Article View: sci.physics.relativity
Article #725Re: EHRENFEST PARADOX AND OTHER IDIOCIES
From: john
Date: Sat, 06 Mar 2010 15:35
Date: Sat, 06 Mar 2010 15:35
200 lines
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13398 bytes
On Mar 6, 12:26 am, Pentcho Valev <pva...@yahoo.com> wrote: > Length contraction idiocies are a spectacular consequence of > Einstein's 1905 false light postulate but originally the time dilation > idiocy was developed: > > http://www.fourmilab.ch/etexts/einstein/specrel/www/ > ON THE ELECTRODYNAMICS OF MOVING BODIES By A. Einstein June 30, 1905: > "...light is always propagated in empty space with a definite velocity > c which is independent of the state of motion of the emitting > body.....From this there ensues the following peculiar consequence. If > at the points A and B of K there are stationary clocks which, viewed > in the stationary system, are synchronous; and if the clock at A is > moved with the velocity v along the line AB to B, then on its arrival > at B the two clocks no longer synchronize, but the clock moved from A > to B lags behind the other which has remained at B by tv^2/2c^2 (up to > magnitudes of fourth and higher order), t being the time occupied in > the journey from A to B. It is at once apparent that this result still > holds good if the clock moves from A to B in any polygonal line, and > also when the points A and B coincide. If we assume that the result > proved for a polygonal line is also valid for a continuously curved > line, we arrive at this result: If one of two synchronous clocks at A > is moved in a closed curve with constant velocity until it returns to > A, the journey lasting t seconds, then by the clock which has remained > at rest the travelled clock on its arrival at A will be tv^2/2c^2 > second slow." > > Einsteiniana's most pernicious hoax designed to vindicate the original > time dilation idiocy is the cosmic-ray muon hoax. It is based on > measuring the lifetime of muons "at rest". When cosmic-ray muons bump > into an obstacle so that their speed instantly changes from about > 300000km/s to zero, their forced and quick disintegration makes > Einsteinians sing "Divine Einstein" and go into convulsions. Why? > Simply because scientific rationality is so devastated that, when the > muon undergoes such a terrible crash, Einsteinians can safely declare > that in fact this muon is "at rest" and, being "at rest", > disintegrates more quickly than another muon which is not "at rest", > in perfect accordance with the predictions of Divine Albert's Divine > Theory: > > http://websci.smith.edu/~pdecowsk/muons.html > "The purpose of this experiment is to measure life time of muons > decaying at rest. Muons, produced in the atmoshere bombarded by high > energy cosmic radiation, are passing through the system of two > detectors located one above the other one. A coincidence of signals > from these two detectors (signals occuring in both detectors within > 100ns) marks a particle entering the muon telescope from above and > serves as a filter rejecting many noninteresting signals from > background radiation. Some particles, with appropriate energies, will > end their flight in the lower detector (proper amount of lead between > both detectors ensures that many of them will be muons). If a stopped > particle is muon, it will decay after some time producing electron. > The time interval between signals from the muon entering the lower > detector and the electron emerging after its decay is converted by a > time-to-amplitude converter into amplitude of signal fed to the CAMAC > analog-to-digital converter (ADC) controlled by the computer. The > spectrum of time intervals is displayed in the figure below. The > expected distribution should be exponential with the exponential time > constant being the average life time of muon. The full range of the > spectrum (about channel 2000) corresponds to the time interval of > about 25 microsecond. There are not many muons with such energies that > they will end their path exactly in the lower detector (usually they > will pass both detectors and will be stopped in somewhere in the > ground), so counting rate is rather low. To collect a reasonable > number of events, the experiment has to be run a number of days." > > Pentcho Valev wrote: > > For a century human rationality has been procrusteanized into > conformity with Einstein's idea that, for a non-rotating observer, the > periphery of a rotating disk is LONGER than the periphery of a non- > rotating disk: > > http://www.bartleby.com/173/23.html > Albert Einstein (18791955). Relativity: The Special and General > Theory. 1920. XXIII. Behaviour of Clocks and Measuring Rods on a > Rotating Body of Reference > > http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/general_rela... > John Norton: "If one has a circular disk at rest in some inertial > reference system in special relativity, the geometry of its surface is > Euclidean. That is quite obvious, but it will be useful to spell out > what that means in terms of the outcomes of measuring operations. If > the disk is ten feet in diameter, then it means that we can lay 10 > foot long rulers across a diameter. Euclidean geometry tells us that > the circumference is pi x 10 feet, which is about 31 feet. That means > that we can traverse the full circumference of the disk by laying 31 > rulers round the outer rim of the disk. What if we have a disk of the > same diameter of 10 feet but in rapid uniform rotation with respect to > the first disk? Things will go rather differently. Assume that this > rotating disk is covered with foot long rulers that move with it. > These rulers are just like the ones that were used to survey the non- > rotating disk. (That means that an observer moving with the rod on the > rotating disk would find it to be identical to one of the rulers used > to survey the non-rotating disk.) What will be the outcome of > surveying the geometry of this rotating disk with those rods? An > observer who is not rotating with the disk would judge all these > rulers to have shrunk in the direction of their motion. That means > that, according to this new observer, the surveying of the disk would > proceed differently. Ten rulers would still be needed to span the > diameter of the disk. Since the motion of the disk is perpendicular to > the rulers laid out along a diameter, the length of these rulers would > be unaffected by the rotation. That is not so for the rulers laid > along the circumference. They lie in the direction of rapid motion. As > a result, they shorten and more are needed to cover the full > circumference of the disk. Thus