How Does Time Geometry Affect the Concept of Event Simultaneity in Relativity?

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Discussion Overview

The discussion centers on the relationship between time geometry and the concept of event simultaneity in the context of relativity. Participants explore various geometrical frameworks—Euclidean, Riemannian, and Lobatchevskian—and their implications for understanding simultaneity, time travel, and the nature of events in different timelines.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that events can be analyzed using a single time coordinate, simplifying the analysis by treating time as a geometric line in various geometries.
  • There is a suggestion that simultaneity can be defined between events in parallel timelines, but observers cannot confirm this simultaneity due to a lack of information transfer between timelines.
  • One participant argues that in Riemannian geometry, simultaneity has no meaning as all events are serial, while in Lobatchevskian geometry, there can be multiple parallel timelines with a single instance of simultaneity.
  • Another participant introduces the idea of time travel events occurring in parallel universes, but this remains speculative and is not universally accepted.
  • Some participants discuss the nature of antimatter and positrons, with references to Feynman's ideas about time reversal, but there is contention over whether these concepts imply actual time travel.
  • There is a mention of the mathematical duality between electrons and positrons, but it is noted that this does not equate to time travel.
  • One participant introduces the notion of "time power," but this concept is not elaborated upon and remains unclear.

Areas of Agreement / Disagreement

Participants express a range of views on the nature of simultaneity and time travel, with no clear consensus reached. Some ideas are contested, particularly regarding the implications of antimatter and the interpretation of Feynman's work.

Contextual Notes

Participants acknowledge limitations in their assumptions and definitions, particularly concerning the nature of timelines and the implications of different geometrical frameworks on simultaneity.

Who May Find This Useful

This discussion may be of interest to those exploring theoretical physics, particularly in the areas of relativity, quantum mechanics, and the philosophical implications of time and simultaneity.

Antonio Lao
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The Nobel Laureate P.W. Bridgman commented on Einstein’s theories of special and general relativity. He said that more analyses should be given to the events of the theories rather than analytical attacks on the coordinate system used in specifying the physical events found in the theories.

Generally, events are analyzed by the use of three spatial coordinates and one time coordinate. In this discussion, events are only analyzed by the use of one time coordinate.
This method can simplify the analysis tremendously. The time coordinate is assumed to take a form of geometry similar to physical space. This is the extraction of time from the spacetime of relativity and keeping the spatial parts hidden away. In this way, one can define time as a line embedded in the following three geometries: Euclidean (planar), Riemannian (spherical) and Lobatchevskian (hyperbolic).

By parallel timed events, it is to mean that simultaneity can be defined between one event in one timeline and another event in the other timeline. But for an observer in one timeline, he or she is not capable of knowing whether these two events are simultaneous. There is no information send by photons from one to the other. These events can only be assumed to be simultaneous. And that is all one can do. Each photon of each timeline travels along each line and no reason to jump to the other line. Each line contains its own reality.

By serial events, it is to mean that simultaneity has no meaning. All events follow or lead other events. These successions of events gave true meaning to the word “timeline.”

In Euclidean geometry, two parallel timelines can be constructed. The simultaneity of two parallel events is the end points of the perpendicular distance between the lines. In theory, there are an infinite number of simultaneous events. But the following assumptions must be made that (1) the time tick-marks are the same for the lines and (2) that the line are infinitely extended in both directions. The events along one timeline are all serial events.

In Riemannian geometry, parallel events cannot be constructed. Hence simultaneity has no meaning. All events are serial. But a zero time can be defined as located at one of the poles. The other pole will be the end of time.

In Lobatchevskian geometry, many infinitely extended parallel timelines can be constructed. Each of these timeline contains serial events. But there is only one occurrence of simultaneity for these parallel events. And this happens at the same time.
 
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Parallel timed Events?

Antonio Lao said:
ic).

By parallel timed events, it is to mean that simultaneity can be defined between one event in one timeline and another event in the other timeline. But for an observer in one timeline, he or she is not capable of knowing whether these two events are simultaneous. There is no information send by photons from one to the other. These events can only be assumed to be simultaneous. And that is all one can do. Each photon of each timeline travels along each line and no reason to jump to the other line. Each line contains its own reality.

.

In other words do you mean that Time travel events might
be happening at all times but we cannot tell such actions
are taking place as we are in another parallel universe ? :smile:
 
RonRyan85 said:
...Time travel events might be happening at all times...

Sorry for this belated reply. I was preoccupied with the theory development site.

The other timeline I am talking is the one traveled by all the antimatter. And, yes, in a sense, this can be thought of as in another parallel universe. But the vacuum is the connecting link between our universe and this antiuniverse.
 
Antimatter exists in the same time and universe as ordinary matter does. In spite of confusing popular "explanations" of the mathematics of antimatter that imply magical properties for antiparticles, they are not mysterious or contradictory. Quantum field theory would be incomplete if it didn't cover both kinds of particles, and familiar physical facts like radioactivity rely on antiparticles. Among the other particles emitted by the weak interaction is an antineutrino.
 
I think I read somewhere (Feynman?) that an anti-electron or positron can be thought of as an ordinary electron traveling backward in time? If I can find a reference I'll try to return and post it here.
 
rtharbaugh1 said:
I think I read somewhere (Feynman?) that an anti-electron or positron can be thought of as an ordinary electron traveling backward in time? If I can find a reference I'll try to return and post it here.

"Can be thought of" is precisely the problem I was talking about. Feynman knew what he meant, and other physicists know what he meant. The mathematics describing a positron (anti-electron) can be made to be identical to the math describing the electron if you replace the t (for time) by -t. This is an interesting and valuable duality, but time travel it is not.

Feynmann and his former thesis advisor Wheeler liked to play around with wild and crazy ideas. Feymann's time reversal idea was part of what led him to his very valuable sum over histories, or path integral method. But although he discussed a lot of future capabilities (such as nanotechnology), he never wrote about macroscopic time travel.
 
Travel by time, it to use time power.
The time system is power enough first.
 
hey.like said:
time power

Can you please explain this a little bit more? Thanks.
 

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