Einstein's Special Relativity Fails?

[TeleMad]

TeleMad: 1) Consider what happens if the satellite were to be flying perpendicular to the direction of Earth’s rotation: orbiting from north pole to south pole and back.

 

Mac: We have. Nothing is the answer. The referance point is to the center of the earth remember?

 

Irrelevant, and your method is still flawed, just as I said. Let me explain with a simple example.

 

There's a party, but no beer, and worse, the school's board-1 chess player isn't there (can't have a party without him!). So Alice goes to get beer and Bill goes to get the chess player, while everyone else stays in the dorm. From the dorm, Alice drives due east as 40 mph, so her velocity relative to the dorm is 40 mph due east. From the dorm, Bob drives due north at 30 mph, so his velocity relative to the dorm is 30 mph due north. The dorm stays where it is.

 

Now, according to your too simplistic method of calculating the relative velocity between Alice and Bill, it would be 40 mph - 30 mph = 10 mph. That's not correct. You can't simply subtract two velocities to calculate the relative velocity between two objects when they are traveling in directions that are at right angles to each other.

 

And yet that is exactly what you did to find the relative velocity of the satellite clock to the ground clock: simple subtraction. And now you've even explicitly asserted that simple subtraction would work even when the two were traveling in paths that are perpendicular to each other.

[TeleMad]

quantum quack: I wonder how non-simultaneity can be proven as a physical pheno?

 

Is there any way that non-simultaneity can be proven apart from mathematical abstractions?

 

TeleMad quoting a college physics text: "Einstein devised the following thought experiment to illustrate this point. ...

 

Two events that are simultaneous in one reference frame are in general not simultaneous in a second frame moving with respect to the first. That is, simultaneity is not an absolute concept.

 

quantum quack: If it were just a matter of relative information delays due to the relative velocity of the moving observers it wouldn't be a problem for me.

 

However it seems that nonsimultaneity acquires a somewhat 'magical " quality to it once dilation and length contractions are accomodated.

 

 

Yes, taking length contraction, as used by Einstein in his special theory of relativity, into account when explaining the relativity of simultaneity can also be done easily. For details, you can do one of the following.

 

Buy the video lecture series Einstein's Relativity and the Quantum Revolution: Modern Physics for Non-Scientists: 2nd Edition, by Professor Richard Wolfson of Middlebury College, available at http://www.teach12.com, and watch lecture 10: Escaping Contradiction: Simultaneity is Relative.

 

Or, buy his book (Simply Einstein: Relativity Demystified, Richard Wolfson, W. W. Norton, 2003) that mirrors the relativity portion of his video lecture series and read pages 129 – 133. At just $13.95 it’s a great bargain, but if you like watching movies instead of reading books, the DVDs (from http://www.teach12.com) are better.

[quantum quack]

thanks for that info......Telemad

[paultrr]

As you shall see reciproicty is mandated by the "Relative Velocity" view. You are mixing some correct physics with SRT in a manner that is inconsistant with the theory.

 

Reciprocity applies only to comparisons between inertial frames. Once one frame is turned into a perfered frame(at some artifically constructed rest) then that frame is no longer considered an inertial frame because its actual motion has been canceled out. As such, Reciprocity is no longer valid. I think what you are messing is that its not the whole of relativity that GPS supports. Its aspects of it. For one, without the corrections the clocks in orbit have a different time than those on earth. The system was never designed to do anything but tract position on the earth with all the clocks appearing in sync via an artificial introduction of a perfered rest frame. I would grant that saying all of relativity is supported by such would be a stretch. But since GPS was not designed as an experiment to prove all of it to begin with and since the guidelines by which one can assume Reciprocity to hold do not apply because of the way GPS had to be set up its not logical to assume its lack of Reciprocity is evidence SRT is wrong. If anything it only proves that the statement that Reciprocity can only be applied in real inertia frames is true.

