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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.
Which theory do you think will win? Seriouslly, this is really exciting. As an avid Physics buff I am really looking forward to the outcome.
http://jamesphogan.com/bb/archives/relativity.shtm l#081797
SUGGESTED NASA EXPERIMENT Posted on August 17, 1997 contents
RELATIVITY EXPERIMENT
A couple of weeks ago, a friend of mine at NASA invited me to submit any suggestions I might have for possible experiments to be carried out by future mission, involving advance physics. Since a few people have been in touch regarding the skepticism I've expressed in the past about the basis of Relativity, I thought my response might be of general interest, and so reproduce it below.
[To give credit where due, a virtually identical proposal was submitted to NASA some years ago by the late engineer and metallurgical consultant, Carl Zapffe. Nothing came of it. If anyone thinks I'm way off the mark, I'd be happy to hear from them.]
Dear Les,
Herewith the following, offered in response to your invitation.
INTERFEROMETRY BEYOND THE TERRESTRIAL MAGNETOPAUSE
The Einstein Special Relativity Theory (SRT), we all "know," forms one of the cornerstones of modern physics. Its predictions are utilized on a routine basis, and it has withstood every experimental test.
These predictions boil down, essentially, to applications of the principles of (i) mass-energy equivalence (E=mc*2), (ii) mass dependence on velocity, and (iii) time dilation. Experiments verifying these relationships have been performed with increasing precision in the course of the past century. These are the proofs that the textbooks cite in support of SRT, and which its defenders point to when questions are raised concerning Relativity basics.
But it turns out that _all_ of them can be derived by purely classical procedures, independently of any Relativistic considerations. They don't say anything unique about SRT at all. (i) follows from the principle of conservation of momentum and Maxwell's equations. Carl Zapffe gives three derivations in his book "A Reminder on E+mc*2," with numerous references that show how it was implicit in the physics known at the end of the nineteenth century. Regarding (ii), Petr Beckmann, in his "Einstein Plus Two" (1987), shows how the increase of "mass" with velocity arises as a manifestation of the electrical inertia of charges moving through fields--analogous to aerodynamic drag.
Essentially, these are effects arising from the energy differences of relatively moving systems. The question they lead to is whether the results observed regarding (iii) (e.g. the extended lives of cosmic-ray muons) are in fact confirmation of "time" being dilated, as per SRT, or result from the physical slowing-down of clocklike processes in motion through a field. The only way to test this empirically would be to sit on an incoming muon and observe whether the laboratory clocks (at rest in the field) also slow down (as the observer-referred SRT holds) or speed up (as a field-referred theory would predict). This has never been done. (A whole literature exists on all this, but I don't think that here would be the place to elaborate further.)
So, the standard proofs turn out not to be proofs at all. All that's left, then, is the interpretation of the 1881 Michelson-Morley attempt to measure an "ether wind," and its many variations performed since.
The null results returned by these experiments have two possible interpretations: (1) There is no ether; (2) the ether local to the Earth is entrained in its orbit around the Sun. (1), of course, is the orthodox line. The constancy of the speed of light for all observers is a _postulate_ that follows from accepting this interpretation. Contrary to common belief, it has never been verified experimentally. (The claimed verifications all involve round-trip measurements that average out the c+/-v velocities that arise in field-referred theories.) Having thus conferred constancy on a velocity, it then becomes necessary to distort space and time in order to preserve it. This, in effect, is what the transformation equations of SRT do.
Treating th
The "Evicting Einstein" title of the article is misleading. IMHO, the Theory of Relativity cannot be proven incorrect...it can only be proven *incomplete*. Far too much evidence/data exists to prove the interaction of light and gravity and space-time as predicted by the GTR.
Even if the Quantum theory is proven correct, the Theory of Relativity will live on as an effect of the quantum theory - since it explains the effects of Quantum behavior on the macro-level...something that Quantum physics is not very good at. Just like the General Theory of Relativity proved that Newtonian physics was not incorrect, just incomplete, the Quantum theory will prove to be a superset of the GTR.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
Warp 10 is impossible. 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.
It should be noted that the man who wrote that episode never went on to write for Trek ever again. And it should also be noted that other episodes featuring warp factors of two digits were using a different scale.
You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
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.
The goal is the simplest explanation that explains the obervations. When the observations get wierd, so do the explanations. And when things get very small, they get very wierd indeed.
