Circular letter - Translated by Easy Translate
And what if Einstein was wrong on a crucial point
in his analysis leading to the special relativity?
on February 14th, 2018
In order to try to answer as clearly as possible
the question of
Mr Richard Taillet
First recipients of the letter : Ms Sophie Roux, Mr Richard Taillet, Mr Étienne Klein, Mr Marc Lachièze-Rey, Mr Élie During, Mr Alain Connes, Mr Basarab Nicolescu, Mr Carlo Rovelli, Mr Robert Signore.
Richard Taillet wrote, on October 21st, 2017 at 3:43 pm
« Heu… Juste pour comprendre votre démarche : vous êtes en train d’envoyer un message à 14 personnes dont vous estimez qu’elles sont expertes en relativité, à un titre ou un autre, pour leur expliquer la notion de relativité de la simultanéité ? C’est ça ? Si oui, qu’est-ce qui vous fait penser que ces personnes n’ont pas déjà les idées au moins aussi claires que vous sur le sujet ? (ce n’est pas pour vous envoyer dans les cordes, c’est une vraie question dont la réponse m’intéresse). »
“Hello... Just to understand your approach: you are sending a message to 14 people that you think they are experts in relativity, in one way or another, in order to explain the concept of relativity of simultaneity? That's right? If so, why do you think that these people do not have already the ideas at least as clear as you on the subject? (It's not to see you on the ropes, but it's a real question whose answer is interesting to me)."
I will first answer a little that question point blank, and then, in the following three sections, will explain my argument before concluding.
If physics had really dealt with this question, it would be already shown, for more than 100 years, that there is necessarily an absolute simultaneity at the physical level, but not a relativity of simultaneity. This would completely change his conception of space-time and movement. I admire, for example, the subtleties analysis of Étienne Klein, by listening with interest to his various lectures, but it will be necessary one day or another that he examines this subject deeply. It is a necessary milestone, with a deepening of the notion of causality, for a specialist in the question of time. But, even if he admitted the thesis of my book “And if Einstein was wrong on a crucial point in his analysis leading to the special relativity?” - Et si Einstein s’était trompé sur un point capital dans son analyse aboutissant à la relativité restreinte? ” he received a few months ago, having the competences in philosophy and physics to understand the ins and outs; it is difficult for him to take a position. Indeed, it is not so easy to face the ruling a priori and to expose this issue succinctly. It could also be an opportunity for a book, co-written by scientists and philosophers, in order to deal better with this issue than just my own achieved effort. I think that only if this problem would be completely solved, then physics would be able to reach a general theory of the Universe.
A) Einstein called into question the idea of absolute simultaneity by evoking the relativity of simultaneity, and scientists are thinking now that we can no longer speak of neither absolute simultaneity nor relativity of simultaneity.
In a conference (1) Marc Lachieze-Rey pointed out that Einstein notes, firstly, that the notion of simultaneity cannot exist. Among the evoked reasons would be that it is impossible for distant observers to agree on what is simultaneous and on what is not.
« L’impossibilité de se mettre d’accord sur une réponse (…) nous indique non seulement que la simultanéité n’existe pas, mais aussi que la notion de temps ne peut pas exister. »
"The impossibility to agree on an answer (...) indicates us not only that simultaneity does not exist, but also that the notion of time can not exist."
Indeed, it is not because - from an operational point of view - that we can not know if two distant events are simultaneous, that it means that the simultaneity between them can not exist. To have a speed, is to move from one point to another for some time, and in order that a ray of light could travel a distance with respect to such an observer, then the ray of light must be at such a time at such a distance from him. When the light ray was at such a distance, the clock of the observer marked such a time. There is simultaneity between the two events, even if it is difficult to know it, at the reception of the light ray, in accurate manner (2). These things being admitted, we realizes that, within the context of an absolute simultaneity, the speed of light can no longer be invariant, even if when varying the approach of durations and distances (3). That’s why; the invariance of the speed of light implies the relativity of simultaneity at the physical level. The latter is implied thought the experiment of Einstein train, even if it is not stated explicitly, the said experiment was only studying the consequences of the supposed invariance of the speed of light with respect to any inertial frames of reference (4).
