The fabric of the cosmos help, time slices help

I'm loving this site but must admit to being a bit of a novice. I'm currenty reading Brian Greene's "The Fabric of the Cosmos" and need a little push in the right direction to help me understand time slices.
The example used in the book to show that two observers travelling relative to each other would not agree on what happens simultaneously uses itchy and scratchy dueling. Itchy and Scratchy are at either end of a moving train with Apu as observer 1 in the middle of the train. Apu lights a flare as the signal to fire. He lights the flare and both Itchy and Scratchy fire. Apu claims this is a fair duel as both Itchy and Scratchy are equidistant form the signal. However, Martin is observer 2. He is on the plat form as the train passes and claims that the duel is unfair as Itchy, who was at the back of the train is travelling towards the signal and therefore sees it first. As Scratchy is moving away from the signal it takes longer to reach him.
I'm almost there but have trouble with the following....

1) Should Apu know that Itchy is travelling towards the flare and if so should he not claim as Martin did that Itchy would see the falre first?
2) If Apu is oblivious to the fact that they are moving relative to Martin but Martin is aware of the train moving relative to him, is it not a matter of observation rather that an actual difference of simultaneoussness (if that's a word?)?
3) The example goes on say that if Itchy and Scratchy set a clock to midday (rather than firing at each other) as soon as they saw the flare, Martin would observe that Itchy set his clock before Scratchy as he was moving towards it. Does this mean that Martin is actually timing what he sees and what would be the result from Apu's postiion?

Any help would be most appreciated. I'm trying not to move on in the book until I have a decent grasp of it.

Hi, sylbaryn - try to consider these applets (1, 2) and/or videos(1, 2). in particular the twins applet, which are explained by the Aether wave theory using the simple model of the wave spreading onto water surface.



I hope it helps You with the further intuitive understanding of spacetime behavior.

Zephir,

I like your videos. Didn't see them the first time that I looked at your reply to my post.

sylbaryn,

It turns out that if all objects are created out of electromagnetic waves, then they behave like waves. The results is that an object responds to motion just like a wave of light. This makes it impossible to detect absolute motion with a Michelson-Morley type of experiment.

If you would like a more detailed derivation of this, you may want to read Section 6 of my book Time, Matter, and Gravity. However, keep in mind that I do not agree with all the concepts of Relativity.

Morris

OK, but don't forget please, the light wave behaves not EXACTLY as the sound wave in air with respect to the object moving in the air!

This simple 3D concept was falsified reliably by the one hundred years ago as the former Aether theory and it makes the main difference between the normal Doppler effect and the relativistic one.



All concepts of relativity theory are correct definitely insomuch, they can be applied even in the hidden dimensions metric recursively - therefore if you don't think so, then you're a definitely mistaken somewhere...

Hello sylbaryn.

The Aether medium of the ‘pseudo-bulk’ (so-called ‘spacetime’---as distinct from the true bulk of ‘space’ ONLY) is a composite medium ranging from infinitesimally ‘fine’ GRAV-INERTIAL FLUID components to variously-scaled ‘course’ ELECTRO-MAGNETIC AGGREGATE components---picture ‘WET CONCRETE’ with its ‘fine’ cement and water-molecule components PLUS all the variously-scaled sands and gravel components. Now let’s for the moment consider ‘perturbation-propagation within such a composite medium as wet concrete. We see that if all perturbations (‘wave-particles/wave-structures’ ) were COMPOSED ENTIRELY OF COMPLEX SOUND WAVE ‘PACKETS’, these perturbations would naturally propagate along the wet-concrete medium at the MEDIUM-SPECIFIC SPEED-OF-SOUND LIMIT OR LESS. Now, since all perturbation structures are COMPOSED OF SOUND-WAVES IN THAT MEDIUM, NO COMPLEX PERTURBATION-STRUCTURE CAN TRAVEL ANY FASTER IN THAT MEDIUM THAN THE SIMPLEST PERTURBATION-STRUCTURE, and NONE can travel any faster than the speed of sound-waves in that medium.

