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  • Post #41

Vesselin, I don't blame you for declining debate with relativity deniers. We both know that relativity is controversial nowhere else where science is discussed, and there's no basis for debate.

I've been fascinated by the apparently unlimited capacity in these forums to gin up alternative explanations for known physics in the name of "thinking outside the box," while ignoring that the box is part of the physics, too. Unless one has, like Einstein, built up a complete program of logically closed and experimentally validated judgments, from the earliest ancient knowledge of mechanics and geometry to Minkowski space and Riemannian geometry, I think one is unlikely to get the full import of what "the box" contains.

That said, I know James to be honest in his efforts to deny every mechanical explanation of reality. I don't buy it, and I agree that such denial deprives one of the beautiful experience of comprehending a physically real spacetime.

Best,

Tom

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  • Post #42

Tom and Vesselin,

"...That said, I know James to be honest in his efforts to deny every mechanical explanation of reality. I don't buy it, and I agree that such denial deprives one of the beautiful experience of comprehending a physically real spacetime."

There is no empirical evidence for the existence of space-time. There has never been an experiment or effect observed that involved only space or only time or space and time together. Your belief in the 'real' spacetie is based upon effects observed to occur to objects that are neither space nor time.

The discussion about the reason for not feeling the force of gravity when falling freely has no need for disdain or denial. The fact is that there never was a reason to predict or expect or think that a freely falling person would feel uncrutched or undistorted or undisturbed.

James

Hi Vesselin:

Thanks for your response. Some additional questions below.

Are you saying that the following Einstein's Equivalence Principal of General Relativity is wrong? :

"In the physics of general relativity, the equivalence principle is any of several related concepts dealing with the equivalence of gravitational and inertial mass, and to Albert Einstein's assertion that the gravitational "force" as experienced locally while standing on a massive body (such as the Earth) is actually the same as the pseudo-force experienced by an observer in a non-inertial (accelerated) frame of reference."

Even while standing on earth, the accelerometer reads zero. Does that mean there is no pull force of gravity on any bodies resting on earth? Then why the bodies resting on earth not fly away in all directions away from or tangent to earth? What holds them clinging to earth?

Another question - if there is no force, then what makes a falling body fall - what causes the motion of falling? What determines the direction of fall - why does the body not fall backwards? What determines the amount of acceleration - why is it constant and not some other value than g??

Could you please explain the answers to above to clarify your conclusion that gravity is not a force or gravitational potential energy does not exist?

Please also look into another posted paper - -" Does Gravitational Collapse Lead to Singularities?" that recommends adding the potential energy (implying force) to the energy tensor -

"According to conventional modelling by general relativity the collapse of radially symmetric gravitating objects may end in a singular state. But by inclusion of potential energy into the energy tensor, which is required to guarantee global energy conservation, the occurrence of singularities is avoided. Instead the final states of the collapse of mass concentrations of arbitrary size are nuclear matter objects, from which jets of matter can be recycled into space. The mysterious dark energy, supposed as the main constituent of the universe, may even be the potential energy of matter itself."

I welcome and look forward to your answers and explanations.

Regards and best of Luck

Avtar

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  • Post #44

James,

"There is no empirical evidence for the existence of space-time."

Of course there is. If Minkowski space were not physically real, light would not follow a curved path in the presence of a gravity source, and Einstein lensing would not be observed.

Tom

Tom,

"If Minkowski space were not physically real, light would not follow a curved path in the presence of a gravity source, and Einstein lensing would not be observed."

Yes the would. It would be the theoretical explanation that would change. The evidence remains what it is. The current theoretical explanation is based upon concepts that are empirically unsupported such as deformations of space and time. My message explained that neither space nor time have ever been parts of physics equations including those of relativity theory. The correct explanation will speak about objects and their behaviors. In other words, the correct explanation will be directly tied to actual empirical evidence.

