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• Nov 24, 2016

David, you are talking to yourself again. Please, talk to me - not to yourself. Talking to oneself is a futile exercise, while something of value might come from talking to someone else with a different worldview.

I am forced to repeat:

So, if you wish to speak of two modes of activity - absolute and relative - then you will have to define for me the notion of absolute velocity (or absolute motion) without employing (directly or indirectly) the notion of relativity. In other words, take a stand-alone object (assuming that you can imagine such thing as a stand-alone object, to begin with) and define its velocity operationally.

My best.
• Nov 24, 2016

Hi Arthur,
OK. When I say that the translational motion of the centre of mass is only relative, within the context of Galilean relativity, what I mean is that it can be different according to which frame of reference we choose to measure it relative to. Not so however for the oscillation of the spring. The latter is an absolute physical activity which shows up the same, no matter from which frame of reference we view it.

But I do however believe, since I don't agree with Galilean relativity, that the translational motion is absolute too, and measured relative to a physical background medium, even though we don't know the velocity of this medium relative to the laboratory. I further believe that the inertial forces arise from interaction with this medium due to motion through it.

Best Regards
David
• Nov 24, 2016

David, I have asked you: to define for me the notion of absolute velocity (or absolute motion) without employing the notion of relativity (attention: I was not talking about Galilean relativity here - I was talking about relativity, period). I have asked you also to define the notion of absolute velocity operationally.

And you came back with this: But I do however believe, since I don't agree with Galilean relativity, that the translational motion is absolute too, and measured RELATIVE to a physical background medium, even though we don't know the velocity of this medium relative to the laboratory.

Wouldn't you agree that I am justified now to assert that you have failed to define for me the notions of absolute velocity AND absolute motion without employing the notion of relativity.

Please note: you have failed even before we got to the problem of defining the notion of absolute velocity OPERATIONALLY, which is a problem of a higher level altogether, entirely different from the problem of simply defining the notion of absolute velocity in words.

My best.
• Nov 24, 2016

Hi Arthur,

Well it can't be done. Motion can only ever be understood as being relative to something else. But when that something else is physical, it is therefore an absolute effect. The oscillating spring is an example of an absolute, frame independent activity, and it involves relative motion as between the two weights on each end.

But if that something else, relative to which the motion is measured, is an imaginary coordinate frame with arbitrary relative motion, then the motion is not absolute.

The translational motion of the centre of mass is therefore a separate issue from the oscillation of the spring.

Best Regards
David
• Nov 24, 2016

Hi David,

Quote: "Well it can't be done. Motion can only ever be understood as being relative to something else."

Allahu Akbar! Now you are talking.

Quote: "But when that something else is physical, it is therefore an absolute effect."

That something MUST be physical, otherwise we are not talking physics. Otherwise we are talking absolutely barren pseudoscience like STR and GTR of Einstein.

Quote: "The oscillating spring is an example of an absolute, frame independent activity, and it involves relative motion as between the two weights on each end."

There is no such thing as frame dependent physical activity. In fact, that's what the concept of relativity is all about, when understood and used properly: Physical activity does not change with the change of the reference frame we use to describe that physical activity. And that is a powerful concept. I do not see how this concept can go wrong ... provided that we keep our guards up against "Einsteins".

Quote: "The translational motion of the centre of mass is therefore a separate issue from the oscillation of the spring."

I do not see any principal difference between the two. If you want to call them both absolute - that is fine with me. If you want to call them both relative - that is also fine with me. But, for God's sake, don't say that one of them is absolute activity, and the other is relative activity.

My best.
• Nov 24, 2016

Hi Arthur,

In Galilean relativity, which I don't agree with, motion is relative to an arbitrarily chosen frame of reference. Galileo ignored the physical medium which is the cause of inertial phenomena.

Einstein made the situation worse by making the speed of the light fixed in all frames of reference, and so the whole situation became absurd.

I am going back to the drawing board and analysing classical mechanics within the context that there is a luminiferous medium that is the cause of both electromagnetic and inertial phenomena. I call motion relative to this physical medium "absolute motion".

If an oscillating spring is in absolute motion through the luminiferous medium, then we have two modes of activity, both absolute. One is the relative motion between the two oscillating weights on the end of the spring. That represents internal energy. Then we have the absolute kinetic energy due to the motion of the whole contraption through the luminiferous medium.

In a Newton's Cradle, both of these modes of activity are involved, but we don't know the rest frame of the luminiferous medium, and so we don't know the absolute motion of the balls. But still nevertheless, absolute motion gets transferred between balls during the process, but we don't know in which direction. If we knew in which direction the kinetic energy wave travelled along the row, then we would know whether the incoming ball was initially moving, or if the row of nine balls was initially moving, or if both had some initial absolute motion.

Best Regards
David
• The inertial "forces" tha Newton placed in his 4 th to 6th axioms I think are responsible for crushing a body against a rotating cylinder. It is NOT centrifugal force.