« Des événements qui sont simultanés par rapport à la voie ferrée ne sont pas simultanés par rapport au train et inversement (relativité de la simultanéité). Chaque corps de référence (système de coordonnées) a son temps propre ; une indication de temps n’a de sens que si l’on indique le corps de référence auquel elle se rapporte. » Einstein, A., La théorie de la relativité restreinte et générale, pages 28-29, Gauthier-Villars.
"Events that are simultaneous relatively to the railway are not simultaneous with the train and inversely (relativity of simultaneity). Each reference frame (coordinate system) has its own time; an indication of time makes sense only if the reference frame to which it relates is indicated.
Einstein, a., La théorie de la relativité restreinte et générale (the book in french: The special and general relativity theory), pages 28-29, Gauthier-Villars.
This implies that the principle of relativity of simultaneity at the physical level should be formulated as follows: when the two observers are at the same distance from the two light sources - that is to say when they are facing each other - the light ray at the rear of the train is supposed to exist to the observer of the station and not to that of the train (5). The physics has not necessarily explicitly expressed things in this way, because this implies rather a philosophical reasoning. There is no possible invariance of the speed of light without the relativity of simultaneity at the physical level, even over very small distances. This leads to the objection of the shuttle and the missile, and it is clear that it is impossible from the moment when we consider the existence of the missile based on what is shown on the time-space diagram. The principle of relativity of simultaneity at the physical level, as it was formulated, leads us inevitably to this interpretation of things. Besides, we realize, as we take into account the existence of the missile, that it leads to two mathematically contradictory reasoning (see my book and the attached text). Also, we will see further that the idea of relativity of simultaneity at the physical level is necessary in order to make it theoretically possible with general relativity, and the semi-closed time loops. It is implied by the formalism of the two relativity theories: the invariance of the speed of light, admitted as an assumption, which is the cause. This is the origin of a new concept of time found, for example, in the twins paradox. But, in fact, the comparison of durations can be dealt very well with a completely different perspective. Indeed, it will be understood later, that although I will not really approach this issue in this letter, that two "identical" clocks, placed in different spatial conditions, can rotate very well simultaneously at different rates.
(B) The relativity of simultaneity at the physical level, once posited, cannot be refuted in a theoretical way by a thought experiment, because in an operational way, we cannot know exactly what is simultaneous and what is not.
The relativity of simultaneity at the physical level is a principle which, once posited, must be assessed in a purely theoretical way by an experience of thought. Indeed, in an operational level, we can not really know what is simultaneous and what is not. Nevertheless, it can be shown that the relativity of simultaneity at the physical level leads to contradictions, that there is necessarily an absolute simultaneity due to the absence of a third possibility. There is not third possibility, because when the station observer and the observer for the train are at the same distance from both light sources, assuming that the ray of light exists to the observer from the station, or it exists also to the observer of the train, or not. In order to be able to assess theoretically, it is enough to consider that the light ray at the rear of the train - while the two observers are at the same distance from the light sources - exists to the observer of the station but not to the observer of the train, then to see the consequences of this taken position.
Strictly speaking, an observer who accelerates, within the special relativity, can not go back in time, except along the line of simultaneity, for events taking place very far "behind him" - passing from one line of simultaneity to another -, what can be analyzed as a rotation, during his acceleration, of his line of simultaneity (6). The special relativity considers the invariance of the speed of light in reference to the inertial observers, without asking if this will lead to a contradiction for the observers who accelerated. I point out that it is not required to look at the moment of acceleration in order to reach the shuttle and missile objection. We need only to consider that it is contradictory to say that the missile existed to the shuttle before the acceleration of the latter and to state later that, in certain cases, it did not yet existed to the shuttle after its acceleration. However, this is implied by the principle of the relativity of simultaneity at the physical level, as described above. Taking into account the existence of the missile based on what is shown on the achieved space-time diagram, as I have already pointed out, in some cases, to two mathematically contradictory reasoning (7). This means that there can be no relativity of simultaneity at the physical level and - since there is no third possibility - which an absolute simultaneity necessarily exists. This can lead physics to an important paradigm shift with regard to its representation of space-time and its approach to the movement.