James

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  • Post #46

James,

Spacetime most certainly is described by Minkowski space; that's what Minkowski space *is.* You are correct in some sense that " ... neither space nor time have ever been parts of physics equations ..." in that neither space nor time independently are physically real. Only the Minkowski space model, which supports relativity, preserves space and time, and only by combining them. Spacetime is physically real, both theoretically and demonstrably. "By 'physically real,'" said Einstein, "we mean 'independent in its physical properties, having a physical effect but not itself influenced by physical conditions.'" (The Meaning of Relativity, 1956.)

Tom

Tom and Vesselin,

And by 'physically real', I mean both the effect observed and the cause of it. Neither are naturally theoretical. Neither require nor should involve theoretical speculations. Neither involve space and time as cause nor as intermediaries between cause and effect.

Either empirical evidence is the source of understanding or we become vulnerable to of flights of theoretical fancy. In my essay, I gave the first error of theory and showed that it is also the first error of relativity theory.

Einstein did not explain the nature of the universe to us. He explained his theory. His abduction of space and time into his theory has no empirical justification. The correct explanation will have direct continuous connection to empirical evidence. It won't just fit with the patterns observed in empirical eidence. It will be rooted right from its start in empirical evidence.

It will be expressed in the terms in which the empirical evidence is expressed. Those terms are the units of empirical evidence. The units are those of distance and duration. Everything that follows, in order to remain uncorrupted by theoretical inventions, will continue to be expressed in units of distance and duration no matter how complex the equations become.

James

Hello Avtar,

Let me start by stressing that it is Einstein's "conclusion that gravity is not a force" (not mine) and this conclusion is an established fact in modern physics.

I will answer your questions, but the best way to understand general relativity (GR) and gravitation is to answer those questions yourself by taking seriously the four-dimensional (spacetime) view of the world. Only in the framework of this view one can have genuine understanding of gravitational phenomena; GR showed that only spacetime physical quantities adequately represent the world. Einstein's initial reaction to Minkowski's spacetime physics was negative, but only after Einstein adopted spacetime he was able to arrive at GR.

So your first question is answered - it was Einstein who introduced both the principle of equivalence and the explanation that gravity is not a force, which demonstrates that there is no contradiction between the two (see also the second paragraph in the quote below).

I am sorry that I will have to post again part of what was already posted on this page, but the answers to your 2nd and 3rd question are given there:

"The experimental fact that falling particles do not resist their fall confirmed the geodesic hypothesis in general relativity, which in turn explained why the particles do not resist their fall - the particles' acceleration in the curved spacetime surrounding the Earth is zero, which means that no force is acting on them and they move by inertia. The observed apparent acceleration of falling particles is relative, which is caused by the fact that the particles worldlines and the Earth's worldline converge toward one another (this is called geodesic deviation). Therefore the observed apparent (relative) acceleration of falling particles is caused by the non-Euclidean geometry of spacetime in the Earth's vicinity and is not caused by a force.

When a falling particle hits the ground it is prevented from moving by inertia and it resists its curved-spacetime acceleration (that is why the force of weight is inertial in general relativity in full agreement that there is no gravitational force). The measure of that resistance is the particle's (passive gravitational) mass. So general relativity also nicely explains why inertial and passive gravitational masses are equal."

I think the following analogy, often given to illustrate the essence of GR (that no gravitational force in involved in gravitational phenomena), is most helpful. Imagine that a distance separates two observers whose locations are exactly on the equator. They decide to move north by following a path that is perpendicular to the equator. As they move and monitor the distance between them they discover that they are approaching each other. If they are unaware that the Earth surface is spherical they would think that they move on a flat surface and the only explanation of their getting closer would be that they are subject to some force. The truth is that no force is acting on them; simply they move on the surface of a sphere.

So the fact that the observers approach each other can be explained by two hypotheses - (i) either they live in a flat world and there is a force between them, or (ii) no force is causing their mutual attraction since they live on a curved surface (this analogy is best understood in terms of spacetime when you consider the worldlines of the observers which converge towards each other exactly like the meridians converge towards the North Pole). A crucial piece of evidence can help the observers determine which hypothesis is the correct one - the acceleration between the observers while they are approaching each other is exactly the same no matter what the masses of the observers are (by contrast, a given real force accelerates different masses differently). Falling bodies of different masses fall with the same acceleration.

