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Article #1027

Re: EINSTEINIANA ON THE CUSP OF A REVOLUTION AGAIN

#1027
From: Pentcho Valev
Date: Thu, 22 Oct 2009 06:01
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It seems Einsteinians find the new revolution more serious than
previous revolutions:

http://www.newscientist.com/article/mg20427314.400-rethinking-relativity-is-time-out-of-joint.html
"To look for potential deviations from general relativity, Bean
reanalysed the data and dropped the requirement that these two
components of gravity had to be equal. Instead the ratio of the two
was allowed to change in value. She found that between 8 and 11
billion years ago gravity's distortion of time appeared to be three
times as strong as its ability to curve space."

This sounds like "She found that between 8 and 11 million years ago
the greenness of crocodiles appeared to be three times as great as
their length". Yet there is something very positive in the new
revolution: Einsteinians obviously have decided to take more notice,
although in an idiotic way, of what John Norton, the cleverest
Einsteinian, has hinted at recently:

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."

That is, in the end Einsteiniana may put an end to the painful
destruction of human rationality caused by Einstein's time-is-an-
illusion discovery:

http://www.salem-news.com/articles/june232009/einstein_lessons_dj_6-22-09.php
"For those of us who believe in physics, this separation between past,
present and future is only an illusion, however tenacious" - Albert
Einstein

http://www.geekitude.com/gl/public_html/article.php?story=20050422141509987
Brian Greene: "I certainly got very used to the idea of relativity,
and therefore I can go into that frame of mind without it seeming like
an effort. But I feel and think about the world as being organized
into past, present and future. I feel that the only moment in time
that's really real is this moment right now. And I feel [that what
happened a few moments ago] is gone, and the future is yet to be. It
still feels right to me. But I know in my mind intellectually that's
wrong. Relativity establishes that that picture of the universe is
wrong, and if I work hard, I can force myself to recognize the fallacy
in my view or thinking; but intuitively it's still what I feel. So
it's a daily struggle to keep in mind how the world works, and
juxtapose that with experience that [I get] a thousand, even million
times a day from ordinary comings and goings."

Pentcho Valev wrote:

http://blogs.discovermagazine.com/cosmicvariance/2009/10/12/a-new-challenge-to-einstein/
"So here is a new such test, courtesy of Rachel Bean of Cornell. She
combines a suite of cosmological data, especially measurements of weak
gravitational lensing from the Hubble Space Telescope, to see whether
GR correctly describes the behavior of large-scale structure in the
universe. And the surprising thing is it doesnt. At the 98% confidence
level, Rachel finds that general relativity is inconsistent with the
data. I'm not sure why we haven't been reading about this in the
science media or even on other blogs it's certainly a newsworthy
result. Admittedly, the smart money is still that there is some tricky
thing that hasn't yet been noticed and Einstein will eventually come
through the victor, but this is serious work by a respected
cosmologist. Either the result is wrong, and we should be working hard
to find out why, or it's right, and we're on the cusp of a
revolution."

Other recent revolutions in Einsteiniana:

http://www.telegraph.co.uk/science/6057362/Give-scientists-the-freedom-to-be-wrong.html
Martin Rees: "Over the past week, two stories in the press have
suggested that scientists have been very wrong about some very big
issues. First, a new paper seemed to suggest that dark energy the
mysterious force that makes up three quarters of the universe, and is
pushing the galaxies further apart might not even exist."

http://www.sciscoop.com/story/2008/10/30/41323/484
"Does the apparently constant speed of light change over the vast
stretches of the universe? Would our understanding of black holes,
ancient supernovae, dark matter, dark energy, the origins of the
universe and its ultimate fate be different if the speed of light were
not constant?.....Couldn't it be that the supposed vacuum of space is
acting as an interstellar medium to lower the speed of light like some
cosmic swimming pool?"

Past revolutions in Einsteiniana:

http://www.prospectmagazine.co.uk/2003/04/waseinsteinwrong/
Paul Davies: "Was Einstein wrong? Einstein's famous equation E=mc2 is
the only scientific formula known to just about everyone. The "c" here
stands for the speed of light. It is one of the most fundamental of
the basic constants of physics. Or is it? In recent years a few
maverick scientists have claimed that the speed of light might not be
constant at all. Shock, horror! Does this mean the next Great
Revolution in Science is just around the corner?"

http://www.freerepublic.com/focus/f-news/519406/posts
"A GROUP of astronomers and cosmologists has warned that the laws
thought to govern the universe, including Albert Einstein's theory of
relativity, must be rewritten. The group, which includes Professor
Stephen Hawking and Sir Martin Rees, the astronomer royal, say such
laws may only work for our universe but not in others that are now
also thought to exist. "It is becoming increasingly likely that the
rules we had thought were fundamental through time and space are
actually just bylaws for our bit of it," said Rees, whose new book,
Our Cosmic Habitat, is published next month. "Creation is emerging as
even stranger than we thought." Among the ideas facing revision is
Einstein's belief that the speed of light must always be the same -
186,000 miles a second in a vacuum. There is growing evidence that
light moved much faster during the early stages of our universe. Rees,
Hawking and others are so concerned at the impact of such ideas that
they recently organised a private conference in Cambridge for more
than 30 leading cosmologists."

http://www.edge.org/3rd_culture/smolin03/smolin03_print.html
Lee Smolin: "Now, here is the really interesting part: Some of the
effects predicted by the theory appear to be in conflict with one of
the principles of Einstein's special theory of relativity, the theory
that says that the speed of light is a universal constant. It's the
same for all photons, and it is independent of the motion of the
sender or observer. How is this possible, if that theory is itself
based on the principles of relativity? The principle of the constancy
of the speed of light is part of special relativity, but we quantized
Einstein's general theory of relativity.....But there is another
possibility. This is that the principle of relativity is preserved,
but Einstein's special theory of relativity requires modification so
as to allow photons to have a speed that depends on energy. The most
shocking thing I have learned in the last year is that this is a real
possibility. A photon can have an energy-dependent speed without
violating the principle of relativity! This was understood a few years
ago by Amelino Camelia. I got involved in this issue through work I
did with Joao Magueijo, a very talented young cosmologist at Imperial
College, London. During the two years I spent working there, Joao kept
coming to me and bugging me with this problem.....These ideas all
seemed crazy to me, and for a long time I didn't get it. I was sure it
was wrong! But Joao kept bugging me and slowly I realized that they
had a point. We have since written several papers together showing how
Einstein's postulates may be modified to give a new version of special
relativity in which the speed of light can depend on energy."

Pentcho Valev
pvalev@yahoo.com
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From: Pentcho Valev <pvalev@yahoo.com>
Newsgroups: sci.physics.relativity,sci.physics,fr.sci.physique,fr.sci.astrophysique
Subject: Re: EINSTEINIANA ON THE CUSP OF A REVOLUTION AGAIN
Date: Wed, 21 Oct 2009 23:01:20 -0700 (PDT)
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