The absolute simultaneity, at the physical level, cannot also verified immediately, but it can be demonstrated, theoretically, that we are necessarily in this case. Certainly, if, from an operational point of view, we realized that the speed of light is in some cases not invariant, it would be required to conclude that there something is not right in the theory. But since this experience is difficult to achieve, the risk is to remain in an inadequate theoretical context as long as we have not managed to measure this difference in speed. However, even without measuring the speed difference, this mathematical inconsistency can be already demonstrated, if you look at what is conceptually implied, by the theory of special relativity. This conceptual aspect is taken over by the general relativity; it is one of the elements which will theoretically make possible the semi-closed time loops.
C) The relativity at the physical level is also present in general relativity. This is one of the fundamental principles that theoretically make possible semi-closed time loops.
Indeed, if there is an absolute simultaneity at the physical level, and therefore there is present moment for the universe, it is impossible to go back in time. Marc Lachieze-Rey, in his very informative book in French “Time travel: modern physics and temporality -Voyager dans le temps: la physique moderne et la temporalité”, studies the consequences of the formalism of the general relativity. He points out that this last makes theoretically – possible the semi-closed time loops – as the example case of a billiard ball which could theoretically hit his double in his past. It is to move very quickly to say that there is no paradox, because we would end up with two billiard balls instead of just one billiard ball. It is due to the implicit presence of the principle of relativity of simultaneity at the physical level, that at a given moment the theory loses its footing and leaves into science fiction.
Marc Lachieze-Rey, in his book, studied several theoretical possibilities of time loops; I leave it to the wisdom of the physicists or mathematicians to comment. But even if someone is unable to follow the mathematical reasoning, the semi-closed time loops could be approached by asking oneself on which conceptual principles they are based. For some types of time loops, Marc Lachièze-Rey speaks of acceleration, curvature of space and wormhole. I wondered, on this basis how it is possible for a body to go back in time according to the theory.
Here how I understand things, by using these three elements:
First, when a body accelerates, based on the principle of relativity of simultaneity at the physical level, the time “is unfolding for the body", but, according to its line of simultaneity for some distant events, it is supposed that the body can go back the time (8).
Then, in the presence of a space curved by a large mass, a body can retrace its steps "without changing the direction". This means that, on the return, it is not necessary to apply the principle of relativity of simultaneity. Therefore, moving back in time, performed along a line of simultaneity during acceleration, would not be canceled.
Finally, with a wormhole as a spatial-temporal shortcut, the body could move very quickly from one region to another and, through this, could reach quickly a distant place in space-time. Therefore it could, in theory; the body can quickly find itself near the regions of space-time for which it has gone back in time, according to its line of simultaneity, during its acceleration.
Therefore, the semi-closed time loops would be theoretically possible in the context of the general relativity. However, the physicists are wondering if they are as such in practice. It is still very surprising that the original principles of the theory allow these semi-closed time loops. There is this possibility of a time curve that would allow me to return to my past, hence the paradox of the grandfather: What would happen if I kill my grandfather before my father was conceived? Of course, it seems like swimming in science fiction. However, this approach would be allowed by some physics equations. But, always according to Marc Lachieze-Rey, there would be something that prevents "to kill my grandfather", namely the principle of consistency; in summary, "none of the theory predictions cannot collide with logic" (9). This argument is not very convincing to me, because it seems to me as way of filling a default of the theory, concerning its fundamental principles, by an addition along the way. We can probably also resituate the general relativity into a larger general context, making semi-closed time loops impossible. Nevertheless, the general relativity formalism would allow them on his own. This can be a good indication about the necessity to reform the theory regarding its basic principles.
« À l’opposé, on peut être plus permissif et – sans ergoter sur la pertinence du contenu matériel – examiner les espaces-temps qui autorisent l’existence de boucles temporelles. Soit parce que l’on estime que cela n’entraîne en fait aucun paradoxe insurmontable (ce qui, dans une certaine mesure, semble être le cas) et que l’on peut très bien s’accommoder d’une théorie qui les autorise. Soit que l’on reconnaisse que cette existence peut poser problème dans la théorie, et qu’elle constitue ainsi une motivation pour la réformer. » Marc Lachièze-Rey, Voyager dans le temps : la physique moderne et la temporalité, page 199, Science ouverte Seuil.
