You claim: "Entropy still exists for systems out of equilibrium".
I'm sorry but that is simply not true. The sun has negative specific heat and that's allowed because the 2nd law simply doesn't apply. It only applies for isolated systems in equilibrium. Check any textbook.
Sounds waves don't have this property. Their speed measured by some observer depends on the speed of the source and the observer relative to the medium of propagation (like the air).
Sean,
You wrote: "Sounds waves don't have this property. Their speed measured by some observer depends on the speed of the source..."
Are you sure? An undergraduate would fail the exam for this.
Pentcho Valev
Sean & Flavio
Speed of sound depends on speed of source!? I've just picked myself up off the floor, and am still wondering if you're serious! Sure the detected absorbed wavelength thus the frequency depends on the source speed.
I agree there is also a case of course where the observer/detector is in the same frame as the source, and the speed is calculated by using coordinated clocks, but in this case we have to ask speed wrt what, so we need a background frame, and then the calculated speed would be inverse to the source speed (with no Doppler shift on detection. I struggle to think you considered this case as, simply, nobody does. Can you explain?
Nicely written and argued essay all round with some interesting views. Well done for getting to the top, hold on for the sleigh ride!
I agree with your point that; "The measurement problem results from the fact that quantum mechanics is a framework more like statistical physics than classical mechanics." And have offered a solution to this via a mechanism in my own essay, which I hope you will read.
I look forward to your comments.
Best wishes
Peter
They definitely have. The speed of sound in air refers to the medium air and has a constant value c that is determined by the medium: about 330 m/s dependent on temperature, humidity, etc. but NOT by the observer.
There is no acceptable reason why this should not hold for electromagnetic waves including light too. There was such reason, and indeed it led first to FitzGerald's and Lorentz's idea of length contraction and later to Einstein's special theory of relativity. Yes, I refer to the failure to explain the null-result of the experiment by Michelson and Morley (MMX). Relativity does not rest on solid ground.
All five Figs. of my essay are compellingly putting basic assumptions in question. Fig. 5 refers to the MMX. Pentcho Valev who favors emission theory calls me an etherist. I would rather say, I merely agree with those who found out that the MMX was wrongly expected to measure the so called aether wind. All of the many implications deserve reconsideration. This will most likely also put the basis of your essay in question. I am sorry for that.
Eckard
With relativity I meant Einstein's relativity. Galileo was definitely correct.
Eckard
Oops, how did the word "source" get in there?! (I'm tired...)
Of course their speed through the medium is constant. All I was trying to say is that if you are moving wrt to that medium, you will have to add your motion relative to this. Hope there is no more confusion!
Sean meant that "the speed of soundwaves depends on the speed of the observer relative to the medium of propagation".
"source" was a slip of course.
I'm reading your essay with interest...
All the best,
Flavio
The speed of the sound/light waves, relative to the observer, varies with the speed of the observer, doesn't it? Is Sidney Redner right?
http://physics.bu.edu/~redner/211-sp06/class19/class19_doppler.html
Professor Sidney Redner: "The Doppler effect is the shift in frequency of a wave that occurs when the wave source, or the detector of the wave, is moving. Applications of the Doppler effect range from medical tests using ultrasound to radar detectors and astronomy (with electromagnetic waves). (...) We will focus on sound waves in describing the Doppler effect, but it works for other waves too. (...) Let's say you, the observer, now move toward the source with velocity vO. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vO. The frequency of the waves you detect is higher, and is given by: f'=v'/(lambda)=(v+vO)/(lambda)."
Pentcho Valev pvalev@yahoo.com
Sean, Flavio,
It may be a very moot point wrt light as well, as you're hopefully finding in my essay.
As the source of sound is NOT also the detector the only way to get a relative speed is by calculation, of c over the flight distance.
Of course it's exactly the same with light when calculated with that same data. That's where the paradox is, because that gives c + v, yet the detector at the end of that flight path, but in the same frame as the emitter, measures 'frequency' (a derivative of effective wavelength on detection) and finds the speed at c/n wrt his lens, not c + v!!
I should say that's where the paradox 'was'. I believe it has now gone using DFM dynamic logic. Because all detectors are made of matter, and all matter is a medium, then all detectors MUST find c/n, because light MUST change speed on arrival to the new local c comply with the constant refractive index n and SR in all frames. (It works the same in a vacuum with scattering off diffuse plasma).
That may need you to lie down with your eyes shut and think through a few dozen times. I've failed abysmally to falsify the model, and found all the apparent issues with it evaporate like the SR paradoxes. Except the human factor of course, as few can overcome it's unfamiliarity. Working at Perimeter may just allow you to not reject it before full testing (I have a stack of test data).
I look forward to your comments or questions (and maybe the look on Lee's face when it's explained to him).
Thanks, and best wishes
Peter
Pentcho.
Correct but incomplete. Like saying; 'music is the variation in sound made by instruments'. It misses the critical mechanism of 'HOW'.
My post below of 20.01 was in answer to Flavio's message above. The fluctuation must have crossed the media boundary (refractive plane) and be propagating within the detector medium BEFORE it reaches any brain cells or sensors.
