Paradoxes and Dilemmas

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21 years 10 months ago #3956 by Jim
Replied by Jim on topic Reply from
Can the data sited by TVF about the solar constant or the daily change of distance to the sun be accessed? I am very interested in any data that can aid in clearing my confusion about the posted result.

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21 years 10 months ago #3990 by Samizdat
(quoting tvanflandern)

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[N. DeRosa]: Some scientific theories can't be understood no matter how carefully we read them. Einstein's theory of Special Relativity is one such theory.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

I used to think that too, but now understand that SR involves no logical contradictions. It does violate common sense, and is almost certainly wrong. But there is a way to understand it that is at least possible.

<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Is it just me, or are we slipping into metaphysics here? Why would anyone want to try to understand something that is "almost certainly wrong?" How do you define "wrong?" Where exactly is the theory wrong? What experiments can you cite which disprove SR? Show me a centrifuge large enough on which to mount a small clock, I'll show you SR in practice. How do you define away data which support SR?

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21 years 10 months ago #4546 by Samizdat
(quoting atko)

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Speed, or velocity only makes the clock appear to go slower (according to GR). <hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

You are confusing SR and GR. How can we possibly hope to have meaningful discussion when such glaring misconstruings go unchecked?

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21 years 10 months ago #3991 by tvanflandern
<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[makis]: If a body is on a uniform circular motion, the only acceleration acting on it is the centripetal, equal to v^2/r. There is no other acceleration, because angular momentum is conserved.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Agreed.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>B. If a body moves on a circular path and has an angular acceleration, in addition to the centripetal (same v^2/r) it has an acceleration tangent to the path equal to: r x omega dot. This means that the angular speed will keep increasing. Obviously, that's not the case with the Earth, that is, circular motion is uniform. Therefore, the only acceleration on Earth is the centripetal, which causes its transverse path due to constant linear v to become circular. This is according to Newton the pulling action by the Sun.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Agreed. (Actually, a forward angular acceleration produces a <i>slower</i> angular speed because it increases the mean distance from the Sun. But that is a minor detail for this discussion.)

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>What remains to be investigated is the pulling action of the Earth on the Sun. That is the so called centrifugal force on the Sun (Actio-Reactio). Given a uniform circular orbit and a stationary Sun, as it was analyzed by Newton, the result will be an acceleration of the Sun towards the Earth, as there is nothing to stop the Sun from moving.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

I do not understand the basis for these claims. Earth's pull on the Sun is <i>not</i> a centrifugal force, but a centripetal one. It is <i>not</i> a reaction force, but an independent force that could be zero (if Earth's mass were zero) or equal to the Sun's (if Earth's mass equaled the Sun's) or anything in between.

As for Newton's analysis, that is irrelevant to today's understanding. Newton started with the assumption that the Sun stood still, but ended with the realization that it must also move. Today, we do not use a fixed Sun except in certain very simplified approximations of reality. The planet masses are not small enough to neglect their forces on the Sun. In today's two-body problem, both bodies move. [Note that we are free to put the origin of the coordinate system anywhere convenient, and often put it at the Sun. This choice does <i>not</i> imply that the origin is non-moving! We make that choice simply because the Sun is observable and the barycenter is not.]

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Given an elliptical orbit, angular acceleration will result.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

This is not true. Earth's pull on the Sun is along the same Sun-Earth radial as the Sun's pull on Earth. The resulting net force between the Sun and the Earth will be identical to that for the case where the Sun's mass is replaced by (Sun+Earth) and Earth's mass is zero. It is also identical to the case where both bodies have mass (Sun+Earth)/2. So the resulting relative motion between the two bodies is identical in all these cases because the net force is identical.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I maintain that explanations given up to this point were more complicating the issue than clarifying it.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

If you don't like the explanations in one book, try another. Different authors explain the matter differently. I mentioned my own preferred text by Danby. Not understanding one author, or seeing that he is mistaken, is not a good basis for generalizing that the whole field is wrong.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I have not seen any solution of the two-body problem which considers the center of the Sun NOT stationary. Most proofs resort to a "cheating" using the barycenter.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

How is it possible for the Sun to remain stationary when it is in the gravitational field of the Earth? Earth's gravity is non-zero. Your words fail to make sense to me.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>It is exactly the existence of a barycenter that we must prove in the first place, if we are to make sure that the earth and the sun remain at constant distance. By assuming a barycenter already exist and making a Galilean transformation (another cheating) we actually making an assumption that our law (inverse square) works well and all is left is to find the path of the earth! This type of magic mathematics and use of inverse logic has confused even serious scientists.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

We do not assume a barycenter exists. We derive that result from Newton's laws. In <i>Dark Matter, …</i>, I explained why nature requires that forces be inverse square. (E.g., graviton shadows become less dense as their cross-sectional area increases away from the source, and that area is proportional to the square of distance in any flat space.)

