A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Inertial on 7 Mar 2010 02:04 "Y.Porat" <y.y.porat(a)gmail.com> wrote in message news:690819be-c554-4e0b-9eec-c688f6a03827(a)d27g2000yqf.googlegroups.com... > On Mar 4, 8:27 pm, PD <thedraperfam...(a)gmail.com> wrote: >> On Mar 4, 10:24 am, Ste <ste_ro...(a)hotmail.com> wrote: >> >> >> >> > On 4 Mar, 15:54, PD <thedraperfam...(a)gmail.com> wrote: >> >> > > On Mar 4, 1:03 am, Ste <ste_ro...(a)hotmail.com> wrote: >> > > > > > This is what fundamentally sets apart things like creationism >> > > > > > from >> > > > > > science. Whatever other hoops creationism manages to jump >> > > > > > through, it >> > > > > > will never jump through the hoop of naturalism, and that is >> > > > > > what >> > > > > > *fundamentally* sets it apart from science. >> >> > > > > And also FUNDAMENTALLY distinguishes science from religion. >> > > > > Thanks. >> >> > > > Agreed, but then religion in general never claimed to be science, >> >> > > Agreed! And so science is not a religion in the same fashion. >> >> > No, but neither did one religion ever claim to be the other. >> >> > > > and >> > > > traditional religion is almost immediately identifiable by its >> > > > supernaturalism. Creationism is different in that it actually >> > > > claims >> > > > to be scientific in some essential respects. >> >> > > Ah, yes, but as has been demonstrated even to layfolk (Dover v >> > > Kitsmiller), this is an unsupportable claim. >> >> > I agree. I'm glad you brought up that case. I just reviewed the >> > judgment quickly, and apparently the court agrees that the defining >> > essence of science is naturalism. >> >> Gee, I didn't read that into the judgment at all. > > ----------------- > what is all that nonstop spamming about > 'A constant speed of light ' !!! What spamming? > who is the crook behind it ??!! Its called nature
From: Inertial on 7 Mar 2010 02:07 "rotchm" <rotchm(a)gmail.com> wrote in message news:77f3f705-45fc-4505-855b-403619921122(a)o3g2000yqb.googlegroups.com... > >> > and I consider them two >> > interpertations of the same thing. >> >> Not at all. Very different as far as how they explain reality > > > Note that he said "and I consider...interpretations...". He did not > say taht they are the same thing. he interprets them to be the 'same" > or "equivalent". > > Nonetheless, LET and SR have identical predictions (for kinematical/ > optical) effects. > > >> LET has and required a fixed (theoretically undetectable) aether in a >> fixed >> absolute frame. >> SR does not specify nor require anything about an aether > > True. That is a reason why SR confuses many; there is not a "master > reference". > > >> LET has objects physically compressed due to absolute motion thru the >> aether > > True. this can be taken as a postulate of LET or deduced via field > eqs. > >> SR has no absolute motion, so objects are not affected by such motion > > That is why SR confuses many: The objects are not affected yet they > shorten > (measured length diminishes). Some call it "real", "physical", > "visual", "projection" > etc. In LET, there are no such confusions. > > >> LET has processes physically slowed due to absolute motion thru the >> aether > > True. This can be taken as a postulate in LET or deduced as above. > >> SR has no absolute motion, so processes are not affected by such motion > > That is why SR confuses many. The processes are not afected by such > motion yet clocks slow down. > In LET, clocks are affected and is the "cause" of the slowing down of > clocks. > > >> LET has a side-effect of the speed of light being measured as the same in >> all frames of reference, due to measuring with compressed rulers and >> slowed >> clocks, > > True. From highschool kinematics one deduces that although the speed > of light is not iso in i-frames, a (two way) measurement will always > give c. A simple highschool exercise. > > >> SR has no absolute compression and slowing, and the speed of light really >> is >> c > > SR has the side effect that the speed of light is c for all > observers, contrary to other type of waves, contrary to common > kinematics. That is why SR confuses many. > > >> LET has a side-effect of an appearance of the lorentz transforms holding >> on >> measured values, due to measuring with compressed rulers and slowed >> clocks. >> SR has no absolute compression and slowing, so the lorentz transform hold > > As above... > > >> > The LET interpertation had the >> > advantage, for me, of showing how c + or - v could end up being >> > measured c in all frames. > > I too prefer that model. The LET model has advantages as the SR model > has its advantages. > I use both but prefer "LET". > > >> > Given that was possible I no longer had any >> > problem accepting the second postulate. Eventually I became aware >> > that the second postulate wasn't so much an assumption as a >> > stipulation. We will consider the speed of light to be our standard. >> >> No .. it is an observed fact. Not a stipulation > > It is a stipulation. In fact it is a "defintion". > What ever the behavior of light, it is used as a standard to measure > lengths. Only because it has been MEASURED to behave as SR says. It is an observed 'fact'. Nature came first on this one .. light DOES travel at c in all frames of reference. That means we CAN use the speed of light to define length to give a very easily reproduced and accurate standard for length. > Length has an operational defintion that uses the integer 299792458. > This definition implies/makes the speed of light constant. > > > Who owes me 2 cents now ? :) No idea.
