The Symmetric Twin Paradox
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From: Cosmik de Bris on 21 Jun 2010 21:58 On 22/06/10 12:06 , Inertial wrote: > "Cosmik de Bris" <cosmik.debris(a)elec.canterbury.ac.nz> wrote in message > news:R5TTn.40738$7d5.40128(a)newsfe17.iad... >> On 22/06/10 05:55 , colp wrote: >>> On Jun 21, 10:56 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >>> wrote: >>>> colp says... >>>> >>>>> O.K. What remains from my previous post is the question of how you get >>>> >from the original premises of SR to a determination on when you should >>>>> apply the transformation for a single clock, and when you should apply >>>>> the transformation for the time coordinate in the case of the twins. >>>> >>>> It depends on the question. If you have a clock moving around on some >>>> path from event E1 to event E2, and you want to know the elapsed time >>>> on that clock, then you compute it like this: >>>> >>>> Elapsed time on the clock >>>> = Integral from t1 to t2 of square-root(1-(v/c)^2) dt >>>> >>>> where t1 is the time of E1, t2 is the time of t2, and >>>> where v is the velocity of the clock at time t. You can >>>> use any inertial coordinate system that is convenient >>>> to measure t1, t2 and v, and you'll get the same answer. >>>> >>>> The other kind of question is this: How old is one twin when the >>>> other twin's clock shows 200 seconds? >>>> >>>> That question is *not* a question about elapsed times on a single >>>> clock. You have to *also* answer questions about simultaneity. >>>> To answer the question, you need to know which events involving one >>>> twin are simultaneous with which events involving the other twin. >>>> To know whether two events are simultaneous, you have to pick >>>> a coordinate system. >>> >>> Thank you for your response. I'll repost it on sci.physics.relativity >>> in Uncle Ben's thread >>> >>> "colp, why did AE use the word "relativity"?" >>> >>> in order to stop crossposting to nz.general (nz.general members have >>> pretty much abandoned the thread and it's not that relevant to most of >>> them) >> >> Well, I was the one who asked you to post on nz.general and you >> haven't responded to my posts. > > Why would you ask him to post his lack=of=understanding of physics on a > general nz newsgroup anyway ??? > > Well that's a good point, I was just trying to get a conversation going on something other than politics. :)
From: Inertial on 21 Jun 2010 22:33 "Cosmik de Bris" <cosmik.debris(a)elec.canterbury.ac.nz> wrote in message news:YMUTn.2380$Yo5.754(a)newsfe01.iad... > On 22/06/10 12:06 , Inertial wrote: >> "Cosmik de Bris" <cosmik.debris(a)elec.canterbury.ac.nz> wrote in message >> news:R5TTn.40738$7d5.40128(a)newsfe17.iad... >>> On 22/06/10 05:55 , colp wrote: >>>> On Jun 21, 10:56 pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >>>> wrote: >>>>> colp says... >>>>> >>>>>> O.K. What remains from my previous post is the question of how you >>>>>> get >>>>> >from the original premises of SR to a determination on when you >>>>> >should >>>>>> apply the transformation for a single clock, and when you should >>>>>> apply >>>>>> the transformation for the time coordinate in the case of the twins. >>>>> >>>>> It depends on the question. If you have a clock moving around on some >>>>> path from event E1 to event E2, and you want to know the elapsed time >>>>> on that clock, then you compute it like this: >>>>> >>>>> Elapsed time on the clock >>>>> = Integral from t1 to t2 of square-root(1-(v/c)^2) dt >>>>> >>>>> where t1 is the time of E1, t2 is the time of t2, and >>>>> where v is the velocity of the clock at time t. You can >>>>> use any inertial coordinate system that is convenient >>>>> to measure t1, t2 and v, and you'll get the same answer. >>>>> >>>>> The other kind of question is this: How old is one twin when the >>>>> other twin's clock shows 200 seconds? >>>>> >>>>> That question is *not* a question about elapsed times on a single >>>>> clock. You have to *also* answer questions about simultaneity. >>>>> To answer the question, you need to know which events involving one >>>>> twin are simultaneous with which events involving the other twin. >>>>> To know whether two events are simultaneous, you have to pick >>>>> a coordinate system. >>>> >>>> Thank you for your response. I'll repost it on sci.physics.relativity >>>> in Uncle Ben's thread >>>> >>>> "colp, why did AE use the word "relativity"?" >>>> >>>> in order to stop crossposting to nz.general (nz.general members have >>>> pretty much abandoned the thread and it's not that relevant to most of >>>> them) >>> >>> Well, I was the one who asked you to post on nz.general and you >>> haven't responded to my posts. >> >> Why would you ask him to post his lack=of=understanding of physics on a >> general nz newsgroup anyway ??? >> >> > > Well that's a good point, I was just trying to get a conversation going on > something other than politics. :) Fairynuff :):) ... at least with physics one is pretty much either right or wrong .. whereas politics is mostly opinions (which make for far more interesting and heated discussions, but no definite answers)
