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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.
What ever happened to the concept that the simplest explaination is probably the best?
that only works in movies starring jodie foster.
Sig (appended to the end of comments you post, 120 chars)
That is what they are looking for. A simpler explaination then the Standard Theory :) Have you sutdied that theory in depth? It is enough to make your head explode. At least with the 11-dimensional theories the math makes some sense :)
That is often true but... what is that simplest solution? People compare string/M-Theory to how the geocentric view of the universe was justified. People had supposed a heliocentric view of the world, but people believed that there were epicycles and such instead of that.
Where is the simpler solution here? General Relativity and Quantum Mechanics are NOT compatible in many cases (for example extremely small but extremely heavy objects like black holes cause things like infinite probabilities which does NOT make sense). We have no simpler solution. String theory is about all we have now.
Humans are needed when things go wrong
sure when everything goes as planned we don't
need any human intevention, but since men first looked up to the sky the fact remains big projects always have something go wrong.
The robots are not able to improvise. Have you looked at the mars score card which was published on slashdot a while back? unmanned missions tend to fail.
To the best of my knowledge each and every manned mission to space had something go wrong, and a human being on board help fix it. You can't tell your robot to perform an unplanned spacewalk because something went wrong. and you just might want to do just that.
In addition to this, some of the tests we are intrested in doing involve testing how humans can live in space how we react to a micro-gravity enviorment these obviously require sending men and women into space.
Yes there are risks involved but there are many dangerous proffesions out there, cleanning windows on high-rise buildings is a dangerous job, but we still do it, and it gives back to humanity much less then space exploration.
Me.
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
The dude who invented this principle phrased it this way (translated from the Latin): "Entities should not be multiplied more than necessary." But what entities are "necessary"? To Ockham, God was a necessary entity, yet you hear Ockham's Razor used to deny the existence of God.
Bottom line: OR is a highly subjective tool that should be applied with great care. And even then, it can mislead you -- the simplest plausible theory can still be wrong, due to evidence you haven't seen. OR is a strategy for coming up with good theories, not a law of nature!
Slashdot logic.
:)
Testing mathematical theories by means of slightly twisted democracy.
--= Isn't it surprising how badly I spell ?
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.
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
It's turtles all the way down, man.
My user number is prime. Is yours?
Warp 10 is impossible.
Only be definition as given in the fantasy.
Since everything in ST is a fantasy and has no basis in the physical world.
If the ST writers wanted to write that infinite speed travel was possible, they could and it would be no more fantastic than what you have already.
Given the physical world. Travel at the speed of light for an object is essentially infinite so there is no basis between the physical world and the ST world to distinguish between what is possible and impossible. Travel greater than the speed of light is not "infinite" but it is not intuitive in the way it is portrayed on ST.
Get a life.
The warp scale represents speeds exponentially closer to infinity. According to the scale, 10 is the asymptote representing infinite speed. The single episode of Trek (Voy: Threshold) in which this feat is accomplished is often considered not canon by fans because the writer was a moron.
Bah. This is a bunch of crap. In the last episode of STTNG there is reference to Warp 13 (in the future Enterprise). This future time was only about 25-30 years from the TNG "present" which means it was in the same time period as the Voyager episodes.
The scale has been used very loosely in the movies.
What does this all mean?
It means that while the ST franchise has produced some enjoyable dramas, it is lame and sad to try to take anything in the ST world and rationalize it or explain it.
You ST nerds sicken me.
"Humans are needed when things go wrong"
Humans are resourceful and adaptable, but we also have fragile bodies that need lots of facilities and supplies to survive in space. For the enourmous price of providing life support for a manned mission, you could duplicate an unmanned mission many times over. There are many good reasons for putting humans in space, but doing science experiments better than robots is not one of them.
Actually, Occam's Razor is not "the simpler theory is usually the right one," it is "create no unnecessary hypotheses." That may sound the same, but it's not. For example, many religions posit a soul or other non-corporeal entity that persists after the death of the body. Modern science doesn't claim to have a firm grip on sentience and awareness, but it appears to be a highly complex system of nervous reactions. (I imagine most of the Slashdot crowd knows that a complex system of conditionals, like a computer, can seem very life-like.) The point is, the mechanistic understanding of awareness explains it without recourse to a soul. Consider the natural chemicals in our bodies that contribute to mood, or artificial chemicals (like drugs or alcohol) that can alter one's personality, or even cases of trauma to the head, and "soul" is left as nothing but a non-explanation -- an unnecessary hypothesis.
p ri nciples.asp
Another non-explanation is the idea that "warped space" explains gravity. All it does is push the explanation back one step from "what is gravity?" to "why do masses warp space?" So which is the correct theory? I don't think there is one, and our ideas or "understanding" of the universe will continue to evolve with everything else around us. The Pythagoreans believed that math was truth, and that reality was merely an imperfect shadow of the real world hidden beyond the veil of our senses. Well, this isn't the Matrix, an no amount of passion for "perfect" answers (like "elegant" equations or crystal spheres in the sky) will make it so.
You want an alternative theory? Give Tom Van Flandern's Meta Model a try. It may be no better than the orthodoxy of Einsteinian Relativity and quantum mechanics, but at least it won't resort to mathematical trickery and the comforting reassurance of what we'd LIKE to believe. A good introductory article may be found at:
http://metaresearch.org/cosmology/physicshasits