Michelson-Morley experiment interpretation and relativity

Hi,

I recently started watching (a couple minutes anyway) of "The Inexplicable Universe" starring Neil deGrasse Tyson, and near the beginning of the first video (on netflix), he is describing the Michelson-Morley experiment which was done to try to detect the variance in the speed of light due to the orbital motion of the earth around the sun.

The experiment came up with a null result meaning the detected speed of light was the same, and earth's velocity could not be determined by doing this measurement.

Lorentz's relativity explains this null result by assuming the measuring equipment undergoes length contraction in the direction of motion, whereas special relativity by Einstein, directly takes the result from the experiment and says that light travels at the same speed in all reference frames, thus negating any background reference frame.

Neil deGrasse Tyson says the Lorentzian relativity length contraction was a desperate attempt to hold onto the aether model of classical physics, however nowadays it makes perfect sense to imagine length contraction associated with relativity.

Einstein's special relativity postulate that light travels the same speed in all reference frames, is a mirror image of Lorentz's relativity postulate that it is not possible to determine the motion relative to the fixed reference frame of the non moving aether.

Einstein's special relativity is an over simplification of Lorentz's relativity, it eliminates the intuitive classical description of propagating waves and replaces it with a postulate of light traveling at the same speed in all reference frames. Lorentz's equivalent postulate that it is not possible to determine the motion relative to the fixed reference frame of the aether, is however backed up by a descriptive explanation based in physical reality of wave propagation and length contraction under motion, and infers that matter itself has a wave nature in order to physically explain the length contraction. For this reason alone I think Lorentz's relativity is a preferred description of relativity compared to Einstein's special relativity, but also if the two model's are followed I think Lorentz's relativity leads to a more intuitive understanding of physics in many other ways, such as not believing in a discrete "photon" but instead seeing a "photon" as a unit of quantum energy transfer with matter.

The people being educated about physics are done a disservice by not learning a physical based model of relativity when one exists.

cheers, Jamie

The idea that light is a wave in the aether was solid scientific dogma until experiment proved otherwise.

It's all Jiggley things flying around.

Cheers

Hi,

I don't think any experiment has been done that has results that make sense 100% and at the same time give evidence that light isn't a wave in the aether :)

cheers, Jamie

I don't know why you say that. Around the turn of the century (114 years ago, not 14) there were only a few unexplained mysteries left in Physics. One was the Michelson-Morley experiment and another was the photo-electric effect. Einstein himself was the person to first understand that light could exist as particles. From Wikipedia, "This discovery led to the quantum revolution in physics and earned Einstein the Nobel Prize in Physics in 1921." I don't usually quote Wikipedia as it should not be considered a primary source, but in this case the quote has a reference to support it.

Is this not sufficient evidence to show light isn't a wave or do you have some understanding of wave theory that the rest of us don't which explains the photo electric effect?

BTW, no one has ever say (and been correct) that light does not behave like a wave. It can behave like a wave or behave like particles. Just not both at the same time. Regardless, rather than needing to disprove the existence of the ether, it is incumbent on those who support its existence to prove it. Does like need an ether to be a wave?

On a sunny day (Sat, 31 May 2014 17:28:21 -0700) it happened Jamie M wrote in :

Yes, and there are many questions about M&M (not the candy). Look up Mount Wilson.

I am just awake, so not /.. I wondered on sci.physics why it is people do not see that a 'wave' reflected from a mirror is not the same (is in fact re-emitted) as the wave that hits the mirror, causing emission in the local reference frame, or simply a Doppler shift. this also goes for light (wave) passing _through_ glass, what comes out is re-emitted in the local reference frame, again Doppler shifted. So just for that reason M&M _cannot_ see anything, But this simple idea could be wrong.

But then again earth was flat, while every sailor could see a ship going down over the horizon.

I do not and will not bet 1 cent on the validity of todays 'physics', just as little as on the earth water and fire are the basic elements of long ago. I dunno if humanity will survive, or go dinos way, but if they persist long enough maybe some better theories will pop up, that is after all the current parrots who hold peer review positions or are respected because they are cripple and out of pity are given positions (black holes have no hair, and always wrong), are dead. The way it works in my not so humble - but proven by history- view is that large wars do away with crap, crap in many ways and the things that WORK and the ones that use those win.

