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Tags Allais Effect , Dark Flow , relativity , Theory of Relativity

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Old 24th September 2019, 02:29 AM   #441
steenkh
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Originally Posted by Bjarne View Post
Multiple or not, it make no difference.
GPS is NOT a scientific test of GR or SR
Wrong. GPS would not work at all without SR. The accuracy is within 15m, but without SR, the error would be 10km per day since the synchronization was done.

See for instance this article by Richard W. Pogge:
Originally Posted by Real-World Relativity: The GPS Navigation System
The combination of these two relativistic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)! This sounds small, but the high-precision required of the GPS system requires nanosecond accuracy, and 38 microseconds is 38,000 nanoseconds. If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes, and errors in global positions would continue to accumulate at a rate of about 10 kilometers each day! The whole system would be utterly worthless for navigation in a very short time.
My emphasis.
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Old 24th September 2019, 03:12 AM   #442
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Well, I was somewhat wrong. Pogge's article makes an error in thinking that our clocks need to synchronize with the satellites. Actually, the we need to know the time difference between the satellites, which is much smaller.

I found this comment by "gnasher" to be quite helpful:
Quote:
The problem is that while the clocks are indeed off by 38 microseconds per day and General Relativity is all fine, we wouldn't actually have to compensate for it. The GPS in your car or your phone doesn't have an atomic clock. It doesn't have any clock precise enough to help with GPS. It doesn't measure how long the signal took to get from satellite A to GPS. It measures the difference between the signal from satellite A and the signal from satellite B (and two more satellites). This works if the clocks are fast: As long as they are all fast by the exact same amounts, we still get the right results.

That is, almost. Satellites don't stand still. So if we rely on a clock that is 38 microseconds fast per day, we do the calculations based on the position of a satellite that is off by 38 microseconds per day. So the error is not (speed of light times 38 microseconds times days), it is (speed of satellite times 38 microseconds times day). This is about 15 cm per day. Well, satellite positions get corrected once a week. I hope nobody thinks we could predict the position of a satellite for long time without any error.
gnasher goes on to point out that this compensation of 38 microseconds per day is not be fixed because of the variables speed of the satellites due to the shape of the Earth, gravity variations and so on.

In any case, it is still a fact that knowledge of relativity is necessary for the operation of global positioning systems.
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Old 24th September 2019, 06:45 AM   #443
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Originally Posted by steenkh View Post
Wrong. GPS would not work at all without SR. The accuracy is within 15m, but without SR, the error would be 10km per day since the synchronization was done.

My emphasis.
Think about such a simple thing as the well know influence of
  • perturbation
  • atmospheric drag
  • gravitational crust anomalies,
- it’s a relative large impact, and you have to correct for such influence all the time.

Many times Satellites are even forced regulary back in their original orbits.

Now in addition to that you have other unknown and quantitative uncertainty impact.
These you also have to take into account account for as well, all the time..
Do you really believe that scientist sits and try to figure out all the time if that and this and that was due to that and that, - 100% according to the textbox and theories bla bla bla bla, - and this and this is not according to the book ???.

Notice that it is only few satellites ( following more a less a north south path) that will show relative small anomalies, difficult to discover, and MUCH less as you wrote above.

The smaller your perspective is, the smaller will also anomalies be.
Look at the large scale and you can see there is a hell lot wrong with orbits and our paradigm.

For example take a look at Solar orbits (trajectories) instead or Earth orbits, - and the problems is well known. (Flyby and Pioneer Anomalies) , (filtered for brains death chitchat ')
Now let’s speed a little up, and you have the ʻOumuamua anomaly.

Now again faster we go, and you have HUGE orbit problems. (so-called- Dark Matter)

And again we will speed up and what do you get now. GIGANTIC anomalies even greater as dark matter >>> https://www.youtube.com/watch?v=6OPxKSH3hK4

Everywhere you look up there are HUGE problems, and now you want to use relative slow-moving object to justify that we know EVERYTHING and that NO ANOMALIES, should be expected on the narrow minded level.