Inertial pressures/ wave patterns/ reactions reveal themselves clearly in rotational motions. In terms of the use of the word reaction, inertial pressures/ back emf , back pressure I recognise as reaction to a defined action. But the reactions do not prevent the action they mark a duration of transmission of the pressure into and through a volume.

Much of scientific measurement occurs when a steady state has been achieved. That time or duration is a physical measure of processes of equilibrium establishing themselves within a volume. Much of what we call useful energy or work derives from interrupting this equilibrium process.

To be sure it may take a long time or a long extensive process to establish equilibrium, and a dynamic system in equilibrium may demonstrate extensive and intensive episodic adjustments that only make sense in a larger system. This larger system of equilibrium would be the de facto inertial frame.

Our system of measuring requires a frame of reference. That frame is by definition still. The observable being measured against this still frame.
What Einstein observed was the close similarity between measurements for light speed done using different earth bound frames of reference , and those using earth as an astrological centre to measure other planetary systems.

Thus the speed of light can be measured by observing the moons of Jupiter, and using the observed rotational period tp predict when a moon should appear at the limb. The difference between time of observation and predicted time gives with an accurate estimate of distance between earth and Jupiter a value in the same ball park as on earth.

Now the actual reason why, in my opinion, is because it is a bulk characteristic of the " luminiferous aether" , and therefore independent of any reference frame.

Whether the aether is moving in or through a volume is what makes a difference, thus the Doppler shift for a moving medium should be expected as well as for sources moving in a stationary medium

And the case where we envisage both the medium and the source moving should not be ruled out.

Thus it is unphysical to presuppose that light speed is measurable as the same in every reference frame, but not unphysical to say that the bulk characteristic of an aether is the same in every frame!

That being said, the nature of materiality impinges on expected behaviour of and objects in the aether.

After long consideration I have adopted a pressure surface model of materiality in the aether, where by pressure surface I mean any connected Equipotential 2 dimensional region( a surface) in space.

Such Equipotential
Surfaces may be simple or complex, continuous or discontinuous, convex or concave closed or open .

These are all aspects of trochoidal surfaces, and fully dynamic potentially represent spatial structures and behaviours usually distinguished as particles and fields, in common parlance.
I agree with Einstein and Newton, relativity is the issue and one absolute is necessary to make sense. At the same time no law we frame should be dependent on a particular absolute frame we may pick, and therefore neither should it depend on the scale. This is why quantum mechanics was so abhorrent to Einstein.

• edited December 2016

Nov 8, 2016

Hi Arthur,.

Anyway, right now I'll restrict my reply to the bit about Newton. You are correct that Newton's laws are only a definition. Ernst Mach expressed the matter best by his definition of inertial mass as being the inverse ratio of the acceleration that two bodies exert on each other. That is,

M1/M2 = a2/a1

This equation covers everything to do with Newton's three laws of motion, and you are correct that kinetic energy is a definition that follows on from it.

You are also correct when you say that Kinetic energy has a real effect (when it interacts with another body).

I covered all of this, and the issue of absolute motion v. relative motion, and Galilean relativity in my recent paper about Newton's Cradle,

All The Best

I found this thought provoking.
The paper itself uses absolute in the incorrect sense, or rather non galileannandbthus non Newtonian sense.
Absolute in their time meant, and still means, independent of other interactions, therefore isolateable. That does not make it non relative to a larger system or frame of reference.
In the Dialogo Galileo mentions this property in the mouth of the fool, that in fact certain bodies might move relative to another independently while that other moves relative to another independent body.

This I called the fractal structure of the universe as far as Galileo was oncerned, in that the same rotational pattern occurs at different scales.
For Newton the Absolute space and Time notions were universal relative to God, not any human ?

Secondly the proportion for inertia lacks time dependence.
M/m=at/AT, where we are proportioning the uantity of motion for 2 situations which we are equating by the quantity of motion definition.

To define inertia in this way is a mathematical trick. It says inertia the quantity is a proportion , while inertia, the physical experience is a resistive magnitude that appears in all accelerative situations .

The cradle itself is interesting. If a double layer or triple layer of balls are arranged and the swing balls are aimed/ connected at one row or at different rows what is the outcome?

Is the transfer lineal ?

Just some initial thoughts

How accurate is this simulation ?

Fluid dynamical version
• Nov 16, 2016

Tombes wrote...

OK, so we have now established that kinetic energy transfers between bodies during a collision, and that the transferred velocity increases as the mass of the receiver body decreases.

The discussion now centres on two issues,

(1) Galilean and Einsteinian relativity both deny absolute velocity. They both ignore the issue of whether or not there exists an inertial medium and/or a luminiferous medium, or both all in one. And so long as we analyse linear motion on that limited level of detail, then Galilean relativity appears to be correct.

My argument in the Newton's Cradle article is that if Galilean and Einsteinian relativity are correct, then, due to symmetry, the kinetic energy must transfer instantaneously. That's why I made the error in my 2008 paper "The Aether in Rigid Body Motions".

