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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.
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Relativity has already been put to the test. I mean, if time wasn't flexible, how else would Arthur Dent be able to witness the end of the universe every evening at Milliways?
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
This is probably going to be marked flamebait or offtopic but this experiment could have been unmanned. If anyone claims this is a good reason to have a manned space station, I defy them to specify how having humans aboard is needed in this case.
Now geology, that's a different story.
Blaze a trail to the New World
The article implies that Einstein's relativity is incorrect, in the opinions of most scientists. I'm no physicist, but I would say that most scientists are trying to build onto Einstein's relativity and show that it agrees with Quantum Mechanics: Therefore, they think it is correct.
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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.
Is it no surprise then that the EU wants to cancel the ISS? Even with the faults the station has, it's still the best way to conduct low gravity experiments. It's intolerable that the Europeans want it over and done with.
If you read the article, you will see this is not a "low gravity experiment". They are placing an interferometer aboard the ISS, above atmospheric distortion. An unmanned rocket would probably do the job more cheaply. But, as long as governemnts are already wasting billions of dollars sending people up to the ISS, we might as well give the interferometer to them and tell them to turn it on, thus sparing a separate rocket launch.
This still doesn't mean the ISS is anything other than a giant orbiting multibillion dollar turkey.
You're reffering to Occam's Razor. "One should not increase, beyond what is necessary, the number of entities required to explain anything". But the point is that we CANT sufficiently explain it. Relativity and Quantum Theory are in conflict.
But my question is, if this has been tested by the Cassini test and others and the result has been proven, why are we bothering to do it again?
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As simple as possible...but no simpler!
It has to still fit the inconvenient experimental facts.
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.
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!
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?
An argument in 1900:
Newton's gravity was tested and proven. So why test for anything else? So what if mercury's orbit is a little odd. Gravity works.
I still have more fans than freaks. WTF is wrong with you people?
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.
Warp 10 is impossible
Of course it is. Go fast enough and eventually it would be possible to go back in time and re-write bad plotlines. Or be able to see Slashdot articles before they are posted.
Wait...
String theory predicts deviations from General Relativity at very high energies and very small distances. I would be very surprised to read of a string theory model -- or class of models -- that predicted solar system scale effects in their basic framework. The importance of string theory effects is suppressed by a huge factor depending on the local energy density in the experiment you are testing. The string energy scale is so far away that it would be a great coincidence if it just barely showed up in the solar system but did not, e.g. rip it all apart. Sort of like crashing your car through the window of a bookstore and having the resultant mess just precisely turn one page of one book.
This is not a bad experiment to do, because there are theories -- mostly cosmological ones -- that predict differences in gravity that would show up in this theory, but they are definitely non-standard modifications to particular theories. I have done work on these kinds of theories, and let me tell you, it is a certain amount of work to actually generate theories that even care about such low energies and large distances that you can test them even with an "ultimate" measurement.
I am disappointed by the rather slipshod understanding of science and the issues that this article represents. "Evicting Einstein" is a sensationalistic headline, and it's just not true -- as anyone will tell you, Newton was not "impeached." A much better angle that this article could have taken was that of exploration of gravity, as opposed to "putting the chalk scribblers in place."
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Oh wait, I've confused Science with religion, again.
This issue is a bit more complicated than you think.
What you're talking about are exceptions which use different warp scales, entirely different methods of traveling through space, supernatural beings, or in some cases alternate realities created by supernatural beings. All of which is perfectly explained and believable.
So wait, the Enterprise being able to reach a velocity defined as an asymptote is okay and believable when an alien entity does it? That is the dumbest fanboy excuse I've ever heard.
The only one that isn't is Voy: Threshold. It's the biggest stain on Trek since TOS: Miri.
No, dude, Threshold isn't a universally reviled episode because the science doesn't make sense (if that were the case, there'd be very few good episodes of Star Trek) or because it broke continuity (something Star Trek has never been big on). It's a bad episode because traveling at infinite speed made Paris and Janeway devolve into salamanders.
Les Miserables Volume 1 now up with my reading of
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
Nope, it will be phlogiston theory all over, not epicycles.
Phlogiston was covered in a real theory, IOW phlogiston explained (wrongly) how the burning process occurs and why some stuff burns and other stuff doesn't. Epicycles OTOH where never a theory, epicycles didn't try explain to the crazy motions of geocentric orbits but only to accurately describe them.
Even Ptolemy himself knew that epicycles where fundamentally wrong for two reasons: 1) the earth is not exactly at the center of the planets, suns and moons orbits (the center of the orbit is the halfway point between the earth and the equant); and 2) a planet on an epicycle would crash into it's own "heavenly" or "crystalline" sphere on which it was supposed to be mounted. IOW Ptolemy knew that epicycles wheren't compatible with Aristotle's theory nor with Pythagoras'; but he still affirmed that those theories were correct.