Now instead of the ‘wet concrete’ medium, think of the ‘spacetime’ pseudo-bulk medium. The ‘perturbation-structures’ would be composed of ‘wave packets’ in that medium which counterpart the soundwave-packets in the wet concrete medium, ONLY IN THE ‘SPACETIME’ MEDIUM THESE WOULD BE CALLED LIGHTWAVE-PACKETS (although their TOPOLOGY DIFFERS, both types of ‘wave-packets’ STILL propagate as ‘waves’ at their respective medium-specific ‘speed limit’ within their 'natural' mediums), AND THE MORE COMPLEX THEY ARE, THE SLOWER THAN SPEED LIMIT THEY TRAVEL.

It is important to realise that:-

1) IN BOTH CASES, ANY PERTURBATION/PARTICLE/WAVE-PACKET ARISING FROM THAT MEDIUM CAN ONLY EVER TRAVEL AT (AT MOST AT) THE RESPECTIVE ‘SPEED LIMIT’ FOR WAVE PROPAGATION IN THE RESPECTIVE MEDIUM. Hence, just as the soundwaves-packets in ‘wet concrete’ travel may NOT travel at more than the MAXIMUM ‘speed of sound’ limit for wet concrete, the LIGHTWAVE-PACKETS IN ‘SPACETIME’ MAY NOT TRAVEL AT MORE THAN THE MAXIMUM ‘SPEED OF LIGHT’ LIMIT for spacetime;

2) Once ‘emitted/created’, these wave-packet-propagation modes/velocities are ‘absolutely independent’ of their source (which would necessarily be some MORE COMPLEX/AGGREGATED ‘perturbation-structure’ ultimately ITSELF composed of LESSER ‘soundwave-packets’ like the ones they created/emitted.), and...

3) NO, REPEAT NO, SOURCES (themselves comprising convoluted wave-packet ‘complexes’) CAN EVER TRAVEL FASTER THAN THE SOUND/LIGHT WAVE-PACKETS THEY EMIT because THE SOURCES THEMSELVES ARE COMPRISED OF SOUND/LIGHT WAVE-PACKET AGGREGATIONS.

IN OTHER WORDS, IN WET CEMENT AND IN SPACETIME MEDIUM, NO WAVE SOURCE WHICH IS ITSELF A WAVE COMPLEX CAN OUTRUN ITS SIMPLER-WAVE ‘EMISSIONS’...and since EVERYTHING 'SOLID' IS ELECTRO-MAGNETIC (LIGHT) IN NATURE, everything we can 'observe' must travel at less/equal to the speed of light limit!

NOTE WELL: Obviously, you can shoot a bullet through wet concrete at faster than the speed of sound in wet concrete BECAUSE THE BULLET ITSELF IS NOT A SOUNDWAVE-COMPLEX ‘PARTICLE’, it is essentially an ELECTRO-MAGNETIC or LIGHTWAVE-COMPLEX ‘PARTICLE’; hence its ‘natural’ propagation medium is SPACETIME, not wet concrete!...which is why the bullet’s relevant ‘speed limit’ is the spacetime one and NOT the wet concrete one. I have not even touched on the ramifications for universal speed limits applying to the SPACE-ONLY TRUE BULK ‘lower down’ in the scheme of things!...but we’ll leave that to develop in our TOE project under the...

RELATIVITY, QUANTUM MECHANICS, NEW THEORIES FORUM....TOPIC:
”THEORY OF EVERYTHING BEGUN FROM ABSOLUTE CONCEPT” by RealityCheck.



Now, as to the ramifications/interpretation of ‘wave-in-medium’ effects in a TRAIN CARRIAGE, I can best explain by referring you to explanations which ‘vikki maxfield’ says she found helpful, under her thread in the...

PHYSICS GENERAL FORUM.TOPIC .“question about speed of light”.by vikki maxfield.

I have posted a note to you there so that it’s listed more ‘recently’ for you to get to faster. I hope this helps you too!

Good luck from: RealityCheck

Holy crap.........to me it seems that not one of the posters gave a sufficient answer....so I will take a crack at it Sylbaryn, but I can't guarantee that I will do any better (although I will actually refer to Itchy, Scratchy, Martin, and Apu.)
Ok, so before I start with my explanation, remember the assumptions that the speed of light is a constant, and that the laws of physics are the same in all inertial reference frames (this means that on the platform is not a favored frame compared with the train frame, or vice versa.)

