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From: Pentcho Valev on 20 Jul 2010 08:32
http://ffp11.gie.im/Scientific-Program
ELEVENTH INTERNATIONAL SYMPOSIUM
Frontiers of Fundamental Physics [FFP11]
6-9 July 2010 | Paris, France

Do you see signs, e.g. in the invited speakers' communications, that
Einstein's relativity is still alive? I don't. Even John Stachel, once
the most faithful Einsteinian, asks "Where is Knowledge?" and probably
gives an answer to himself: "In Newton's emission theory of light":

http://www.aip.org/history/einstein/essay-einstein-relativity.htm
This reprints an essay written ca. 1983, "'What Song the Syrens Sang':
How Did Einstein Discover Special Relativity?" in John Stachel,
Einstein from "B" to "Z".
"This was itself a daring step, since these methods had been developed
to help understand the behavior of ordinary matter while Einstein was
applying them to the apparently quite different field of
electromagnetic radiation. The "revolutionary" conclusion to which he
came was that, in certain respects, electromagnetic radiation behaved
more like a collection of particles than like a wave. He announced
this result in a paper published in 1905, three months before his SRT
paper. The idea that a light beam consisted of a stream of particles
had been espoused by Newton and maintained its popularity into the
middle of the 19th century. It was called the "emission theory" of
light, a phrase I shall use. (...) Giving up the ether concept allowed
Einstein to envisage the possibility that a beam of light was "an
independent structure," as he put it a few years later, "which is
radiated by the light source, just as in Newton's emission theory of
light." (...) An emission theory is perfectly compatible with the
relativity principle. Thus, the M-M experiment presented no problem;
nor is stellar abberration difficult to explain on this basis. (...)
This does not imply that Lorentz's equations are adequate to explain
all the features of light, of course. Einstein already knew they did
not always correctly do so-in particular in the processes of its
emission, absorption and its behavior in black body radiation. Indeed,
his new velocity addition law is also compatible with an emission
theory of light, just because the speed of light compounded with any
lesser velocity still yields the same value. If we model a beam of
light as a stream of particles, the two principles can still be
obeyed. A few years later (1909), Einstein first publicly expressed
the view that an adequate future theory of light would have to be some
sort of fusion of the wave and emission theories. (...) The resulting
theory did not force him to choose between wave and emission theories
of light, but rather led him to look forward to a synthesis of the
two."

Pentcho Valev
pvalev(a)yahoo.com
From: Pentcho Valev on 21 Jul 2010 01:00
Einstein's children in France used to denounce Poincaré's principle of
diversity of theoretical representations and fiercely defend
Einstein's principle of uniqueness of theoretical representations:

http://www.academie-sciences.fr/membres/in_memoriam/Generalites/Darrigol%20_amp.pdf
Olivier Darrigol: "Seul Einstein eut l'audace de déclarer que les
divers référentiels inertiels étaient entièrement équivalents, que les
temps et les espaces mesurés dans chacun d'entre eux étaient tous sur
le même pied. Il se persuada d'une exacte validité du principe de
relativité vers 1901, avant d'avoir lu Poincaré. Contrairement à ce
dernier, il accompagnait cette conviction du rejet du concept d'éther,
au nom d'un principe épistémologique d'univocité des représentations
théoriques : à un seul et même phénomène devait correspondre une seule
représentation théorique."

Einstein's relativity has come to an end but Einstein's children have
to eat - they are Poincaré's children now and denounce Einstein's
principle of uniqueness of theoretical representations and fiercely
defend Poincaré's principle of diversity of theoretical
representations:

http://www.rehseis.cnrs.fr/spip.php?article570
Olivier Darrigol: "L'étonnante diversité des descriptions théoriques
utilisées dans la physique d'hier et d'aujourd'hui est souvent perçue
comme une faiblesse temporaire qu'il faudra corriger dans un état plus
avancé de cette science. A l'opposé de cette attitude, les héritiers
de Maxwell, de Boltzmann et de Poincaré soulignent les vertus
épistémiques d'une diversité des descriptions et considèrent que
décrire est un acte dont la dynamique transcende les objets originels
de la description. Nous proposons de les suivre en explorant la
manière dont les divers modes, niveaux et ordres de description
dépendent des cultures scientifiques dans lesquels ils apparaissent et
affectent notre capacité à résoudre des problèmes concrets, nous
poussent à étudier de nouvelles sortes de phénomènes et suggèrent de
nouveaux objets physiques."

