Absolute Velocity of Inertial Frames Using Time Signatures in Message Exchanges

[Pete]

unless the light was aimed that way

Well, I imagine that the experiment is set up so that the light source is seen at the detector. But, you should also ask yourself precisely how much is the distance involved, and whether it would actually require a any adjustment.

I understand that MM probably aimed the light as you describe in order to assure that variations in relative velocity could be measured by fringe shifts, but this is a flaw in the experimental arrangement.

It might be a flaw if the experiment were naively performed as it is described in popular literature, but (believe it or not) experimental physicists are a little smarter and more rigorous than that. Perhaps you could read some of the original publications on this type of experiment? start with those listed here.

Pete. Will, in your expert opinion, the mutual adoption of the pulsar-tick-scheme work to synchronize the two tick rates here, at the very least?

1. I'm not an expert.
2. The best that could be achieved is synchronizing the clocks in the pulsar's rest frame, ie this would establish the pulsar as are zero-velocity reference.

Some one (an SRTist) used the "dragged along" argument in a discussion a few years ago - similar topic.

I suggest that either they were wrong, or that you misremember the argument.

I do not see a "zero velocity standard" from what you just said.

Nevertheless, there it is. Clocks that are synchronized are only synchronized with respect to a particular zero-velocity reference.

I do see it in the(X0,t0) as the point is not moving.it is an invariant point in a 3-dimensional universe.
...
An abstract point in space that emitted light once, is "physically impossible to move." This is not a mind bending concept.

You are confused about acceleration and and movement. I am describing abstractions that are locatable and identifiable [by location], that is , (X0,To).

This invariant point is a figment of your imagination. It does not appear to exist in reality.
A point in space is neither locatable nor identifiable, except in reference to some physical object which is can be used as an arbitrary velocity reference.

when I learned of that which you speak and then spent a number of years unlearning silliness.

Geistkiesel, you've demonstrated over and over and over that you have never learned what AN is talking about. You clearly have no idea of the basic concepts. Please, go and learn. It's not that hard.
And you don't need to agree with it, but you do need to understand it if you want to engage in meaningful discussion about it.

 

[Pete]

I am aware of the technique of aiming a torch, or flashlight, but how does velocity get into the equation as determining the direction of the light?

A pulse of light from a flashlight (or laser, or torch, or collimated light source) that is aimed North and moving West will travel at c in a North-Westerly direction. The higher the light source's westward speed, the greater the westward angle of the light pulse.

From Relativistic Abberation:

Look at this animation. It shows a pulse of light, which we imagine we can see, travelling to a camera from the far corner of a box moving at close to light speed.
Quicktime Movie
The light pulse has come from the back corner of the box, which we would expect to be obscured by the box itself. But the box is moving fast enough that it gets out of the way of the light pulse. This is possible because the light is moving directly towards the camera, while most of the box's movement is perpendicular to the light's path. ​

 

[James R]

[blah blah blah snip] Therefore, A and B knowing Vab, the relative AB relative velocity. Vab, and when expressed as Va – Vb, then Vb = Va – Vab.
And Humpty is back together again.

So, Humpty has determined the relative speed of A relative to B.

Humpty still doesn't know anything about the absolute speeds of A or B.

i.e. your thread is pointless, as usual.

 

[draqon]

what if relative speeds of every object were to be measured in the universe, relative velocities as well as time they traveled those velocities, wouldnt including everything in the universe tell us about the absolute speeds as well

 

[James R]

what if relative speeds of every object were to be measured in the universe, relative velocities as well as time they traveled those velocities, wouldnt including everything in the universe tell us about the absolute speeds as well

No.

 

[draqon]

No.

why not? knowing velocities of every object will make it obsolete

 

[James R]

Knowing relative velocities will never tell you an absolute velocity. That's geistkiesel's elementary mistake.

 

[draqon]

Knowing relative velocities will never tell you an absolute velocity. That's geistkiesel's elementary mistake.

whats absolute velocity than? absolute to what inertial frame?

 

[AlphaNumeric]

Everything you have offered here is, in scientific terms, bullshit. You don't even know how to insult, are you Lituanian, perhaps?

I didn't reply with anything scientific because you haven't said anything which warrants that. I am capable of talking and doing extremely complicated stuff but when typing it on a forum it is a lot of effort and since its obvious such effort would be wasted on you I don't bother.

