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From: Pentcho Valev on 9 Aug 2010 10:09
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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