How blind is it possible to be ?

https://www.forbes.com/sites/startsw.../#3648c4d84bdc

https://www.youtube.com/watch?v=wb5OGJewPI0

Last edited by Bjarne; 24th September 2019 at 07:02 AM.
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Old 24th September 2019, 07:18 AM   #444
MRC_Hans
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Originally Posted by Bjarne View Post
Think about such a simple thing as the well know influence of
  • perturbation
  • atmospheric drag
  • gravitational crust anomalies,
- it’s a relative large impact, and you have to correct for such influence all the time.

Many times Satellites are even forced regulary back in their original orbits.

*snipped, more mundane chatter*
Yes, yes, Bjarne, we all know launching and maintaining satellites is complex business. But somehow, all the brain-washed, concrete-headed scientists seem to do it quite successfully all the time. Why do you think that is? Could it be that they actually know what they are doing?

And what about it all? GPS would STILL not work if SR was not calculated in and done so correctly.

Quote:
Now let’s speed a little up, and you have the ʻOumuamua anomaly.

Now again faster we go, and you have HUGE orbit problems. (so-called- Dark Matter)
Irrelevant.

And all of it has nothing to do with your "theory". You are just trying to smoke-screen the fact that your so-called theory makes no sense, and that you don't even understand why.

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Old 24th September 2019, 08:10 AM   #445
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Originally Posted by Bjarne View Post
Think about such a simple thing as the well know influence of
  • perturbation
  • atmospheric drag
  • gravitational crust anomalies,
- it’s a relative large impact, and you have to correct for such influence all the time.

Many times Satellites are even forced regulary back in their original orbits.

Now in addition to that you have other unknown and quantitative uncertainty impact.
These you also have to take into account account for as well, all the time..
Do you really believe that scientist sits and try to figure out all the time if that and this and that was due to that and that, - 100% according to the textbox and theories bla bla bla bla, - and this and this is not according to the book ???.

Notice that it is only few satellites ( following more a less a north south path) that will show relative small anomalies, difficult to discover, and MUCH less as you wrote above.

The smaller your perspective is, the smaller will also anomalies be.
Look at the large scale and you can see there is a hell lot wrong with orbits and our paradigm.

For example take a look at Solar orbits (trajectories) instead or Earth orbits, - and the problems is well known. (Flyby and Pioneer Anomalies) , (filtered for brains death chitchat ')
Now let’s speed a little up, and you have the ʻOumuamua anomaly.

Now again faster we go, and you have HUGE orbit problems. (so-called- Dark Matter)

And again we will speed up and what do you get now. GIGANTIC anomalies even greater as dark matter >>> https://www.youtube.com/watch?v=6OPxKSH3hK4

Everywhere you look up there are HUGE problems, and now you want to use relative slow-moving object to justify that we know EVERYTHING and that NO ANOMALIES, should be expected on the narrow minded level.

How blind is it possible to be ?

https://www.forbes.com/sites/startsw.../#3648c4d84bdc

https://www.youtube.com/watch?v=wb5OGJewPI0
Thank you for that stunning example of the Dunning-Kruger effect.
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Old 24th September 2019, 11:58 AM   #446
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Originally Posted by MRC_Hans View Post
Yes, yes, Bjarne, we all know launching and maintaining satellites is complex business. But somehow, all the brain-washed, concrete-headed scientists seem to do it quite successfully all the time. Why do you think that is? Could it be that they actually know what they are doing?

And what about it all? GPS would STILL not work if SR was not calculated in and done so correctly.
Hans
The will work, as I wrote, the SR is such a small effect it is hard to measure, even if we put all we have in play.

Even the ISS I am fare from sure that SR can be measured, and therefore as we saw with the Galileo test, scientist will most likely say: this too was only a GR test , and nothing about SR.
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Old 24th September 2019, 12:06 PM   #447
MRC_Hans
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Originally Posted by Bjarne View Post
The will work, as I wrote, the SR is such a small effect it is hard to measure, even if we put all we have in play.
You wrote that, but you are wrong. SR is a distinct effect that can be measured, and can be verified to comply with the theory.

Quote:
Even the ISS I am fare from sure that SR can be measured, and therefore as we saw with the Galileo test, scientist will most likely say: this too was only a GR test , and nothing about SR.
SR can be measured. If they make it a GR test, it is because that is what they want to test.