[quantum quack]

Reciprocity applies only to comparisons between inertial frames. Once one frame is turned into a perfered frame(at some artifically constructed rest) then that frame is no longer considered an inertial frame because its actual motion has been canceled out. As such, Reciprocity is no longer valid. I think what you are messing is that its not the whole of relativity that GPS supports. Its aspects of it. For one, without the corrections the clocks in orbit have a different time than those on earth. The system was never designed to do anything but tract position on the earth with all the clocks appearing in sync via an artificial introduction of a perfered rest frame. I would grant that saying all of relativity is supported by such would be a stretch. But since GPS was not designed as an experiment to prove all of it to begin with and since the guidelines by which one can assume Reciprocity to hold do not apply because of the way GPS had to be set up its not logical to assume its lack of Reciprocity is evidence SRT is wrong. If anything it only proves that the statement that Reciprocity can only be applied in real inertia frames is true.

so Paul you are saying that SRT can not be applied in this instance. Surely though does this not contradict the postulate that the laws of pphysics apply equally to all observers.

from what i understand SRT postulates certain things and those things must apply universally regardless of how something was set up.

 

Just becasue a preferred frame has been chosen doesn't allow SRT an ability to not apply I would think.

 

I can only ask my earlier question again and that being if the Earth clocks were seens as slow by the satelite clocks would the GPS system function at all.....?

 

Surely the Satelite clocks and Earth clocks must be synchronised and if this is so then the use of frames is not SRT as Mac is attempting to state. If SRT frame systems can't be applied then it leads to the question of just how selective SRT's application has to be.....

 

continuous synchronisation of clocks would be impossible if SRT was actually a physical pheno...yes?

 

if i remember MAc has made the allegation that not one instance of observable reciprication of dilation has been observed and recorded. If this is the case then how can the SRT equivilence of frames be proved as being valid?

 

to be proved the GPS must see the Earth clock running slow, there fore i fail to see how the GPS can function when it appears that synchronisation is designed into the satelite clock. If SRT was correct an impossible situation arrises where by both the satelite clocks and teh Earth clocks woudl have to be doctored and of course that would be counter productive. after all why set both clocks fast...hmmmm something fishy going on......

[paultrr]

so Paul you are saying that SRT can not be applied in this instance. Surely though does this not contradict the postulate that the laws of pphysics apply equally to all observers.

from what i understand SRT postulates certain things and those things must apply universally regardless of how something was set up.

 

Just becasue a preferred frame has been chosen doesn't allow SRT an ability to not apply I would think.

 

I can only ask my earlier question again and that being if the Earth clocks were seens as slow by the satelite clocks would the GPS system function at all.....?

 

Surely the Satelite clocks and Earth clocks must be synchronised and if this is so then the use of frames is not SRT as Mac is attempting to state. If SRT frame systems can't be applied then it leads to the question of just how selective SRT's application has to be.....

 

continuous synchronisation of clocks would be impossible if SRT was actually a physical pheno...yes?

 

if i remember MAc has made the allegation that not one instance of observable reciprication of dilation has been observed and recorded. If this is the case then how can the SRT equivilence of frames be proved as being valid?

 

to be proved the GPS must see the Earth clock running slow, there fore i fail to see how the GPS can function when it appears that synchronisation is designed into the satelite clock. If SRT was correct an impossible situation arrises where by both the satelite clocks and teh Earth clocks woudl have to be doctored and of course that would be counter productive. after all why set both clocks fast...hmmmm something fishy going on......

 

I've noticed you tend to take definitions of everything from math sources. Physics uses math. But physics unlike math requires more than the math as its proof. Basically, in physics a theory is designed around what nature shows us. At least that is the way things are supposed to work. SRT applies only to inertia frames period. It does not apply to every type of frame there is.