In my newer Netwon's Cradle article (2014), I have accepted that the kinetic energy transfers at a finite speed and that therefore, by theoretical reasoning relating to time of passage, we can infer the existence of a medium that is the cause of inertial phenomenon. The key realization was that the kinetic energy wave is a separate phenomenon from the deformation wave and that leads to the second issue below

(2) The second issue is that when collisions occur, the physical effects can be segregated into two kinds. (i) A deformation which dissipates as heat, and (ii) a kinetic energy wave, which in my opinion is in the same genre as EM radiation, but differs in density and complexity, as it is based on the atoms and molecules of the material, whereas EM radiation is based on the much smaller molecules of the luminiferous medium. The former does of course through interact with the luminiferous medium.

Take for example a row of weights on a frictionless surface attached together by springs. If we push it at one end, two completely separate things happen. (i) There will be an oscillation wave set up in the system, and (ii) the system as a whole will move linearly and the effect at the far end will seem to be instantaneous, although it is almost certainly not instantaneous.

The kinetic energy wave is not a deformation wave and so it must be a fine-grained rotational wave inside the material, and which interacts centrifugally with the luminiferous medium.

Best Regards

The emboldened words are due to my highlighting what I describe as model inconsistencies that need to be handled carefully in the synthesis of the question

I will have to read Tombes papers to see if he deals with the issue of defining the terms emboldened.
However, both absolute and centrifugal are generally used incorrectly in mechanical discussions if they claim to be Newtonian conceptions. In addition the quantity of motion is usually called momentum, but not understood as Newton intended in mechanical interactions. The so called third law is the law of interactions in which equilibrium and inertia are nascent and after which Newton specifically discusses and attempts to distinguish his recognition of a phenomenon he labels inertia.

• edited December 2016

Some interesting and relevant footage

"The unbending of a bow"

The drop and inertia related to rotating surfaces

• Material and chemical behaviours allied but not identical
Quantity of motion and types of motion are very relevant
• I am personally very disappointed in Tombes 2014 paper on Newtons cradle.
It is not about being right or wrong, but about being imprecise and negligent.
The linear elastic model he proposes is materially outdated and the use of the term absolute , forgivable, is non Newtonian . Forgivable because most scientists do not read the Latin version of the astrological Principles.
The characterisation of Einstins relativistic principle fails to acknowledge that this principle was thoroughly exposited by Newton, after notions by Galileo and says nothing about accrlertive motions as in the case of collisions either elastic or inelastic, but rather about a uniform steady state motion.

Einstins analogicall application of position displacement in a reference frame which subsequently is allowed to move relative to a second frame , both of which necessarily are referenced by the readers fixed frame simply details the measurement scheme the reader must use to calculate displacements in the 2 observed frames. Sometimes the reader may simplify this by coinciding their frame of reference with one of the frames , thus making that designated frame fixed.

Whenever the reader has a fixed reference frame, that frame is absolute. Absolute means independent of any other influence . The Latin means set apart as a sole or single entity. Nothing interferes or affects it. Thus Aristotles prime mover is an absolute reference frame. It moves everything else but itself, and thus nothing else moves it!

Hard material are not generally classed as elastic, but that is because elasticity is a limited concept in material science. The much broader notion is viscosity and this typically derives fom fluid mechanics.

Thus hard materials fall into a highly viscous category with high Reynolds number as a fractal ordering coefficient.

When a hard ball hits a wall high speed photography indeed shows deformations and a lot else besides. That crunching sound is a dead give away as to what happens when hard meets brittle or deforms. Material suddenly beyond its elastic limit.

The notion of a fine grined vorticular substrate transforming, transferring and transducing kinetic energy rotationally is one I personally favour, but it is not general enough for my purposes of modelling magnetic behaviours , and in addition it takes scant account of fractal distribution of regions at this stage. In other words the rotational structure is sufficient but the necessary complexity is deficient in this model.

That the ball drops back from the cradle is evident, as the pendula are slightly separated, and that the whole cradle eventually moves is also evident given sufficient time. The transfer of kinetic energy is usually treated under momentum transfer, which in Newtons proportional model is called quantity of motion. In particular, in Newyons model the centralising accelerative force( either centripetal or centrifugal) is absolute for a specified system, but elemental in a larger absolute system . These elements are simply fractal in Galileos Dialogo model of the known universe centred on the sun.

Further , by design Newton equated motive with quantity of motion so that acceleration of masses within his absolute systems would quantify the accelerative forces of the absolute system. These motives as quantities of motion in the accelerated situation could be balanced against one another by a simple balance lever, and thusly quantified.

Thus the kinetic energy favoured as an invariant by Huygens and others belongs to a different category of dynamics , specifically rotational and pendula dynamics, where the squared velocity relates immediately to Pythagoras theorem
In such a system, rotational transfers are natural but also not necessarily uni directional!

Newyons cradle is too specific a situation to draw any general conclusions in my opinion but of course it is highly interesting for rotational dynamics.