Re: The Cosmological Principle

oriel36 wrote: 
Sam

You love your relativistic homocentricity which is the natural
progression  and expansion of the original Newtonian  quasi-geocentric
framehopping to an observer on the Sun.

By the early 20th century the whole thing was in such a mess that the
basis for homocentricity was borrowed from a  well known 1898 science
fiction novel by  H.G Wells.

"'Scientific people,' proceeded the Time Traveller, after the pause
required for the proper assimilation of this, 'know very well that
Time is only a kind of Space."

http://www.bartleby.com/1000/1.html

The exquisite reasoning of the Copernican/Keplerian astronomers is
before you and with time lapse footage of Saturn and Jupiter to make
enjoyment really possible you and your colleagues,knowing no better,opt
for a dumb Newtonian view.

How does it feel to follow  concepts found in a science fiction novel
and then pass them off as a ' human achievement'. It was an achievement
foir Well's fictional narrative but goodness me,to believe it as you
lot  do is embarrassing.

And all because Newton started that framehopping to the Sun in
attempting to explain apparent  retrograde motion !.


  Then guess what happened....

Miraculous Year (1905)

Poincaré & Einstein
Ref: "EINSTEIN 1905", John S. Rigden, Harvard University Press (2005)

  In his 1902 book "La Science et l'Hypothèse", the
  mathematical physicist Henri Poincaré identified three
  fundamental yet unresolved problems [in physics].

  One problem concerned the mysterious way ultraviolet
  light ejects electrons from the surface of a metal;

  the second problem was the zig-zagging perpetual motion
  of pollen particles suspended in a liquid;

  the third problem was the failure of experiments to
  detect Earth's motion through the aether.

  In 1904, Einstein read Poincaré's book. He had also been
  thinking about these problems, independently of Poincaré.
  For Einstein, they were clearly part of God's thoughts.
  One year later, in 1905, he solved all three.

            _______________________


Ref: http://physicsweb.org/articles/world/18/1/2/1
Adapted from "Five papers that shook the world"
by Matthew Chalmers
January 2005

  Most physicists would be happy to make one discovery that
  is important enough to be taught to future generations of
  physics students. Only a very small number manage this in
  their lifetime, and even fewer make two appearances in
  the textbooks.

  But Einstein was different. In little more than eight
  months in 1905 he completed five papers that would change
  the world for ever. Spanning three quite distinct topics
  - relativity, the photoelectric effect and Brownian
  motion - Einstein overturned our view of space and time,
  showed that it is insufficient to describe light purely
  as a wave, and laid the foundations for the discovery of
  atoms.


  Genius at work

  Perhaps even more remarkably, Einstein's 1905 papers were
  based neither on hard experimental evidence nor
  sophisticated mathematics. Instead, he presented elegant
  arguments and conclusions based on physical intuition.

  "Einstein's work stands out not because it was difficult
  but because nobody at that time had been thinking the way
  he did," says Gerard 't Hooft of the University of
  Utrecht, who shared the 1999 Nobel Prize for Physics for
  his work in quantum theory.

  "Dirac, Fermi, Feynman and others also made multiple
  contributions to physics, but Einstein made the world
  realize, for the first time, that pure thought can change
  our understanding of nature."

  And just in case the enormity of Einstein's achievement
  is in any doubt, we have to remember that he did all of
  this in his "spare time".

  Statistical revelations

  In 1905 Einstein was married with a one-year-old son and
  working as a patent examiner in Bern in Switzerland. His
  passion was physics, but he had been unable to find an
  academic position after graduating from the ETH in Zurich
  in 1900.

  Nevertheless, he had managed to publish five papers in
  the leading German journal Annalen der Physik between
  1900 and 1904, and had also submitted an unsolicited
  thesis on molecular forces to the University of Zurich,
  which was rejected.

  Most of these early papers were concerned with the
  reality of atoms and molecules, something that was far
  from certain at the time. But on 17 March in 1905 - three
  days after his 26th birthday - Einstein submitted a paper
  titled "A heuristic point of view concerning the
  production and transformation of light" to Annalen der
  Physik.

  Einstein suggested that, from a thermodynamic
  perspective, light can be described as if it consists of
  independent quanta of energy (Ann. Phys., Lpz 17
  132-148).

  This hypothesis, which had been tentatively proposed by
  Max Planck a few years earlier, directly challenged the
  deeply ingrained wave picture of light. However, Einstein
  was able to use the idea to explain certain puzzles about
  the way that light or other electromagnetic radiation
  ejected electrons from a metal via the photoelectric
  effect.

  Maxwell's electrodynamics could not, for example, explain
  why the energy of the ejected photoelectrons depended
  only on the frequency of the incident light and not on
  the intensity. However, this phenomenon was easy to
  understand if light of a certain frequency actually
  consisted of discrete packets or photons all with the
  same energy.

  Einstein would go on to receive the 1921 Nobel Prize for
  Physics for this work, although the official citation
  stated that the prize was also awarded "for his services
  to theoretical physics".