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I challenge you TVF to model the sun-earth system according to my approach and write the equations of motion. You have a Ph.D. in orbital mechanics and the knowledge necessary for doing that. I am just a struggling common sense mind that does not get bought into anything that is "sold" to be public for free. If you are ever able to solve the equations then you will realize that things are much more complicated than they appear to be. (First, trying to find a convenient inertial reference frame to get generalized coordinates is a problem. That is why, implicitly, one planet is fixed, which is a joke.)<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

As you yourself remarked, radial forces are required to conserve angular momentum. Your model involves angular accelerations, thereby guaranteeing instability.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I have followed your (TVF's) chain of thought in the Pushing Gravity book and I am convinced you realize all the above problems but you want me to "lay off" in a polite way, in a sense, since you, or anybody has the answers. It is worthwhile, however, to admit to the problems and put things under a different perspective.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Every student of celestial mechanics does these things as an exercise, trying out many different force laws and observing the effects on bodies. We also derive from scratch all the current laws in use. If you detect a twinge of impatience in my responses, it is because I do not yet see in your challenge anything original, but only matters already solved in the textbooks. I ask again where the burden should fal

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21 years 10 months ago #3958 by tvanflandern
<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>[Jim]: About the solar constant being different than the modified constant posted by NASA- Why is the solar constant posted in a form that is totally faked by corrections that are made so it conforms to the designed orbit of Earth? This is how I see the process you seem to feel is quite OK.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

If we care about the apparent brightness of the Sun or a star, we list its apparent magnitude, which is affected by its distance.

If we are interested in the absolute (real, intrinsic) brightness of any light source, we factor out the effect of its actual distance, and give the brightness at some standard distance. That way, we can compare the real brightness of stars; e.g., which stars give off more or less light than the Sun.

If we gave the Sun's observed, apparent brightness, that is not constant, so it is not useful to make comparisons with other measures, even of the same object, because the distance is variable. By taking out the distance variation, we can study if the Sun's real brightness varies or is constant.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>The real constant must not be constant at the true distance of Earth so why not post this data as well as the posting in service now?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

The raw data remains available. It just isn’t of much use to most people for the reason stated. Who cares about the variation with distance?

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Can the data cited by TVF about the solar constant or the daily change of distance to the sun be accessed?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

It may be available on the Internet. Try a search engine. But if not, all astronomical data is supposed to be archived in the National Space Sciences Data Center. -|Tom|-


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21 years 10 months ago #3959 by tvanflandern
<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Is it just me, or are we slipping into metaphysics here? Why would anyone want to try to understand something that is "almost certainly wrong?"<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

I consider deduction, observations and experiments to be physics, not metaphysics.

Special relativity (SR) has been the dominant paradigm for the relativity of motion for the better part of a centruy now; so it remains relevant if the theory has just been falsified by recent observations, or if it was always internally inconsistent (as many still maintain). I was arguing for the former case over the latter.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>How do you define "wrong?"<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

I define "wrong" as either internally inconsistent or falsified by observations or experiments.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Where exactly is the theory wrong? What experiments can you cite which disprove SR?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

It is wrong (i.e., inconsistent with observations and experiments) in predicting that real entities cannot travel faster than light in forward time. We now have six experiments that say otherwise. See my paper “The speed of gravity – What the experiments say”, Phys.Lett.A, v. 250, #1-3, pp. 1-11 (1998/12/21); also available at the "Cosmology" tab, "Gravity" sub-tab of this web site.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Show me a centrifuge large enough on which to mount a small clock, I'll show you SR in practice. How do you define away data which support SR?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Why such a crude experiment? The GPS now tests the predictions of SR and GR to better than a part in 1000.

There are now eleven independent experiments that test various aspects of SR and confirm them. Nobody "defines away" this data. Neither does any of this prove SR is "right" (a task that is impossible in physics). In fact, none of the eleven experiments distinguish SR from Lorentzian relativity (LR), at least not in favor of SR. (Four experimenters -- DeSitter, Sagnac, Michelson, and Ives -- claimed at the time their results came in that they falsified SR in favor of LR. But the predictions of SR were "reinterpreted" to keep them consistent with the experiments.)

Despite eleven experiments "confirming" SR, none of the eleven test the reciprocity of the effects between two frames. SR and LR differ in that the former has no preferred frame and the latter has one -- the local gravity field. It turns out that reciprocity is crucial to SR's prediction that FTL motion in forward time is impossible for real matter. Because that prediction is now falsified, we can be sure that SR is falsified, as concluded in “Experimental Repeal of the Speed Limit for Gravitational, Electrodynamic, and Quantum Field Interactions”, T. Van Flandern and J.P. Vigier, Found.Phys. 32(#7), 1031-1068 (2002).

I gather your technical journal reading is at least four months behind. <img src=icon_smile.gif border=0 align=middle> -|Tom|-


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