we measure the circumference of the > rotating disk to be greater than 31 feet, the Euclidean value. In > other words, we find that the geometry of the disk is not Euclidean. > The circumference of the disk is more than the Euclidean value of pi > times its diameter." > > In fact this is a second procrusteanization. Initially human > rationality is forced to believe (Paul Ehrenfest was a believer who > did not undergo the second procrusteanization) that, for a non- > rotating observer, the periphery of the rotating disk should be > SHORTER than the periphery of a non-rotating disk, as Einstein's > special relativity predicts: > > http://en.wikipedia.org/wiki/Ehrenfest_paradox > "The Ehrenfest paradox concerns the rotation of a "rigid" disc in the > theory of relativity. In its original formulation as presented by Paul > Ehrenfest 1909 in the Physikalische Zeitschrift, it discusses an > ideally rigid cylinder that is made to rotate about its axis of > symmetry. The radius R as seen in the laboratory frame is always > perpendicular to its motion and should therefore be equal to its value > R0 when stationary. However, the circumference (2*pi*R) should appear > Lorentz-contracted to a smaller value than at rest, by the usual > factor gamma. This leads to the contradiction that R=R0 and R0>R." > > Recently John Norton informed believers that two different disks > should be compared, one of them melted, set into rotation and then > solidified, as Einstein found it suitable to explain in a letter to a > friend (not elsewhere): > > http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/general_rela... > John Norton: "Note what was not said in this account. It did not say > that we take the first disk and set it into rotation. The reason is > that it is impossible in relativity theory to take a disk made out of > stiff material and set it into rotation. If one were to try to do > this, the disk would contract in the circumferential direction but not > in the radial direction. As a result, a disk made of stiff material > would break apart. If we want a rotating disk made of stiff material, > we need to create it already rotating. Once in a letter on the > subject, Einstein remarked that a way to get a disk of stiff material > into rotation is first to melt it, set the molten material into > rotation and then allow it harden. The rotating disk problem has > created a rather large and fruitless literature that suggests some > sort of paradox is at hand. Most of it derives from a failure to > recognize that a stiff disk cannot be set into uniform rotation > without destroying it." > > Now John Norton will be able to explain to believers how an 80m long > pole can be trapped inside a 40m long barn (the barn is melted and > then solidified?) and how a bug can be both dead and alive: > > http://math.ucr.edu/home/baez/physics/Relativity/SR/barn_pole.html > "These are the props. You own a barn, 40m long, with automatic doors > at either end, that can be opened and closed simultaneously by a > switch. You also have a pole, 80m long, which of course won't fit in > the barn. Now someone takes the pole and tries to run (at nearly the > speed of light) through the barn with the pole horizontal. Special > Relativity (SR) says that a moving object is contracted in the > direction of motion: this is called the Lorentz Contraction. So, if > the pole is set in motion lengthwise, then it will contract in the > reference frame of a stationary observer.....So, as the pole passes > through the barn, there is an instant when it is completely within the > barn. At that instant, you close both doors simultaneously, with your > switch. Of course, you open them again pretty quickly, but at least > momentarily you had the contracted pole shut up in your barn. The > runner emerges from the far door unscathed.....If the doors are kept > shut the rod will obviously smash into the barn door at one end. If > the door withstands this the leading end of the rod will come to rest > in the frame of reference of the stationary observer. There can be no > such thing as a rigid rod in relativity so the trailing end will not > stop immediately and the rod will be compressed beyond the amount it > was Lorentz contracted. If it does not explode under the strain and it > is sufficiently elastic it will come to rest and start to spring back > to its natural shape but since it is too big for the barn the other > end is now going to crash into the back door and the rod will be > trapped in a compressed state inside the barn." > > http://hyperphysics.phy-astr.gsu.edu/Hbase/Relativ/bugrivet.html > "The bug-rivet paradox is a variation on the twin paradox and is > similar to the pole-barn paradox.....The end of the rivet hits the > bottom of the hole before the head of the rivet hits the wall. So it > looks like the bug is squashed.....All this is nonsense from the bug's > point of view. The rivet head hits the wall when the rivet end is just > 0.35 cm down in the hole! The rivet doesn't get close to the > bug....The paradox is not resolved." > > Pentcho Valev > pva...@yahoo.com If you can close your barn doors instantaneously why can't the rod just zing through there instantaneously as well? Then you don't have to worry *how* long it is. john
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X-Google-Thread: 237b8ad48,97a819744ad9900c X-Google-Attributes: gid237b8ad48,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,ASCII-7-bit Path: arc1-ca.pugleaf.net!g2news1.google.com!postnews.google.com!q23g2000yqd.googlegroups.com!not-for-mail From: john <vegan16@accesscomm.ca> Newsgroups: sci.physics.relativity,sci.physics,fr.sci.physique,fr.sci.astrophysique Subject: Re: EHRENFEST PARADOX AND OTHER IDIOCIES Date: Sat, 6 Mar 2010 07:35:37 -0800 (PST) Organization: http://groups.google.com Lines: 200 Message-ID: <8bc953e4-3325-4ff0-adc1-883318592474@q23g2000yqd.googlegroups.com> References: <9d923082-ca10-4bc3-b5d5-31103ef7a32b@k17g2000yqb.googlegroups.com> <4b8f5ba5$0$27791$c3e8da3@news.astraweb.com> <e3595054-515d-42b0-885d-3c531c22d065@q21g2000yqm.googlegroups.com> <ce6f158e-1bbd-4204-bf2c-25f052e2191a@g11g2000yqe.googlegroups.com> NNTP-Posting-Host: 24.72.72.97 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 X-Trace: posting.google.com 1267889737 18990 127.0.0.1 (6 Mar 2010 15:35:37 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Sat, 6 Mar 2010 15:35:37 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: q23g2000yqd.googlegroups.com; posting-host=24.72.72.97; posting-account=azRwigkAAAA5Th7-XGkARzS64yAfV3nc User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax),gzip(gfe),gzip(gfe)