Nature of Time Dilation and Length Contraction

[Pete]

Hi Cangas,
Thankyou for pointing out that my record speaks for itself. I'm sorry that about your apparent inability to understand my substanstive statements; I do hope that you get that problem resolved.

Before I do an analysis, I really need to know what level of analysis you're thinking of; whether you're doing the simple analysis that all relativity students do, or if you're going back to the raw data of MIchelson and Morley, or something in between.

If the first, then I've already done it. So have thousands of others, and a simple web search will find it for you.

If the second, then I'll need your help, since I don't have access to Michelson and Morley's data.

If it's something in between, then please explain.

 

[CANGAS]

Hi Pete:

My explanation to you;

You do the best you can, to prove or disprove the concept of the Michelson interferometer, and to prove or disprove the legitimacy of the Einstein invention and derivation of gamma, and then you look at your own results and decide if you have done anything significant to prove or disprove these things. Then you decide what you want to present to us for our study.

I have begun my serious study, belatedly, without any help from you or any other member of these forums. And, when my work is satisfactory to my own opinion of its completeness, I will present it.

Why do you plead to me for help before you can begin your own study?

As I have already stated, a serious study of these matters will immediately disclose serious problems. If you are not aware of the problems or their alledged solutions, then you simply have not already executed an adequate study.

If you have me confused with your drill instructor, you are just not focused.

 

[Pete]

Thanks CANGAS.
Yes, I've studied the concept of the Michelson interferometer.
Yes, there are a number of issues involved.
Yes, I think that special relativity is the most satisfactory explanation for the results of the experiment, when other observations are considered*.

I commend you for studying the matter on your own from first principles, and I look forward to hearing your results.


*I don't think that the Michelson Morley experiment alone is enough to justify Special Relativity, but considering it with other results such as the abberation of starlight and extended half-lives of high-speed particles is enough to convince me.

 

[2inquisitive]

Relativity is not necessary to explain the aberration of starlight. Here is a link from a NASA site that uses Bradley's observations and basic math to obtain the correct answer.

However, it turns out that the displacement of the direction calculated by Bradley was the same as what relativity would give. Let us calculate it here the way Bradley might have done, ignoring relativity and using the same "pre trigonometry" introduced in the section on parallax.
In the drawing shown here, let A be the Earth and AP the direction towards Polaris (the star itself is much more distant). The vector PA represents the velocity of light coming from Polaris at c=300,000 km/s. The vector AB represents the velocity –u of Polaris relative to Earth, equal in size to the Earth's velocity u=30 km/s in its orbit, but in opposite direction. (To simplify the calculation we assume AP is perpendicular to AB, in which case the apparent motion of the star is a circle; actually the angle is usually less than 90° making the apparent motion not a circle but an ellipse.) The point P ' indicates the apparent direction of Polaris as viewed from Earth, offset by an angle a=40" from its actual direction.



The length of each side in the triangle ABP is proportional to the velocity it represents; obviously its dimensions are not drawn to scale (it would be hard to draw a triangle with one side 10000 times longer than the other!). If the triangle is viewed as a pie-slice from a circle and the angle at P is denoted by a, we get

30/(2p 30,000) = 30 / 60,000p = a/360°
a= 10800 / 60000p = 5.7296 / 1000 degrees.

Each degree contains 60 minutes of arc (60') and each minute has 60 seconds of arc (60"), units unrelated to the minutes and seconds of time. Each degree thus equals 3600", giving


a = 3600" (5.7296 / 1000) = 20.6"
Half a year later the direction of u is reversed and the displacement is in the opposite direction, giving an annual range of about 40", as observed.

http://www-spof.gsfc.nasa.gov/stargaze/Saberr.htm

 

[James R]

CANGAS:

Your investigations were apparently more frivolous than painstaking. The problems I have uncovered would be immediately obvious to any serious study. Since you have not mentioned and refuted them, it is obvious that you have never discovered them, which means that you have never studied the matter in depth.

Or, it could simply mean that what you regard as "problems" are in fact not problems at all, and you're deluding yourself.

Since you haven't specified what these supposed "problems" are, there's no way to tell.

My results, whether in favor or against the legitimacy of Special Relativity, will be made available when I have satisfied myself that I have done the most thorough work I can do. This will happen on my schedule. Not yours.

