A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Peter Webb on 14 Feb 2010 09:44 "mpc755" <mpc755(a)gmail.com> wrote in message news:24b1dbfc-e19c-4c2e-a7f7-6a3601ea13da(a)q16g2000yqq.googlegroups.com... On Feb 14, 1:31 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "mpc755" <mpc...(a)gmail.com> wrote in message > > news:49c69202-f525-4bba-bfa0-09b662433837(a)s33g2000prm.googlegroups.com... > On Feb 14, 1:12 am, "Peter Webb" > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > Now, here's the kicker. If the Observers on the train know they are > > moving relative to water at rest with respect to the embankment, the > > Observers on the train will be able to factor in the trains motion > > relative to the water and calculate back and determine the lightning > > strikes were in fact, simultaneous with respect to the water > > > _______________________________________ > > Yes. > > > and conclude the lightning strikes were simultaneous, in nature. > > > __________________________________________ > > No. Nowhere in the 200 lines that preceded this do you show that > > reference > > frame of the water is the reference frame of "nature". It doesn't even > > make > > any sense. > > Light propagates at a constant speed with respect to the state of the > medium in which it exists. > > __________________________________________ > No. > > The Observers on the train know their state > with respect to the state of the water and are able to conclude > correctly the lightning strikes at A/A' and B/B' were simultaneous, in > nature. > > ________________________________ > If by "in nature", you mean the "in the frame of reference of the earth > considered as an inertial frame", then yes. If "in nature" means something > else, perhaps you should explain exactly what "in nature" is supposed to > mean. As long as any Observer is able to factor in their state with respect to the state of the medium in which the light propagates being at rest then the Observer is able to conclude when the lightning strikes occurred in nature. ______________________________________ So the inertial reference frame of nature is the rest frame in which light moves at a constant rate? What reference frame is that, relative to the Sun?
From: Darwin123 on 14 Feb 2010 10:07 On Feb 13, 8:29 am, Ste <ste_ro...(a)hotmail.com> wrote: > A speed (i.e. a mesure of distance traversed within a period of time) > cannot possibly be measured constant in all directions within a frame, > *and* constant between frames, where the frames themselves are moving > at a speed relative to each other. So how the hell does one reconcile > this physically? By claiming that the observers, the measuring instruments, are in physically distinct states. When Einstein or anyone else refers to "different inertial frames," he is really talking about measuring instruments in "physically distinct states." The rulers and clocks in one reference frame are operating differently than the rulers and clocks in another reference frame. However, the measured quantities themselves depend on the physical state of the instruments that determine them. If there are two rulers with a nonzero relative velocity between them, they are in physically distinct states. Each ruler will belong to different inertial frames. Two clocks in different reference frames may be "identical" in terms of chemical composition, number of atoms, and other covariant quantities. They may also be "identical" in terms of being at equilibrium with their immediate surroundings. If so, they are not physically identical in terms of certain noncovariant quantities. They are different in when the length of times since they were synchronized, and in the rate with which they tick. However, what those differences are depend on which clock is used to determine them. As far as the users of each clock is concerned, it is the other clock that is ticking slower. If the two users communicate and try to resolve the issue, each user will disagree as to when the other clock was last synchronized.
From: kenseto on 14 Feb 2010 10:48 On Feb 13, 8:48 pm, Sam Wormley <sworml...(a)gmail.com> wrote: > On 2/13/10 5:06 PM, kens...(a)erinet.com wrote: > > > > > > > On Feb 13, 1:31 pm, Sam Wormley<sworml...(a)gmail.com> wrote: > >> On 2/13/10 10:24 AM, kenseto wrote: > > >>> The speed of light is a constant math ratio in all frames as follows: > >>> Light path length of the observer's physical ruler (299,792,458 m > >>> long) is assumes to be its physical length/the absolute time content > >>> for a clock second co-moving with the ruler. > > >> I can come up with an infinite number of ratios to come up with > >> the nine digits from the human definition of the speed of light! > > >> The real point is that the speed of light is a PHYSICAL CONSTANT > >> observed in nature. How it is defined and what numbers we humans > >> assign to the speed of light is arbitrary! > > >> Units of distance are DERIVED from the speed of light, not the > >> other way around. > > > ROTFLOL....hey wormy do you realize what you are saying???? The speed > > of light is born from a material meter stick. Hey wormy do you deny > > that your mother is not your mother? > > Seto--The speed of light exist independent of human. Meter sticks > are not require for it relativistic effects to show up. The speed > of light has been observed as an unchanging constant for so long > that human adopted it as part of the definition of the meter, a > unit of distance! No wormy....the speed of light is a constant by definition. > > I'm glad you get a good laugh out of that, Seto!- Hide quoted text - > > - Show quoted text -
