Mac's Final Relativity Thread

Just something everyone here should remember and take to heart.




There is not a single concept of which I am convinced that will survive and I am unsure whether I am on the right way at all.

Albert Einstein (1949)

 

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Your right about this. I noticed the error as going to bed and did not correct it. The end of the rope would move away from me even if he did not. (I.e. he accelerated “just right” for him to remain stationary for me by my measures as you suggest in this post.) And if he is coming closer by my meter sticks, as you suggested in earlier post, then the end of the rope can remain at my side.

Your words are too ambiguous to be clear: If the two blue "you"s refer to the one who accelerates then this is false as he does move wrt to me as he measures it. Again the red words "never move" are only true wrt me in my frame measured by my meter sticks. I.e. the distance to the rocket from me is remaining constant as I measusre it But NOT as he measures it. You need to tell more clearly what you mean. (But for both of us, the end of the trailing rope is moving away from me. For me true as the space between each of the 400 knots is growing shorter. For him true as he is moving away from me.)

On can consider that the rocket is constantly joining a new inertial frames for zero time. In each of these new frames his higher velocity contracts the growing separation distance, measured in his frame, more for me to make his separation from me by my measure constant,while by his meter sticks he is leaving me far behind.* Since he is stationary in terms of my meter sticks, Newton's third law applies. It states that a stationary object has zero net force on it. (Both F & d in the work equation, are constants for me.) So he is not doing any work in my frame. Yes, I see his rocket burning fuel but it is not doing any more work than is being done on the stationary logs in a bonfire as they oxidize.
Energy is conserved in my frame by chemical energy becoming heat - just like a bonfire.

Likewise if I consider the KE in a set of other frames, each of which is moving faster wrt my bon fire then that bon fire is gaining KE in those frames. KE is relative to the frame. There is always some frame in which the KE of the bullet I just fired is zero - that does not mean that energy is not conserved.

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*Again your lack of understand is due to your lack of precision with a words only description.

If, I were as ambiguous / vague as you are, I can say both:
(1) He does not move. (As you did.)
(2) He is moving very rapidly.

(1) is true if I measure with my meter sticks the distance to him. (Assuming with you he is accelerating ”just right.”)
(2) is true if he measures with his meter sticks the distance to me.

For example, from his POV, the 400 knots in the rope he is trailing are neither changing their separations nor is the end staying over my head as it was when he first let lose his rocket blast. The distance back to me, measured by his meter sticks is increasing. I.e. that distance is more than the CONSTANT TO HIM length of the trailing rope. The gap between me and the end of the trailing rope is increasing. – End of rope is moving away from me for both of us.

There are no mysteries here - only ambiguous use of words in your post make it seem so.

 

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Ever hear of a "Heat Balance"? I've done those in the power plant many time. The rocket producing heat does not change in different frames. What changes in the work produced.

The fact is from earth you are still accelerating away and from your frame as pilot the universe in front of you is closing in but that rear view mirror says you as spinning your wheels.

You miss the point as I stated above.

Your text seems all mixed up. Who is "my", "me" "Him", "his", "he", "us" ?

Impossible to reply to this without clarification.

Never said it was a mystery or paradox, I said it is BullS___T.

 

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MacM's (and QQ's) basic tactic seems to be to put up some (usually non-sensical, but defaulting to false in the rare case of the blind chicken) fabricated distortion of what fundamental relativity theory is or implies. Then - with the usual crackpot hubris and almost complete ignorance of (or worse, indifference to) the supreme arrogance they demonstrate by their implying idiocy on the part of thousands of very, very, very smart people who've studied these theories in depth for a century - when nobody rushes to defend their obvious strawmen, to claim that failure to do so demonstrates the failure of the theory.

Such threads do not belong here. The time for rational response is long past, and only ridicule is left - even the temperate BillyT and CptBork have exhausted their otherwise seemingly limitless patience.

So I say: Begone! Away to the Cesspool with you, foul thread, to corrupt this forum nomore!

 

funkstar,

The idea that an observer, by simply moving, can contract space-time in the entire universe, and do it in such a way that other observers can't witness the contraction is something that definitely belongs in the Cesspool.

If I was to say that by wiggling by finger, I can cause a star on the other of the galaxy blow up, and in such a way, no one else would see it, I would be called crazy. If Einstein says it, then it's genius.

 

SRT does not state that. He only dilates time and contracts space AS HE MEASURES IT. For all others the distance to Alpha Centaurs remains unchanged etc.

At least learn what SR states before attacking it.* Even MacM does that, but I have my doubts about QQ doing the same.
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*If that is your intent - I am not sure of your point. (The "If Einstein says it, then it's genius." made me think that is your point.)

 

Billy T,

Are you saying that actual space-time does not physically change, only the moving observer's perception of it does?

 

I don't use the words "perception" "sees" "observes" etc. if I can avoid doing so as that gets confused with simultaneity and delay of light questions, but basically yes, if correctly measured (and that is not easy) the rest of the universe contracts and time dilates only for him.

