studiot

Presumably you keep the fire going under the same conditions you light it, wet or dry, rough or smooth.

OK try this Which is it easier to do? Light the fire in the grate Keep the fire going once you have a roaring fire? Which is a 'more complex' fire, the initial lighting or the fire you toast your sausages by? Same with a car or an outboard engine or a mower, is it easier to start the engine or run it once it is going. It's getting started that's the hardest.

You still haven't appreciated my point, and I am somewhat at a loss how to put it differently. Equally I have no idea what you mean by relatively (other than the pun)? But my point is that I don't like draw inference about the comparative greatness of A v B from what they did in vastly different circumstances. I tried to give some examples from other walks of life. For instance how do you compare the greatness of an amateur runner on an average day on an average track of the 1950s with The greatness of a modern professional runner equipped with very high tech clothing, training, diet, and energy return running track? With respect, I honestly don't think you know enough to properly discuss complexity or new maths in that context. If I use the long known Wallis formula to calculate pi to a trillion places have I done new or complex maths? How about If I use Green's theorems to solve the energy flux in an engineering structure? This would be an unconventional but feasible solution, is it therfore new maths? It would be a very complex way of going about the subject, at least as complex as anything Witten has done. We like simplification in Maths, which is why Witten has the advantage over even Einstein, let alone Newton, of group theory. During the 20th century group theory has come to the fore and pointed, particularly particle physics but many other areas as well, in the correct direction for further research, experiment and simplification/rationalisation of Physics. He has truly stood on the shoulders of all the giants who have been involved in the linking of maths, previously thought just abstract, with the material Sciences.

Right on the button +1 You have totally missed my point. Newton introduced the inverse square law and had nothing (mathematically) whatsoever to look back to. (despite the giants stuff). There are all sorts of Newton's equations for this that and the other (eg in fluid mechanics, heat etc) Witten has all the preceeding maths to work from. Of course modern maths makes much of Newton's stuff look simple, but the greatness was in the ideas. BTW I'm not a fan of Witten's hypotheses, what fundamental maths has he introduced?

This is one basic definition for differentiation that leads to many standard derivatives. But it is not perfect, and there are other representations. However I don't want to confuse you if you are just starting to study calculus in general and differentiation in particular Can you please tell us a bit more background to your question. So I will just say for the moment that it does not cover all cases. Consider the functions 1) [math]f(x) = \left\{ {f(x) = \sin \left( {\frac{1}{x}} \right)} \right\}[/math] F(x) is not even defined at x = 0 2) [math]f(x) = \left\{ \begin{array}{l} f(x) = x\sin \left( {\frac{1}{x}} \right)\;:x \ne 0 \\ f(x) = 0:\;x = 0 \\ \end{array} \right\}[/math] This one is continuous at x = 0 , but still not differentiable there. 3) [math]f(x) = \left\{ \begin{array}{l} f(x) = {x^2}\sin \left( {\frac{1}{x}} \right)\;:x \ne 0 \\ f(x) = 0:\;x = 0 \\ \end{array} \right\}[/math] This one is both continuous and differentiable at x = 0 4) [math]f(x) = \left\{ \begin{array}{l} f(x) = 1:x\;is\;rational \\ f(x) = 0:x\;is\;irrational \\ \end{array} \right\}[/math] f(x) is nowhere continuous, or differentiable

Does it? Much as I don't like comparing people from different eras such as Louis and Lewis, Bannister and Geurrouj etc, I will compare Newton and Einstein. Newton's work is definitely simpler for us, but was it simpler for him? Not only did he have to invent the Physics, he also had to invent the Mathematics to express it. Not even the equation had been invented in Newton's day, he dealt in proportionality. On the other hand although Einstein put forward some outstanding Physical insights, he developed no new Mathematics.

Having been dismissed as the voice of accuracy and reason by that of fantasy and self delusion I will go and do something useful like checking on my single malt stock until you can post the procedure for turning lead into gold. Bye.

Yes, really. Perhaps you could cite the paper in which Lorentz predates Einstein to that world shattering proposition. Lorents introduced his tranformation following his famous experiment as a possible explanation for the null result. This explanation had nothing to do with the speed of light. But perhaps you prefer to base your hypotheses on fantasy history. Common sense should suggest to you that there must be something behind what I am saying or I wouldn't bother to mention it. It makes no difference to me who first stated the Lorentz transformation, I ask again, why do you think it is called the Lorenz tranformation not the Einstein transformation? This is the ultimate in pig headedness. Are you then denying all the quotes in your previous posts on this subject? Would you like me to list them as forum quotes and formally count them?

I didn't use any other materials, except the movie, which explains the Lorentz transformation and time-space diagram for frames in motion (what makes the base of SR) Nonsense, you must have listed a couple of dozen web and other references. Please keep to verifiable truths. Again you don't know what you are talking about. Why do you not respond when you are offered correct historical records?

Sorry but, this is entirely symptomatic of someone who only takes his material from cranks. If you listened to respectable workers (like here) or read respectable publications you would know the real history of Lorenz and his transformation.