  "The arguments Einstein used in the photoelectric and
  subsequent radiation theory are staggering in their
  boldness and beauty," says Frank Wilczek, a theorist at
  the Massachusetts Institute of Technology who shared the
  2004 Nobel Prize for Physics.

  "He put forward revolutionary ideas that both inspired
  decisive experimental work and helped launch quantum
  theory." Although not fully appreciated at the time,
  Einstein's work on the quantum nature of light was the
  first step towards establishing the wave-particle duality
  of quantum particles.

  On 30 April, one month before his paper on the
  photoelectric effect appeared in print, Einstein
  completed his second 1905 paper, in which he showed how
  to calculate Avogadro's number and the size of molecules
  by studying their motion in a solution.

  This article was accepted as a doctoral thesis by the
  University of Zurich in July, and published in a slightly
  altered form in Annalen der Physik in January 1906.

  Despite often being obscured by the fame of his papers on
  special relativity and the photoelectric effect,
  Einstein's thesis on molecular dimensions became one of
  his most quoted works.

  Indeed, it was his preoccupation with statistical
  mechanics that formed the basis of several of his
  breakthroughs, including the idea that light was
  quantized.

  After finishing a doctoral thesis, most physicists would
  be either celebrating or sleeping. But just 11 days later
  Einstein sent another paper to Annalen der Physik, this
  time on the subject of Brownian motion.

  In this paper, "On the movement of small particles
  suspended in stationary liquids required by the
  molecular-kinetic theory of heat", Einstein combined
  kinetic theory and classical hydrodynamics to derive an
  equation that showed that the displacement of Brownian
  particles varies as the square root of time (Ann. Phys.,
  Lpz 17 549-560).

  This was confirmed experimentally by Jean Perrin three
  years later, proving once and for all that atoms do
  exist. In fact, Einstein extended his theory of Brownian
  motion in an additional paper that he sent to the journal
  on 19 December, although this was not published until
  February 1906.

  A special discovery

  Shortly after finishing his paper on Brownian motion
  Einstein had an idea about synchronizing clocks that were
  spatially separated.

            _______________________


Adapted from "The Mechanical Universe"
Episode 43: Velocity and Time

  In the 1800s Michael Faraday discovered, or I should say
  formalized, electromagnetic induction. Given a coil of
  wire and a bar magnet...


             F = qE + qv x B


  Holding the coil stationary and moving the bar magnet
  produced an electric current in the coil. Similarly
  holding the bar magnet stationary and moving the coil
  also produced an electric current in the coil.

  But in the language of electrodynamics of the day the two
  cases were distinct independent phenomena that had
  completely different explanations.

  When Albert Einstein saw that, he said "Look guys, you've
  just got to be kidding--Any yo-yo can see that these are
  the same thing".

  So it was this little experiment that was really the
  start of relativity, not the Michelson-Morley
  Experiment--not some exotic experiment to detect the
  motion of the earth through the aether.

  With this simple little phenomenon, that of course
  everybody knew about, disturbed nobody else, but Albert
  Einstein.

  This led him to write a paper that landed on the desks of
  Annalen der Physik on 30 June, and would go on to
  completely overhaul our understanding of space and time.
  Some 30 pages long and containing no references, his
  fourth 1905 paper was titled "On the electrodynamics of
  moving bodies" (Ann. Phys., Lpz 17 891-921).

  In the 200 or so years before 1905, physics had been
  built on Newton's laws of motion, which were known to
  hold equally well in stationary reference frames and in
  frames moving at a constant velocity in a straight line.
  Provided the correct "Galilean" rules were applied, one
  could therefore transform the laws of physics so that
  they did not depend on the frame of reference.

  However, the theory of electrodynamics developed by
  Maxwell in the late 19th century posed a fundamental
  problem to this "principle of relativity" because it
  suggested that electromagnetic waves always travel at the
  same speed.

  Either electrodynamics was wrong or there had to be some
  kind of stationary "ether" through which the waves could
  propagate.

            _______________________


  I just want to read to you the first few paragraphs of
  Einsteins 4th paper...

ON THE ELECTRODYNAMICS OF MOVING BODIES
By A. Einstein
June 30, 1905

  It is known that Maxwell's electrodynamics--as usually
  understood at the present time--when applied to moving
  bodies, leads to asymmetries which do not appear to be
  inherent in the phenomena.

  Take, for example, the reciprocal electrodynamic action
  of a magnet and a conductor. The observable phenomenon
  here depends only on the relative motion of the conductor
  and the magnet, whereas the customary view draws a sharp
  distinction between the two cases in which either the one
  or the other of these bodies is in motion. For if the
  magnet is in motion and the conductor at rest, there
  arises in the neighbourhood of the magnet an electric
  field with a certain definite energy, producing a current
  at the places where parts of the conductor are situated.

  But if the magnet is stationary and the conductor in
  motion, no electric field arises in the neighbourhood of
  the magnet. In the conductor, however, we find an
  electromotive force, to which in itself there is no
  corresponding energy, but which gives rise--assuming
  equality of relative motion in the two cases
  discussed--to electric currents of the same path and
  intensity as those produced by the electric forces in the
  former case.