So, Apu, Itchy, and Scratchy are all in the same frame of reference. Apu is half way between to other two (distances are equal) so when he sets off the flair, the light has the same distance to travel in both directions as observed by Apu.
Martin is on the platform, and for him the speed of light is a constant once it is emitted. So he sees light travelling towards Itchy, and Scratchy (lets say left to Itchy, and right to Scratchy). Now, we will say that the train is travelling to the right (to give the same advantage as you said in your post). So Itchy is travelling towards the light that is travelling towards him (in Martin's frame remember - think of it as a head on collision between itchy and the light) but Scratchy is travelling in the same direction as the light but the light is travelling faster so it catches up to him.
What this all means is that if the distance between Apu and Itchy (and Scratchy) is x, then as Martin sees it the light travels less than x to reach itchy, and more than x to reach scratchy, so thats why it is not simultaneous in his frame.

I hope this helps a bit, but I won't feel bad if it doesn't. Relativity is a hard thing to grasp at first, especially without good diagrams.
Anyways, goodluck with your understanding, and keep trying.

I'm just explaining this - see the applets. I need any assumptions.

Hi Steveo!

Just wondering whether you managed to catch the last paragraph of my post, where I also referred sylbaryn to the 'TRAIN CARRIAGE' explanations which vikki maxfield found so helpful in her contemplation of such experimental constructs?

If by any chance you didn't catch it, you might like to read the explanations for yourself, then let me know your opinion...please see under...

PHYSICS GENERAL FORUM---TOPIC .“question about speed of light” by vikki maxfield.

Best regards: RealityCheck.

Sorry, I've not been able to log on for a day or two but all the replies are appreciated. Steveo, I appreciate your relevance but I'll need to set time aside to fully appreciate the other replies. ( I cant get the moving files?)

So, I think I have it. My problem was that Apu seemed to be ignoring Martin and not appreciating that Itchy was moving towards the flare but I now realise the point of the example was that this was Apu's perspective of the flare and the two duelists and Martins perspective included the moving flare (from his perspective) so must also include the moving Itchy and Scratchy (from his perspective). Even if Apu thought Martin was flying past him at speed it makes no difference.

But I'm still not sure what would happen if both Itchy and Scratchy set their mid-day clocks when they saw the flare. Would Itchy really set his clock earlier than Scratchy? If Apu checked both clocks would there be any difference or if the train suddenly stopped in relation to Martin would there be any difference in the clock times according to Maritn?

I think you have it! If Apu knows special relativity he can calculate how much time Martin thinks is inbetween one seeing the flare and the other (he would have to measure Martin's speed relative to the 'stationary' train though.
With respect to the clocks. The action of drawing the gun should be considered the same as setting the clock. If both set the clock as soon as they "see the light" according to Martin Itchy would set his clock earlier because the light would reach him first. If the train suddenly stopped though...that leaves the realm of special relativity because stopping is accelerating (really decelerating) and special relativity doesn't apply to accelerating frames, thats General relativity, and I don't know it hahaha.

Don't feel bad if you don't understand the other replies. I don't feel I truely understand those either (mainly because when I see a post that is much more complicated than the question asked, I skim, then ignore it). They seemed to try and overcomplicate things IMO, which is unneccessary. All of the things they described may or may not be relavent, but not at the level of answer I think you were hoping for. Anyways, glad that I could help!

Thanks for the help. Much appreciated.

The fabric of the cosmos? Is this suposed to be the strings?
It should be space-time as well.

I have another point of view.

How can the emptiness of space-time curve?

You gotta give it substance.
The Aether is the very substance of the universe.

'K...

I see it's a K!!!

Spider One to Spider Two: I can tell you are moving away in your Web Machine, your virbations are getting further apart, and my Web Clock (TOE 1/3 charge triplet's gyromagnetic ratios accurate out to 16 decimal places) ticks slower than yours, it seems. Dream on, we're communicating with twenty to forty times speed of light helical "photon" with these tuggs and pushes along the longitudinal threads, so our delay is less.

Why do Earthling Humans not understand it's not throwing "spit balls" at eacch other, just pulling using their Web Internet Threated Systems (WITS).

Physics flows the laws, if you can find them, spider live by their WITS,

More later, trying to interject some level of mathematics from two day ago post of an article on getting as close to mathematical formulation as one can by writing to, say, "procedures".

The allowed assumptions for a theory starting from "nothing" is ok, but will it end up where it begins, or are we all along for the ride.

Riding off into the sunset, more later, best, rmuldavin