Relativity

The Special Relativity Definition Problem

This topic contains 0 replies, has 1 voice, and was last updated by Profile photo of Bruce Nappi Bruce Nappi 5 months, 3 weeks ago.

  • Creator
    Topic
  • #388
    Profile photo of Bruce Nappi
    Bruce Nappi
    Participant

    The confusion over what precisely defines “Special Relativity” (SR) has been going on in CNPS, without resolution, for a very long time. I pulled together this overview hoping to move this problem forward.

    The differences appear to rest on the following basic issues:

    1. The members can not agree on a single interpretation for the term “Special Relativity” (SR). Some say it applies, specifically, to Einstein’s 1905 paper. Others claim SR includes clarifications and expansions of the 1905 paper provided later by others.
    2. When SR supporters are asked to provide a specific list of references that clarify and expand the 1905 paper, very often, none are provided.
    3. When either Einstein’s or later works are challenged on a mathematical and physics bases, SR supporters frequently can not identify the sources of specific equations or physics principles they are referring to (with some exceptions for Minkowsky diagrams). Instead, only “generalized” statements are given that all relativity concepts must be included.

    In order to help resolve this confusion, I will provide excerpts taken directly from the 1905 paper (1). I am also providing two excerpts from an article (2) written by Einstein himself, for the London Times in 1919. Below are the excerpts from the 1919 article in original form. I have added { } brackets with numbers for paragraph references. I’m assuming that members have access to the 1905 paper. For readers that don’t, a citation is provided at the bottom of this post.

    {1.} “After the lamentable breakdown of the old active intercourse between men of learning, I welcome this opportunity of expressing my feelings of joy and gratitude toward the astronomers and physicists of England.”
    {2.} “…the theory of relativity resembles a building consisting of two separate stories, the special theory and the general theory. The special theory, on which the general theory rests, applies to all physical phenomena with the exception of gravitation; the general theory provides the law of gravitation and its relations to the other forces of nature.

    It has of course been known since the days of the ancient Greeks that in order to describe the movement of a body, a second body is needed to which the movement of the first is referred. The movement of a vehicle is considered in reference to the earth’s surface; that of a planet to the totality of the visible fixed stars. In physics the body to which events are spatially referred is called the coordinate system. The laws of the mechanics of Galileo and Newton, for instance, can only be formulated with the aid of a coordinate system.

    The state of motion of the coordinate system may not, however, be arbitrarily chosen, if the laws of mechanics are to be valid (it must be free from rotation and acceleration). A coordinate system which is admitted in mechanics is called an “inertial system.” The state of motion of an inertial system is according to mechanics not one that is determined uniquely by nature. On the contrary, the following definition holds good: a coordinate system that is moved uniformly and in a straight line relative to an inertial system is likewise an inertial system. By the “special principle of relativity” is meant the generalization of this definition to include any natural event whatever: thus, every universal law of nature which is valid in relation to a coordinate system C, must also be valid, as it stands, in relation to a coordinate system C’, which is in uniform translatory motion relatively to C.

    The second principle, on which the special theory of relativity rests, is the “principle of the constant velocity of light in vacuo.” This principle asserts that light in vacuo always has a definite velocity of propagation (independent of the state of motion of the observer or of the source of the light). The confidence which physicists place in this principle springs from the successes achieved by the electrodynamics of Maxwell and Lorentz.

    Both the above-mentioned principles are powerfully supported by experience, but appear not to be logically reconcilable. The special theory of relativity finally succeeded in reconciling them logically by a modification of kinematics – i.e., of the doctrine of the laws relating to space and time (from the point of view of physics). It became clear that to speak of the simultaneity of two events had no meaning except in relation to a given coordinate system, and that the shape of measuring devices and the speed at which clocks move depend on their state of motion with respect to the coordinate system.”

    Discussion
    1. The first excerpt {1}, “After the lamentable breakdown of the old active intercourse between men of learning..” shows that, already in 1919, scientists had lost the ability to discuss scientific principles with logic and respect. As I said in my initial observations, the current discussions have still not solved this. Until a new approach is found, the results will continue to cause confusion (which is why I started the MAP effort.)

    2. When describing “the theory of relativity” in his 1919 article, many follow-on studies and writings related to his 1905 work had already been done. These included studies by Kaufmann, Planck, Bucherer, Laub, Laue, Minkowsky, and others. Yet, Einstein still associates SR only with his own concepts. That is, he did NOT consider the “theory of relativity” to be a collection of clarifications and expansions on HIS own work. His failing to reference any of them in the 1919 article is a clear rejection, by omission, that any of them had clarified or expanded on his ideas, thereby supporting his ideas.

    To help improve our discussions going forward, I’d like to suggest that discussions of SR now use two separate descriptors: E-SR (1905 Einstein relativity) and SM-SR (Standard Model Special Relativity. The second being composed of all writings including, clarifying and expanding on E-SR. If a discussion refers to SM-SR relativity, it should specify what document is implied. As the history shows, the concepts presented by the “relativity” scientists listed above have all been both extensively quoted, but also contested.