I hope this helps. Best wishes.

Hi Vesselin:

Thanks for the clear explanation.

Why do you think general relativity is unable to explain dark energy and dark matter and suffer with the Black Hole singularity? What is missing? How it can be fixed?

Thanks

Avtar

Hello Avtar,

These are several (at least two) different issues whose resolutions have nothing to do with what is confirmed by experiment in GR. As you know a lot of approaches have been offered to deal with what is called dark matter and energy, but practically we know close to nothing certain about them.

Regarding singularities (and this might apply to the above issue), we can have a better idea of them only when we direct our attention to what I think is the real open question in GR - how matter curves spacetime.

I would like to stress one crucial point - our accepted theories are not universally valid; they have a domain of applicability / validity. They will never be disproved in their domains of validity (because their predictions have been repeatedly confirmed by experiment and one can't disprove experiments).

A physical theory breaks down beyond the domain of its validity. It might turn out that this is the case with GR when applied beyond its domain to deal with singularities (since it is now assumed that the singularities might lie in the domain of quantum physics). We have a good example of such a case - special relativity breaks down (is not fully valid / applicable) at the quantum level since its equations of motion manifestly fail to describe the behaviour of quantum objects. However, that does not mean that special relativity is wrong; it is perfectly valid in its domain.

The not fully studied issue of validity of physical theories is very important and interesting, but it is not the subject of my essay (and of the contest) and I do not like to participate in any discussion on it.

All the best.

Hi Vesselin:

Thanks for your response. Please excuse me for some additional questions (I am trying to learn and clarify GR concepts) on your paper and I would greatly appreciate your answers in the light of general relativity:

Q1: If gravity is not a force, why and how an apple detaches from the tree and accelerates its falling motion towards earth from the initial state of zero velocity. Does it not require a force of gravity to break the bond between the apple and tree? If there is no force of gravity, should the apple not stay put on the tree without breaking away from it?

Q2: Why the upward lifting force of a rocket is required to lift a space shuttle or satellite of the launch base and into the orbit? Is it not true that the lifting force of the rocket is required to overcome the force of gravity?

Thank you for your kind patience and responsiveness,

Regards and best of Luck

Avtar

Hello Avtar,

The answers of both questions are contained in what I wrote earlier (replying to one of your posts):

"When a falling particle hits the ground it is prevented from moving by inertia and it resists its curved-spacetime acceleration (that is why the force of weight is inertial in general relativity in full agreement that there is no gravitational force)."

In more detail: GR showed that only 4D quantities adequately represent physical phenomena. The 4D curved-spacetime acceleration (CSA) (representing the curvature or rather the deformation of a geodesic worldline which represents a free particle moving by inertia) of a falling particle is zero. So, like in Newtonian physics, zero acceleration => zero force; therefore a falling particle is not subject to any gravitational force in full agreement with the experimental fact that a falling particle does not resist its fall (which proves that no force is causing its fall). The falling particle moves by inertia (its 4D CSA = 0) and its worldline is geodesic (which is analog of a strait worldline in curved spacetime).

When the particle reaches the ground... see the quote above. The worldline of a particle at rest on the ground is not geodesic, i.e. the worldline is deformed which gives rise to a static resistance / restoring force in the particle's worldline or rather worldtube (like the resistance / restoring force arising in a deformed rod). That restoring force is inertial (see the quote above) and has been traditionally called gravitational force or the weight of the particle. So the apple breaks the bond because of the force of its weight; or more correctly (in terms of GR) - the bond has been preventing the apple to move by inertia (i.e. to fall) and the inertial force arising in the apple breaks the bond; or even more correctly (in terms of spacetime) - the bond has been deforming the apple's geodesic worldtube (deformation => 4D CSA => 4D force) and the static restoring force in the deformed worldtube of the apple (the inertial force) breaks the bond.

Your second question - the rocket deforms the worldtube more than the ground by making the rocket move upwards and the restoring force is even greater and has to be overcome.