 

Usually, in what's considered non-inertia frames one uses Newton since in general there is little difference between Newton and a non-accelerated frame under SRT as far as results goes. More of the relativistic effects out there untill one gets up nearer to C(at least past say 1/4C) really do not amount to much of a difference to begin with. What the GPS system does via its programming is force the situation or condition to where when it comes to the presented values on the clocks its as if Newton fully applied. But the behind the public view via programming that's done translates between the two so that things like the requirement you mentioned no longer apply since one is no longer comparing two inertia frames anymore. What you are comparing is a non-inertia frame to an inertia one. In short, they invoke an engineered via programming version of Newton's absolute rest frame to get the job GPS was designed to do done. Anytime one has even an artifical version of an absolute rest frame the certain aspects of SRT do not apply anymore.

 

In short, don't always rely upon math sources to explain a physical theory. Even Einstein himself was not always clear on the entire SRT picture. With GR the model we use today is not exactly Einstein's original static model. SRT has been somewhat itself subject to a evolution of sorts when it comes to thought also. But, you might be interested in knowing that the subject of when certain aspects of SRT apply and do not apply is discussed from time to time on the math forums out there and the aspects I have mentioned are brought up there also.

 

In general, a lot of the crap one reads about SRT on the Internet is misleading to say the least. There are a lot of closet aether supporters out there on the net. I sometimes think Beardon's ideas have rather crept into the net in full force though the idea you raised is not his idea. Einstein's SRT does start with Lorentz. But it goes a bit beyond Lorentz. A lot of people never bother to notice that Einstein started out a believer in the aether and eventually gave the idea up since he could find no evidence for such. Yet, while one time saying the baby was dead, he later says long live the aether. I will not get into the debate about weither Newton's absolute spacetime is a correct way to look at Newton. But its also true that modern quantum theory rather filled up the empty spacetime Einstein first designed so perhaps those words of Einstein have some truth behind them. The difference is the aether of quantum theory has no absolute frame of reference. With the GPS system an artifical one is built into the system.

[TeleMad]

I've noticed you tend to take definitions of everything from math sources. Physics uses math. But physics unlike math requires more than the math as its proof.

 

Yes! Which is why it is not technically "correct" to call length contraction Lorentz contraction: it is relativistic lenght contraction.

 

The MATH of Lorentz (or Lortentz and Fitzgerald) works, but their PHYSICS does not. Lorentz argued that length contraction occurs because an object is moving through the luminiferous ether, which is an absolute reference frame; when something moves through the ether, it - and it alone - gets physically compressed in the direction of motion.

 

Einstein used their MATH but did away with their PHYSICS. In special relativity, the object is not physically compressed because it is trying to move through the ether, instead, there is no ether, and space (and time) itself - not just the object - is contracted.

 

So if one wants to be technical about it, when doing the pure mathematical calculations one can say they are basing their work on Lorentz - that is, on his equation - but when doing physics and trying to explain what is occurring in nature, it is not correct to attribute the basis of the work on Lorentz: then one has to give credit to Einstein.

[TeleMad]

quantum quack: I wonder how non-simultaneity can be proven as a physical pheno?

 

Is there any way that non-simultaneity can be proven apart from mathematical abstractions?

 

<other exchanges>

 

TeleMad: Yes, taking length contraction, as used by Einstein in his special theory of relativity, into account when explaining the relativity of simultaneity can also be done easily. For details, you can do one of the following.

 

Buy the video lecture series Einstein's Relativity and the Quantum Revolution: Modern Physics for Non-Scientists: 2nd Edition, by Professor Richard Wolfson of Middlebury College, available at http://www.teach12.com, and watch lecture 10: Escaping Contradiction: Simultaneity is Relative.

 

Or, buy his book (Simply Einstein: Relativity Demystified, Richard Wolfson, W. W. Norton, 2003) that mirrors the relativity portion of his video lecture series and read pages 129 – 133. At just $13.95 it’s a great bargain, but if you like watching movies instead of reading books, the DVDs (from http://www.teach12.com) are better.

 

 

Okay, had some time to work this up. The following explanation is directly based on (but is not as detailed as, nor is it a quote from) professor Richard Wolfson’s explanation of the relativity of simultaneity in his video lecture series and his book.