If you're so sure, why don't you type up your work, submit it to a journal, get praised as the man who revealed the truth about physics and then you can have that dinner with Hawking without needing anyone to facilitate it. Could it be because you have nothing but whining?

And I can't tell if you calling me Lithuanian was a very very pathetic attempt at an insult or you're being ironic. Why the hell should I care about being Lithuanian?

I was older than the eighteen year olds who with hangovers and less than 3 hours of sleep can grasp etc…. when I learned of that which you speak and then spent a number of years unlearning silliness.

Oh, so you used to know all this stuff but now you don't. And now you make elementary errors because you've forgetten things you now actually need to use? Oh well that's okay, that's quite different from you never knowing and being too stupid to learn.

AN are you telling us that when your SRT profs told you that ‘ you must divest yourself of notions of logic, reason and appearances, that you must unlearn what you believed, that you had no clue you were taken for a ride? Is this your story? If so it is one of , if not the saddest tale of heartbreak, disappointment and despair I have ever heard. I bet they even told you that, “Nobody, but nobody gets to see the Wizard”. I was going to take you to lunch and introduce you to her, but if that’s your attitude, O.K..

Where did I say that? Rather than spending your time inventing imaginative but fictional narratives for the life stories of people you don't know why don't you (re)learn the mathematics of special relativity so that you can clearly and concisely show how it's wrong. If you know there's a mistake in the mathematical methods then why don't you correct it and publish a paper on it?

If cranks were right they'd not be on forums. Even the people who are considered on the fringe of mainstream science don't publish on forums, they put work on ArXiv and/or publish in journals, having submitted their work to peer review and listened to the reviewer. You whine about how the application of Gauss's theorem isn't appropriate to Newtonian physics but you can't show by how much.

For instance, if you knew general relativity, which inherently includes the finite speed of light and gravity propogation you'd know that when you solve the Einstein Field Equations for a spherically symmetric shell or ball of material the resultant metricoutside the object is precisely the Schwarzchild metric, the same metric you get from a point mass. If the Sun collapsed into a black hole right now the path of the Earth would not change because the gravitational field would only change in the region which is currently beneath the surface of the Sun.

Your ignorance of GR has meant you've wasted time whining about how Newton's Shell Theorem doesn't include the finite speed of gravity while the extension of Newtonian gravity which does include it gives precisely the same answer. Collapsing spheres of material and the gravitational fields they produce are the stuff of homework problems.

Hence why I believe you never learnt this stuff and then unlearnt it, because if you had you'd be aware the problem you whine about is not a problem at all.

I'd reply to the rest of your post but I have to drive across the country and don't have the time....

 

[phyti]

pete;
post 49:

- The light is not "dragged along by the frame". The direction in which the light travels is set when it is emitted, depends on the velocity of the source.

Here's more to consider.
If the emitter has different relative speeds for different observers,
and the absolute speed is unknown, which speed determines the angle of
emission?

 

[Pete]

If the emitter has different relative speeds for different observers,
and the absolute speed is unknown, which speed determines the angle of
emission?

The relative speed. Just as in Galileo's relativity for low speed projectiles. The direction of a projectile is relative, not absolute.

Imagine you're driving along a straight road.
You see a motorist traveling in the opposite direction toss an apple core out the window.

Now, imagine that this scenario is filmed by three different overhead cameras (all oriented the same way, looking straight down with North at the top of the viewfinder):
1 - The first camera tracks the ground. (eg a particular roadsign is always in the centre of the viewfinder).
2 - The second camera tracks the second motorist. (The second vehicle is always in the centre of the viewfinder).
3 - The third camera tracks you. (Your vehicle is always in the centre of the viewfinder).

Each camera records a different angle for the apple's trajectory. If you know the various velocities (relative to the ground), then you can figure out the various angles.

The three cameras made three true records of a single situation. The difference is in their rest references. So we see that the angle of the apple's trajectory is relative to the chosen rest reference. There is no single "true" angle.

 

[geistkiesel]

A recap of the thread.

The initial arrangement was two inertial frame approaching each other on a line with a relative velocity of Vab = Va – Vb, where the task is to determine Va and Vb each, which I define as the “absolute velocity” of the A and B frames. Each frame has automatic response transponders, which are radar devices where the echo from a ground station pulse is a triggered time with received signal instead of a reflected signal.