From: Inertial on 7 Mar 2010 02:08 "Y.Porat" <y.y.porat(a)gmail.com> wrote in message news:fe409bc5-8cb7-40c9-85dc-a5a000ea7e83(a)z4g2000yqa.googlegroups.com... > On Mar 5, 1:51 pm, "Inertial" <relativ...(a)rest.com> wrote: >> "Y.Porat" <y.y.po...(a)gmail.com> wrote in message >> >> news:868926cb-233d-417e-86c8-cd8987c43419(a)q16g2000yqq.googlegroups.com... >> >> >> >> > On Mar 4, 7:44 pm, PD <thedraperfam...(a)gmail.com> wrote: >> >> On Mar 4, 11:09 am, Ste <ste_ro...(a)hotmail.com> wrote: >> >> >> > On 4 Mar, 16:48, mpalenik <markpale...(a)gmail.com> wrote: >> >> >> > > On Mar 4, 10:19 am, Ste <ste_ro...(a)hotmail.com> wrote: >> >> >> > > > On 4 Mar, 12:19, "Inertial" <relativ...(a)rest.com> wrote: >> >> >> > > > > "Ste" <ste_ro...(a)hotmail.com> wrote in message >> >> >> > > > > > Not really, because if the total acceleration is small, then >> >> > > > > > so >> >> > > > > > is the >> >> > > > > > speed. >> >> >> > > > > That is a nonsense argument. Acceleration can be small and >> >> > > > > speeds very >> >> > > > > large. >> >> >> > > > When I went to school, you could not have a large change of >> >> > > > speed >> >> > > > with >> >> > > > only a small amount of total acceleration. >> >> >> > > The problem is your use of the term "total acceleration". If by >> >> > > total >> >> > > acceleration, you mean integral(a dt), then yes, you are correct. >> >> > > However, there is already a word for integral(a dt) -- it's called >> >> > > "the change in velocity". The term "total acceleration" isn't >> >> > > actually defined. Acceleration is defined, velocity is defined, >> >> > > deltav is defined. But "total acceleration is not". >> >> >> > Essentially, I'm defining "total acceleration" as something akin to >> >> > total force, so that even though the force may be small, if it >> >> > continues for a long time then the total force will be the same as >> >> > if >> >> > a large force was applied for a short period of time. In this way, >> >> > if >> >> > the application of force is what is causing either part or the whole >> >> > of the time dilation effect, then it is the final speed that counts, >> >> > not how quickly the object reached that speed. >> >> >> Indeed. This should tell you that it is not the details of the >> >> acceleration that matter. >> >> The overly simplistic statement would be, "Yes, you see that is why >> >> SR's effects are based on speed, not on acceleration." >> >> >> In fact, there is a speed time dilation effect on GPS satellites, >> >> which are going around in a circular path at constant speed, relative >> >> to earth clocks, and accounting for this is crucial to their proper >> >> operation. This is the same speed dilation effect, though different >> >> size, as seen in muons in a circulating ring. (Since, by the way, the >> >> GPS satellites are certainly not inside a magnetic ring but still >> >> experience time dilation properly calculated by SR, this is another >> >> good way to be sure that the magnetic ring is not what's responsible >> >> for the time dilation of the muons.) >> >> >> Regarding something I alluded to earlier, though, what really matters >> >> is how straight the path through spacetime is. We're used to thinking >> >> that the shortest path through space is the straight one (and that's >> >> right), but the straightest path through spacetime yields the LONGEST >> >> duration. Any change in motion (such as an acceleration) introduces a >> >> kink in this path (something that can be illustrated visually very >> >> easily) and so lowers the duration. Why this is, has to do with the >> >> structure of spacetime and we could discuss that. But this is perhaps >> >> the most intuitive way (once these concepts are explained) to >> >> understand why the traveling twin returns younger. >> >> >> > > Also, you could just be dealing with a system where the velocity >> >> > > started out high and you never measured any acceleration. >> >> >> > Indeed. >> >> > ---------------------- >> > (:-) >> > to mix **biologic process** with >> > inorganic physics >> > is ridiculous!!! >> >> He didn't .. there was no biologic process mentioned in the above. >> >> > (i said it in a big understatement ...(:-) >> > Y.Porat >> > ----------------------- > > here is a quote from PD > quote > > 'and so lowers the duration. Why this is, has to do with the > structure of spacetime and we could discuss that. But this is perhaps > the most intuitive way (once these concepts are explained) to > understand why the traveling twin returns younger. > end of quote > ------------- > so the tarveling twin returns younger ???!!! Yes. Gees, don't you know this already? > 2 > if you dont rmind > EM radiation HAS MASS! Nope > therefore it i influenced by gravity By space curvature .. yes > SIMILAR BUT NOT EXACTLY AS ANY OTHER MASS!! > no curvature and no shmervature of space Except nature behaves as though there is. Nature knows better than you > but that is again not for born parrots > BYE I wish