“By contrast, we can be more permissive and - without quibbling about the relevance of the material content - and review the time-spaces that allow the existence of time loops. Either because it is thought that this does not lead to any insurmountable paradox (which seems to be the case to some extent) and that we can accommodate very well a theory that authorizes them. Or to recognize that this presence can be a problem in the theory, and it constitutes thus a motivation to reform”. Marc Lachieze-Rey, in his very informative book in French “Time travel: modern physics and temporality -Voyager dans le temps : la physique moderne et la temporalité ”, 199, Science ouverte Seuil éditions.
In the exchange appearing on https://www.youtube.com/watch?v=Ya0EU6jINiQ and where Étienne Klein is present, we feel that he, with reason; do not believe that the existence of semi-closed time loops would be possible. But we can use with profit the state of art prepared by Marc Lachièze-Rey in order to advance in the discernment. Therefore, it can be quite beneficial for both parties to continue their discussion on this subject.
From these considerations, it is clear that the principle of relativity of simultaneity at the physical level is present, at least implicitly, in the two theories of the relativity, even if, at a given moment, the physicists do not realize it any more. This illustrates that it is crucial to reform this theoretical framework in depth, by demonstrating that there is necessarily an absolute simultaneity at the physical level, with the consequent consequences that this entails, on the invariance of the speed of light (10), the representation of the space-time and the motion analysis. And physics theorists should not miss this issue still for a significant number of years. It is sufficient that theorists, such as Étienne Klein or Marc Lachièze-Rey, who are particularly called upon in this letter, or others, to seize this issue, so that this question would be definitively resolved.
Respectfully yours, for your work.
Philippe de Bellescize
(1) Does time really exist, or it presents just a concept? Marc Lachièze-Rey TEDx Chambery https://www.youtube.com/watch?v=9BEAGS5TnDY
(2) Limits of a purely operational approach to things, if we want to think about the physical world, and more especially here about the simultaneity:
Opérationnalisme: "Pour les tenants de cette philosophie, un symbole (par exemple une équation) n'a de sens physique que dans la mesure où il se rapporte à l'une des multiples opérations humaines possibles; il s'ensuit que la physique ne concerne pas la nature mais certaines opérations (essentiellement des mesures et des calculs)" Mario Bunge, "Une philosophie de la physique" page 13, Seuil 1975.
Operationalism: “For the advocates of this philosophy, a symbol (for example an equation) has a physical meaning only in so far as it relates to one of the many possible human operations; it follows that physics does not concern the nature but certain operations (essentially measurements and calculations) " Mario Bunge," A philosophy of physics-Une philosophie de la physique "page 13, Seuil editions, 1975.
It is not because two events were perceived as simultaneous that it means they were simultaneous.
This is not because we can not know if two events were simultaneous, that it means they were not simultaneous.
This shows that an approach, which is only operational to simultaneity, is insufficient. It is a question of assessing the conceptual framework in which we are dealing with the relativity. However, this conceptual framework, in regards to time, is based at least at its origin, on the relativity of simultaneity. Einstein, in his thought of the train experiment, starting from an operational approach, speaks about the relativity of simultaneity. He does not say, explicitly, what this implies physically: the invariance of the speed of light implies the relativity of simultaneity at the physical level, as defined in the last paragraph within section A).
(3) On this subject, I quote part of the note 17 of my book And if Einstein was wrong on a crucial point in his analysis leading to the special relativity? - Et si Einstein s’était trompé sur un point capital dans son analyse aboutissant à la relativité restreinte? but it is a point that could be explained probably from a mathematical point of view:
With the absolute simultaneity, the speed of light can no longer be invariant in all events. Indeed, in the experience of the Einstein train, if we consider that the two light rays were emitted simultaneously for the two observers while the latter were at the same point, we know that they will arrive simultaneously for the station observer and not to the observer of the train. Therefore, the relative speed of the two light rays is not the same with reference to the two observers (17).