At the start A sends a time encoded pulse with the message, “Emitted @ t0”

B receives the signal and replies, “rec’d/emitted @ t1”

A receives the signal and replies, “rec’d/emitted @ t2”

B receives the signal and replies, “rec’d/emitted @ t4”

The A to B instantaneous distances are “

A to B: c(t1 – t0)
B to A: c(t2 – t1)

The total distance from t2 – t0 is known by A’s exclusive information., as is t3 – t1 [where c =1]/\.

When A uses the B supplied information of t1, A then may determine the distance traveled from during t2 – t0 and therefore can calculate the A frame velocity, Va and Vb follows in step.

I have accomplished the task I started on, which was to see if a system could be devised whereby the absolute velocity of inertial frames moving wrt each other could be determined. D1 = t1 – t0
D2 = t2 – t1
[D1 – D2]/[t2 – t 0] = Va. QED.

What has followed is a detailed discussion regarding the scientific integrity of the data point, t1. The clocks on A and B had been synchronized at the same instant from the same ‘clock trigger’ which starts the A and B clocks ticking; where the frames were moving anti-parallel wrt each other; where after taking mirror image horseshoe
trajectories are now heading toward each other and attempting to perform the experiment again.

What if the frame clocks weren’t synchronized? Can the frames determine their respective Va and Vb by an exchange of information?

A knows t2 = t0 from the A frame clock. B knows t3 = t1 from the B clock. A at first knows nothing regarding t1. To narrow the problem the A and B frame use km, meters, hours, seconds as learned on earth, for instance.

A sends a message, “t2 – t0 = t20” If A was at rest wrt B, actually, the value t1 value is restricted to t1 > 6 (and this without regard to differences in the A/B clock-tick-rate (CTR). Both frames have agreed to synch their clocks initially to the A clock. (Keep in mind B is doing the same and each swaps their t3 – t1 and t2 – t0 times.

Setting pulse rate:
PulsarX CTR: The A and B frame agree to use the pulsed time of PulsarX (PX). Each agrees that the control cabin (cockpit) to tail direction is “North to South” with the E and W being individual frame dependent using earth protocols. For instance B says, “Am using PX on my SES quadrant”, A responds “PX on my NWN quadrant”. There is an agreed CTR with a slight ‘doppler’ error built in: B’s delta CTR > A’s delta CTR. Given enough time even this difference can be corrected for.

Self generated common CTR:
A sends out a constant CTR to which the B frame calibrates his CTR. As the frames approach each other and when directly opposite, the increase in CTR that B measures will reach a peak and then begin to decay. B agrees to use the peak CTR, which should be the same as the A CTR. If the frames are close enough, a common time-of-day can be established.

Now when the t1 data point is emitted the clocks on both frames are synchronized. Even if the time dilation of B before calibration, once b begins using the calibrated CTR and TOD as used by A, if A and B have both agreed that Vb = X2 where before calibration Vb = X1, B will, for instance, be able to navigate back to earth in a rational and reasonable manner despite using a CTR different than its velocity would seem to dictate.

The discussion in the thread has developed into a defense of SRT which was not under attack. Even if the A and B frames were able to determine their absolute velocities, SRT would not immediately die, or even need any therapeutic treatment. SRT and NonSRT are simply two forms of describing what is seen or observed. To be sure philosophical and technical differences run deep, and have the appearance of reflecting heated religious differences. Remembering that what is science today was the religious science of the past. There was never a break as much as a move away from a religious mode , where not only did the religious powers that be determine physical reality, the church was also the judge of any variations sought to be imposed – just ask Galileo, and of course, Giovanni Bruno. My primary complaint with SRT isn’t SRT, it is the preaching by some that demand recognition that SRT is an accurate (mostly only) reflection of physical law. One small example will describes it. A few year two astronomers reported (and which was reported in the pedestrian press) a measurement of the ‘speed of gravity’. A reply indicated the measurement was only of the, ‘speed of light’. I mention in a post Tom Van Flandern’s theses that the speed of gravity forces, even from Newton’s time, had to be > 2x10^10c – you know, ‘action at a distance’. No one in this forum has challenged Flandern on that point – but they do throw unnice things at Flandern. Flandern makes the point clear, that solar system (he differentiates between gravity force and gravity waves) we see now in a state of relative equilibrium would be unrecognizable if the forces of gravity were as slow as the SOL. Search on the “speed of gravity” you will get a lot more, on both sides of the story. Carlip, btw, did not falsify Flandern.

