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Testing Relativity
MGDruss writes "NASA are proposing an empirical measurement on the ISS which would test general relativity to a precision within the bounds of superstring (and other) theories to predict deviation." We mentioned the Cassini experiment last year.
Thus sayeth the article:
" LATOR would measure this deflection with a billion (109) times the precision of Eddington's experiment and 30,000 times the precision of the current record-holder: a serendipitous measurement using signals from the Cassini spacecraft on its way to explore Saturn."
AND
"The 0.02 as accuracy of LATOR is good enough to reveal deviations from Einstein's relativity predicted by the aspiring Theories of Everything, which range from roughly 0.5 to 35 as. Agreement with LATOR's measurements would be a major boost for any of these theories. But if no deviation from Einstein is found even by LATOR, most of the current contenders--along with their 11 dimensions, pixellated space, and inconstant constants--will suffer a fatal blow and "pass on" to that great dusty library stack in the sky."
So in other words they think that taking the measurements with 30,000 times the precision of the current measurements is enough to show if the current flock of string theories is plausable.
Every wrong attempt discarded is a step forward - T. Edison
You're probably referring to Occam's Razor. One way of expressing that principle is that if two theories completely and correctly explain a phenomenon, the simpler one is preferred. If you think the simplest explanation is always correct, you're liable to believe that me when I say "apples fall towards the Earth because that's where you plant them" or "the Earth was created 5000 years ago". There's more to truth than simplicity.
Gates' Law: Every 18 months, the speed of software halves.
Thank you for playing.
Scientists, _know_ that Quantum Mechanics and General Relativity are inconsistent with each other. It is believed that both are basically special, simplified cases of a more encompasing theory - and that neither can be 'built' on to agree with the other the way you suggest.
Note that that this doesn't mean that either theory is completely wrong within the boundaries of their frameworks. Just as it's perfectly acceptable to design an everyday building or car or airplane using Newton's law of gravity, NASA put those satellites into orbits using General Relativity and design the lasers on them using ordinary Quantum Mechanics.
M-Theory & Supersymmetry attempt to unify the efforts of those scientists studying string theory by making a self-consistent, simple, and elegant explanation for the why of everything. It attempts to resolve the basic, fundamental issues that quantum theory and general/special relativity have failed to answer. If this experiment happens, we may be able to determine whether we need to look for another contender, or whether the strange world of M-Theory is the path to follow. Hurrah!
Check The Official String Theory site if you're confused about all these concepts. When you've done that, you will have gained some answers, but will of course get even more questions. :-)
Beware: In C++, your friends can see your privates!
It's not so much that Einstein's relativity is wrong so much that it's incomplete. General relativity (and special relativity) have passed with flying colors every test we've ever put them to. Quantum field theory (the framework of particle physics) has done at least as well (in fact, it predicts some numbers in nature to more than 10 decimal places - far better than general relativity!). These theories are GOOD - they give the right answers. The problem is that both are incomplete in some way we don't quite understand. There are fundamental problems with making a quantum field theory of gravity - the two frameworks are very different, and they don't play well together. I wouldn't say that either is "wrong", they're just both incomplete. Both theories are probably nearly-perfect approximations to some sort of underlying framework (for example, string theory). Since neither theory can be the whole story, we expect that when we impose difficult enough tests on either one, they will begin to break down slightly - the world won't quite do what the theory seems to say. This is an excellent way to look for clues as to how these two frameworks fit together. You can look at this as an extension to relativity or a replacement for it.
Loop quantum gravity predicts that space comes in discrete lumps, the smallest of which is about a cubic Plank length, or 10^-99 cubic centimeter. Time proceeds in discrete ticks of about a Plank time, or 10^-43 second. The effects of this discrete structure (non-continuous) might be seen in experiments in the near future. One of these will be measuring radiation from distant gamma-ray bursts. These occur billions of light-years away and emit a huge amount of gamma rays within a short span. According to loop quantum gravity, each photon occupies a region of lines at each instant as it moves through the spin network that is space. The discrete nature of space causes higher-energy gamma rays to travel slightly faster than lower-energy ones. The difference is tiny, but its effect steadily accumulates during the rays' billion-year voyage. If a burst's gamma rays arrive at Earth at slightly different times according to their energy, that would be evidence for loop quantum gravity. The GLAST satellite, which is scheduled to be launched in 2006, will have the required sensitivity for the experiment. Recommend the cover story of this past January's Scientific American. Also an online pdf giving more technical details is available at http://arxiv.org/ftp/physics/papers/0108/0108026.p df
And thus I see that you have not studied this :]
I don't wish to pretend to understand all the issues, but I have suffered through enough physics that I believe myself to be capable of giving a simplified and reasonably correct overview (bearing in mind that I haven't had a physics class for a while now) --
Yes, we all like Relativity... on a large scale.
Just as we all like the Standard Model... at the very small scales.
The problem is that the two models are inconsistant. In fact, they outright contradict each other in what they say about the universe--space cannot be both smooth and discrete at the same time!
Thus, we need to harmonize the two, and this is why we have not one but several theories of quantum gravity. The problem has been that we simply do not have the observations to tell which theory is correct.
So some of the real issues here concern very fundamental issues of what matter is composed of and how it behaves and things of that nature. That's a bit more than, say, giving a better model of the spring by adding one more polynomial term to our approximation of Hooke's law.
TOS: the warp scale was in multiples of the speed of light. Warp 1 speed of light, warp 2 twice the speed of light.(Enterprise should follow this scale though I haven't paid that close of attention.)
NG: Warp scale got rewritten. warp 8 is roughly warp 14 on the old scale. warp 5 is warp 8 on the old scale. So when the NCC-1701-D hit warp 8 in episode 1, they traveled the same speed that ncc-1701 hit in the TOS.
Warp 10 in NG is equal to being all places in the universe at the same instance.
Now what kind of geeks are you.
i thought once I was found, but it was only a dream.
Althought I agree with most of your post I have to correct your last affirmation:
String theory is about all we have now.This is simply not true. String theory, been the most well known candidate for the Theory of Everything (ToE), is not the only one. If you wish to know about a different aproach to unifying Einstein's gravity and quantum field theory you can check Quantum Gravity
Jokes get ruined when you splain them. But I won't let that stop me. Woman says the world is supported by a turtle. Physicist says "what's holding up the turtle?" Woman says another turtle. Physicist asks "and what's holding up that turtle?" And she says "I see. You're very clever. But you can't fool me, it's turtles all the way down!"
or something like that.
--
Greg Egan's latest novel, Schild's Ladder is highly recommended for anyone interested in seeing what might go wrong if you test the fermament of reality a little too much. Seismic-shocks-in-the-aether is a pretty impressive feat for the author! A lot more is packed into the 327 pages than is taken in at first reading, and, frankly, it is not for anyone who didn't enjoy True Names by Vernor Vinge. Though the testing of physical theories to their theoretical limits is the very basis of Schild's Ladder, for a proper build up to this novel, his other novels and short story collections are an excellent preparation - probably best read in order, except with Teranesia set aside for the 'come down period' after everything else has been read (perhaps a few times). Schild's ladder is very much a synthesis of all the journey's Egan's stories have taken, and an exploration of the ultimate perils and pitfalls of unit testing the universe!
p.s. if you only read one Greg Egan, try Axiomatic; reading all 18 short stories in one sitting is like eating an entire box of chocolates at once -- your mind feels sickly sweet and luciously overloaded with Egan's amazing ideas. Here's the list of titles to whet the appetite:
Oliver's Law: Experience is something you don't get until just after you need it.