17- If we consider the context of an absolute simultaneity and that one considers that the time unfolds more or less quickly for an observer, this does not change the nature of the evoked problem. For example, if it is estimated that the time of the train observer slows down in comparison to that of the train station observer, this means that the time of the train observer - required for the light ray emitted at the front of the train to reach the observer of the train- is increased, but then it is also necessary to increase the time that is required for the ray of light emitted at the rear of the train to reach the same observer. Therefore, this does not cancel, for the observer of the train, the speed difference between the light coming from the front of the train and the light coming from the rear of the train. So the issue of the invariance of the speed of light with reference to the observer of the train can not be solved through this means. We could also consider that the distances shorten for the train in the direction of the walking and lengthen in the opposite direction, but the train does not have two different dimensions. So, if we consider the latter entirely, the speed of light can not be invariant in all cases.
(4) There is no instantaneous speed, because in the moment there is no movement. When measuring a speed, it is always the mean speed between two points. However with the special relativity, assuming that the speed of light between two points is not only an average speed, but also an invariant constant speed (the assumed invariance of the speed of light in vacuum). And this invariant constant speed, to different inertial frames of reference, implicates the relativity of simultaneity at physical level, such as it is defined below in the last paragraph within the section A).
It has been found, with the experience of Michelson and Morley, that the speed of light is invariant with respect to the Earth, at least under certain conditions and in the vicinity. As the Earth is a moving body, the idea defended by the special relativity is to generalize what is true for the Earth to other bodies in the "state of inertia". But, in fact, it is absolutely not necessary since there are other possible solutions. From my side, I am studying a relational approach of space and motion, in which there would be a constant adaptation of the speed of light to the spatial configuration.
(5) The text attached to “Einstein's interpretation error - L'erreur d'interprétation d'Einstein” clarifies this point. To speak about the relativity of simultaneity at the physical level is the equivalent to say that the same body exists “to - vis-à-vis” an observer and not “to - vis-à-vis " other, whereas the two observers are " the same position ". But, a body does not exist only “to - vis-à-vis ". Indeed, either it exists in the physical universe, or it does not exist. In the first case, it is the equivalent to saying that it exists “to" all the other bodies of the physical world. This means the absence of relativity of simultaneity at the physical level, and therefore the presence of absolute simultaneity at the physical level, since there is no third possibility. There is no third possibility, since, from the moment where we consider that such a body exists “to" A, either it exists also “to" B, or not. But rather than opposing one metaphysical conception to another, we can consider the context of the relativity of simultaneity at the physical level and observe what this will involve in the reasoning. This leads to the objection of the shuttle and the missile, and it is clear that it is impossible from the moment when we consider the existence of the missile based on what is indicated on the time-space diagram.
(6) To refer to the attached text “Einstein interpretation error - L’erreur d'interprétation d'Einstein” or to my last book.
(7) To refer to the text attached to Einstein's interpretation error .
One of my interlocutors, who may recognize himself, called into question the point 2 of the back cover of my last book:
L’affirmation du point 2 de votre présentation rapide, selon lequel « l’accélération d’un corps conduit à une rotation de sa ligne de simultanéité qui l’amène parfois à remonter le temps », est incorrecte (elle ne reflète pas ce que dit la relativité restreinte sur le sujet).
The statement in point 2 of your quick presentation, according to which "the acceleration of a body leads to a rotation of its line of simultaneity which sometimes leads it to go back in time", is incorrect (it does not mirror what special relativity says on the subject).
This is not exactly what is said on the back cover. In the context of the special relativity, the body goes back in time, in some cases, only by following a line of simultaneity, for events that are situated very far behind it. It is only in the context of general relativity, if we look at what Marc Lachièze-Rey says in his book “Time travel: modern physics and temporality - Voyager dans le temps: la physique moderne et la temporalité”, that it is possible - if we follows the theory - to take an effective trip back in time(see section C).
(8) Nantes Utopiales from November 1st to 6th 2017 LA FLECHE DU TEMPS https://www.youtube.com/watch?v=Ya0EU6jINiQ
(10) With the idea of absolute simultaneity, it is understood that there is a constant adaptation of the speed of light to the spatial configuration, a body of large mass is modifying this configuration. So, in the presence of a low mass moving object in the space, in some cases, there should be a difference in the speed of light if we take for reference two sufficiently distant points of the object . Of course, it is necessary to wonder whether, from an operational point of view, we can achieve a significant measure. This constant adaptation of the speed of light to the spatial configuration is consistent with a relational approach of space and movement. I provide some elements, in my last book, concerning my philosophical positioning on this subject.