 

[geistkiesel]

So, Humpty has determined the relative speed of A relative to B.

Humpty still doesn't know anything about the absolute speeds of A or B.

i.e. your thread is pointless, as usual.

If t1 is a synchronized value, i.e. if t1 in the B frame and t1 in the A frame are the same and the tick rates of easch clock are the same, then Va has been determined from (d1 - d2)/(t2 - t0). This is the Va in the Vab = Va - Vb expression. What is so confusing to you ?

 

[geistkiesel]

The relative speed. Just as in Galileo's relativity for low speed projectiles. The direction of a projectile is relative, not absolute.

Imagine you're driving along a straight road.
You see a motorist traveling in the opposite direction toss an apple core out the window.

Now, imagine that this scenario is filmed by three different overhead cameras (all oriented the same way, looking straight down with North at the top of the viewfinder):
1 - The first camera tracks the ground. (eg a particular roadsign is always in the centre of the viewfinder).
2 - The second camera tracks the second motorist. (The second vehicle is always in the centre of the viewfinder).
3 - The third camera tracks you. (Your vehicle is always in the centre of the viewfinder).

Each camera records a different angle for the apple's trajectory. If you know the various velocities (relative to the ground), then you can figure out the various angles.

The three cameras made three true records of a single situation. The difference is in their rest references. So we see that the angle of the apple's trajectory is relative to the chosen rest reference. There is no single "true" angle.

A person drops an apple from the window of a moving train. The apple follows a aline of vertically oriented rivets exactly. The train observer sees the apple fall and sees the apple approaching the ground. A ground observer sees the apple falling along the same line of rivets and sees the apple taking a curved path wrt the embankment - he sees both frames of reference. The train observer can also determine the curved trajectory wrt the embankment.

If the apple is a ball, a tennis ball, and the ground bext to the train is similar to a tennios racket oriented horizontally, which way will the ball bounce if:

The ground is actually the accelerated frame, now moving inertially?

The train is the accelerated frame moving inertially?

WRT the ground the ball would be directed in the same direction as the ground is moving in order that the balle be given the ground momentum. If the train is moving, the ball has the train momentum and therefore will bounce straight back up with slight forward losses from friction.

Is this another instance of determining actual velocity vs theoretical velocity.

 

[geistkiesel]

The relative speed. Just as in Galileo's relativity for low speed projectiles. The direction of a projectile is relative, not absolute.

Imagine you're driving along a straight road.
You see a motorist traveling in the opposite direction toss an apple core out the window.

Now, imagine that this scenario is filmed by three different overhead cameras (all oriented the same way, looking straight down with North at the top of the viewfinder):
1 - The first camera tracks the ground. (eg a particular roadsign is always in the centre of the viewfinder).
2 - The second camera tracks the second motorist. (The second vehicle is always in the centre of the viewfinder).
3 - The third camera tracks you. (Your vehicle is always in the centre of the viewfinder).

Each camera records a different angle for the apple's trajectory. If you know the various velocities (relative to the ground), then you can figure out the various angles.

The three cameras made three true records of a single situation. The difference is in their rest references. So we see that the angle of the apple's trajectory is relative to the chosen rest reference. There is no single "true" angle.

You have just explained what 'tautology' is in very clear language.

 

[geistkiesel]

whats absolute velocity than? absolute to what inertial frame?

Take a point on the surface of the earth and use this as an instantaneous determination of from where velocity is measured. You fy into space for 10 years and you begin looking for the point from which your velocity was measured when you return. You return to the place on earth and see no moniument or other markings regarding the signal sent that used . Ah, then you remember, that was 10 years back. You jump back into your space ship make some navigation inputs, launch and head for the point in space where it was when your velocity was set and this point just ain't moving, even in 10 years. All there is of course is empty space, but your navigation system allows you find it, as if it were necessary.

Once you know a velocity you needn't keep referencing from where is the velocity measured. This can always be done.

I say, the instant a pulse is emitted, a point in space that is invariant has been set.

Likewise if the relative velocvity of inertial frames A and B is Vab, then determining Va from information exchanges with B, where Va and Vb are relative to V0 = 0.