From: Inertial on 7 Mar 2010 02:11 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:1888cc4e-8e62-42ae-8716-b1340d6daa3e(a)t20g2000yqe.googlegroups.com... > On Mar 5, 12:12 am, "Inertial" <relativ...(a)rest.com> wrote: >> "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message >> >> news:7806715d-93d2-49ff-ad67-6dac8ea64d8c(a)e7g2000yqf.googlegroups.com... >> >> >> >> >> >> > On Mar 4, 10:48 am, PD <thedraperfam...(a)gmail.com> wrote: >> >> On Mar 3, 10:59 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: >> >> >> > On Mar 3, 11:21 am, PD <thedraperfam...(a)gmail.com> wrote: >> >> >> > > On Mar 2, 8:12 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: >> >> >> > > > > It is not a function of finite propagation speeds, this we >> >> > > > > know, >> >> > > > > because we took into account the finite propagation speeds in >> >> > > > > our >> >> > > > > procedure for determining simultaneity/nonsimultaneity. Do you >> >> > > > > not >> >> > > > > remember that? >> >> >> > > > I beg to differ. It is not a "mere" or "simple" function of >> >> > > > finite >> >> > > > propagation speed, but it *is* a function of it IMO. RoS only >> >> > > > took >> >> > > > it >> >> > > > into account by allowing us to use different time coordinates in >> >> > > > each >> >> > > > frame. If the speed of light was infinite there would be no >> >> > > > RoS. >> >> >> > > I disagree. All that is needed in relativity of simultaneity is a >> >> > > signal speed that can be VERIFIED to be the same from both events >> >> > > by >> >> > > either observer. >> >> >> > Well you are going to have problems with that. There is no way to >> >> > *know* that the speed is the same both ways. >> >> >> Yes, there is. That's what isotropy experiments have determined. I'm >> >> surprised you weren't aware of this. >> >> > Do you mean like this one? >> >> >http://mysite.verizon.net/cephalobus_alienus/papers/Gagnon_et_al_1988... >> >> > The author is kind enough to point out problems in some similar >> > experiments, while failing to notice any in his own. >> >> > For example, has he made any assumption about contraction of his >> > equipment in the direction of motion? Tom Roberts has written posts >> > in this group showing where some of these experiments are in effect >> > two way measurements. >> >> >> > That is why Einstein >> >> > wrote, "But it is not possible without further assumption to >> >> > compare, >> >> > in respect of time, an event at A with an event at B. We have so far >> >> > defined only an ``A time'' and a ``B time.'' We have not defined a >> >> > common ``time'' for A and B, for the latter cannot be defined at all >> >> > unless we establish by definition that the ``time'' required by >> >> > light >> >> > to travel from A to B equals the ``time'' it requires to travel from >> >> > B >> >> > to A." >> >> >> > > Since the distance from the events to the observer is >> >> > > equal, as verifiable at any time by each observer, we learn from >> >> > > this >> >> > > that each observer KNOWS the propagation delays from each event to >> >> > > the >> >> > > observer are equal. This acknowledges the propagation delays >> >> > > completely, but simply allows for verification that they are the >> >> > > same. >> >> >> > Assuming the speed of light is the same in both directions. >> >> >> Which is an experimentally confirmed fact. Done well after Einstein's >> >> comments on the matter, by the way. >> >> > Provide a link to an experiment and I'll take a look. >> >> >> > > Then the determination of simultaneity or nonsimultaneity of the >> >> > > original events is completely unambiguous: If the observer >> >> > > receives >> >> > > both signals at the same time, then (because the propagation >> >> > > delays >> >> > > are the same) the original events were simultaneous; if the >> >> > > observer >> >> > > receives both signals at different times, then (because the >> >> > > propagation delays are the same) the original events were >> >> > > nonsimultaneous. >> >> >> > > Then the frame-dependence of simultaneity follows directly from >> >> > > the >> >> > > experimental *observation* that for the same pair of events, one >> >> > > observer correctly and unambiguously concludes the events were >> >> > > simultaneous, and the other observer correctly and unambiguously >> >> > > concludes the events were nonsimultaneous. >> >> >> > > You've mentioned in the past that you found your disbelief in >> >> > > relativity stems from being unable