That's fine. I'm willing to wait. My guess is you'll never publish anthing, but will instead go on making unsupported claims about imaginary "problems". But I could be wrong.

 

[Pete]

Relativity is not necessary to explain the aberration of starlight. Here is a link from a NASA site that uses Bradley's observations and basic math to obtain the correct answer.
http://www-spof.gsfc.nasa.gov/stargaze/Saberr.htm

Correct. Aberration of starlight on its own is insufficient to justify special relativity.

But it is sufficient when taken together with the null result of the Michelson Morley experiment, and with later tests.

 

[2inquisitive]

Correct. Aberration of starlight on its own is insufficient to justify special relativity.

But it is sufficient when taken together with the null result of the Michelson Morley experiment, and with later tests.

I thought light propagated through the atmosphere on Earth's surface, a medium. I thought the atmosphere rotated with the Earth. Why should a interferometer located on Earth's surface, with the light source fixed to the interferometer, show a fringe pattern? Do you think a fringe pattern would show if the interferometer were moving through the atmosphere, unshielded from the wind? This is an important question, as it relates to my hypothesis.

Edit to add: Some physicists claim the speed of light is reduced as it falls through the Earth's atmosphere because it is 'absorbed and re-emitted' by atoms in the atmosphere. I don't think this is the main reason the speed of light is slower near Earth's surface. I believe the speed of light would also be slower near Earth's surface even if the Earth had no atmosphere, just as an atomic clock's tick rate decreases as it moves lower in the gravity well. If the slower speed of light were due to 'absorption and re-emission' of photons, the speed would be virtually unaffected at short distances when both the emitter and receiver were located on Earth's surface. Also, wind speed in Earth's upper atmosphere has no observable effect on the direction of propagation through the atmosphere. Ionization in the upper atmosphere does have effects, as measured by GPS signals, but that is a separate effect.

 

[Pete]

Now you're only thinking about Michelson-Morley, without considering the aberration of starlight. Don't do that. The two must be considered together. Your question has been considered and addressed in the literature, chiefly by Lorentz, I think - have a look. A web search might not be sufficient. Briefly (with much discussion and details omitted):

If the stuff that light propogates through at c (whatever it is) is moving with the Earth's surface, then the Michelson interferometer null result is explained, but the aberration of starlight is not, unless the stuff has very peculiar properties.

On the other hand, if the stuff that light propogates through at c is stationary with Earth moving through it, then the aberration of starlight is explained but the Michelson interferometer null result is not, unless the stuff has very peculiar properties.

 

[2inquisitive]

Pete, the starlight is comming from a distant star, the Earth is moving in its orbit while the starlight is propagated in a straight line, hence the aberration. The Mickelson interferometer used a stationary light source mounted on the interferometer itself. There was no motion relative to the light source to display a fringe pattern.

Edit: By the way, the Gravity Probe B experiment did have to account for the aberration present in the light from the guide star, even though there was no atmosphere in the vacuum where the experiment took place.

 

[Pete]

Edit: By the way, the Gravity Probe B experiment did have to account for the aberration present in the light from the guide star, even though there was no atmosphere in the vacuum where the experiment took place.

Yes, that's what relatvity predicts. The trick is to explain both aberration of starlight and the null result of Michelson Morley with a single theory.

This is not a simple issue, 2inq. Before continuing, I highly recommend that you read up on:
1) Fresnel's partially dragged ether theory (the experiments of Arago, Airy, and Fizeau are relevant), and why it is not generally accepted (it predicts a non-null result for Michelson-Morley experiment).
2) Stokes' dragged ether theory and why it is not generally accepted (mainly because the ether must be compressible, but the speed of light through the ether must not be affected by the density of the ether).
3) How Lorentz addressed the issue

Here are some sources for you:
19th Century Ether Theory (PDF)
Stellar Aberration

 

[2inquisitive]

Pete,

Yes, that's what relatvity predicts. The trick is to explain both aberration of starlight and the null result of Michelson Morley with a single theory.

I already have, Pete. Read again. There is nothing about either that is not compatible with my hypothesis, plus I can explain the blue shift in the radio waves from the Pioneer/Voyager spacecraft naturally. My hypothesis was based upon experimental evidence. That is what led me to my conclusion and hypothesis.