Hans
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Old 24th September 2019, 12:39 PM   #448
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Originally Posted by Bjarne View Post
The will work, as I wrote, the SR is such a small effect it is hard to measure, even if we put all we have in play.

Even the ISS I am fare from sure that SR can be measured, and therefore as we saw with the Galileo test, scientist will most likely say: this too was only a GR test , and nothing about SR.
Why are you unsure it can be measured? The math is simple, you can figure out what is predicted and you can google up some atomic clock info to see if they're accurate enough to measure that (they are).
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Old 24th September 2019, 12:47 PM   #449
halleyscomet
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The Theory of Relativity will begin to fall apart in 2016/2017 - Part III

Originally Posted by Bjarne View Post
The will work, as I wrote, the SR is such a small effect it is hard to measure, even if we put all we have in play.

Even the ISS I am fare from sure that SR can be measured, and therefore as we saw with the Galileo test, scientist will most likely say: this too was only a GR test , and nothing about SR.
Have you published any more papers?

Do you have any evidence of your claims aside from insults and your own personal incredulity?

Have you ever convinced ANYONE you were right?

Do you have any goals here other than lobbing insults at people?

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Old 24th September 2019, 01:06 PM   #450
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Originally Posted by Bjarne View Post
The will work, as I wrote, the SR is such a small effect it is hard to measure, even if we put all we have in play.

Even the ISS I am fare from sure that SR can be measured, and therefore as we saw with the Galileo test, scientist will most likely say: this too was only a GR test , and nothing about SR.
Yawn. If I had a pound for every time I've had to link cranks to the following, I'd be a rich man!


General Relativity in the Global Positioning System
Neil Ashby, University of Colorado
http://www.leapsecond.com/history/Ashby-Relativity.htm

The main thing to take away from that, is the following paragraph;

Quote:
At the time of launch of the first NTS-2 satellite (June 1977), which contained the first Cesium clock to be placed in orbit, there were some who doubted that relativistic effects were real. A frequency synthesizer was built into the satellite clock system so that after launch, if in fact the rate of the clock in its final orbit was that predicted by GR, then the synthesizer could be turned on bringing the clock to the coordinate rate necessary for operation. The atomic clock was first operated for about 20 days to measure its clock rate before turning on the synthesizer. The frequency measured during that interval was +442.5 parts in 1012 faster than clocks on the ground; if left uncorrected this would have resulted in timing errors of about 38,000 nanoseconds per day. The difference between predicted and measured values of the frequency shift was only 3.97 parts in 1012, well within the accuracy capabilities of the orbiting clock. This then gave about a 1% validation of the combined motional and gravitational shifts for a clock at 4.2 earth radii.
My highlighting and bolding.

So, using GR and SR the dumb scientists had predicted the time dilation to within 1% prior to launch! In 1977.
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Old 24th September 2019, 03:15 PM   #451
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Exclamation A delusion that his ignorant imagination ("Think about..." ) is the real world

Originally Posted by Bjarne View Post
Think about such a simple thing as the well know influence of ...
25 September 2019 Bjarne: A delusion that his ignorant imagination ("Think about..." ) is the real world !

This is a delusion that the GPS satellite designers do not know about satellites and what affects them . For example, GPS satellites are placed in medium height orbits of ~20,000 km so that there is no significant atmospheric drag and no need to adjust orbits for drag. Compare this to the IIS at 408 km which does need adjustments for drag.
Satellite orbital position errors, induced by variations in the gravity field and radar refraction among others, had to be resolved and were - in the 1970's.