Warp 10 is impossible. 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
Single episode? I know they retconned all the TOS episodes where aliens modified the Enterprise to go faster than warp 10, but there's still TNG's "Where No Man Has Gone Before," in which the Enterprise-D exceded warp 10, and the future scenes in "All Good Things" where warp 10+ was no big deal.
Les Miserables Volume 1 now up with my reading of
Slight sidebar perhaps...
In the article it says that GPS would not be possible without the use of Relativity Theory.
Why is this? Is it due to time dilation effects at the speed of the satellites?
Or something else I'm not thinking of?
Something that always bothered me about "dimension" counts - a rule in programming design is the "0,1,N" rule - don't allow something, allow it once, or allow it as many times as the user wants. Odd upper limits are annoying and stupid. So my bet is that the real theory is truly infinite-dimensional (yeah yeah hilbert spaces, but I mean the real "ultimate reality" in which our perceived 3+1D world is embedded..)
Please, take some time and read this paper. It was the most facinating paper I have read in years. It explains many phenomina using classical mechanics.
e wt onphysics.html
http://www.newtonphysics.on.ca/Newton-physics/N
Jamey Kirby
if you are testing GR in the framework of GR, then you are not learning anything new.
I am the Alpha and the Omega-3
Actually, there are science-based satellites launched on a regular basis. I attended a meeting of a NASA hydrology working group this weekend in which we discussed a bunch of satellite mssions including GRACE, Hydros, Aquarius, ICEsat, CryoSat, and others that have either gone up in the last ~2 years or are going up soon. And those are just missions with relevance to hydrology. In more general terrestrial remote sensing, both Aqua and Terra are big platforms that have gone up in the last few years. So in actuality, there are quite a lot of satellite missions being launched all the time. Something like this, with an important purpose relevant to a lot of scientists, probably stands a pretty good chance. I don't actually know how much it would cost, but I would bet on the order of a few hundred million dollars, if its similar in cost to the other platforms mentioned.
(1) The simple practical reason that a simpler theory is often more practical.
(2) If the theory becomes drastically more simple, at the cost of a little accuracy, it may be pointing to a deeper insight into the problem. For example Ptolemaic astronomy could be made to fit planetary orbits as accurately as you like by adding enough epicycles. Initially Keplerian theory appeared to be less accurate, not more. Yet Keplerian theory was ultimately the way to go. In fact, this situation is common in everyday work. It's easy to fit a curve accurately to any amount of data by adding lots of terms but it's often the simple fitted expression that actually does a better job of interpolating correctly between the data points.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
None of the explanations we have seem all that simple. Guth's inflationary model requires that, if certain factors are truely random, there are an infinite number of non-observable parellel universes. Hawking's recent work postulates both a negative and an imaginary axis for time, neither of which we can observe. Half the black hole theorists (approximately), suggest that an expansionary process turns the inside of each black hole into a new universe, which again we can never observe.
Quantum Mechanics either postulates a pseudo-infinity of branching universes (which is a second kind of infinite set, unrelated to the inflationary model set, and which, again, we can never observe), or says that not only does the tree not make a noise if there's no one around to hear it, but the tree doesn't fall at all, rather it transitions outside of space-time from standing when you observed it earlier to already fallen when you observe it again.
Some forms of inflationary theory imply the universe is big enough to have yet another kind of pseudo-infinity associated, simply because if it is billions of times as big on each axis as the part we can observe, patterns as complex as our own galaxy or the whole observable universe must repeat in detail, many, many times. Some of the 'brane' theories add a second kind of true infinity, so if these are right, we're trying to describe something with two separate kinds of real infinity and two sets of enormously large numbers (i.e. 10 to the 10 to the 10 to the 10 to the 81st power) needed just to describe its dimensionality, and all occuring from unrelated causes.
Assuming some of the "random" factors are not really random in different cases may make the results simpler, but a "non-random cause", existing outside nature (we might even say superior to nature, or supernatural for short), is predicting something we can't observe either, and that something starts sounding like the price of simplicity is saying "God did it, and who are we to ask questions?"
God is not a scientific hypothesis, not in the sense that science says there is no God, but in the sense that if God exists, 'he' will not allow us to perform repeated experiments and get reproduceable results from them, and irreproducable results aren't science. So much for simple.
Who is John Cabal?
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.
I am an interested layman, so the following may not be entirely accurate. But it may give you an idea.