Pentcho Valev wrote:

http://ffp11.gie.im/Scientific-Program
ELEVENTH INTERNATIONAL SYMPOSIUM
Frontiers of Fundamental Physics [FFP11]
6-9 July 2010 | Paris, France

Do you see signs, e.g. in the invited speakers' communications, that
Einstein's relativity is still alive? I don't. Even John Stachel, once
the most faithful Einsteinian, asks "Where is Knowledge?" and probably
gives an answer to himself: "In Newton's emission theory of light":

http://www.aip.org/history/einstein/essay-einstein-relativity.htm
This reprints an essay written ca. 1983, "'What Song the Syrens Sang':
How Did Einstein Discover Special Relativity?" in John Stachel,
Einstein from "B" to "Z".
"This was itself a daring step, since these methods had been developed
to help understand the behavior of ordinary matter while Einstein was
applying them to the apparently quite different field of
electromagnetic radiation. The "revolutionary" conclusion to which he
came was that, in certain respects, electromagnetic radiation behaved
more like a collection of particles than like a wave. He announced
this result in a paper published in 1905, three months before his SRT
paper. The idea that a light beam consisted of a stream of particles
had been espoused by Newton and maintained its popularity into the
middle of the 19th century. It was called the "emission theory" of
light, a phrase I shall use. (...) Giving up the ether concept allowed
Einstein to envisage the possibility that a beam of light was "an
independent structure," as he put it a few years later, "which is
radiated by the light source, just as in Newton's emission theory of
light." (...) An emission theory is perfectly compatible with the
relativity principle. Thus, the M-M experiment presented no problem;
nor is stellar abberration difficult to explain on this basis. (...)
This does not imply that Lorentz's equations are adequate to explain
all the features of light, of course. Einstein already knew they did
not always correctly do so-in particular in the processes of its
emission, absorption and its behavior in black body radiation. Indeed,
his new velocity addition law is also compatible with an emission
theory of light, just because the speed of light compounded with any
lesser velocity still yields the same value. If we model a beam of
light as a stream of particles, the two principles can still be
obeyed. A few years later (1909), Einstein first publicly expressed
the view that an adequate future theory of light would have to be some
sort of fusion of the wave and emission theories. (...) The resulting
theory did not force him to choose between wave and emission theories
of light, but rather led him to look forward to a synthesis of the
two."

Pentcho Valev
pvalev(a)yahoo.com
From: Pentcho Valev on 9 Aug 2010 10:14
The current fashion in Einsteiniana: Hinting at the end of Einstein's
relativity by denouncing the space-time idiocy:

http://www.newscientist.com/article/mg20727721.200-rethinking-einstein-the-end-of-spacetime.html
NEW SCIENTIST: "Rethinking Einstein: The end of space-time. IT WAS a
speech that changed the way we think of space and time. The year was
1908, and the German mathematician Hermann Minkowski had been trying
to make sense of Albert Einstein's hot new idea - what we now know as
special relativity - describing how things shrink as they move faster
and time becomes distorted. "Henceforth space by itself and time by
itself are doomed to fade into the mere shadows," Minkowski
proclaimed, "and only a union of the two will preserve an independent
reality." And so space-time - the malleable fabric whose geometry can
be changed by the gravity of stars, planets and matter - was born. It
is a concept that has served us well, but if physicist Petr Horava is
right, it may be no more than a mirage. (...) Something has to give in
this tussle between general relativity and quantum mechanics, and the
smart money says that it's relativity that will be the loser."

http://www.homevalley.co.za/index.php?option=com_content&view=article&id=135:its-likely-that-times-are-changing
"Einstein introduced a new notion of time, more radical than even he
at first realized. In fact, the view of time that Einstein adopted was
first articulated by his onetime math teacher in a famous lecture
delivered one century ago. That lecture, by the German mathematician
Hermann Minkowski, established a new arena for the presentation of
physics, a new vision of the nature of reality redefining the
mathematics of existence. The lecture was titled Space and Time, and
it introduced to the world the marriage of the two, now known as
spacetime. It was a good marriage, but lately physicists passion for
spacetime has begun to diminish. And some are starting to whisper
about possible grounds for divorce. (...) Physicists of the 21st
century therefore face the task of finding the true reality obscured
by the spacetime mirage. (...) What he and other pioneers on the
spacetime frontiers have seen coming is an intellectual crisis. The
approaches of the past seem insufficiently powerful to meet the
challenges remaining from Einstein's century - such as finding a
harmonious mathematical marriage for relativity with quantum mechanics
the way Minkowski unified space and time. And more recently physicists
have been forced to confront the embarrassment of not knowing what
makes up the vast bulk of matter and energy in the universe. They
remain in the dark about the nature of the dark energy that drives the
universe to expand at an accelerating rate. Efforts to explain the
dark energy's existence and intensity have been ambitious but
fruitless. To Albrecht, the dark energy mystery suggests that it's
time for physics to drop old prejudices about how nature's laws ought
to be and search instead for how they really are. And that might mean
razing Minkowski's arena and rebuilding it from a new design. It seems
to me like it's a time in the development of physics, says Albrecht,
where it's time to look at how we think about space and time very
differently."