    3. Einstein clarifies the scope of SR: “The special theory, on which the general theory rests, applies to all physical phenomena with the exception of gravitation…”

    4. E-SR includes the following assertions from the paper’s first page: [Experiments] “suggest that the phenomena of electrodynamics as well as of mechanics possess {A} no properties corresponding to the idea of absolute rest. They suggest rather that…, {B} the same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good. We will raise this conjecture (the purport of which will hereafter be called the Principle of Relativity”) to the status of a postulate.

    I highlighted multiple words that I think need to be clarified and stressed.

    a. The word “suggest” is used repeatedly. This is a formal scientific style commonly used to show respect for the scientific method and the implied integrity of other researches. In this case, Einstein intentionally used that term to stress he was setting out a hypothesis for the paper, not making a claim.

    b. A “conjecture” is: a conclusion formed on the basis of incomplete information. So, Einstein, himself, acknowledged that he had insufficient empirical data to raise electrodynamic theory and empirical evidence to the level of “settled theory”. Instead, he was summarizing an analysis, based on postulates that he believed would have to be true if the conjecture was true, to see what conclusions would be reached.

    c. A postulate is: an assumption of the truth of something, without proof, only as a basis for reasoning.

    d. A purport is: a meaning or summarization.

    5. Therefore, it was Einstein, himself who labeled the combined concepts {A} and {B} the “Principle of Relativity”. That was done in E-SR. He reaffirms this, and further associates E-SR with the term “Special Relativity” in his 1919 article as noted above in point 3.

    6. The negative interchange in the online discussions has been encouraged by the fact that the word “Special”, in relation to Relativity, was not directly specified in the 1905 paper. It actually did not emerge until years after the 1905 paper. Other documents of the time note that the term “Special Relativity” was already recognized in the scientific community prior to its appearance in the London Times in 1919. But that means, in Einstein’s view, any physics adequate to merit inclusion by him as integral to the “term” SR, as used in the 1919 article, had to be done between 1905 and 1919. The 1919 article, written by Einstein himself, clearly rejects these contributions by his lack of mentioning or crediting any of them. This conclusion is further supported by the following statement in the article, “Both the above-mentioned principles are powerfully supported by experience, but appear not to be logically reconcilable. The special theory of relativity finally succeeded in reconciling them logically by a modification of kinematics.” The phrases, “powerfully supported by experience, but appear not to be logically reconcilable” and “special theory of relativity finally succeeded”, were his rejection of any contributions from the work of others to enable his theory.

    7. It is understandable that this confusion continues to exist in this discussion and in CNPS. It is ubiquitous throughout modern society in both scientific and lay communities. For example, the Wikipedia article “Special Relativity” states, “In physics, special relativity SR, also known as the special theory of relativity or STR, is the generally accepted and experimentally well-confirmed physical theory regarding the relationship between space and time.” Another Wikipedia article, however, “History of Special Relativity”, uses different wording: “On September 26, 1905, Albert Einstein published his annus mirabilis paper on what is NOW called special relativity.”

    These two phraseologies were both refuted by Einstein in his 1919 article. The Wiki “Special Relativity” article claims SR is the “generally accepted” theory of space and time. Einstein did not support that, clearly stating that SR meant his 1905 paper – the implication being it was not a generally accepted conglomeration of views. The “History of Special Relativity” article states E-SR is what is now called special relativity, supporting the previous sentence.

    8. Why does this confusion continue? Because the issue is socially a deep emotionally driven issue. Human’s have a strong drive for “ownership” of words and phrases they believe to be socially valuable. The higher the perceived value, the higher the related emotions. When initially established definitions for words and terms do not conform to personal beliefs, people frequently change their operative definitions so they do conform. This is done independent of the history of the definitions, typically introducing contradictory concepts. Social conflict arises when the change of definition is challenged. While any such challenge can be efficiently resolved by reference to historical documents, for both language and scientific clarification, the same emotions that lead a person to deny the original definition to begin with, drive a continuing denial that does not want to resolve the conflict. While these kinds of conflicts are usually presented as mathematical or physics disputes, they are predominantly psychologically driven.

    9. Many society members strongly dispute that E-SR or SM-SR has been experimentally “well-confirmed”. But it has been hard to get members to do the homework on this needed to gather a sound bibliography that summarizes what those experiments are. I will propose some projects to move this along as well.

    (1) On the Electrodynamics of Moving Bodies, A. Einstein, June 30, 1905 (Fourmilab version) http://www.fourmilab.ch/etexts/einstein/specrel/www/

    (2) “What Is The Theory Of Relativity?” Albert Einstein, November 28, 1919, Letter to the London Times, taken from German History in Documents and Images, Volume 6. Weimar Germany, 1918/19–1933 http://germanhistorydocs.ghi-dc.org/pdf/eng/EDU_Einstein_ENGLISH.pdf .

You must be logged in to reply to this topic.

Skip to toolbar