From: kado on 22 Jun 2010 05:39 On Jun 21, 4:04 am, "sci.math" <marty.musa...(a)gmail.com> wrote: > On Jun 21, 2:43 am, "k...(a)nventure.com" <k...(a)nventure.com> wrote: > > > > > On Jun 19, 6:22 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > > > > k...(a)nventure.com wrote: > > > > On Jun 18, 8:45 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > > > >>> Nevertheless, what you do not seem to realize and be able to > > > >>> accept is that the whole of Einstein's SR and GR are based > > > >>> on gedankens, and not a bit of these are based on empirical > > > >>> experimentation! > > > >> This is WILDLY untrue. There are HUNDREDS of experiments that confirm various > > > >> predictions of SR, and directly refute Newtonian mechanics. > > > > > I hope you understand that both SR and GR were formulated before > > > > these experiments were conducted. > > > > That does not matter. This is PHYSICS, not history. And Einstein did know of > > > several experiments that were inconsistent with the then-current notions of aether. > > > Whether Einstein did or did not know that there were experiments > > that were inconsistant with the then prevailing ideas of ether are > > true or not is not important, because then-current notions of ether > > are of no relevance (i.e., do not apply) to the paradox under > > discussion. > > > snip > > > > Writings in ancient texts are IRRELEVANT. What matters in physics is the > > > correspondence between theory and experiment. Ancient texts have been boiled > > > down to the essential theory underlying them; this is usually necessary in > > > science. Science is the formulation of models of nature, and refining and > > > improving them via experiments; it is NOT the study of ancient texts. > > > What is important is that while physics is not about history, the > > historical progression of what is considered the truth is crucial in > > the understanding of the Natural universe and the sciences. > > > 1. The first step to knowledge and the truths is understanding the > > meanings of the words. > > 2. The truths you can put in words and pictures (and numbers) are > > not the whole truths. > > 3. To find the truths, you must first verify the ones you have. > > > Furthermore, the are: > > > 1 Conditional truths, that are true under some conditions and > > situations, but not so under other conditions and situations. > > 2. Relative truths that are true from one point of view, but untrue > > from another. > > 3. Generalized truths that are statistically (mathematically) more > > probable to be true than not, and/or 'educated guess'. > > 4. The fundamental truths, that are the underlying truths upon > > which all the other truths are based, and that are true all the > > time, underr all conditions, regardless of the point of view. > > > So a little language (meaning of the words), history and > > philosophy lesson seems to be in order. > > > Science is the pursuit of knowledge and the truths, as > > distinguished from ignorance or misunderstandings. > > > Physics is that branch of science that pursues the true > > knowledge and understandings of the true nature and > > workings of the Natural universe. > > > In other words; you have mistaken the effect with the cause, > > for theorems and empirical experiments are the means that > > scientists employ to reach the goals of understanding the > > true nature and workings of the universe. > > > Furthermore. in the sphere of intellectual endeavors, there is > > a category that sits above the sciences. PHILOSOPHY. > > > Philosophy is the pursuit of wisdom, reality, and the ultimate > > truths. > > Philosophy separates into the sciences, metaphysics, and > > theology > > The sciences (all the sciences were bunched into the category > > of physics in the old days) deal with the natural. > > Metaphysics address the unnatural. > > Theology pertains to the super natural. > > > Therefore