http://philsci-archive.pitt.edu/archive/00001661/
MINKOWSKI SPACE-TIME: A GLORIOUS NON-ENTITY
Harvey R. Brown, Oliver Pooley
"It is argued that Minkowski space-time cannot serve as the deep
structure within a "constructive" version of the special theory of
relativity, contrary to widespread opinion in the philosophical
community."

http://www.scientificamerican.com/article.cfm?id=is-time-an-illusion
Craig Callender in SCIENTIFIC AMERICAN: "Einstein mounted the next
assault by doing away with the idea of absolute simultaneity.
According to his special theory of relativity, what events are
happening at the same time depends on how fast you are going. The true
arena of events is not time or space, but their union: spacetime. Two
observers moving at different velocities disagree on when and where an
event occurs, but they agree on its spacetime location. Space and time
are secondary concepts that, as mathematician Hermann Minkowski, who
had been one of Einstein's university professors, famously declared,
"are doomed to fade away into mere shadows." And things only get worse
in 1915 with Einstein's general theory of relativity, which extends
special relativity to situations where the force of gravity operates.
Gravity distorts time, so that a second's passage here may not mean
the same thing as a second's passage there. Only in rare cases is it
possible to synchronize clocks and have them stay synchronized, even
in principle. You cannot generally think of the world as unfolding,
tick by tick, according to a single time parameter. In extreme
situations, the world might not be carvable into instants of time at
all. It then becomes impossible to say that an event happened before
or after another."

http://www.newscientist.com/article/mg20026831.500-what-makes-the-universe-tick.html
"General relativity knits together space, time and gravity.
Confounding all common sense, how time passes in Einstein's universe
depends on what you are doing and where you are. Clocks run faster
when the pull of gravity is weaker, so if you live up a skyscraper you
age ever so slightly faster than you would if you lived on the ground
floor, where Earth's gravitational tug is stronger. "General
relativity completely changed our understanding of time," says Carlo
Rovelli, a theoretical physicist at the University of the
Mediterranean in Marseille, France. (...) It is still not clear who is
right, says John Norton, a philosopher based at the University of
Pittsburgh, Pennsylvania. Norton is hesitant to express it, but his
instinct - and the consensus in physics - seems to be that space and
time exist on their own. The trouble with this idea, though, is that
it doesn't sit well with relativity, which describes space-time as a
malleable fabric whose geometry can be changed by the gravity of
stars, planets and matter."

http://www.pitt.edu/~jdnorton/Goodies/passage/index.html
John Norton: "A common belief among philosophers of physics is that
the passage of time of ordinary experience is merely an illusion. The
idea is seductive since it explains away the awkward fact that our
best physical theories of space and time have yet to capture this
passage. I urge that we should resist the idea. We know what illusions
are like and how to detect them. Passage exhibits no sign of being an
illusion....Following from the work of Einstein, Minkowski and many
more, physics has given a wonderfully powerful conception of space and
time. Relativity theory, in its most perspicacious form, melds space
and time together to form a four-dimensional spacetime. The study of
motion in space and and all other processes that unfold in them merely
reduce to the study of an odd sort of geometry that prevails in
spacetime. In many ways, time turns out to be just like space. In this
spacetime geometry, there are differences between space and time. But
a difference that somehow captures the passage of time is not to be
found. There is no passage of time. There are temporal orderings. We
can identify earlier and later stages of temporal processes and
everything in between. What we cannot find is a passing of those
stages that recapitulates the presentation of the successive moments
to our consciousness, all centered on the one preferred moment of
"now." At first, that seems like an extraordinary lacuna. It is, it
would seem, a failure of our best physical theories of time to capture
one of time's most important properties. However the longer one works
with the physics, the less worrisome it becomes. (...) I was, I
confess, a happy and contented believer that passage is an illusion.
It did bother me a little that we seemed to have no idea of just how
the news of the moments of time gets to be rationed to consciousness
in such rigid doses. (...) Now consider the passage of time. Is there
a comparable reason in the known physics of space and time to dismiss
it as an illusion? I know of none. The only stimulus is a negative
one. We don't find passage in our present theories and we would like
to preserve the vanity that our physical theories of time have
captured all the important facts of time. So we protect our vanity by
the stratagem of dismissing passage as an illusion."

Pentcho Valev
pvalev(a)yahoo.com
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