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| Veritasium -- How Special Relativity Makes Magnets Work. |
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| aetherist:
--- Quote from: hamster_nz on April 15, 2022, 08:44:27 am --- --- Quote from: aetherist on April 15, 2022, 06:27:46 am --- --- Quote from: hamster_nz on April 15, 2022, 12:43:44 am --- --- Quote from: aetherist on April 14, 2022, 07:52:48 pm ---Einstein's slowing of light near mass... --- End quote --- I expected you to pick your words more carefully... --- End quote --- I am not sure of Einstein's exact wordage, ie the English translation. But in essence it was that light slows near mass. I dont think that he said photons. Or em radiation. --- End quote --- I was more thinking about "slowing" rather than the "light". I just thought you would have used "light takes longer to travel" as the speed of light in vacuum is a constant. --- End quote --- Aetherists mostly believe that the speed of light is constant, c, in the aether. They are wrong. Einstein said that light is slowed near mass, ie if in a gravity field, as proven by Shapiro. Einstein was wrong, partly, possibly. I have explained that light is slowed by gross gravity, not nett gravity. So, i would have to ask Einstein whether his equations should apply to gross gravitational potential or nett. If he said gross, then i would say that he was correct. In the instance of radar & Venus gross & nett are the same thing (very nearly), hence Shapiro didn’t have to decide tween gross & nett. Not that Shapiro was aware of the problem. And i can add that Shapiro's equation was fudged. I think that Einstein's field equations always have to be fudged, at least a little. I clearly remember a paper that Einstein wrote where he explicitly said that in GTR the STR naïve statement that the speed of light was constant did not apply. Unless the lab was far away from any mass, which is impossible (my words). He might have used the words 'in distant space'. English translation of course. Its difficult to know whether to say "light takes longer to travel", koz nothing is real in GTR, all such things are only apparent. Each observer has her own spacetime. Light appears to take longer. Light appears to bend, etc. Einstein said that a half of the slowing was due to time dilation, & a half was due to space (length contraction). Wrong. Time dilation duznt exist. Length contraction is true, but has no effect on slowing. When i say length contraction is true, i mean neoLorentz length contraction (ie due to aetherwind), not STR length contraction (due to relative velocity). Slowing is due to photaeno drag, which i won't go into today. I believe that the slowing of light might accord with the standard equation for gamma. U insert the escape velocity in the V in the VV/cc. |
| aetherist:
Herr has a nice summary of variance & invariance in STR, with of course the usual STR assumptions & suppositions elevated to the better sounding postulates & principles & laws, & the usual lies & lack of good logic. https://cds.cern.ch/record/2674125/files/337.pdf Short Overview of Special Relativity and Invariant Formulation of Electrodynamics W. Herr CERN, Geneva, Switzerland Abstract The basic concepts of special relativity are presented in this paper. Consequences for the design and operation of particle accelerators are discussed, along with applications. Although all branches of physics must fulfil the principles of special relativity, the focus of this paper is the application to electromagnetism. The formulation of physics laws in the form of four-vectors allows a fully invariant formulation of electromagnetic theory and a reformulation of Maxwell’s equations. This significantly simplifies the treatment of moving charges in electromagnetic fields and can explain some open questions. 9 Summary 9.1 Summary—relativity basics – Special relativity is very simple; there are a few basic principles. – Physics laws are the same in all inertial systems. – The speed of light in vacuum is the same in all inertial systems. – Everyday phenomena lose their meaning (do not ask what is ‘real’). – Only the union of space and time preserve an independent reality: space–time. SHORT OVERVIEW OF SPECIAL RELATIVITY AND INVARIANT FORMULATION OF ELECTRODYNAMICS – Electric and magnetic fields do not exist! – They are simply different aspects of a single electromagnetic field. – The manifestation of the electromagnetic field, i.e., division into electric E~ and magnetic B~components, depends on the chosen reference frame. |
| TimFox:
"Consequences for the design and operation of particle accelerators are discussed" Last I heard, the major particle accelerators (CERN, Fermilab, DESY, etc.) work well when following this process. |
| aetherist:
--- Quote from: TimFox on April 17, 2022, 02:04:24 pm ---"Consequences for the design and operation of particle accelerators are discussed" Last I heard, the major particle accelerators (CERN, Fermilab, DESY, etc.) work well when following this process. --- End quote --- Today i have been looking into invariance, ie re inertial frames. Einsteinists suppose that some things are invariant, i think charge rest-mass c etc. I wanted to see what Lorentzists & neoLorentzists (ie aetherists) reckoned. But no luck, they dont say much re charge rest-mass c etc. I think that almost everything changes with velocity, at least a little. A different velocity means a different aetherwind. Aetherwind gives length contraction. However, this length contraction applies equally to the object in question & to the measuring rods, hence we have Lorentz invariance for apparent length (ie for perceived length). But, we don’t necessary have Lorentz invariance for apparent distance. For example, if 2 spaceships, one following the other, joined tail to nose by a tight weak string, were to accelerate, then an aetherist would say that the string would break, koz the 2 spaceships & the string all length contract. The real distance (gap) tween the 2 spaceships dilates as the spaceships accelerate & contract. And the apparent gap dilates (ie it appears to be larger)(koz the measuring rods on the spaceships suffer length contraction. The real distance & real mass & real anything are what is seen by an observer in the rest frame, ie in the absolute frame, ie where there is zero aetherwind. Re the spaceships & string. I should have said that the spaceships have a headwind. If they initially had a fast tailwind then as they accelerated their real lengths, & the real length of the string, would all dilate (get longer), & the string would slacken (at first)(ie the string would not contract). But the real gap & the apparent gap tween the spaceships would shorten, & the apparent length of the string would shorten. This kind of length contraction & real length variance or apparent length invariance are a no-brainer. And real anything is a no-brainer. But, apparent anything can get complicated. I have never thort about this very deeply. It makes my brain hurt. The apparent say force might be measured a number of ways. Each different way will involve a different apparent result. Measurement might involve a standard mass, or a standard spring, & praps a clock of some kind (eg atomic, or balance wheel, or quartz, or pendulum etc), & praps a say rod. The ticking rate of every kind of clock etc will be affected in a different way by length contraction. Some clocks might tick faster rather than slower. Time has no effect (on the measurement of force), there being no such thing as time, or time dilation. What we have is real ticking, & apparent ticking. Whether mass force charge temperature etc etc have certain real values & certain apparent values (in moving frames) is complicated. The answer has to be that everything is apparently variant, nothing is apparently invariant. Even the length of our rods is variant, both in the real sense & in the apparent sense. Its like this. The length contraction of an object depends on the size & shape of the elementary particles of the object, & the em forces within the atoms & molecules, & the em forces tween the atoms & molecules. Different substances will have different kinds of em forces acting, or i should say the same kinds of em forces but acting in different ways. Hence every object, every substance (eg steel rod)(wooden rod), will have its own gamma for length contraction. And, as i already said, that there gamma will depend on how u measure, eg it will depend on your choice of measuring instruments. Some things will be less apparently variant, ie almost apparently invariant (especially if one uses very standardized instruments)(or instruments designed to give a less variant result). But i don’t know what these things might be (eg mass, force, charge, temperature etc). Still thinking. |
| PlainName:
--- Quote --- then an aetherist would say that the string would break, koz the 2 spaceships & the string all length contract --- End quote --- Really? My simplistic understanding is that for speed of light to remain constant, for the observer in the static reference the spaceships (and string) must appear to contract, otherwise light in the moving reference would either be slower in the moving reference or seem to be faster than the speed of light from the static reference. The contraction allows the speed of light to be constant regardless of reference. But then it also follows that the distance between spaceships must also appear to contract, otherwise light passing from one ship to the other would seem to slow in the moving reference. Alternatively, if it remained c in the moving reference it would seem to be faster than c in the static reference. Thus the space contraction. So the space contracts exactly the same as the string, and the string doesn't sag or break. I think your problem with this is that you apply contraction (and similar) to physical entities rather than the reference in which they reside. Of course, I am not a physicist nor a scientist in any shape or form, so I could be as massively wrong about this as you. Happy to be put right by someone in the know. |
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