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Old 24th September 2019, 03:18 PM   #452
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Thumbs down Usual "Pioneer Anomalies" lie and "brains death chitchat" insanity

Originally Posted by Bjarne View Post
For example take a look at Solar orbits (trajectories) instead or Earth orbits, - and the problems is well known. (Flyby and Pioneer Anomalies) , (filtered for brains death chitchat ')...
25 September 2019 Bjarne:Usual "Pioneer Anomalies" lie and "brains death chitchat" insanity
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Old 24th September 2019, 03:20 PM   #453
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Thumbs down An abysmally ignorant "'Oumuamua anomaly" related to the flyby anomaly delusion

Originally Posted by Bjarne View Post
...Now let’s speed a little up, and you have the ʻOumuamua anomaly.
25 September 2019 Bjarne: An abysmally ignorant "'Oumuamua anomaly" related to the flyby anomaly delusion - 'Oumuamua did not fly by the Earth !
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Old 24th September 2019, 03:33 PM   #454
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Thumbs down Idiotic lies about dark matter - dark matter is the name and it is not a problem

Originally Posted by Bjarne View Post
Now again faster we go, and you have HUGE orbit problems. (so-called- Dark Matter)
25 September 2019 Bjarne: Idiotic lies about dark matter - dark matter is the name and it is not a problem (it solves many problems!).

Dark matter is called dark matter because there is no evidence that it emits light or interacts electromagnetically. It is called dark matter because it acts like matter. Galaxy rotation curves show that there is matter in galaxies that is not visible matter. Colliding galaxy clusters show matter separating into visible matter and dark matter. The CMB cannot be explained without non-baryonic matter (dark matter). The large scale structure of the universe cannot be explained without dark matter.

There are small, known problems with dark matter that have possible solutions, e.g. the cusp problem (models show a sharp density increase in galaxy centers, data says no) may be solved if dark matter has interactions.
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Old 24th September 2019, 03:41 PM   #455
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Exclamation A delusion that alignment of quasar rotation axes are to do with his delusions

Originally Posted by Bjarne View Post
And again we will speed up and what do you get now. GIGANTIC anomalies even greater as dark matter
25 September 2019 Bjarne: A delusion that alignment of quasar rotation axes is anything to do with his delusions.

This is the stupidity from many cranks that problems with working science somehow support their ignorant delusions.

In 2014, astronomers found that quasars that were separated by billions of light years were parallel to each other and tended to be aligned with their containing structures. This is real science.
Alignment of quasar polarizations with large-scale structures
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Old 24th September 2019, 03:47 PM   #456
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Thumbs down An "Everywhere you look up there are HUGE problems" lie and delusion

Originally Posted by Bjarne View Post
Everywhere you look up there are HUGE problems, ...
25 September 2019 Bjarne: An "Everywhere you look up there are HUGE problems" lie and delusion.

Everywhere we look there are HUGE, SOLVED problems. There are actual unsolved problems in astronomy, e.g. the evidence is overwhelming that dark matter is non-baryonic particles but what are those particles?

The delusion is the usual crank one that problems in mainstream science supports their delusions. Where is Bjarne's math and physics that solves his imagined "HUGE problems"?
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Old 24th September 2019, 03:55 PM   #457
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Exclamation Lies about GPS satellites by citing a general satellite source

Originally Posted by Bjarne View Post
25 September 2019 Bjarne: Lies about GPS satellites by citing a general satellite source that says he is lying !

Why Are Earth-Orbiting Satellites Fundamentally Unstable?
Quote:
1.) Atmospheric drag. This is by far the biggest effect, and this is the reason that low-Earth orbits are so unstable. Other satellites -- like geosynchronous satellites -- will decay as well, but not on such short timescales. ... This is why low-Earth orbit satellites are so unstable.
GPS satellites are not low-Earth orbit satellites !
The rest are all factors that GPS designers know about and account for.
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Old 24th September 2019, 04:07 PM   #458
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Exclamation Gibberish about scientists testing GR in experiments obviously not testing SR

Originally Posted by Bjarne View Post
The will work,...
25 September 2019 Bjarne: Gibberish about scientists testing GR in experiments obviously not testing SR!

We have been testing SR for 114 years. SR has small to enormous effects that are easy to measure.
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Old 25th September 2019, 06:32 PM   #459
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Originally Posted by Elagabalus View Post
I noticed that you did not answer my question.
Do you mean this one?