From: mpc755 on 14 Feb 2010 10:55 On Feb 14, 9:44 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "mpc755" <mpc...(a)gmail.com> wrote in message > > news:24b1dbfc-e19c-4c2e-a7f7-6a3601ea13da(a)q16g2000yqq.googlegroups.com... > On Feb 14, 1:31 am, "Peter Webb" > > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > "mpc755" <mpc...(a)gmail.com> wrote in message > > >news:49c69202-f525-4bba-bfa0-09b662433837(a)s33g2000prm.googlegroups.com.... > > On Feb 14, 1:12 am, "Peter Webb" > > > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > Now, here's the kicker. If the Observers on the train know they are > > > moving relative to water at rest with respect to the embankment, the > > > Observers on the train will be able to factor in the trains motion > > > relative to the water and calculate back and determine the lightning > > > strikes were in fact, simultaneous with respect to the water > > > > _______________________________________ > > > Yes. > > > > and conclude the lightning strikes were simultaneous, in nature. > > > > __________________________________________ > > > No. Nowhere in the 200 lines that preceded this do you show that > > > reference > > > frame of the water is the reference frame of "nature". It doesn't even > > > make > > > any sense. > > > Light propagates at a constant speed with respect to the state of the > > medium in which it exists. > > > __________________________________________ > > No. > > > The Observers on the train know their state > > with respect to the state of the water and are able to conclude > > correctly the lightning strikes at A/A' and B/B' were simultaneous, in > > nature. > > > ________________________________ > > If by "in nature", you mean the "in the frame of reference of the earth > > considered as an inertial frame", then yes. If "in nature" means something > > else, perhaps you should explain exactly what "in nature" is supposed to > > mean. > > As long as any Observer is able to factor in their state with respect > to the state of the medium in which the light propagates being at rest > then the Observer is able to conclude when the lightning strikes > occurred in nature. > > ______________________________________ > > So the inertial reference frame of nature is the rest frame in which light > moves at a constant rate? > > What reference frame is that, relative to the Sun? The reference frame is the state of the aether the light propagates through. And this includes the state of the aether which exists in any and all mediums in which the light propagates. For example, we get together and synchronize our atomic clocks. As we move away from each other we have to know our state with respect to the aether in order to know how our atomic clocks are being effected by the increase and decrease in the associated aether pressure our movement through the aether causes to our atomic clocks. As long as we have this information and we know the state of the mediums in which the light waves propagate we will always be able to calculate back and arrive at the same conclusion as to when the lightning strikes occurred. It doesn't matter if the light waves propagate through a tube of moving water or half the beam is reflected out of the tube and propagates through a block of glass on a train or whatever, as long as you know your state with respect to the aether when the light reaches you and I know my state with respect to the aether when the light reaches me and we know the state of the mediums in which the light waves propagated we will always be able to calculate back and arrive at the same conclusion as to when the flash occurred.
From: mpc755 on 14 Feb 2010 12:26
On Feb 14, 12:49 am, mpc755 <mpc...(a)gmail.com> wrote: > On Feb 13, 8:29 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > I've been absolutely racking my brain (to the point of getting a > > headache) for the last few days about this issue, and it's clear that > > the speed of light (where light is either considered in the form of a > > ballistic photon, or a wave-cycle) cannot, physically, be constant in > > all relative frames, and at the same time be constant when travelling > > between two objects in two different frames. It's a physical and > > logical impossibility. > > > It's also clear that velocities cannot be additive (in the form of > > speed of bullet+speed of gun), and nor can they be subtractive > > relative to a background medium (in the form of speed of propagation > > in medium-speed of source). > > > Take an illustration: > > > A C > > B > > > Where A and B are atoms that pass infinitely close to each other. In > > the illustration, A and B are separated from C by a distance L. A and > > C are stationary relative to each other. B is moving, and approaching > > C at a speed S. A pulse is emitted from both A and B simultaneously > > towards C, at the point when A and B are equidistant from C. > > > Now, clearly, if velocities were additive, then light from B would > > reach C much quicker than light from A. We don't see that, so we can > > dismiss that immediately. > > > Next, if velocities were subtractive, like sound, well that seems like > > a compelling explanation for what we see, which is that light from > > both A and B travel towards C at the same speed. But the presence of > > an absolute medium seems to fall down when one considers that, to be > > consistent with observation, the speed of propagation orthogonal to > > the direction of travel must be the same as the speed in the direction > > of travel. > > > A speed (i.e. a mesure of distance traversed within a period of time) > > cannot possibly be measured constant in all directions within a frame, > > *and* constant between frames, where the frames themselves are moving > > at a speed relative to each other. So how the hell does one reconcile > > this physically? > > Light propagates at 'c' with respect to the aether. > > Think of the train and the embankment in Einstein's train gedanken to > be filled with water. Consider the water to be at rest with respect to > the embankment. Consider the clocks on the train to consist of paddles > for the second hand. > > Let's have three Observers on the embankment all standing at M and > they synchronize their clocks. Now, have two of the Observers walk to > A and B from M. As two of the Observers walk towards A and B they are > walking through the water. This increases the water pressure on the > paddle and their clocks 'tick' slower than the Observer at M. Once the > Observers get to A and B they stop and now their clocks 'tick' at the > same rate as the clock at M, even though if you could see the time