I do not understand how one could possibly think as QQ does that an acceleration, which was over 150 years ago, can leave a permanent change in the energy levels of a cesium atom so that the frequency used in a cesium atomic clock, moving wrt me is different than my cesium based clock. That even violates the idea that physic is the same in all inertial frames! If holing QQ's POV you also must believe that there is a preferred frame. I.e. it is the one for which all other frames in inertial motion wrt to it have time dialtion. I.e it is the frame with the shortes second - clock ticking faster than any clock in any other frame!

From QQ's position, a great deal of nonsense follows. IMHO, same is true of MacM's POV, but he does not think there is only one preferred frame - there are many called the last "common rest frames" and time dilation is correctly calculated for a moving clock ONLY by inserting its speed wrt that "common rest frames" into the standard SR formulae. This is less silly, or at least harder to show the sillness, than QQ's "acceleration made a permanent change" POV.

 

I think now I understand what this thread's really all about, it sounds like what I used to say about relativity when my parents explained it to me as a kid, so I'll summarize it:

"Mommy, nooooooooooo!!! Say it ain't so! Tell me space and time are absolute!!! Waaaaaaaaaaaaaaaaahhhhhhh!!!!"

Space and time work in strange ways, they manifest themselves differently in different reference frames. That's a simple fact which agrees with all the evidence to date, and it's the only basis on which we've been able to move forward and explain and predict how things work in the real world. Maybe you think the predictions of particle spins, charges and masses, like in the case of the W boson or the pion, are complete flukes, and quantum field theory got all these predictions bang on by sheer luck. Luck on that magnitude would be more absurd than anything we physicists have ever said here to date.

No mechanism need be cited in relativity for why spacetime behaves the way it does. Physics answers the how, not the why- Einstein gave equations describing how spacetime behaves, he didn't say anything about why it does so, just like Newton gave equations for gravity without explaining why nature chose them. What's really absurd is that MacM and Quantum Quack demand that we conform to their sense of intuition and "common sense". That's the grounds they cite for why we're supposed to collectively just give up and start over again from 1900, because it doesn't fit with their "common" sense", not because there's some series of experiments proving Special Relativity doesn't work in the domain in which it's meant to be applied. Apparently, our day-to-day intuition is as good at relativistic velocities as it is in everyday life, even if noone's found a way to make this day-to-day intuition work to explain what we see in the labs.

In the case of MacM, at least the guy has indicated a fairly impressive technical background in his respective fields. From all indications it seems he has a good background in applied mathematics including calculus, and I can tell that he's at least worked with the Lorentz transformations, even if he also seems (from my POV) to have had some trouble understanding the full consequences.

As for you, Quantum Quack, I don't have too much to say. You come out and talk about Einstein and his followers like we're a group of complete numbskulls out to lunch, yet you candidly admit you have neither the "time" nor "resources" to do any serious study of the things you mock. Apparently, since your "common sense" prophetically dictates reality, you have no need to study the things you attempt to discredit, so you must understand that likewise, on the same grounds, physicists feel no need to take you seriously either. If you want to show us you're serious, start by studying some quantum mechanics and then explain to us why quantum mechanics doesn't allow potentially past-altering communications to travel faster than c, even if quantum signals themselves can be shown to do so. That seems to be a major fallacy in your understanding and you keep repeating it to us, so let's see your commitment, go look up why your argument is wrong and explain it to us.

 

Billy T,

I know that James would object with your statement. I had a discussion on Sciforums a while ago with James, and he clearly indicated that he believed that space-time actually physically changed, but only for the moving observer

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confused

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. But if space-time doesn't physically change, why modify all the physics equations to adjust for that change, instead of just disregarding what the observer sees as an illusion?

I simply believe that for a clock that is moving through a gravitational field, light slows down. Therefore, the reactions in the clock slow down, causing the clock to tick slower. No need for time dilation or length contraction.

 

Because it is not an ilusion. It is a real effect on him.
For example if he has a fast accelerating rocket ship he can visit Alpha Centurus and be only a year older when he gets there. But I know that even light takes longer than that to come from Alpha Centarus to Earth and by my clocks, body aging included, it took many years - I am old, so I probably will be dead before he gets there.

It does not slow down. In vacuum light always travel at the same speed, C. What is does is lose energy as it climbs up out of the gravitional well so it becomes "red shifted."

PS James told you the truth. Space time does change, it is not an illusion of change, for the moving guy.

 

Billy T,

Please explain to me how an observer can change another object (space-time) at a long distance without using any energy and doing it so that no one witnesses the change but him?

What if light only travels at c relative to the gravitational field that it is moving through?

 

And I say you should pull your head out of that dark smelly spot and actually respond to the very real issue created by your pet theory; rather than pretend to talk down the messengers with your ethnocentric view of yourself..