 

PS: This is all correctly laid out when viewed in the original document, and I've used [ code ] tags to try to retain that formatting, but I don't know if everything will line up properly. If not, it shouldn't be difficult to figure out what is going on.

 

Consider two airplanes, A and B, in uniform motion, moving in exactly 
opposite directions, that pass each other.  There are two events of interest: 

(1) the event of the nose of plane A coinciding with the tail of plane B.  

and 

(2) the event of the tail of plane A coinciding with the nose of plane B.  

Three different diagrams are presented, each from a different frame of 
reference.  Event (1) will be indicated using an asterisk (*) whereas 
event (2) will be indicated using a plus sign (+). 





First, from an inertial frame of reference in which both planes A and B 
are moving at the same velocity.  Since the planes are traveling with 
the same rate in this frame of reference they are both length contracted 
to the same degree.  Here we see the two events occur simultaneously.


A          <----------|
                

          *           +

B          |---------->
                /





Second, from an inertial frame at rest with respect to plane A.  B is now 
more length contracted, but A is not length contracted at all.

A          <--------------|
                  

          *          

B          |-------->
               /



A          <--------------|
                  

                          +          

B                |-------->
                     /

As we can see, although event (2) was simultaneous in the first frame 
of reference, it is not simultaneous in this one.  

Thus, the relativity of simultaneity: two events that are simultaneous in 
one inertial frame of reference are (generally) not simultaneous in another 
inertial frame in motion relative to the first.

And although this can be demonstrated without relying on relativity, here 
the explanation goes that extra step to include – indeed, to be based on – 
a relativistic property. 





Third, from an inertial frame at rest with respect to plane B.  A is now 
greatly length contracted and B is not length contracted at all.

A                <--------|
                      

                          +          

B          |-------------->
                  /



A          <--------|
                

          *

B          |-------------->
                  /

As we can see, although event (1) was simultaneous in the first frame 
of reference, it is not simultaneous in this one.  By now that shouldn’t 
surprise since we already saw the relativity of simultaneity.

What then is the point of this third diagram?  To show this.  Even more 
spectacular than the fact that the events weren’t simultaneous in this 
reference frame is the fact that event (2) occurred before event (1)!  
Yes, although event (1) occurred first in the second frame of reference, 
event (2) occurs first in the third frame of reference!

So not only is simultaneity relative, it is also possible for the time order of 
two certain types of events to be reversed!

[Damo2600]

Hi guys,

 

I'm sorry to butt in. You all obviously know more about this than I do. But the problem that Mac is having is the same as I am. This Reciprocation combined with time dilation does seem to be a thorn in ones side when trying to understand Special Relativity. These two pricinples logically contradict one another.

 

I've addressed this issue on more than one forum and noone has offered a specific answer. How can this SPECIFIC aspect of Special Relativity really work ?

 

The problem with the GPS clocks, to state it more specifically, you can doctor the clocks on the satelite to run at the same clock speed, i.e. as the clocks on earth's surface, using SR.

 

Sounds simple enough.

 

Information relayed should be correct for our time. However, as Mac and Quantum Quack are pointing out, the satelite should see everthing on Earth to be going twice as slow than using the unaltered clocks. If it were that easy then it is not special relativity we are dealing with because SR goes beyond clockspeeds. Just by speeding up the clocks does not make everyones observations the same. The longer the satelite travels the slower time on earth should appear. Speeding up the clocks serves to only make the problem worse logically.

 

So we have a problem because GPS obviously works does it not? I don't own a car so I wouldn't have a clue.

 

Spacetime and velocity alters the clocks, and if SR were to be true, then there is nothing a scientist/physicist/GPS operator could possibly do to alter this fact. Clocks themselves do nothing but count. Clocks and scientists are not in control of spacetime. That WOULD be a feat.

 

So this example really shows the difficulty I am having as a totally confused beginer (Part two).

 

Do you guys understand the problem?

 

Supposing that because the distance is not growing between earth's centre of gravity and the satelite perhaps time is not effected. This would not make sense. That means relativity has more to do with altering distances and than it has to do with motion alone. This isn't what we are taught though.