Originally Posted by SDG View Post
Originally Posted by Elagabalus View Post
Did you watch the video I gave you about the twin paradox?
Yes,
SDG
I did,
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Old 25th September 2019, 07:20 PM   #460
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Originally Posted by Robin View Post
So, in effect, you have added two events, the first in the platform frame:, "Something happens at the start of the rod at the same time as the light reaches the end of the rod" and the second event in the train frame "Something happens in the middle of the train at the same time as the light reaches the end of the rod. Then you are doing a Lorentz transform on the first event and using that time as the time for the second event and doing a second transform. Naturally neither of these transforms will have the x term. Is that a fair description of your calculation?
Yes, correct.
Einstein started his 1905 paper with a couple of pages describing synchronization and describing a grid of inertial observers with synchronized clocks.
For example there are three observers on the train: a conductor in the middle, a left end (LE) train car observer and a right end (RE) train car observer.
We assume they have synchronized clocks. When the conductor sends the beams left and right at t'=0 then it follows that LE observer has t'=0 on his clock and RE observer has t'=0 on his clock at the same simultaneity moment.
The clock could be a local 1mm cavity where a light beam bounces left and right and the local observer counts the cycles, a simple local light clocks.
When we say the conductor sees the light hit the LE or RE of the train car at a specific time it means the light travelled the half of the train car length at this time. This distance will be equal in all local light clocks.
The important point is that the conductor does not know when it happens. The conductor has to wait for the light to reflect and to come back, the full round trip of the light.
The time of the reflection is defined as 1/2 of the full round trip time as per Poincaré and Einstein agreed with him.
This is just a definition, there is no experiment that proves one way speed of light/time in reality.
The isotropy of the one way light speed is a postulate, not tested.
I showed through the thought experiment that the isotropy of the one way light speed cannot be true.
If people cannot see it maybe my next post will help.
SDG

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Old 25th September 2019, 07:44 PM   #461
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Another modification of our thought experiment, now to the left.



There is a green rod 5.5cs long and at t=t'=0 the platform observer at x=0 sends a green light beam to the left.

At 5 seconds of the platform time.



And the space time diagram.



The grid of platform inertial observers is going to see the platform green rod end hit at 5.5s.
The question: at what time of the train proper time is the grid of the train inertial observers going to see the hit of the platform green rod end?
SDG

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Old 25th September 2019, 07:53 PM   #462
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Originally Posted by SDG View Post
Yes, correct.
The trouble is, that doesn't make sense mathematically.

If you do a LT from frame A to frame B with x=0 then you can't do an LT from frame B to frame A using the time value you got from the first LT and x=0 and expect to get back the original value for t. You have to also use the x value from the first LT.

Quote:
I showed through the thought experiment that the isotropy of the one way light speed cannot be true.
If people cannot see it maybe my next post will help.
SDG
Similar problem with the thought experiment.

I can see you do a LT from the train frame to the platform frame using t=5.20 but then you transform the time back from the platform frame to the train frame using x= 0 and naturally you get back a different value for t.

That is not any sort of contradiction.
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Old 25th September 2019, 07:59 PM   #463
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Originally Posted by Robin View Post
Which doesn't make sense because a transform on x=0 will not map to x'=0 unless t=0 or v=0.

So you if you do a transform from the platform frame to the train frame at x=0, you can't then do a transform from the train frame back to the platform frame with x=0 and claim that it should be mapping back to the original time.
There is nothing wrong to ask what time is on the clock at x'=0 of the other frame.
What answer will LT give us?
SDG
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Old 25th September 2019, 08:04 PM   #464
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Thumbs down A "...isotropy of the one way light speed cannot be true" lie

Originally Posted by SDG View Post
Einstein started his 1905 paper with a couple of pages describing synchronization and describing a grid of inertial observers with synchronized clocks.
For example there are three observers on the train:...I showed through the thought experiment that the isotropy of the one way light speed cannot be true.
The description of the start of Einstein's paper is correct. But then you end with:
26 September 2019 SDG: A "I showed through the thought experiment that the isotropy of the one way light speed cannot be true" lie.

The "thought experiments" that you keep coming up show a persistent ignorance of concepts of physics such as the Lorentz transformation. Your opinion about these does not show anything about any physics.

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Old 25th September 2019, 08:06 PM   #465
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Originally Posted by Myriad View Post
You haven't defined any events on the x=0 or x'=0 world lines, except for the initial light flash at t=t'=0.