Stokes' dragged ether theory and why it is not generally accepted (mainly because the ether must be compressible, but the speed of light through the ether must not be affected by the density of the ether).

In my hypothesis, I proposed the 'ether' is compressible by gravity. The ether is more dense near gravitating bodies, attracted by gravity or a property of a gravitational field itself, rotates with the planet (the Lense-Thirring effect) and the speed of light is affected by the density of the ether. A simple thought experiment will confirm the speed of light is dependent upon the density of the ether. I will give this below.

I assume you do not disagree that atomic clocks beat at different rates according to their location in the gravity well, faster as they move away from the gravitational source. Use the atomic clock to measure the speed of light 'in a vacuum'. You are familiar with the SI definition of 'c', right? It is based on a cesium clock. When you measure the speed of light from a satellite in mid-heigth orbit, such as a GPS satellite, that value is in a vacuum far above Earth's atmosphere (not a low orbit satellite). Move the cesium clock higher into geostationary orbit. The cesium clock will tick relatively faster in this location. I have looked up the values before, but I don't remember them offhand. The cesium clock was in a vacuum in BOTH locations, but it increased tick rate as it was moved higher in the gravity well. The speed of light must increase at the higher position as well, because it is defined by the cesium clock and the meter. Think the meter is longer in the higher location? Think again what effect that would have on the speed of light. It would require a shorter meter higher in the gravity well if the speed of light stayed the same, but the clock had a shorter interval between ticks. No, 'c' varies by location in the gravity well. Light slows as it encounters ever increasing density in the either. When I say ether, it is like a gravity field composed of particles which move within the field very little. A gravitational wave is a disturbance that travels through the field like a sound wave through the atmosphere. The entire solar system is enclosed in a 'bubble' of ether, the density of which falls off at the termination shock boundry. That is the location when the anomolous blue shift in the radio waves was seen. The speed of light increased measurably when this location far outside planetary orbits was breached, registering as a blue shift here on Earth. Please check out the illustration on this NASA site to understand what I am describing.
http://www.nasa.gov/vision/universe/solarsystem/voyager-interstellar-terms.html

 

[CANGAS]

James R :

It is most delightful that you are willing to wait, since my disclosures will be done ON MY SCHEDULE, not on the schedule of someone like yourself.

To redundantly be repetetive, for the second time, the problems of the Michelson interferometer and the thinly disguised Einstein conception and derivation of gamma are immediately apparent to a serious mathematical study, so your failure to state them and rebut them are a failure of your own diligence in a matter which you self proclaim to be important to you.

Whether or not the disclosure of my continued work throws gloom upon Relativity or illuminates it, your inability to to anticipate my discovery of problems, and their possible solutions, or lack, casts grave doubt upon your credibility.

My work is so far preliminary and will certainly be modified, pro or con, by further work. At this point, if Relativity were a horse race, I would not advise buying a $2 ticket, unless you have found a race track that sells bets on dead last.

 

[Pete]

Pete,

I already have, Pete. Read again. There is nothing about either that is not compatible with my hypothesis, plus I can explain the blue shift in the radio waves from the Pioneer/Voyager spacecraft naturally. My hypothesis was based upon experimental evidence. That is what led me to my conclusion and hypothesis.

In my hypothesis, I proposed the 'ether' is compressible by gravity. The ether is more dense near gravitating bodies, attracted by gravity or a property of a gravitational field itself, rotates with the planet (the Lense-Thirring effect) and the speed of light is affected by the density of the ether.

This is very interesting, and I would like to hear more.
Can you give quantitative details for your hypothesis? For example, can you describe how I would calculate the expected angle of starlight received from a particular star when Earth has a particular motion relative to the ether?

 

[Pete]

To redundantly be repetetive, for the second time, the problems of the Michelson interferometer and the thinly disguised Einstein conception and derivation of gamma are immediately apparent to a serious mathematical study, so your failure to state them and rebut them are a failure of your own diligence in a matter which you self proclaim to be important to you.

Make it worth our while, CANGAS. When you show us that the problems are with the experiment and/or theory, and not with your own understanding or application, then we'll take you seriously.