the validity of all theories, hypotheses, principles, > > laws, maxims, etc., and even the notion of a truth is dictated > > by the verity of the philosophy upon which these ideas are > > based. > > > The ancient Greeks formulated many philosophies, e.g., the > > Philosophies of Stoicism, Realism, Idealism, etc. It was during > > these very early days, long before even Aristotle, that the > > Philosophy of Idealism became the dominate and guiding > > maxim to follow and obey for almost all human intellectual > > endeavors. The fundamental tenet of this philosophy is: > > > Since every phenomenon, object, entity, body, thing, EVENT, > > occurrence, etc., exists only in the mind of man (i.e., humans), > > and as the universe is the sum of its parts, the universe does > > not exist except as the perception of human (i.e., my, and/or > > me myself and I, the human observer's, the human looker's, > > the human knower's, etc.,) understanding. > > > So Einstein always incorporated a human observer in all his > > thoughts, gedankens, ideas, etc., and theories. > > > However, there is one very important point missed by all the > > ancient and modern theorists, > > > The Philosophy of Idealism that all the notable theorist (e.g., > > Aristotle, Leibniz, Descartes, Einstein and even Hawking and > > Thorne, with the exception of Galileo Galilei and Issac > > Newton) followed places the human above God and/or > > Nature! Therefore this philosophy devised by the arrogance of > > man cannot be true. > > > Furthermore, the Philosophy of Idealism really distorts the > > of concept of reality and what is real and what is not. In > > other words; this philosophy is better suited for the worlds of > > schizophrenia than the realm of rational thinking and logic. > > > It is this false philosophy that Einstein followed. So the > > universe of SR and GR turned out to be very similar to the > > universe of Ptolemy, except that rather than being a > > geocentric universe, Einstein's is a human being centric > > universe. However, as there is no privileged individual human > > observer, Einstein had to come up with the idea that there is > > no preferred point of view or frame of reference, and on and on > > with more and more gloobidy goop to make SR and GR > > plausible. > > > All this is much better covered in my copyrighted manuscript > > titled: "The Search for Reality and the Truths." > > > There is one thing I would like to add at this time. I wish that > > all the contributors of this thread on both camps i.e., for and > > against SR would just light up. Einstein was not an evil man. > > Nor did try to pull a hoax on society. However he did make > > mistakes. His greatest mistake was not the idea commonly > > attributed to him, but it was placing greater credence in, and > > accepting the Philosophies of Idealism and Leibniz over the > > philosophy presented by Isaac Newton in Book 3 of Principia. > > > D. Y. Kadoshima > > Dear D. Y. Kadoshim: > > If what you say is true then these two websites I have linked to are > twins: > > http://www.google.com/notebook/public/01717074575303452014/BDQ2RSwoQ-...http://www.google.com/notebook/public/01717074575303452014/BDQ2RSwoQ-... > > Because learning is symmetric, but why do my columns not line up > perfectly? snip > Who is keeping the knowledge out of place? Is it Google? > Just because mathematics is symmetrical, this does not equate to learning or knowledge, the software of computer programs, or time is symmetrical. D.Y.K.
From: kado on 24 Jun 2010 00:17 On Jun 21, 3:26 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: > "train" <gehan.ameresek...(a)gmail.com> wrote in message > >snip > Whales are mammals, whales have no legs. > We establish by definition that all mammals have no legs. Stupid or a hoax? > Androcles doesn't know how a mammal is definied? Or maybe what I post zipped right over his head. D.Y.K.
From: Michael Moroney on 24 Jun 2010 15:10
"kado(a)nventure.com" <kado(a)nventure.com> writes: >On Jun 21, 3:26 pm, "Androcles" <Headmas...(a)Hogwarts.physics_z> wrote: >> Whales are mammals, whales have no legs. >> We establish by definition that all mammals have no legs. Stupid or a hoax? >> >Androcles doesn't know how a mammal is definied? >Or maybe what I post zipped right over his head. Never mind "Androcles" (John Parker), he's a senile old fart who has a (bad) obsession with Einstein, and he doesn't really understand relativity anyway. (space below is reserved for Parker to curse and cuss at me for pointing this out) |