Claims about the timing of events that you haven't defined cannot be evaluated. You are trying to take advantage of your own lack of clarity to give you wiggle room to claim a contradiction where there is none.

The thought experiment you pasted from a textbook defines its relevant events (the emission of the light pulse at the near side of the carriage, the arrival/reflection of the light pulse at the far side of the carriage, and the detection of the light pulse at the near side of the carriage again). That specificity makes the ensuing calculations possible. Your thought experiment, so far, lacks that specificity.

My post #349 completely describes the physics of your thought experiment as you've presented it so far. If you want to do calculations concerning additional events on the x=0 or x'=0 world lines, then you need to define some additional events on the x=0 or x'=0 world lines.
Really? What is different between the two bold parts in describing the thought experiments.
I did exactly the same thing as the text book. My thought experiment is clearly described.
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Old 25th September 2019, 08:15 PM   #466
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Originally Posted by Robin View Post
The trouble is, that doesn't make sense mathematically.

If you do a LT from frame A to frame B with x=0 then you can't do an LT from frame B to frame A using the time value you got from the first LT and x=0 and expect to get back the original value for t. You have to also use the x value from the first LT.


Similar problem with the thought experiment.

I can see you do a LT from the train frame to the platform frame using t=5.20 but then you transform the time back from the platform frame to the train frame using x= 0 and naturally you get back a different value for t.

That is not any sort of contradiction.
Are you saying that there is a mistake here?

Platform half the train car length contracted: L=6cs
Proper length: L'=gamma * 6cs=6.1237243569cs
One-way light proper time on the train: t'=6.1237243569s
Proper platform time for t' (time dilation): t=gamma * t'=6.25s

Where?
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Old 25th September 2019, 08:15 PM   #467
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Thumbs down An irrelevant question about an ever changing thought experiment to waste our time

Originally Posted by SDG View Post
Another modification of our thought experiment, now to the left....
The question:
26 September 2019 SDG: An irrelevant question about an ever changing thought experiment to waste our time yet again.

You are the one who has a claim that SR is wrong. You must know SR to have that claim.
Weeks (first post here on 24th August 2019) of changing a thought experiment and asking questions is wasting our time. Either you know SR and thus the answer. Or you are arguing from ignorance, refusing to learn and will repeat updating the experiment and asking questions forever - also a waste of our time.
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Old 25th September 2019, 08:19 PM   #468
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Originally Posted by SDG View Post
There is nothing wrong to ask what time is on the clock at x'=0 of the other frame.

What answer will LT give us?

SDG
I didn't say there was anything wrong with asking what the time on the clock is at x=0 in the other frame.

Expecting it to be the same as the time you used for the original LT does not make sense, mathematically.
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Old 25th September 2019, 08:23 PM   #469
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Originally Posted by Robin View Post
I didn't say there was anything wrong with asking what the time on the clock is at x=0 in the other frame.

Expecting it to be the same as the time you used for the original LT does not make sense, mathematically.
Do you agree that the reciprocity is real and two inertial observers do not agree on their respective proper time intervals?
In other words they do not agree who is aging faster...
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Old 25th September 2019, 08:26 PM   #470
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Exclamation A dumb question when the post he replied to states the mistake

Originally Posted by SDG View Post
Are you saying that there is a mistake here?...
26 September 2019 SDG: A dumb question when the post he replied to states the mistake !

For others:
The Lorentz transformation cannot be applied in 1 frame of reference and then applied in another frame of reference to the value from the first frame.
Let there be two inertial observers Alice and Bob with clocks. This is the Lorentz transformation. Let Alice have the "primed frame". Alice measures a time dilated interval for Bob's clock. Alice cannot magically make herself Bob in his frame and input that interval into the LT to get another interval.
The reason that inertial is emphasized is that Alice can accelerate to match Bob's frame. t then the transformation is trivial - plug a speed of 0 into the LT.
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Old 25th September 2019, 08:26 PM   #471
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Originally Posted by SDG View Post
Do you mean this one?



I did,
SDG
This one.