 

Because one measure distance with meter sticks that are not moving wrt one'self I.e. his co-moving meter sticks are not any shorter for him, but the separation for Earth to Alpha Centarus is less, contracted FOR HIM ONLY so it takes less of his still normal meter stick laid end to end to measure that distance. Perhaps 1234567689 of the meter sticks will reach between and I agree on that number as each of them is moving wrt to me and only a few cm long compared to my stationary meter sitcks.

For years an "either" was postulated to be the answer. It has stange properties, no mass, makes no gravity, is never seen, does not remove any energy as the Earth moves thru it to orbit the sun. It rapidly passes thur inch thick steel walls of a vaccum tube, faster than the air can be pumped out, etc. but if light was a wave in the either, then sort of a Doppler effect should occur* as the earth is moving the oppsite way from any star every 6 months and the direct the light seems to coming from changes like when you running thru rain drops changes their approach angle (see more under "stellar aberation") etc. Many tests all failed to show any effect of the postulated either.

Maxwell's equations give the speed of light by meauring only two electric and magnetic proberties of the vacuum. This too shows that nothing is required to be the "medium" in which light propagates. Sound waves need a medium. do not progate in vacuum, but light can and does. - The sun is shining now for me - that is also proof.

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*The "either believers" said no - the Earth drags, without energy loss, the local either with it as it orbits. That is why the stellar aberation experiments were needed to close that "escape hatch." Either is just inconsistent with experiments - does not exist.

 

Billy T,

What if light doesn't have a medium or aether, but is pushed by gravitational fields?

 

The correct answer requires you know some tensor math and GR theory, but I would somewhat incorrectly answer: Gravity "warps" space.

 

Physicists know relativity is not an 'ultimate theory', that it's almost certain something will come along to replace it but that doesn't automatically make you right in your particular criticisms. Your example of accelerating giving length contraction giving shorter distances isn't a problem, you might not like it because its counter intuitive but that doesn't mean relativity is wrong or flawed, it just means that some things in the universe don't behave in the same way as everyday physics does.

Quite frankly I'd be amazed if there wasn't counter intuitive phenomena in the universe, given intuition is just our way of saying "I expect things to follow my experience" and our experience of the universe is tiny.

 

Which makes such differences a matter of "Perception" not physical reality.

i.e. - The reality is that given two clocks that are synchronized at common rest and one accelerates away while the other remains at rest; both share a "Relative Velocity" and both "Percieve" the other as dilated; the fact turns out when comparing them subsequent to having had relative velocity is that ONLY the one accelerated clock is dilated.

Without question this means "Relative Velocity" perse' is not a cause for physical change. That leaves the question what was different for the dilated clock. The difference is that it accelerated and changed velocity in an absolute way.

i.e - It was subjected to a = m/F which induced v= at. It has "Actual Motion" to the common rest frame vs "Mere Relative Velocity".

That is why SR applys the "Frame Switching" standard. Frame switching only occurs via acceleration.

No what is absurd is that relativist refuse to acknowledge the obvious and that is Einstein's SR only describes "Illusions of Motion" and physicists today actually use LR , a preferred frame view which eliminates the inherent symmetry of SR to predict results but then claim it is SR.

Totally false. I have repeatedly said what is being done is fine and useful mathematically but they need to simply acknowledge the truth and that is "Relative Velocity" is not a cause for physical change.

If they did then perhpas those that are looking for the "Why" would get more attention rather than being baggered and labled by the believers.

I appreciate your acknowledgement of my past although I don't see that an issue since the issue is "Relative Velocity" and if what I'm saying is true then my education and experience or achievements have no bearing on the issue.

 

I know this is meant for Billy, but I thought I'd take a stab at this

1) What benefit is there to considering light to be a gravitational effect? How do you use gravity to calculate its speed or wavelength? Can you actually describe anything quantitative about the real world through this approach?

2) Why is the speed of light in vacuum always the same, whether it's measured by labs on Earth or satellites in space? Why do signals from Earth to space and space to Earth always travel at c? Doesn't seem like gravity makes any difference here.

 

No I don't like it and point out just how ludricrus the consequences are to stipulate a clock is dilated (which physiclly bears out emperically as well) but when in the dilated frame disregard the lower tick rate just because the traveling observer's time standard precludes him from knowing his 1 Second is longer than the resting 1 second when directly compared.

Because doing so you are switching time standards in an absolute way and the fact that the dilated clock accumulated less time for a trip compared to a resting clock you must now claim distance changed. Whereas if you merely retain the physically dialted status of the traveling clock then the accumulated time is only correct if distance did not change.

Your arbitrary mathematical formalisim creates the contraction but it has never been measured, observed or produces any permanent change physically. Time dilation does. Contraction is merely an artifcact of an ill concieved physical concept.

Eliminating spatial contraction eliminates numerous "Counter Intuitive" issues without altering the final results of relativity.

I fully agree but there is a large difference between something being physically "Counter Intuitive" and being "Physically Impossible". For James R (or others) to suggest that the observed mutual dilation between to clocks with relative motion is physically real and not merely an "Illusion of Motion" is assinine.