TAKE YOUR TIME. I wouldn't want to try to set your schedule for you.

 

[2inquisitive]

Pete,

Can you give quantitative details for your hypothesis? For example, can you describe how I would calculate the expected angle of starlight received from a particular star when Earth has a particular motion relative to the ether?

No, I'm not really interested in the math, nor do I have the necessary knowledge of math. That Is the reason I called this my 'thought experiment' at times, or my little hypothesis. That is referring to 'quantitative details'. As to how I would describe how to do the calculation, I already have in my link to the NASA site earlier. The starlight generally follows a straight line in interstellar space, the Earth moves through this space. If you are referring to effects caused by an ether that 'moves with the Earth', it moves relative to the starlight at the same velocity the Earth does, correct? That is what causes the aberration of starlight.

Now, can you explain the Shapiro delay using a constant 'c'? That is when light takes longer 'than expected' to pass through a gravitational region. This has been measured by modern astronomers. The Shapiro delay is not gravitational lensing per se, the location of the distant object is not skewed, nor are there any multiple images of the object.

Edit: Pete, I don't know if you read my earlier post in another thread outlining my hypothesis. It got lost in the discussion, different posters discussing different things. In general, I hypothesized that the permittivity and permeability was directly connected to the properties of the vacuum. Yes, I know that is the standard description, but I believe those properties vary with vacuum density. The density of the vacuum has also decreased over time since the big bang with the expansion of the universe, leading to relatively different speeds of light over time. Electromagnetic processes speed up with lower density, slow with increased density, including atomic clocks (but not mechanical pulsar clocks) and the speed of light. Here is a link:
http://sciforums.com/showthread.php?t=53590&page=32&pp=20

 

[Pete]

Pete,

No, I'm not really interested in the math, nor do I have the necessary knowledge of math.

Then it's not a testable hypothesis, and it's not interesting to me after all. I suspect that if you did work it through, you'd find that it would not predict the observed aberration of starlight.

Sorry, I don't know anything about the Shapiro delay. Wikipedia says that it was predicted by General Relativity theory and then confirmed by observation, but I don't have a great understanding of GR.

 

[2inquisitive]

Pete,

Then it's not a testable hypothesis, and it's not interesting to me after all. I suspect that if you did work it through, you'd find that it would not predict the observed aberration of starlight.

How do you equate my not being able to model the hypothesis mathematically with 'its not a testable hypothesis'? I suspect if you knew how to model the aberration of starlight correctly, you wouldn't make such an ignorant statement. It has nothing to do with a hypotenuse of a right triangle 'being too long'. The photons that reach the Earth after the Earth has moved to the new location are not the same photons that were emitted when the Earth was at the first location.

 

[James R]

CANGAS:

It is most delightful that you are willing to wait, since my disclosures will be done ON MY SCHEDULE, not on the schedule of someone like yourself.

You already said that.

To redundantly be repetetive, for the second time, the problems of the Michelson interferometer and the thinly disguised Einstein conception and derivation of gamma are immediately apparent to a serious mathematical study, so your failure to state them and rebut them are a failure of your own diligence in a matter which you self proclaim to be important to you.

If what you say is true, it is surprising to me that these problems of yours weren't pointed out immediately Einstein first published his theory, in 1905.

Perhaps it was the Grand Scientific Conspiracy covering things up, as usual.

Whether or not the disclosure of my continued work throws gloom upon Relativity or illuminates it, your inability to to anticipate my discovery of problems, and their possible solutions, or lack, casts grave doubt upon your credibility.

No. The fact that you make outrageous claims backed by nothing casts grave doubt upon YOUR credibility.

If you had any credibility, you would have said nothing until you were ready to publish your revolutionary findings "on schedule".

 

[Pete]

How do you equate my not being able to model the hypothesis mathematically with 'its not a testable hypothesis'?

Testable means making a numeric prediction, and seeing if that predication matches observation. Making a numeric prediction means mathematical modeling.

 

[2inquisitive]

Testable means making a numeric prediction, and seeing if that predication matches observation. Making a numeric prediction means mathematical modeling.

Fair enough. Now tell me what Special Theory predicts predicts when an atomic clock moves from mid-Earth orbit to geostationary orbit. Does ST predict the clock will beat faster or remain unchanged?