Blunderov
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"We think in generalities, we live in details"
  
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RE: virus: Time out of mind
« on: 2006-02-25 06:58:14 » |
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[Blunderov] I'm encouraged by the material included below. I've been
wondering for some while whether time doesn't perhaps exist in all
directions at once, so to speak. And whether the universe that presents
itself to us is propelled (in what appears to be a forwards direction) by a
wave motion induced by a probability wave collapse.
The discovey of dark matter suggests to me that much of the Universe has
existential characteristics which are discreet to us, except by inference;
perhaps this is the case with time?
Best Regards.
[Bl.] (Can't find any additional material on this; the Stanford link is
broken. Tantalising.)
http://science.slashdot.org:80/science/06/02/05/006254.shtml
Posted by ScuttleMonkey on Saturday February 04, @08:33PM
from the high-time-to-check-it-out dept.
sciencenews writes to tell us that a physicist at Stanford has just recently
published a peer review website for several physics lectures focusing on a
single underlying idea that "time is not a single dimension of spacetime but
rather a local geometric distinction in spacetime." The science is presented
quite clearly and originally uses GPS systems as a point of focus. From the
article: "Not too long ago, people thought the Earth was flat, which meant
they thought that gravity pointed in the same direction everywhere. Today,
we think of that as a silly idea, but at the same time, most people today
(including most scientists) still think of spacetime as if it were a big box
with 3 space dimensions and 1 time dimension. So, like gravity for a flat
Earth, the single time dimension for the 'big box universe' points in one
direction, from the Big-Bang into the future. A lot of lip service is given
to the idea of "curved spacetime", but the simplistic 3+1 'box' remains the
dominant concept of what cosmic spacetime is like."
http://www.alwayson-network.com/comments.php?id=P10791_0_5_0_C
No paradox for time travellers
POSTED: 06.17.05 @09:51
THE laws of physics seem to permit time travel, and with it, paradoxical
situations such as the possibility that people could go back in time to
prevent their own birth. But it turns out that such paradoxes may be ruled
out by the weirdness inherent in laws of quantum physics.
Some solutions to the equations of Einstein's general theory of relativity
lead to situations in which space-time curves back on itself, theoretically
allowing travellers to loop back in time and meet younger versions of
themselves. Because such time travel sets up paradoxes, many researchers
suspect that some physical constraints must make time travel impossible.
Now, physicists Daniel Greenberger of the City University of New York and
Karl Svozil of the Vienna University of Technology in Austria have shown
that the most basic features of quantum theory may ensure that time
travellers could never alter the past, even if they are able to go back in
time.
The constraint arises from a quantum object's ability to behave like a wave.
Quantum objects split their existence into multiple component waves, each
following a distinct path through space-time. Ultimately, an object is
usually most likely to end up in places where its component waves recombine,
or "interfere", constructively, with the peaks and troughs of the waves
lined up, say. The object is unlikely to be in places where the components
interfere destructively, and cancel each other out.
Quantum theory allows time travel because nothing prevents the waves from
going back in time. When Greenberger and Svozil analysed what happens when
these component waves flow into the past, they found that the paradoxes
implied by Einstein's equations never arise. Waves that travel back in time
interfere destructively, thus preventing anything from happening differently
from that which has already taken place (www.arxiv.org/quant-ph/0506027).
"If you travel into the past quantum mechanically, you would only see those
alternatives consistent with the world you left behind you," says
Greenberger.
"This is a very nice idea," says physicist Avshalom Elitzur of the Weizmann
Institute in Rehovot, Israel, who also suggests that further work in the
area could help to clarify the nature of time itself.
Time is a very mysterious thing.
New Scientist
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