to find a good, understandable >> >> > > explanation of it. I invite you to read back on this thread where >> >> > > I >> >> > > was trying to explain to Ste (who has a similar complaint) how >> >> > > this >> >> > > comes about. >> >> >> > No need. Lorentz showed how all frames could measure the speed of >> >> > light to be c. That in effect confirms the second postulate, which >> >> > is >> >> > the stumbling block for many. >> >> >> Well then, you are just *choosing* what you would like to believe. In >> >> this case, lodging a complaint against relativity that it is not well >> >> explained, when you are not interested in pursuing a better >> >> explanation, having settled on LET instead, is a bit on the >> >> disingenuous side. >> >> > You are reading more into that than what I wrote. I am not choosing >> > LET over SR. They use the same math >> >> Yes >> >> > and I consider them two >> > interpertations of the same thing. >> >> Not at all. Very different as far as how they explain reality >> >> LET has and required a fixed (theoretically undetectable) aether in a >> fixed >> absolute frame. >> SR does not specify nor require anything about an aether >> >> LET has objects physically compressed due to absolute motion thru the >> aether >> SR has no absolute motion, so objects are not affected by such motion >> >> LET has processes physically slowed due to absolute motion thru the >> aether >> SR has no absolute motion, so processes are not affected by such motion >> >> LET has a side-effect of the speed of light being measured as the same in >> all frames of reference, due to measuring with compressed rulers and >> slowed >> clocks, even though its only really has that speed relative to the >> aether, >> SR has no absolute compression and slowing, and the speed of light really >> is >> c >> >> LET has a side-effect of an appearance of the lorentz transforms holding >> on >> measured values, due to measuring with compressed rulers and slowed >> clocks. >> SR has no absolute compression and slowing, so the lorentz transform hold > > Read what I actually wrote, not what you think I wrote. I wrote, "I > consider them two interpertations of the same thing." The events are > the same. The predictions are the same. The interpertation of why > things appear the way they do is different. OK .. I understand what you meant now. My comments about the differences between the two stand, of course
From: Inertial on 7 Mar 2010 02:13
"kenseto" <kenseto(a)erinet.com> wrote in message news:19d3efdd-b1d3-433f-ab2f-68e6e4d8eb50(a)q23g2000yqd.googlegroups.com... > On Mar 5, 12:12 am, "Inertial" <relativ...(a)rest.com> wrote: >> "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message >> >> news:7806715d-93d2-49ff-ad67-6dac8ea64d8c(a)e7g2000yqf.googlegroups.com... >> >> >> >> >> >> > On Mar 4, 10:48 am, PD <thedraperfam...(a)gmail.com> wrote: >> >> On Mar 3, 10:59 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: >> >> >> > On Mar 3, 11:21 am, PD <thedraperfam...(a)gmail.com> wrote: >> >> >> > > On Mar 2, 8:12 pm, Bruce Richmond <bsr3...(a)my-deja.com> wrote: >> >> >> > > > > It is not a function of finite propagation speeds, this we >> >> > > > > know, >> >> > > > > because we took into account the finite propagation speeds in >> >> > > > > our >> >> > > > > procedure for determining simultaneity/nonsimultaneity. Do you >> >> > > > > not >> >> > > > > remember that? >> >> >> > > > I beg to differ. It is not a "mere" or "simple" function of >> >> > > > finite >> >> > > > propagation speed, but it *is* a function of it IMO. RoS only >> >> > > > took >> >> > > > it >> >> > > > into account by allowing us to use different time coordinates in >> >> > > > each >> >> > > > frame. If the speed of light was infinite there would be no >> >> > > > RoS. >> >> >> > > I disagree. All that is needed in relativity of simultaneity is a >> >> > > signal speed that can be VERIFIED to be the same from both events >> >> > > by >> >> > > either observer. >> >> >> > Well you are going to have problems with that. There is no way to >> >> > *know* that the speed is the same both ways. >> >> >> Yes, there is. That's what isotropy experiments have determined. I'm >> >> surprised you weren't aware of this. >> >> > Do you mean like this one? >> >> >http://mysite.verizon.net/cephalobus_alienus/papers/Gagnon_et_al_1988... >> >> > The author is kind enough to point out problems in some similar >> > experiments, while failing to notice any in his own. >> >> > For example, has he made any assumption about contraction of his >> > equipment in the direction of motion? Tom Roberts has written posts >> > in this group showing where some of these experiments are in effect >> > two way measurements. >> >> >> > That