It is not entirely true that such small-scale effects can only appear on a small scale. If space is discrete, it can also affect the travel of light. Imagine a grid with 1 cm or 1 inch on a side. Now, draw a line from (0, 0) to (10, 1.1).
If space is discrete, the beam can't do that and it will do something else. Since space is most likely not a perfect grid, I don't feel like I can say exactly what it would do, but it would be impossible for the ray to be at (10,1.1) and as a result it would affect the direction it could travel.
If space is continuous, the ray can indeed be at (10, 1.1) and the ray will behave differently.
I have seen people talking about using light from extremely distant galaxies to try to detect this effect, seeing if the light shows "quantization" in certain parameters (not the traditional quantization, but seeing that only certain directions exist in the light), but since we can't source or control the light, my impression was we could not get enough info for it to matter.
The article did not say this is what they are trying to do, but based on my understanding it is plausible and would account for the article. Since we can source the light and even guarentee phase consistency (allowing us to use interference), we can make up for only having a handful of AU instead of billions of lightyears by controlling the light perfectly.
Even if this is not what they are doing, I hope it shows you a way that even ultra-microscopic effects can be magnified enough to be detected in this experiment.
I'm quite impressed; this is straightforward in a way, but audacious and excellent thinking out of the box.
I'm waiting for the creation of mini-holes at the new Large Hadron Super Collider over in Europe around 2006-7. If that type of energy could be harnessed, who needs "Mr. Fusion", gasoline, H2, or any other energy substance? Just take unbiodegradible trash and run a city on 1 ton of it.
;-) (and a 1100 lbs heavier black hole)
-- As a note, one gram of pure U235, if converted to pure energy (100% efficency, e=MCC) would power New York city for 1 day. A black hole with top spin is theorised that you could extract 45% of it's mass as inertial energy. 1 ton of crap means you have 900 Lbs of "energy".
Past that, if he was a fraud... he was a damned clever one at that.
The simple theory of everything must eventually fit the constraint of not having a design which necessarily entails a designer but instead having a design consisting merely of mappings from the entirety of mathematics, metamathematics, and the much larger realm of mathematical possibility - this last entity being necessarily logically incoherent.
In metamathematics, about the only a priori landmark I know of is Godel's proof. It separates the finite and logically unambiguous field of geometry from general mathematics. My favorite thought is to map this landmark onto the boundary of classical, geometric, physics with the distinctly different field of quanta. The need, proved by Godel, for an unlimited number of axioms in general mathematics then maps rather nicely onto the uncertainty principle in nonclassical physics. And, since general mathematics does not map onto geometry, it follows that quantum mechanics does not map onto general relativity. Like ordinary categorical propositions in self referential logic, quanta can not be linked to particular locations.
String theory is so ad hoc and unprincipled that it can not compete with these considerations. String theorists do not take very well after the examples of Spinoza and Einstein.
The other a priori landmark in mathematics that I know about is the distinction between coherent mathematics and logically incoherent mathematical possibility. The mapping of the two can not be complete, since one is innumerably larger than the other.
These three levels have a particular way of mapping onto each other and within themselves, and then of mapping onto physics and metaphysics, I think.
Geometry maps exactly and nonmetaphorically onto classical physics - properly defined rather than conventionally defined; this is the Einstein-Davis hypothesis emphatically ratified. The metaphysical notion of first cause is then contained entirely inside of general relativity, since this theory itself mandates causality.
Just as geometry can only be a partial map or symbolic transform of general mathematics, the classical universe in its geometric character can only be an epiphenomenal or partial translation of quantum mechanics. But, both of these translations are logically coherent, if partial. So, the metaphysical concept of the logical ground is mapped onto the logical substructure which is provided by quantum mechanics to classical general relativity.
Mathematical possibility consists not merely of all mathematical statements, but of all translations between them, and of all transforms between translations and between translations and statements, and so on. This enormous entity maps to the metaphysical concept of the ground of being. It is all but entirely incoherent.
Quantum mechanics is then a very partial relation or symbolic transform of mathematical possibility - actually ever possible transform which meets the criteria of approaching logical coherence. And, it seems that all features of classical physics, in particular time, are needed in order to attain a maximal logical coherence in quantum mechanics.
So, this is a theory containing a maximum of complexity. But, it is simple in being a priori as much as possible.
--
Michael J. Burns http://home.mindspring.com/~mburns9/
Michael J. Burns