Yes Zapatos, I got the pun and the sense. +1 Thanks fir the reply. +1 Ghideon, thought about putting in something about modern day collective activity. Thanks for brinking it up +1

1) If you put one tenth the effort into studying that book you put into finding junk science on the internet you would be very knowledgable on the subject and able to answer simple questions about claims you make unlike (2) below. 2) That was not an answer to my question , although you obviously thought about it and shied away. This was because velocity, constant or otherwise, is immaterial in relativity. The only thing that matters is relative velocity. Funny how they call it relativity isn't it? My question was, of course, designed specifically to bring this point out. 3) Hearsay evidence is not allowed in a court of law, and the standard of evidence required in Science is far greater. This is why the good folks here reject all this hearsay evidence you cannot support. Since the authors of your references are not present to answer for themselves, you must be prepared to stand in and substantiate them yourself. 4) I note you posted the same question as the one in your recently closed thread on another Physics site. I didn't think it possible but a well respected senior member there gave you an even more cogent and easily digestible answer than Janus did here. 5) Did I mention that book by McComb? When you read it you will soon see that you can't add opposing velocities in the manner you just proposed two posts back. Mechanics does not work that way.

To help you understand, answer me this one simple question. In a universe where SR applies but there is only one frame, how fast does time flow, does it matter how fast that frame is moving? In relation to that closed thread, I had quite a detailed post prepared, but I lost it all as the thread was closed. Here is the info as well as I can remember. Looking at your responses it is clear you are not fully up to speed on classical (pre relativity ) mechanics. You cannot hope to understand the finer points of Relativity without this knowledge. Here is an Oxford University book that treats classical mechanics and then moves into SR and elementary GR in a way that is accessible to someone with high school Maths and Physics. It introduces briefly but does not use the more esoteric notation such as Einsteins's summation notation, contravariance and covariance, tensors, forms and metrics. But it does not launch directly into a series of definitions about these and then densely obscure the rest of the book with them. Also it comes fully and reliably verified, unlike many of your references. I believe it has a simple derivation of the repeated Lorentz transform we were discussing. Dynamics and Relativity W D McComb

Thanks for the replies. Here is my take on it. Looking back over the centuries, there were a very large number of cases where the result of a practical experiment overturned conventional wisdom and thinking. Sometimes the experiment was actually an accident as with Rutherford and the nucleus. Sometimes the experimenter was up to the job of explaining what happened, as with Ruthrford, sometimes not as with Hertz and the photelectric effect. The Great Men of their day were therefore more often than not forced by practical experimental results to particular conclusions, rather than by prior theorising. So if and when Einstein is superceded, it may well be a practical anomaly like the one that led to Relativity in the first place, or the Quantum theory or the structure of the atom or........ Einstein's greatness was that he realised the significance of the results, as did Newton in his time, and Maxwell in his. However you don't need to be so great to perform the crucial experiment, just a first class technician.

It's coming up to midnight here. I will see what I can look out tomorrow, but I am old fashioned so I tend to regard references as in books or papers. Janus would probably have this stuff at his fingertips. This is not a personal criticism, but your guess underlined above suggests you are not up to speed on classical mechanics. You really can't hope to cope with relativity unless you can do that first, except in the most general terms which will leave much important stuff out. In those circumstances you need to be a bit less ready to jump to unjustified conclusions. You should not have to guess at fundamentals. I have already just told you that kinetics or kinematics has nothing to do with forces (although it deals with accelerations, boosts and so forth).

Are you sure? Have you looked at my topic in the lounge? That's much better, and much closer to what I originally said to you. But I also said that applies to anything else that is referenced to your frame ie within your frame. But why only constant velocity. The Lorenz transform has the (interesting) property that the L tranform of a L transform is again a L transform.

Only in part. In elementary mechanics, we start with kinematics, whcih is purely about equations of motion, irrepective of how those motions are caused. In particular kinematics does not involve any forces. To do this we move on to a more complete description, known as dynamics. It is much the same in SR and GR Forces are not involved in SR, but introduced in GR. So yes, GR deals with gravity (in its own way) Now I have answered you how about going back afew posts and answering my comment on stationary observers?

A point of proceedure, John You have to highlight that text in order to copy it. If you stay your hand a bit longer to get the "quote this " up we will know whom you are responding to.

Well there you have my question for discussion. Do you have to be cleverer than Einstein to disprove his theories?

I seriously suggest you start by clearing up this misconception. What you are referring to (perhaps) is what used to be called 'the laboratory frame', which was often considered stationary

Yes indeed. But Janus, please you are wearing out the +1 clicker on my mouse. I would just like to add what Mordred hinted at. John, I think you are confusing reference frames with your light clocks. If they are mounted in the moving frame (as you state) they do not experience length contraction in relation to that frame. Observers external to that frame observe the length ocntraction/ time dilation.

Well that may have been the beginning, but I'm not stuck nearly 50 years ago. Since that time we have had satellites eg NASA GP-B experiments, but my knowledge of these is far from encyclopaedic.

As a matter of interest I am banging on about this for a very good reason. We don't have the technology to perform the experiment you describe and confirm with actual measurements. However we do have the technology to take two clocks, running as identically as possible, leave on eon Earth and take the other for a few trips round the Earth at speed. This experiment has been done many times now and always confirms the predictions of SR. Indeed, Swansont makes his living from it, and look how well he lives. If you ask him nicely he will probably know the record for the biggest and smallest differences ever measured.

Isn't that a bit like asking the best recipe for curry? You haven't said where you are starting from, or any other relevant detail, so start here https://ocw.mit.edu/courses/physics/8-04-quantum-physics-i-spring-2013/lecture-videos/