In the mean time it is safe I think to ignore any invention or paper that has 'quantum', 'nano', or 100% batteries in them. Yes I like the practical, I like for example SpaceX presentation:

LOL

le Universe" starring Neil deGrasse Tyson, and near the beginning of the fi rst video (on netflix), he is describing the Michelson-Morley experiment wh ich was done to try to detect the variance in the speed of light due to the orbital motion of the earth around the sun.

ight was the same, and earth's velocity could not be determined by doing th is measurement.

equipment undergoes length contraction in the direction of motion, whereas special relativity by Einstein, directly takes the result from the experime nt and says that light travels at the same speed in all reference frames, t hus negating any background reference frame.

My understanding was that Einstein's Special Relativity was better way of e xplaining Lorentzian contraction, by embedding it in a more general theory, rather than any kind of alternative to Lorentzian contraction.

a desperate attempt to hold onto the aether model of classical physics, ho wever nowadays it makes perfect sense to imagine length contraction associa ted with relativity.

speed in all reference frames, is a mirror image of Lorentz's relativity postulate that it is not possible to determine the motion relative to the f ixed reference frame of the non moving aether.

It's more an alternative way of formulating the same mechanism than any kin d of mirror image.

relativity, it eliminates the intuitive classical description of propagating waves and replaces it with a postulate of light travelling at the same speed in all reference frames. Lorentz's equivalent postulate that it is not possible to determine the motion relative to the fixed ref erence frame of the aether, is however backed up by a descriptive explanati on based in physical reality of wave propagation and length contraction und er motion, and infers that matter itself has a wave nature in order to phys ically explain the length contraction. For this reason alone I think Loren tz's relativity is a preferred description of relativity compared to Einste in's special relativity, but also if the two model's are followed I think L orentz's relativity leads to a more intuitive understanding of physics in m any other ways, such as not believing in a discrete "photon" but instead se eing a "photon" as a unit of quantum energy transfer with matter.

Einstein became the world-famous physicist, not Lorentz. Physicists general ly accepted Einstein's generalisation of Lorentz's proposal as including Lo rentz's insights in a better theory.

The concept of the photon - invented by Einstein in 1905 - won him a Nobel prize in 1921. Most people who get Nobel prizes have to wait longer. It was a necessary invention. It's a recent idea, and we are still wrestling with the implications. Max Planck got to the guts of the idea earlier - in 1900 - but couldn't bring himself to take it seriously. He still got a Nobel Pr ize for it in 1918, almost as fast as Einstein.

Even if it was superseded very shortly after it had been proposed?

Err... Newton had his corpuscle theory.

Err. not true. Although the wikki article expounds the differing views,

At least one physicist considers the "wave-duality" a misnomer, as L. Ballentine, Quantum Mechanics, A Modern Development, p. 4, explains:

"When first discovered, particle diffraction was a source of great puzzlement. Are "particles" really "waves?" In the early experiments, the diffraction patterns were detected holistically by means of a photographic plate, which could not detect individual particles. As a result, the notion grew that particle and wave properties were mutually incompatible, or complementary, in the sense that different measurement apparatuses would be required to observe them. That idea, however, was only an unfortunate generalization from a technological limitation. Today it is possible to detect the arrival of individual electrons, and to see the diffraction pattern emerge as a statistical pattern made up of many small spots (Tonomura et al., 1989). Evidently, quantum particles are indeed particles, but whose behaviour is very different from classical physics would have us to expect."

Despite conventional descriptions, the real issue is not that light might be a disturbance in an aether, but that there might be a background field to which motion is related to. These are not the same concept, and usually not appreciated.

Dark energy and Dark matter are modern postulates that are made based on explaining observations. Neither has been directly confirmed, yet remain credible in the scientific community.

The speed of light issue is this. Irrespective of whether light is a particle or a wave, if you run (uniformly) into a light source and measure its velocity, the result is always the same. This has no conventional physical explanation.