Genuine understanding of the world, not just SR and GR, is only possible when spacetime and worldlines (worldtubes) are taken seriously; they are the ultimate reality; the 3D object we observe in everyday life are only 3D images / light reflections from the worldtubes of physical objects. To see that this is really the case, assume that those worldlines (and spacetime) are nothing more than geometrical abstractions and rigorously analyze Minkowski's explanation of length contraction shown in Fig. 1 of his famous paper "Space and Time" (it is contained in the free version of a book H. Minkowski, Space and Time: Minkowski's papers on relativity; the pdf file is available at: http://minkowskiinstitute.org/mip/books/minkowski.html). You will see that length contraction is impossible in a 3D world. The same is also true for the other kinematical relativistic effects.

Good luck.

P.S. Much more detailed explanations of everything we discussed here are given in a book "Inertia and Gravitation" which I am now completing; it will appear by the end of September.

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  • Post #53

" ... by 'physically real', I mean both the effect observed and the cause of it."

Then you've condemned yourself to an irrational explanation of the physical world, James. Simultaneous observation of cause and effect is impossible in principle. Were it not so, rational correspondence of language to meaning (theory to result) would be superfluous, because mere observation would replace language -- in which case, how would one communicate the results of the observed phenomenon except by telepathy?

Tom

"one can't disprove experiments"?

See references 20 to 30 of my essay, in particular Nimtz who measured superluminal propagation of light.

Eckard Blumschein

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  • Post #55

Hi Vesselin. Instanteaneity quantizes gravity insofar as gravity cannot be shielded and there is balanced attraction and repulsion in conjunction with balanced and equivalent inertia and gravity.

Real/fundamental quantum gravity requires fundamentally balanced and equivalent gravity and inertia AND attraction and repulsion as well. This fundamentally stabilizes and balances distance in/of space.

Hi Vesselin,

I finally found and read your essay. I was sort of expecting some contradicting ideas in your essay compared to mine, but I didn't find any and if yours had been written before mine and I had seen it, I would have used it as a reference. You drive at points that my essay says so in two sentences. Clearly faltering on my part on those points. Anyway, I thank you for your essay if only to clear up in my mind that I am not the only one thinking these crazy thoughts.

Jim Akerlund

Hi Vesselin:

Thanks for your GR based interpretations of gravitation. I really appreciate your clear expression and patient response.

Let me reiterate that I am in complete agreement with the two fundamental conclusions in your paper.

1. Quantum Gravity theory cannot be developed because gravity cannot be quantized.

2. Gravitational waves do not exist.

However, GR simply translates gravitation force to a different coordinate system of world-lines and geodesics, hence deferring a gravity force to a static force in the deformed world-tube. Just like, a sphere loses its normally understood definition of a sphere when strictly described in Cartesian (x, y, and Z) coordinates instead of simple spherical coordinate system, gravitational force loses its meaning in GR coordinates. The fact remains that a force is required and exerted on the apple to break its bond that represents a potential energy, whether the force comes from a static force of a deformed world-tube or a simple gravitational force (well measured and documented in many many experiments) is only a matter of whether a GR or Newtonian coordinate system or description is used.

Secondly, GR has its own serious fundamental weaknesses at quantum scales due to its inherent singularities resulting from an infinite mass being confined to an infinitesimal volume. Because of these singularities, GR cannot be fundamentally used to counter quantum gravity arguments. One cannot use a broken theory - GR to counter a hypothetical theory - QM at quantum scales. It's like a blind trying to lead a lame. While GR is a highly successful theory for applying to those phenomena wherein the relativistic effects are important, it is highly inefficient, in spite of its majestic appearance, to apply to the classical worldly gravitational phenomena wherein relativistic effects are insignificant.

