SR/GR use absolute time to synchronize the GPS clocks with the ground clock.
in [Physics]
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From: Michael Moroney on 7 May 2010 13:56 Sam Wormley <swormley1(a)gmail.com> writes: >On 5/7/10 10:32 AM, Michael Moroney wrote: >> My posts are made on the assumption that all GR effects on the GPS >> satellites can be simplified to the gravitational well effect of >> ~45uS/day and the motion effects of ~7uS/day. > GTR covers everything! SR may be more convenient for some calculations > but GTR encompasses SR. Both theories need not be applied separately. I know that. But the satellite in orbit is constantly accelerating, its motion as seen from earth is curved and there are probably several effects I haven't considered. I'm assuming for this discussion the major effects are the gravity well effect and the orbital velocity effect, and others are minor in comparison. Also, for this discussion even know GR will have a single function that considers motion and gravity effects and everything else that will spit out a single time dilation value, the two effects can be considered as if independent and their contributions add. Remember, this discussion isn't exclusive to physics PhDs, the biggest contributor apparently doesn't understand SR but thinks he does.
From: kenseto on 9 May 2010 10:13 On May 7, 1:56 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) wrote: > Sam Wormley <sworml...(a)gmail.com> writes: > >On 5/7/10 10:32 AM, Michael Moroney wrote: > >> My posts are made on the assumption that all GR effects on theGPS > >> satellites can be simplified to the gravitational well effect of > >> ~45uS/day and the motion effects of ~7uS/day. > > GTR covers everything! SR may be more convenient for some calculations > > but GTR encompasses SR. Both theories need not be applied separately. > > I know that. But the satellite in orbit is constantly accelerating, So why did you treat the GPS clock as inertial and then claim that the GPS sees the ground clock as 7 us/day slow and from the ground clock point of view it also sees the GPS as 7 us/day slow?????? Do you just make up stuff as you go along???? Ken Seto >its > motion as seen from earth is curved and there are probably several effects > I haven't considered. I'm assuming for this discussion the major effects > are the gravity well effect and the orbital velocity effect, and others > are minor in comparison. Also, for this discussion even know GR will have > a single function that considers motion and gravity effects and everything > else that will spit out a singletimedilation value, the two effects can > be considered as if independent and their contributions add. > > Remember, this discussion isn't exclusive to physics PhDs, the biggest > contributor apparently doesn't understand SR but thinks he does.
From: kenseto on 9 May 2010 10:32 On May 7, 11:51 am, moro...(a)world.std.spaamtrap.com (Michael Moroney) wrote: > kenseto <kens...(a)erinet.com> writes: > >On May 5, 4:23 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) > >wrote: > >> kenseto <kens...(a)erinet.com> writes: > >> >On May 4, 5:03 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) > >> >wrote: > >> >> Nope, that's correct. SR effects of motion always cause the movingclockto run slow. > >> >"Nope, that's correct." ????? > > >> "That" refers to the statement "Satellite seesgroundclockrunning ~45uS > >> slow due to gravity and ~7uS slow due to motion = ~52uS/day slow.". > >> It is correct. > >No that's not correct....how come the gravity effect is not > >reversible...that is thegroundclocksees theGPS45us/day fast and > >theGPSsees thegroundclock~45 us/day slow..... > > That's because no matter which frame you view it from, thegroundobserver > is closer to a gravitating object (the Earth) than theGPSsatellite. > > >and yet when it > >comes to the SR effect you claimed that the velocity effect is > >reversible....that is the gorundclocksees the SR effect on theGPS > >is 7 us/day slow and theGPSsees the SR effect on thegroundclock > >also ~7us/day slow? > > That is because which object is in motion does depend on your frame of > reference. Someone on thegroundsees theGPSsatellites as moving, so > will see theirclockas running slow (SR effects only). Someone riding > aGPSsatellite will see the satellite as stationary, but will see anyone > fixed to the Earth as moving rapidly, so will see the Earth person'sclockas running slow. > > PD is correct. You need to learn SR! > > >> >No to your statement....the SR effect of motion depends on who is > >> >doing the moving. For example if you accelerated away from me you are > >> >the one who is doing the moving....so yourclockis running slower > >> >than myclock. From your point of view myclockis running faster than > >> >yourclock. > > >> When you said "accelerated" did you