Old assumption, including Einstein's, was, let's say; 'incomplete'. You might well of course equally say 'wrong'.
Peter
Dear Sean Gryb,
Except for the missing negation you were correct when you wrote "depends on the speed of the source and the observer". Actually, the speed of a wave relates to the medium, neither to its source nor to observers.
This undisputed for sound fact contradicts to Einstein's relativity as well as to the emission theories that are here advocated by Pentcho and by Peter.
The key question is the interpretation of MMX. I am not the first one who understood that the unexpected null-result was actually to be expected. I merely discovered how the outcome of the MMX can be made compellingly plausible and quantitatively confirmed by Feist's experiment.
Please do not lazily ignore these arguments.
I know there are further arguments that putatively confirm either Lorentz or Einstein; in particular Maxwell's equations are not covariant.
Phipps Jr. already revealed that Maxwell's equations were adapted to the (wrong) interpretation of MMX.
Eckard
Let me respond to the many previous responses concerning the interpretation of the Michelson-Morley experiment.
I do not think it is correct to say that one interpretation is "right" or "wrong". An interpretation is an just an interpretation after all. Instead, I think it is more constructive to think of an interpretation as being "useful" or "not useful".
Einstein's interpretation was incredibly useful because it made definite new predictions, like the equivalence of mass and energy (E=mc^2), and because it led to a deeper theory: general relativity, which has been wildly successful.
It is perfectly valid to question the usefulness of a particular interpretation. That is what we are doing with Shape Dynamics and it is part of a healthy scientific discussion. However, for a new interpretation to be useful it must pass the same test as Einstein's: it must make novel predictions and it should lead to a deeper understanding. This is the challenge for Shape Dynamics and it is also the challenge for any alternative view: show how new predictions and a deeper theory could emerge from your interpretation. That is the ultimate goal of physics.
Best,
Sean.
Sean,
Einstein did not interpret the MMX. Allegedly he even denied knowing it.
Almost all physicists of that time including Hertz and Einstein accepted the as now turns out wrong conclusions from the unexpected outcome of MMX.
Whether or not the MMX disproved the aether wind is definitely not a question of interpretation but it can now clearly be decided as either a correct or a wrong conclusion.
Of course, FitzGerald and Lorentz fabricated speculative interpretations of the seeming fact in order to rescue the seemingly disproved aether hypothesis. Einstein built on these ideas his theory of SR. He incorporated length contraction and time dilution into it. Were they ever objectively measured and shown not just to be illusions explainable as Doppler effect?
I do not feel obliged to reiterate the detailed objections by opponents who questioned the ascription to SR of the many claimed predictions and confirming experiments. Some of them were already admitted in the textbook by David Bohm.
I am not the only one who considers in particular Einstein's method of (de-)synchronization and his block universe unreal and obviously flawed. I tend to at best apply the judgment by Ebbinghaus on Georg Cantor on Einstein too.
Even if you are firmly believing in Einstein's SR you might feel challenged to find an alternative explanation for my Fig. 5.
Best,
Eckard
I do not firmly believe in Einstein's SR but I find it extremely useful for solving a wide variety of practical problems and for providing a special limit to an even more useful theory: general relativity. If you have ever used a GPS you have benefited from special and general relativity. Would you discard this remarkable device as readily as the theoretical framework that led to its development?
I would if I had a framework that led to the development of even more remarkable devices. That is what I am looking for (although I will likely fail) and that would be my challenge to anyone who questions the physical assumptions of our fundamental theories.
Dear Sean and Flavio,
Interesting and well-written essay. One quick question: What exactly are the elements of the shape space of your model? Special types of 3-manifolds, I presume? Thanks,
Ben Dribus
Dear Ben,
first of all thanks for the interest in what we wrote!
To answer your question, points of shape space are "conformal 3-geometries" or "conformal 3-manifolds", that is 3-geometries (which are described by 3-metrics modulo 3-diffeomorphisms), modulo local conformal transformations. A conformal transformation preserves only angles but not
vector's lengths, so you can describe a conformal 3-geometry with just the angle-determining
part of a 3-metric. There is quite some mathematical literature on them:
http://en.wikipedia.org/wiki/Conformal_geometry
In our next paper (it's coming soon on the arXiv, stay tuned...) Sean and I found how to describe shape dynamics in the simplified case of 2 spatial dimensions with a Cartan geometry in which
the structure group is the conformal group. You have then a description of the gravitational field
in terms of "conformal frame fields", which are useful for several reasons (in GR it's easier and somewhat more natural to couple fermions to frame fields, and they provide the best known reformulation of GR as a gauge theory). Written in this way, shape dynamics looks like a Chern-Simons theory of the conformal group.
Something about Cartan geometry can be found here:
http://en.wikipedia.org/wiki/Cartan_geometry
Cheers,
Flavio
"If you have ever used a GPS you have benefited from special and general relativity." Really?
Yep.
It couldn't work just with calculations based on Newtonian dynamics.
Look at this:
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps.html
Flavio