Originally Posted by Elagabalus View Post
Dude, are you a flat earther? I'm starting to get that vibe.
Apologies if you aren't but you sure act like it.
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Old 25th September 2019, 08:34 PM   #472
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Originally Posted by SDG View Post
Are you saying that there is a mistake here?



Platform half the train car length contracted: L=6cs

Proper length: L'=gamma * 6cs=6.1237243569cs

One-way light proper time on the train: t'=6.1237243569s
Clarify, for what event?
[/quote]
The light reaching the front of the train?

Do the complete LT and tell me what value for x' you get.

Now do another LT from train back to platform using t=6.1237243569s and the new x value and v=-c/5 and tell me what time you get.
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Old 25th September 2019, 08:34 PM   #473
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Originally Posted by Elagabalus View Post
This one.



Apologies if you aren't but you sure act like it.
I am not. What gave you that impression?
Why are you apologizing?
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Old 25th September 2019, 08:35 PM   #474
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Thumbs down Ignorant "reciprocity" and "proper time intervals" questions about textbook SR

Originally Posted by SDG View Post
Do you agree that the reciprocity is real and two inertial observers do not agree on their respective proper time intervals?
26 September 2019 SDG: Ignorant "reciprocity" and "proper time intervals" questions about textbook SR.

The Lorentz transformation involves speed so transformed quantities must be reciprocal between inertial frames.
Two observers agree on proper time intervals in SR by definition!

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Old 25th September 2019, 08:43 PM   #475
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Exclamation More ignorance - proper length is a length in the frame, i.e. L or L'

Originally Posted by SDG View Post
...Proper length: L'=gamma * 6cs=6.1237243569
26 September 2019 SDG: More ignorance - proper length is a length measured in the frame, i.e. L or L' by definition.

If an object has a length L in its frame and anyone gets a proper length that is not L they immediately know that they have gone extremely wrong somewhere in their application of physics.
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Old 25th September 2019, 08:45 PM   #476
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Originally Posted by Robin View Post
Clarify, for what event?

The light reaching the front of the train?

Do the complete LT and tell me what value for x' you get.

Now do another LT from train back to platform using t=6.1237243569s and the new x value and v=-c/5 and tell me what time you get.
Please, check the post #238 and let me know if it answers your questions.

Going back:
The contracted rod as seen from the train frame: Lrod=6.1237243569cs
Proper length in the platform frame: L'rod=gamma * 6.1237243569cs = 6.25cs
One-way light proper time in the platform frame: t'=6.25s
Proper train time for t' (time dilation): t=gamma * t'=6.3788795384s
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Old 25th September 2019, 08:47 PM   #477
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SDG

Basically you are saying that t=6.1237243569s maps to a different time on the platform if x=0 then it does if x=6.1237243569s.

Yes?
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Old 25th September 2019, 09:01 PM   #478
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Originally Posted by Robin View Post
SDG

Basically you are saying that t=6.1237243569s maps to a different time on the platform if x=0 then it does if x=6.1237243569s.

Yes?


If we look at the right side space time diagram. That's the train frame view.
The relativity of simultaneity says that t'=6.25s of the platform time is supposed to be train time of t=6.1237s.
The time dilation says that t'=6.25s of the platform time is supposed to be train time of t=6.3788s.
If you think about an answer to the post #461 the problem might be more visible.
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Old 25th September 2019, 09:15 PM   #479
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Originally Posted by SDG View Post
I am not. What gave you that impression?
Your insistence that SR is wrong to the exclusion of all else. Plus 114 years of Physics has not overturned it.

Originally Posted by SDG View Post
Why are you apologizing?

So I don't run afoul of the mods.

So some sort of EUer if only weakly so?
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Old 25th September 2019, 09:22 PM   #480
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Originally Posted by Robin View Post
SDG

Basically you are saying that t=6.1237243569s maps to a different time on the platform if x=0 then it does if x=6.1237243569s.

Yes?
Here is the math answer:


Time t is defined by the left side, time dilation.

Time t is defined by the right side as t=t'/gamma + (v/c^2)x, the simultaneity.

We have two equations for t, which on is correct?
... and they give two different t values for one t'.
... therefore the contradiction.
SDG

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