 

I hate this. Relativity is like a model that always falls apart when I try to put the last peice place.

 

Thanks

Josephine

[TeleMad]

But the problem that Mac is having is the same as I am. This Reciprocation combined with time dilation does seem to be a thorn in ones side when trying to understand Special Relativity. These two pricinples logically contradict one another.

 

That is a key issue and I believe it deserves its own thread, because it is likely to be an extensive discussion.

 

However, in examining possible problems of reciprocity in SPECIAL relativity, we should really STOP discussing GPS and orbits and instead switch to talking about standard uniform motion: where we perceive objects as moving in a straight line at constant speed.

[Damo2600]

Hi,

 

The funny thing is that if we think in terms of Euclidean geometry time still does appear to slow down. If I travel away from you the light is taking longer to get to me so I see your time as slower. What light as a constant brings to the table is that time doesn't slow down as much as in Euclidean geometry due to length contraction and time dilation. This is a limiting factor. Yet it also becomes apparent that the effects on time are permanent i.e. any relative movement brings about time changes that cannot be reversed in our current understanding. Now I was first struck with the in comprehensibility of Special Relativity when I was 16 yet had only recieved half the story. I had learnt that a ray of light bouncing perpendicular on a train is the same for all observers. I pondered this for years. Now I realise that this is the same for the light bouncing next to all observers as well. Suddenly it made even less sense.

 

So the SOL is a limit with regards to time. The limit being zero (or frozen) time. All other times can be gained through understanding this as a fact. The speed of light could be stated therefore as an absolute constant timespeed.

 

So we can say that you cannot observe light (in vacuo) to be travelling slower than this constant. Therefore time and distance is relative proprtionately to the SOL (this is a clue to explanation). So as I am travelling away from you (stationary) time slows and distance shortens for both of us proportionately to the speed of light. If I am orbiting the earth at 99.99% the speed of light I should see the light bouncing next to you as the same speed you see the light bouncing next to me. Everything happening in your reference frame appears so slow to me and the same for your observations of me.

 

At this point we fail in our understanding because my time is a fraction of your time yet I still see your time going slowly. So according to me travelling almost the speed of light time on the ship appears perfectly normal. According to me it is you who is traveling at 99.99% x c and therefore your time appears slower.

 

Logically we consider, like on the movie 'the time machine', that everything stationary should appear to be going in fast forward. So when we slow down to a crawl we have just watched the future hurry along and now we can meet our great great..great grand children at a respectable age.

 

Is it that everything appears to slow down yet when we start decelerating time speeds up in an awful hurry? Well this couldn't make sense either.

 

This is where we have a problem and the GPS thing is part of the explanation we are seeking. On one hand we have time slowing down and for observerA time does appear to slow down. We can handle that easily. The situation in reverse is that time speeds up yet for observerB it appears to slow down.

 

There is no way Mac or I can understand this without finding fault. No matter how much I try to understand the math it remains incomprehensible to me.

 

Reciprocation, the speed of light as a constant and 'actual' time dilation don't all fit together simultaneously.

 

Thanks

Josephine

[TeleMad]

Damo2600: This is where we have a problem and the GPS thing is part of the explanation we are seeking.

 

Stop looking at GPS for SPECIAL relativity.

 

Special relativity pertains only to reference frames in uniform motion. And when comparing two different frames in relative motion to one another, they must both be in uniform motion from both points of view. THIS DOES NOT HOLD FOR GPS.

 

Consider a clock on the Earth's surface at the equator. In its reference frame it is in uniform motion. But when it looks up at the satellite, that satellite's motion relative to the ground clock is constantly changing velocity: the ground observer sees the satellite's speed and/or direction of motion changing all the time. For example, as the satellite dips down over the horizon in its curved trajectory, both its direction and speed relative to the ground clock changes.

 

The same things happens from the perspective of the satellite clock. In it's frame of reference it is at rest, moving uniformly (free fall). But when it looks to the ground clock, the satellite sees the other clock accelerating ... NOT in uniform motion.

