pentcho ValevPentcho Valev
Date: Sep 11, 2008 03:56
On Sep 11, 11:02 am, "harry"
wrote in sci.physics.relativity:
> "John Kennaugh" notworking.freeserve.co.uk> wrote:>> I accept that that would be true if light was indeed a wave. It isn't. If
>> it were it could not possibly knock electrons out of a metal unless the
>> intensity was sufficient to make the metal hot enough to release thermal
>> electrons. Once you accept that light is particles and that the waves do
>> not physically exist then you have no need for a medium. Instead you need
>> to concentrate on trying to explain how photons can produce such a
>> convincing facsimile of a wave. Something seriously neglected by physics.
>> I believe that Waldron is on the right lines [1]
>
> Not only that, you would also have to explain how it...
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Author: Pentcho ValevPentcho Valev
Date: Sep 11, 2008 00:45
On Sep 11, 7:02 am, Tom Roberts sbcglobal.net> wrote in
sci.physics.relativity:> Sean2008 wrote:
>> What is the consensus of opinion in this discussion group about what
>> experiments might constitute the "cornerstone" experiments that
>> confirm Special Relativity? Or are there a set of such experiments?
>
>> In studying the results of various experiments there are, obviously,
>> many that repeat experimental designs, the only purpose of which is to
>> improve the accuracy of measurement. For my own education, I would be
>> interested in what set of experiments might be considered fundamental
>> and if that set was fairly small.
>
>> Hopefully, my question has not displayed too much ignorance regarding
>> the experimental evidence. This may, perhaps, be one of those
>> questions that is intrinsically unanswerable but I am too ignorant to
>> know!
>
> [Asking for a "consensus" is silly -- science is not
> determined by voting! The contributors to this newsgroup ...
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