really want to write "accelerated"? > >> In that case there is non-inertial motion and SR does not apply. If > >> you really did mean constant motion (no acceleration), then there is > >> RELATIVE motion. I see you as moving away from me, you see me as moving > >> away from you. We are both correct for our own frames, one co-moving > >> with you, the other co-moving with me. I see yourclockas slowed, you > >> see myclockas slowed. > >Hey idiot theGPSwas accelerated from thegroundclock.... > > So are you now saying the satelliteclock"remembers" that it was once > accelerated into space, and will therefore run at a different rate > from then on? Yes...after acceleration the SR effect on the satellite clock is permanently 7 us/day slow. > > What if, I took some cesium, accelerated it to near c in a particle > accelerator, then stopped it and mixed it with cesium that was never > accelerated, and used it in a cesiumclock? Will the two "kinds" of > cesium atom try to make theclocktick at two different rates? Hey idiot when you make the Cs atoms come to rest with your Cs atoms then they will operate the same as your Cs atoms. > > >so why did > >you claim that from theGPSpoint of view the SR effect on theground > >clockis also 7 us/day slow? > > Please learn some SR. An observer observes aclockmoving relative > to him as running slow. ROTFLOL....you are the one who need to learn SR....what you said is an erroneous assumption of the PoR that every SR observer is in a state of absolute rest. This is wrong. The rate of two relative clock A and B is as follows: 1. A is running fast compared to B. 2. B is running slow compared to A. > > >> >The redefinedGPSsecond > > >> THERE IS NO SUCH THING!!!! > >Answer me this question: When theGPSwant to signal the passage of a > >second to the gorundclockdoes it sends the signal after > >9,192,631,770 periods of Cs 133 radiation or does it sends the signal > >after the passage of (9,192,631,770 + 4.15) periods of Cs 133 > >radiation? > > The onboardclockwill tick at 9,192,631,770 periods of Cs 133 radiation > per second, exactly (by definition). But this definition is not used by the GPS. It uses the redefined second of (7,192,631,770 +4.15) periods of Cs 133 radiation. >AGPSsatelliteclockwill also > generate a signal that ticks at one pulse per 9,192,631,774.15 periods of > Cs 133, which will be received on thegroundas a highly accurate 1 pulse > per secondclock. So it uses the redefined second to send signals....that means that the GPS second is redefined. Ken Seto > > No "redefinition" of a second.
From: Sam Wormley on 9 May 2010 11:31 On 5/9/10 9:32 AM, kenseto wrote: > ROTFLOL....you are the one who need to learn SR....what you said is an > erroneous assumption of the PoR that every SR observer is in a state > of absolute rest. This is wrong. The rate of two relative clock A and > B is as follows: > 1. A is running fast compared to B. > 2. B is running slow compared to A. Wrong again Seto! Let's be a bit more precise here: Assume that A and B have identical atomic clocks. That means they tick at the same rate. Now let us suppose that A and B have relative motion, such that their velocity with respect to each other, v > 0, and that dv/dt = 0 . "Closing speed" or "Separation speed", if you like. Correcting for any Doppler shift, A measures B's time interval as ∆t_B' = γ ∆t_B and B measures A's time interval as ∆t_A' = γ ∆t_A where ∆t represent a time interval, v is the relative velocity between A and B, and γ = 1/√(1-v^2/c^2) . Therefore, A measures B's time interval to be longer than her own. And B measures A's time interval to be longer than his own.
From: Michael Moroney on 9 May 2010 15:38
kenseto <kenseto(a)erinet.com> writes: >On May 7, 1:56 pm, moro...(a)world.std.spaamtrap.com (Michael Moroney) >wrote: >> Sam Wormley <sworml...(a)gmail.com> writes: >> >On 5/7/10 10:32 AM, Michael Moroney wrote: >> >> My posts are made on the assumption that all GR effects on theGPS >> >> satellites can be simplified to the gravitational well effect of >> >> ~45uS/day and the motion effects of ~7uS/day. >> > GTR covers everything! SR may be more convenient for some calculations >> > but GTR encompasses SR. Both theories need not be applied separately. >> >> I know that. But the satellite in orbit is constantly accelerating, >So why did you treat the GPS clock as inertial and then claim that the >GPS sees the ground clock as 7 us/day slow and from the ground clock >point of view it also sees the GPS as 7 us/day slow?????? If you had read what I wrote after that instead of just ignoring it, you'd see that, for the case of this discussion, I'm simplifying things to the gravitational effects (~38 uS) and SR effects (~7 uS) and treating them as if they were separate effects that can be added. > Do you just >make up stuff as you go along???? No, that's your work. |