 

If you are having problems understanding special relativity then you need to change what you are looking at. Try using the simplest example.

 

 

Damo2600: On one hand we have time slowing down and for observerA time does appear to slow down. We can handle that easily. The situation in reverse is that time speeds up yet for observerB it appears to slow down.

 

There is no way Mac or I can understand this without finding fault. No matter how much I try to understand the math it remains incomprehensible to me.

 

I've said this before and I'll say it again. THERE IS NO CONTRADICTION.

 

Simply stated, observer A can say "I'm at rest and observer B is in motion, so his clock runs slower than mine", and observer B can say "I'm at rest and observer A is in motion, so her clock runs slower than mine", WITHOUT THERE BEING ANY CONTRADICTION. There only APPEARS to be a contradction.

 

The way out is how I've been saying all along: it relies upon understanding the relativity of simultaneity: two events that are simultaneous in one inertial frame of reference are (generally) not simultaneous in a second inertial frame of reference in relative motion to the first. There's the key.

 

To explain in detail why that solves the apparent contradiction would require a lot of typing and a lot of explaining on my part: and since I'm banging my head against the wall to get people to see simple things, I'd also be encoutering a lot of resistance, making it all the harder on me.

 

So, as I have alluded to before, if anyone really wants to see how the relativity of simultaneity destroys the APPARENT contradiction, they can find this clearly explained; they just have to fork over the mere $13.95 to buy Richard Wolfson's book "Simply Einstein: Relativity Demystified" and read chapter 10, "The Same Time?".

[GAHD]

It remains incomprehensible because noone can provide raw data from multiple frames of refrence for study. Thus theory and not fact.

[TeleMad]

It remains incomprehensible because noone can provide raw data from multiple frames of refrence for study. Thus theory and not fact.

 

Einstein's special relativity is a theory, but it's also a scientific fact.

 

Again, there is no contradiction: simply put, both observers can see the other's clock running slow.

 

I've pointed out several times now where anyone can obtain the information needed to see this. Anyone who continues to claim there is an actual contradiction is just too lazy (or whatever) to bother doing the work needed to find this out.

[Damo2600]

Thank you for taking your time out to try to explain this to me Telemad.

 

So let's suggest that the speed of light is not always constant. I have read, in the last couple of days, that this is true in some forms of movement. So the satelite does see the earth's clock going fast at a velocity greater than 10% x c. There is an apparent time slowing and speeding as explained by euclidean geometry. But over all time does speed up. The effects are minimalised due to the close proximity of the satelite with regards to earth's surface. With a maximum discrepancy of 1 or 2 seconds when the satelite is at the horizon.

 

What do you think Mac and Quantum Quack? According to what I've just said reciprocation is not perfectly symetrical in this instance (of the satelite) and the speed of light is not always constant. This is what we had thought. It may not be the answer we were expecting but I suppose it is an answer. Does this contradict SR?

 

I have to consider how this effects bodies in uniform motion i.e. traveling in a straight line between two points.

 

Thanks again

Josie

[Damo2600]

O.k. I've considered it but I have to go out so I'll explain later.

 

Thanks, Josie

[GAHD]

Einstein's special relativity is a theory, but it's also a scientific fact.

 

Again, there is no contradiction: simply put, both observers can see the other's clock running slow.

 

I've pointed out several times now where anyone can obtain the information needed to see this. Anyone who continues to claim there is an actual contradiction is just too lazy (or whatever) to bother doing the work needed to find this out.

on SR: If it was end all fact Einstein wouldn't have released the revisions (GR) later, and we wouldn't be searching for a unified feild theory.

 

I have repeatedly searched for the data from the (edit: Haefel - Keating) experiment (the end al proof everyone is always toting), no one has yet been able to provide it.

 

Please proove me wrong and actually post data; better yet, show me two videos of objects focused on each other from two seperate refrence frames actually showing length contraction and time dilation. No such video exists. Untill one does it's all just claims.