The Symmetric Twin Paradox
in [Relativity]
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From: kado on 17 Jun 2010 09:17 On Jun 16, 7:10 pm, colp <c...(a)solder.ath.cx> wrote: > snip > > Some solutions proposed by the relativists are: > > 1. Only consider one frame of reference, since SR fails when moving > between inertial frames. > 2. Ignore the paradox. Draw some timelines and say that everything is > O.K. > 3. Claim that the time dilation will be compensated for by > acceleration, even though there is no experimental support for time > compression arising from acceleration. > 4. Feet stamping and name calling. I am in general agreement with your assessment, but there are several things that must be addressed to enhance your position, and before this debate can be elevated to a logical and intellectual level. This paradox arises from the tenets of Einstein's Special Theory of Relativity of 1905. Einstein's Special Relativity addresses only uniform motion. Uniform motion implies (actually demands by definition) velocity, i.e., uniform (constant) speed in a straight line. So the resolution of the subject paradox cannot employ any notion acceleration, that by definition is a time rate change of velocity. Furthermore, the idea of acceleration was not introduced into Einstein's arsenal until he formulated the General Theory of Relativity, a decade after this paradox arose. In other words; any notion of acceleration cannot be applied to resolve this paradox. Moreover, the concept of uniform motion excludes any turning around. This in it's self creates another paradox, for it prevents the twins from ever coming together again. Einstein employed the idea that time contracts (not compresses, yes I realize this is nit picking, but such nit picking is important), always contracts. and only contracts when moving near the velocity (not speed) of light. The idea of time dilation was formulated in the mid 1960, about a decade after the death of Einstein, so the idea of time dilation also did not exist in Einstein's Special Relativity. Nevertheless, Special Relativity predicts that the traveling twin will age slower than the stay-on-Earth twin, while at the same time the stay-on-Earth twin will age slower than the traveling twin, because of the 'slower ticking clocks' with the frame of reference of each twin and Nature is time symmetrical. So even if the twins cannot ever come together, each will still be younger than the other at any instant (point in time) by the tenets of SR. Now don't bring up Einstein's Principle of the Relativity of Simultaneity, because Einstein really goofed on this by basing this foolish idea on when the phenomenon/event/ thing of interest is observed by the human observer, not when it occurred. The finite speed of light prevents the observation/detection of any 'thing' from being simultaneous with the occurrence, even if it occurred only a few meters away from the observer. It does not take a postulate to make the detection of a particular phenomenon from following the occurrence, and not being simultaneous with the occurrence, just common sense and a knowledge of physics. The concept of simultaneity is valid, and the idea of 'any point in time' is valid, especially if measured by like slow ticking clocks. So the twin paradox has not been resolved, even if all the silly relativists who think they understand SR come with all the BS posted on this thread. D.Y. Kadoshima
From: Tom Roberts on 17 Jun 2010 09:21 colp wrote: > On Jun 17, 1:25 pm, "Peter Webb" > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: >> Have you got a single experiment where SR predicts time dilation but it does >> not occur? > > The symmetric twin thought experiment (as described in the OP) is such > an experiment. No. It is a GEDANKEN, not an experiment. There are no actual measurements of this situation. > In the experiment SR predicts that the twins will both be younger than > each other when they return to Earth, which is of course impossible. This is just plain not true. You and that paper did not actually use SR. The comic book used does not describe the actual theory accurately enough to be useful. > Some solutions proposed by the relativists are: > [...] Those are not the real solution. The REAL solution is to actually use SR in the analysis of this gedanken. Tom Roberts
From: Daryl McCullough on 17 Jun 2010 10:14 colp says... >The classic twin paradox is asymmetric in that one twin remains on >Earth while the other leaves (i.e. only one of them accelerates and >deaccelerates). In the symmetric twin paradox both twins leave Earth, >setting out in opposite directions and returning to Earth at the same >time. The conventional explanation for the classic twin paradox is >since only one twin accelerates, the ages of the twins will be >different. In the symmetric case this argument cannot be applied. > >The paradox of the symmetric twins is that according to special >relativity (SR) each twin observes the other twin to age more slowly >both on the outgoing leg and the return leg, so SR paradoxically >predicts that each twin will be younger than >the other when they return to Earth. This is only a paradox to those incompetent at mathematics. Let's look at an analogous "paradox" in Euclidean geometry: You have two cities, Startville and Endville. Endville lies 1000 miles due west of Startville. There are two different routes to get from Startville to Endville: One route goes straight west for 1000 miles. The other route starts off traveling northwest then at the halfway point turns to travel southwest the rest of the way. From the point of view of a traveler following the straight path, the bent path looks longer: it travels away to the north for a while, and then it travels south for a while, and the total length is given by the Pythagorean theorem. From the point of view of a traveler following the bent path, it might seem that it is the *first* traveler who travels away to the *south* for the first half of the trip, and then travels to the *north* for the second half of the trip. So is it right for the second traveler to claim that the *other* traveler is following the bent path? Clearly no. In Euclidean geometry there is a "relativity" of directions. You pick any direction you like and call it your coordinate axis. There is nothing special about traveling west: you can let your axis travel to the northwest just as well. But there is *no* relativity when it comes to bent paths versus straight paths. All observers, regardless of how they set up their coordinate systems, can tell the difference between a straight path and a bent path. In SR, the analogy of "straight path" is "unaccelerated path" and the analogy of "bent path" is "accelerated path". Whether an observer is at rest or not is a matter of relativity, but whether an observer is accelerated or not is not relative: all observers agree about who it is that accelerates. -- Daryl McCullough Ithaca, NY
From: Peter Webb on 17 Jun 2010 10:27 "Koobee Wublee" <koobee.wublee(a)gmail.com> wrote in message news:b2e29c7c-b43a-4ce4-bd04-b8082581f7c9(a)k39g2000yqd.googlegroups.com... > On Jun 17, 12:10 am, "Peter Webb" wrote: >> "Koobee Wublee" <koobee.wub...(a)gmail.com> wrote: > >> > I have pointed out SR is a mathematical mistake of Poincare based on a >> > more robust Aether-centric Larmor's original transform. Thus, SR will >> > not correctly predict ALL experimental results. >> >> OK, which experimental results are not correctly predicted by SR ? > > All. <shrug> > No, you already said that time dilation and the twins paradox *was* correctly predicted by SR. Changing your story every post ... crank.
From: Peter Webb on 17 Jun 2010 10:30
"Koobee Wublee" <koobee.wublee(a)gmail.com> wrote in message news:3448c5c1-c107-4587-97fc-f468a38181a7(a)u26g2000yqu.googlegroups.com... > On Jun 17, 12:08 am, "Peter Webb" wrote: >> "Koobee Wublee" <koobee.wub...(a)gmail.com> wrote: > >> > Sorry, I meant "without" instead of "with". You know it is a late >> > night thing in my time zone. <shrug and yawn> >> >> So your position is that the GPS system does NOT take into account >> Relativistic effects? > > My position is that the GPS can function with or without the effects > of GR. Claiming GR as an application of the GPS is a total lie. > <shrug> > So why won't you answer my question? According to you, did the designers of the GPS consider Relativistic effects in the design of the GPS or not? |