To achieve no change in velocity it seems that in some way the observers velocity is being exactly compensated out, i.e some compensation factor dependant on the observes velocity. But the observers velocity relative to what?

Special Relativity simply declares that, that is the way it is. It just steals the equations of The Lorentz Ether Theory (LET), and offers no explanation as to why light speed, for uniform observer motion, is independent of that motion.

The essential postulates of LET can still be applied to light as particles, without the requiring for light to be a wave disturbance in an aether. That is, anything moving with respect to some reference background field interacts with it it in such a way that its physics changes to account for the measured results.

So, it can be argued, as in the dark matter/energy case, that a background field is a rational way to physically explain why measurements are not as expected.

Kevin Aylward B.Sc.

Its a "simpler" theory in the sense that it just states some facts, and declares that's all that is required to know.

Sure, but hardly an argument for SR.

In the absence of any evidence at the time for something in the vacuum, an appropriate choice.

He didn't invent the concept of a "photon". However, he was the first to get a corpuscle theory of light to explain certain aspects of light not explainable by the exiting wave theory, or the older corpuscle theories. A new name of "photon" does not change the fact that such ideas have been around for hundreds of years.

It isn't. No one works in a vacuum. No physicists could possible been ignorant of all the prior work on particle approaches to light, and such work clearly influenced the later work.

Standard texts are very biased as to the allocation of credit for ideas. Edison comes to mind.

Irrespective of the merits of the LET theory, I agree that knowledge of what led to SR is very useful.

Einstein simply took a prior complicated deduction as a first principal. He was, apparently, the first to appreciate that all the prior work and LET equations that were already known to be correct, could be simplified by simply assuming that the speed of light was invariant. In fact, it was a "light bulb" moment. From a formal point of view, he appreciated that there was no technical gain to be achieved by "understanding" physically why light had the properties that it had. Its shut up and calculate.

However, one can not ignore that, essentially, the entire content of SR was known several years prior to Einstein's 1905 paper. Einstein's fundamental approach was to produce the identical known results, but in a clearer way. In fact, in the similar way that I produce the same correct Delta-Sigma noise equations, that are universally derived in existing treatments clearly nonsensically (

useful reading is:

I think its highly unlikely that light is a wave disturbance in an aether, however its also pretty much a fact that the vacuum is not empty. It is conceivable that interactions with the vacuum might give a physical basis for the properties of objects in motion. It is also conceivable that there is no deeper understanding.

Kevin Aylward B.Sc.

Mach's point was that the properties of objects in motion can only be under stood in terms of their interactions with other objects. Inertia is a prope rty of the rest of the universe, and is directly explicable in terms of Lor entz contraction - if you've got a lump of mass to move faster, Lorentz con traction means that it's closer to the rest of the universe and its gravita tional potential energy has increased, giving you a neat way to get a weigh ted sum of the mass of the rest of the universe.

Gravity itself needs a bit of deeper understanding ...

A nice idea, unfortunately, Mach and Einstein were wrong. There is a lot of pissing about by some in General Relativity trying to salvage the idea, that Inertia can be attributed to all the other masses in the universe, but the reality is, formulating 20 different versions of "Mach's Principal" to try and get agreement for some of them, means the idea is dead.

Realistically, there is no credible explanation of inertia today. I personally like the interaction with the ZPE of the vacuum idea.

Once I become acquainted with the fact that one can take a spin 2 graviton particle and do all the usually exchange of momentum stuff and derive the Einstein Field Equations, curved spacetime geometry was also dead for me. Its just a descriptive model that isn't actually real. Particle exchange theories work, and no one has managed to describe the other standard particle exchange forces in terms of geometry.

Kevin Aylward B.Sc.

"Credible"... not to me. Dark matter does not have to be anything fundamentally different about the universe. It can just be matter that we have not detected. At the cosmic level I am sure there are many things we have yet to discover.

Dark energy is something postulated to account for a missing term in an equation and currently would require a new understanding of basic physics. I think this is, in fact, an indication that, just as when the Michelson-Morley experiment was conducted, we don't fully understand the problem, much less the solution. I feel that another paradigm shift is soon to be discovered to account for this.