 

[geistkiesel]

whats absolute velocity than? absolute to what inertial frame?

Take a point on the surface of the earth and use this as an instantaneous determination of from where velocity is measured. You fy into space for 10 years and you begin looking for the point from which your velocity was measured when you return. You return to the place on earth and see no moniument or other markings regarding the signal sent that used . Ah, then you remember, that was 10 years back. You jump back into your space ship make some navigation inputs, launch and head for the point in space where it was when your velocity was set and this point just ain't moving, even in 10 years. All there is of course is empty space, but your navigation system allows you find it, as if it were necessary.

Once you know a velocity you needn't keep referencing from where is the velocity measured. This can always be done.

I say, the instant a pulse is emitted, a point in space that is invariant has been set.

Likewise if the relative velocvity of inertial frames A and B is Vab, then determining Va from information exchanges with B, where Va and Vb are relative to V0 = 0.

 

[Pete]

I say, the instant a pulse is emitted, a point in space that is invariant has been set.

That's the thread in a nutshell.
You say that absolute space exists.

Once you know a velocity...

...you know a relative velocity. You can't know an absolute velocity. At least, not in any way that you've suggested.

 

[Pete]

A person drops an apple from the window of a moving train. The apple follows a aline of vertically oriented rivets exactly. The train observer sees the apple fall and sees the apple approaching the ground. A ground observer sees the apple falling along the same line of rivets and sees the apple taking a curved path wrt the embankment - he sees both frames of reference. The train observer can also determine the curved trajectory wrt the embankment.

Yes, that's correct. Anyone with intelligence can consider things in multiple reference frames.

If the apple is a ball, a tennis ball, and the ground bext to the train is similar to a tennis racket oriented horizontally, which way will the ball bounce if:

The ground is actually the accelerated frame, now moving inertially?

The train is the accelerated frame moving inertially?

There's no "accelerated frame" here geistkiesel. I'm guessing that you're thinking that historical accelerations are somehow relevant.

WRT the ground the ball would be directed in the same direction as the ground is moving in order that the ball be given the ground momentum.

WRT the ground, the ground is at rest. Not moving. Perhaps you meant WRT the train?

WRT the train, the ball falls straight down, then bounces up and toward the back of the train (ie in the direction the ground is moving), with some backspin.

If the train is moving, the ball has the train momentum and therefore will bounce straight back up with slight forward losses from friction.

WRT the ground, the ball is moving forward (keeping up with the train) as it falls. It bounces up and forward, no longer keeping up with the train, with some backspin.


In both cases, the ball moves closer to the back of the train after the bounce. If the ball marked the wall of the train as it bounced up, it would obviously make the same marks in both cases - we are, after all, talking about exactly the same occurrence, just from two different points of view.

Is this another instance of determining actual velocity vs theoretical velocity.

It appears to be another instance of you having no clue about what "reference frame" even means, and not even trying to understand what it means.

I'm giving up on you, geistkiesel. I've tried to help, but it's useless. Sorry.

 

[AlphaNumeric]

A few year two astronomers reported (and which was reported in the pedestrian press) a measurement of the ‘speed of gravity’. A reply indicated the measurement was only of the, ‘speed of light’. I mention in a post Tom Van Flandern’s theses that the speed of gravity forces, even from Newton’s time, had to be > 2x10^10c – you know, ‘action at a distance’. No one in this forum has challenged Flandern on that point – but they do throw unnice things at Flandern. Flandern makes the point clear, that solar system (he differentiates between gravity force and gravity waves) we see now in a state of relative equilibrium would be unrecognizable if the forces of gravity were as slow as the SOL. Search on the “speed of gravity” you will get a lot more, on both sides of the story. Carlip, btw, did not falsify Flandern.

Flandern's work was debunked a long time ago and I'm pretty sure DH has commented on it in this thread or a previous one of yours.

You claim that the solar system would be quite different if the speed of gravity were to be the speed of light. That is patently wrong since GR says the speed of gravity is the speed of light and GR's description of the solar system is very very accurate. Hence the current configuration and dynamics of the solar system is not evidence for the speed of gravity being massively different from the speed of light.

But then given your ignorance of the GR description of the solar system, such as how spherical objects have the Schwarzchild metric as their local gravitational field configuration thus extending the Shell theorem to finite gravity speed models, its not surprising you yet again reach the wrong conclusion.