is why Einstein >> >> > wrote, "But it is not possible without further assumption to >> >> > compare, >> >> > in respect of time, an event at A with an event at B. We have so far >> >> > defined only an ``A time'' and a ``B time.'' We have not defined a >> >> > common ``time'' for A and B, for the latter cannot be defined at all >> >> > unless we establish by definition that the ``time'' required by >> >> > light >> >> > to travel from A to B equals the ``time'' it requires to travel from >> >> > B >> >> > to A." >> >> >> > > Since the distance from the events to the observer is >> >> > > equal, as verifiable at any time by each observer, we learn from >> >> > > this >> >> > > that each observer KNOWS the propagation delays from each event to >> >> > > the >> >> > > observer are equal. This acknowledges the propagation delays >> >> > > completely, but simply allows for verification that they are the >> >> > > same. >> >> >> > Assuming the speed of light is the same in both directions. >> >> >> Which is an experimentally confirmed fact. Done well after Einstein's >> >> comments on the matter, by the way. >> >> > Provide a link to an experiment and I'll take a look. >> >> >> > > Then the determination of simultaneity or nonsimultaneity of the >> >> > > original events is completely unambiguous: If the observer >> >> > > receives >> >> > > both signals at the same time, then (because the propagation >> >> > > delays >> >> > > are the same) the original events were simultaneous; if the >> >> > > observer >> >> > > receives both signals at different times, then (because the >> >> > > propagation delays are the same) the original events were >> >> > > nonsimultaneous. >> >> >> > > Then the frame-dependence of simultaneity follows directly from >> >> > > the >> >> > > experimental *observation* that for the same pair of events, one >> >> > > observer correctly and unambiguously concludes the events were >> >> > > simultaneous, and the other observer correctly and unambiguously >> >> > > concludes the events were nonsimultaneous. >> >> >> > > You've mentioned in the past that you found your disbelief in >> >> > > relativity stems from being unable to find a good, understandable >> >> > > explanation of it. I invite you to read back on this thread where >> >> > > I >> >> > > was trying to explain to Ste (who has a similar complaint) how >> >> > > this >> >> > > comes about. >> >> >> > No need. Lorentz showed how all frames could measure the speed of >> >> > light to be c. That in effect confirms the second postulate, which >> >> > is >> >> > the stumbling block for many. >> >> >> Well then, you are just *choosing* what you would like to believe. In >> >> this case, lodging a complaint against relativity that it is not well >> >> explained, when you are not interested in pursuing a better >> >> explanation, having settled on LET instead, is a bit on the >> >> disingenuous side. >> >> > You are reading more into that than what I wrote. I am not choosing >> > LET over SR. They use the same math >> >> Yes >> >> > and I consider them two >> > interpertations of the same thing. >> >> Not at all. Very different as far as how they explain reality >> >> LET has and required a fixed (theoretically undetectable) aether in a >> fixed >> absolute frame. >> SR does not specify nor require anything about an aether >> >> LET has objects physically compressed due to absolute motion thru the >> aether >> SR has no absolute motion, so objects are not affected by such motion >> >> LET has processes physically slowed due to absolute motion thru the >> aether >> SR has no absolute motion, so processes are not affected by such motion >> >> LET has a side-effect of the speed of light being measured as the same in >> all frames of reference, due to measuring with compressed rulers and >> slowed >> clocks, even though its only really has that speed relative to the >> aether, >> SR has no absolute compression and slowing, and the speed of light really >> is >> c >> >> LET has a side-effect of an appearance of the lorentz transforms holding >> on >> measured values, due to measuring with compressed rulers and slowed >> clocks. >> SR has no absolute compression and slowing, so the lorentz transform hold >> >> > The LET interpertation had the >> > advantage, for me, of showing how c + or - v could end up being >> > measured c in all frames. >> >> In SR there is no c+v or c-v, because there is no fixed absolute aether >> frame in which light really travels at c. > > Then why did Einstein say that M' is runshing toward the light front > from the front (c+v) and receding away from the light front from the > rear (c-v)?? Closing and separation speeds. This has been explained to you over and over. |