That is because the phenomenon can be understood without "explaining" why it happens. Making up "stuff" is not part of science. "Why" do opposite charges attract? I've never read a reasonable explanation of "why" any of the basic facts of physics occur. Yet, we accept them and make use of them by understanding them.

Except it fails the most fundamental tests of science, Occam's razor. In other words, don't make up stuff when it is not needed.

This comment says it all to me. EVERYTHING in science is just a descriptive model. Do you really believe that we "understand" anything? No, we can predict the outcome of some experiments. Tomorrow we will be able to predict the outcome of more experiments. None of this means we "understand" the universe... as if "understand" had any meaning. We just model the universe as best we can.

Yes, Feynman admitted he didn't actually understand what he was talking about "is." This can be called the ontological question. In science, ontology refers to physical existence, but in psychology or theology, it refers to the question, "Who am I?" It's interesting that hoomans can't answer either area definitively. :)

This might have been just a certain focus in the history of science. It's a lot easier to describe how things work than to say what they are. Theories of gravitation were stalled 1000 years by inability to say how gravity could act at a distance. Then Newton ignored that issue, and just described behavior. You could say all modern science is a conspiracy to give the impression that science grasps the deep meaning of reality, when it is just adept at manipulating it.

This recalls the writings of the Chinese philosopher Chuang tse. He had a monkey called "know how" who engaged in many foolish antics.

It's interesting "who we are" cannot be described by the mind. There is even a Greek theory (was) that demons are those who have no real existence, no "I am" nature. So, Jesus, in his episodes of casting out demons, would ask, "Who are you?"

In these writings about the speed limit of light, The EPR paradox has not come up.

The "dark matter" fills both the universe and our beings...

jb

ether, however its also pretty much a fact that the vacuum is not empty. It is conceivable that interactions with the vacuum might give a physical bas is for the properties of objects in motion. It is also conceivable that th ere is no deeper understanding.

understood in terms of their interactions with other objects. Inertia is a property of the rest of the universe,

of pissing about by some in General Relativity trying to salvage the ide a, that inertia can be attributed to all the other masses in the universe, but the reality is, formulating 20 different versions of "Mach's Principal" to try and get agreement for some of them, means the idea is dead.

No, but it does mean that the 21st version will have to be particularly con vincing if it is ever to get published. Gravity definitely needs a better i dea than anybody has come up with so far - it's going to have to be quantis ed at some level, and nobody yet seems to have put up anything that can be made to work properly.

Hi,

The photo electric effect says nothing about the light whether it is quantized as photon's or is a classical wave, it only shows that matter (electrons in this case) are in quantized states that are frequency dependent. Simplifying this into saying there are "photons" with energy hf works, but it is an oversimplification assuming that quantized matter is what defines the nature of light. In a situation where light is interacting with matter without quantized states shifting then this model breaks down, and a classical description of light is required.

The classical description of light works in both cases, but the quantized description of light doesn't.

cheers, Jamie

You clearly don't understand the issues. A wave has energy depending on its amplitude only. The photoelectric effect found that intensity of light of insufficient frequency would not dislodge electrons from an atom regardless of amplitude. This can only be explained by light existing in packets with an energy proportional to the frequency.

If you have an alternate explanation you should publish a paper and become famous.

Hi,

It can also be explained by classical light being absorbed in "packets" by the quantized system with an energy loss proportional to the frequency, and the energy loss will be in a reduced amplitude of the light. This is because even if the classical light is of a high enough frequency, it still will not cause a photoelectric effect unless its intensity is high enough, therefore the intensity goes down when the photoelectric effect occurs.

cheers, Jamie

I suppose if you are going to make stuff up, you can use any rules you wish. The problem is that in a particle theory there is no amplitude below which interaction will happen, only a threshold frequency. In a wave theory there is a threshold amplitude but not a threshold frequency.

Ok, I can't make sense of this. The observation is just the opposite, no interaction until the frequency is high enough. If the frequency is not high enough there is no amplitude that will result in an interaction.