on > all three clocks simultaneously the clocks at A and B would be > slightly behind the clock at M. > > There are three Observers on the train at M'. Since the train is > moving through the water the clocks on the train are already 'ticking' > slower than the clocks on the embankment due to the increase the water > pressure the clocks are under because the clocks are moving relative > to the water while the clocks on the embankment are at rest with > respect to the water. > > The three Observers on the train synchronize their clocks. Two of the > Observers start walking towards A' and B'. The Observer walking > towards B' will have his clock 'tick' the slowest as they walk because > their clock not only has to deal with the train moving through the > water but their clock also has to deal with the additional rate at > which the clock is moving relative to the water because the Observer > walking towards B' is walking against the flow of the water. The > Observer walking towards A' is walking with the flow of water and > their clock will actually tick faster than the clock which remains at > M'. > > Lightning strikes occur at A/A' and B/B'. The water propagates through > the water at rest with respect to the embankment. The light from the > lightning strikes arrives at M simultaneously. This correlates with > the time on the clocks at A and B. > > The light from the lightning strikes at B/B' arrives at M' and then > the light from the lightning strikes at A/A' arrives at M'. Now, if > the Observers on the train do not know their state with respect to the > water they will conclude the lightning strike at B/B' occurred prior > to the lightning strike at A/A'. This matches to what the clocks at B' > and A' say occurred. The reason for this is because when the clock was > walked to B' it was under additional water pressure and 'ticked' > slower than the clock walked to A'. Let's use some numbers to try and > make this less confusing. The three Observers on the train synchronize > their clocks to be 12:00:00. Let's say it takes them one minute, as > determined by an outside observer, to walk to A' and B'. Because the > clock being walked to B' is under additional water pressure, when the > Observer gets to B', their clock will read 12:00:59. The clock being > walked to A', since it is under less water pressure and ticks faster, > will read 12:01:01. Now, if the lightning strikes take place at this > moment and the light from B/B' reaches M' and then the light from A/A' > reaches M' all three Observers agree the lightning strike at B/B' > occurred prior to the lightning strike at A/A' because the clock at B/ > B' read 12:00:59 and the clock at A/A' read 12:01:01 at the time of > the lightning strikes. > > Now, here's the kicker. If the Observers on the train know they are > moving relative to water at rest with respect to the embankment, the > Observers on the train will be able to factor in the trains motion > relative to the water and calculate back and determine the lightning > strikes were in fact, simultaneous with respect to the water and > conclude the lightning strikes were simultaneous, in nature. When the Observers arrive at A and B their clocks will be slightly behind the clock at M because the clocks moved relative to the aether at rest with respect to the embankment. Lets say the clock at M reads 12:01:00 and the clocks at A and B read 12:01:00.5. The Observers at A and B, using SR, know their clocks ticked slower than the clock at M and factoring this in the Observers at A and B reset their clocks accordingly to 12:01:00. If you could see all three clocks simultaneously all three will be the same time. When the Observers arrive at A' and B' they also factor in the SR calculations based up their motion relative to the clock at M'. When the Observers arrive at A' and B' their clocks stated the time as 12:01:01.5 and 12:00:59.5, respectively. The Observers at A' and B' reset their clocks to 12:01:01 and 12:00:59, respectively. If you could see the clocks at A', M', and B' simultaneously the clocks would read 12:01:01, 12:01:00, and 12:00:59, respectively. It is easy to understand how lightning strikes on the embankment arrive at the 'correct' times regardless if there are lightning strike at A and B which arrive at M or a single lightning strike at M which arrives at A and B. It is not as straight forward when discussing the lightning strikes on the train. Let's first assume the Observers on the train do not realize they are moving relative to the water. Lightning strikes at A/ A' and B/B' determined to be simultaneous by the Observer at M will occur at A' at 12:01:01 and at B' at 12:00:59. The train is moving relative to the water the light waves propagate through. The light from B' is flowing with the water relative to the train and the light from A' is flowing against the water relative to the train. The light from B' will arrive prior to the light from A'. When the three Observers on the train discuss when the lightning strikes occurred, they are all in agreement the lightning strike at B' occurred prior to the lightning strike at A'. If there is a single lightning strike at M' at 12:01:00. The light waves propagating towards B' are propagating against the flow of water relative to the train and the light waves propagating towards A' are propagating with the flow of water relative to the train. Let's assume it takes two seconds for the light waves to reach B' and one second for the light waves to reach A'. When the light waves reach the Observers at A' and B' both of their clocks read 12:01:02. When the three Observers discuss when the lightning strike occurred at M', they are all in agreement the lightning strike at M' occurred at 12:01:01. Now, again for the kicker. If the Observers on the train know they are moving relative to the water the light waves propagate through and factor this in when determining when the lightning strikes occurred in nature, the Observers on the train, and in fact any Observer in any frame of reference, will all arrive at the same conclusion as to when the lightning strikes occurred in nature. |