  Examples of this sort, together with the unsuccessful
  attempts to discover any motion of the earth relatively
  to the "light medium," suggest that the phenomena of
  electrodynamics as well as of mechanics possess no
  properties corresponding to the idea of absolute rest.

  They suggest rather that, as has already been shown to  (1)
  the first order of small quantities, the same laws of
  electrodynamics and optics will be valid for all frames
  of reference for which the equations of mechanics hold
  good. We will raise this conjecture (the purport of which
  will hereafter be called the ``Principle of Relativity'')
  to the status of a postulate,

  and also introduce another postulate, which is only     (2)
  apparently irreconcilable with the former, namely, that
  light is always propagated in empty space with a definite
  velocity c which is independent of the state of motion of
  the emitting body.

  These two postulates suffice for the attainment of a
  simple and consistent theory of the electrodynamics of
  moving bodies based on Maxwell's theory for stationary
  bodies.

  The introduction of a "luminiferous ether" will prove
  to be superfluous inasmuch as the view here to be
  developed will not require an "absolutely stationary
  space" provided with special properties, nor assign a
  velocity-vector to a point of the empty space in which
  electromagnetic processes take place.

  And, of course the paper goes on to develop the ideas
  and make his case...

            _______________________



  True to style, Einstein
  swept away the concept of the ether (which, in any case,
  had not been detected experimentally) in one audacious
  step. He postulated that no matter how fast you are
  moving, light will always appear to travel at the same
  velocity: the speed of light is a fundamental constant of
  nature that cannot be exceeded.

  Combined with the requirement that the laws of physics
  are the identical in all "inertial" (i.e.
  non-accelerating) frames, Einstein built a completely new
  theory of motion that revealed Newtonian mechanics to be
  an approximation that only holds at low, everyday
  speeds.

  The theory later became known as the special theory of
  relativity - special because it applies only to
  non-accelerating frames - and led to the realization that
  space and time are intimately linked to one another.

  In order that the two postulates of special relativity
  are respected, strange things have to happen to space and
  time, which, unbeknown to Einstein, had been predicted by
  Lorentz and others the previous year.

  For instance, the length of an object becomes shorter
  when it travels at a constant velocity, and a moving
  clock runs slower than a stationary clock.

  Effects like these have been verified in countless
  experiments over the last 100 years, but in 1905 the most
  famous prediction of Einstein's theory was still to come.

  After a short family holiday in Serbia, Einstein
  submitted his fifth and final paper of 1905 on 27
  September. Just three pages long and titled "Does the
  inertia of a body depend on its energy content?", this
  paper presented an "afterthought" on the consequences of
  special relativity, which culminated in a simple equation
  that is now known as E = mc^2 (Ann. Phys., Lpz 18
  639-641).

  This equation, which was to become the most famous in all
  of science, was the icing on the cake.

  "The special theory of relativity, culminating in the
  prediction that mass and energy can be converted into one
  another, is one of the greatest achievements in physics -
  or anything else for that matter," says Wilczek.

  "Einstein's work on Brownian motion would have merited a
  sound Nobel prize, the photoelectric effect a strong
  Nobel prize, but special relativity and E = mc^2 were
  worth a super-strong Nobel prize."

  However, while not doubting the scale of Einstein's
  achievements, many physicists also think that his 1905
  discoveries would have eventually been made by others.

  "If Einstein had not lived, people would have stumbled on
  for a number of years, maybe a decade or so, before
  getting a clear conception of special relativity," says
  Ed Witten of the Institute for Advanced Study in
  Princeton.

  't Hooft agrees. "The more natural course of events would
  have been that Einstein's 1905 discoveries were made by
  different people, not by one and the same person," he
  says. However, most think that it would have taken much
  longer - perhaps a few decades - for Einstein's general
  theory of relativity to emerge.

  Indeed, Wilczek points out that one consequence of
  general relativity being so far ahead of its time was
  that the subject languished for many years afterwards.

  The aftermath

  By the end of 1905 Einstein was starting to make a name
  for himself in the physics community, with Planck and
  Philipp Lenard - who won the Nobel prize that year -
  among his most famous supporters. Indeed, Planck was a
  member of the editorial board of Annalen der Physik at
  the time.

  Einstein was finally given the title of Herr Doktor from
  the University of Zurich in January 1906, but he remained
  at the patent office for a further two and a half years
  before taking up his first academic position at Zurich.

  By this time his statistical interpretation of Brownian
  motion and his bold postulates of special relativity were
  becoming part of the fabric of physics, although it would
  take several more years for his paper on light quanta to
  gain wide acceptance.

  1905 was undoubtedly a great year for physics, and for
  Einstein. "You have to go back to quasi-mythical figures
  like Galileo or especially Newton to find good
  analogues," says Wilczek.

  "The closest in modern times might be Dirac, who, if
  magnetic monopoles had been discovered, would have given
  Einstein some real competition!" But we should not forget
  that 1905 was just the beginning of Einstein's legacy.
  His crowning achievement - the general theory of
  relativity - was still to come.

.

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