In order to use relativistic arguments to counter the incomplete and inconsistent QM theory including the hypothized quantum gravity, one must first cure the singularities of general relativity theory at quantum scale. This is the objective of the GNMUE model developed and described in my paper --" From Absurd to Elegant Universe" that integrates the missing physics of spontaneous decay into a simplified form of general relativity that includes specific relativity and gravitational potential. The results of the model show that the relativistic gravitational effects at quantum scale can be successfully predicted without any singularities experienced by GR. This also eliminates the need or relevance of the so far unsuccessful efforts of unifying the gravity and other fundamental forces of the standard model. The model also resolves many other paradoxes and inconsistencies of modern physics and explains relativistic understanding of the inner workings of QM.

I would greatly welcome your thoughts on the above.

Thank you again for your kind patience and responsiveness,

Regards and best of Luck

Avtar

Vesselin

"Speed of light only c in local inertial frame" (in GR). I certainly agree, and have shown how it is also possible in SR. I think I agree with much else but must now re-read your well written piece more slowly and absorb more.

I'm writing 3 papers including re-analysis and interpretation of Hermann Minkowski's work with John Minkowski and including Jan Minkowski's quantum optics work. A very consistent ontological construction has emerged overcoming some paradoxical matters and seemingly quite consistent with much of your work. I must look into the Minkowski Institute.

I hope you will be able to read my essay and grasp the complex conceptual dynamics densely packed beneath some metaphysical theatre. I hope you may find important consistencies and derivations, but mine too must be read slowly.

Best of luck in the competition. I hope you do very well.

Peter

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    • Post #59

    Dear Mr. Petkov,

    I began reading your essay today and I find your point is well put and depends primarily on the fact that falling bodies offer no resistance to their "apparent" accelerations. I am not aware of such a fact so I must ask you to route me to it, please. If you have it in your essay by reference to something else, would you plese let me know where? Thank you.

    Hi Vesselin:

    You may have missed my reply post above, hence I am reposting here.

    Thanks for your GR based interpretations of gravitation. I really appreciate your clear expression and patient response.

    Let me reiterate that I am in complete agreement with the two fundamental conclusions in your paper.

    1. Quantum Gravity theory cannot be developed because gravity cannot be quantized.

    2. Gravitational waves do not exist.

    However, GR simply translates gravitation force to a different coordinate system of world-lines and geodesics, hence deferring a gravity force to a static force in the deformed world-tube. Just like, a sphere loses its normally understood definition of a sphere when strictly described in Cartesian (x, y, and Z) coordinates instead of simple spherical coordinate system, gravitational force loses its meaning in GR coordinates. The fact remains that a force is required and exerted on the apple to break its bond that represents a potential energy, whether the force comes from a static force of a deformed world-tube or a simple gravitational force (well measured and documented in many many experiments) is only a matter of whether a GR or Newtonian coordinate system or description is used.

    Secondly, GR has its own serious fundamental weaknesses at quantum scales due to its inherent singularities resulting from an infinite mass being confined to an infinitesimal volume. Because of these singularities, GR cannot be fundamentally used to counter quantum gravity arguments. One cannot use a broken theory - GR to counter a hypothetical theory - QM at quantum scales. It's like a blind trying to lead a lame. While GR is a highly successful theory for applying to those phenomena wherein the relativistic effects are important, it is highly inefficient, in spite of its majestic appearance, to apply to the classical worldly gravitational phenomena wherein relativistic effects are insignificant.

    In order to use relativistic arguments to counter the incomplete and inconsistent QM theory including the hypothized quantum gravity, one must first cure the singularities of general relativity theory at quantum scale. This is the objective of the GNMUE model developed and described in my paper --" From Absurd to Elegant Universe" that integrates the missing physics of spontaneous decay into a simplified form of general relativity that includes specific relativity and gravitational potential. The results of the model show that the relativistic gravitational effects at quantum scale can be successfully predicted without any singularities experienced by GR. This also eliminates the need or relevance of the so far unsuccessful efforts of unifying the gravity and other fundamental forces of the standard model. The model also resolves many other paradoxes and inconsistencies of modern physics and explains relativistic understanding of the inner workings of QM.

    I would greatly welcome your thoughts on the above.

    Thank you again for your kind patience and responsiveness,

    Regards and best of Luck

    Avtar