Spatially separated events are time relative but .

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    Events Relative Time
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Discussion Overview

The discussion revolves around the relativity of simultaneity and the nature of causality in the context of spatially separated events. Participants explore the implications of special relativity on how events are ordered in time, particularly when they are causally connected or disconnected. The conversation touches on theoretical concepts, philosophical implications, and examples illustrating these ideas.

Discussion Character

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

Main Points Raised

  • Some participants assert that while spatially separated events are time relative, causally connected events maintain a consistent order across all frames of reference.
  • Others argue against the notion that all events are necessarily causally connected, suggesting that events can be causally disconnected depending on their spatial separation.
  • A participant questions how to reconcile the concept of time delay in special relativity with the idea that time is not an objectively existing property of the universe.
  • There is a discussion about the implications of the block universe theory, where perceived time passage may vary based on spatial points, leading to confusion about simultaneity.
  • Examples are provided, such as car crashes occurring in different locations, to illustrate how events can appear simultaneous to one observer but not to another, raising questions about causality and perception of time.
  • Some participants emphasize the need to understand these concepts relative to the observer's frame of reference, contrasting Newtonian intuitions with Einsteinian perspectives.

Areas of Agreement / Disagreement

Participants express differing views on the nature of causality and simultaneity, with no consensus reached on whether all events are causally connected. The discussion remains unresolved regarding the implications of these concepts in the context of relativity.

Contextual Notes

Participants highlight the complexity of reconciling intuitive notions of time with the relativistic framework, indicating that the understanding of causality and simultaneity may depend on the definitions and assumptions made about events and their relationships.

  • #31
Pleonasm said:
A psychic informes me that a specific Sofie will marry me after he tells me this - A. Prompting me to get curious, contact a specific Sofie - B. Sofie proposes to me and we get married ( I fall in love over the phone) - C.

A is not connected to C?

If the time between A and C was a year (for you) then A is causally connected to all within a light year of A at the time of C, everything outside that distance at that moment is "elsewhere".
 
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  • #32
Pleonasm said:
I guess we will find out. He did write: "is not transitive" instead of "not neccesarily".
That is correct, the relationship is not transitive. Here is a brief introduction about what it means for a relationship to be transitive: http://en.wikipedia.org/wiki/Transitive_relation

You are thinking of antitransitivity which is a stronger statement: http://en.wikipedia.org/wiki/Intransitivity

Causality is not transitive, but it is not antitransitive. I was not claiming antitransitivity.

If you are given only that A is causally connected to B and B is causally connected to C then you do not have enough information to determine if there is a causal connection between A and C. For instance, the causal connection could be that A caused B and B caused C, in which case A would be causally connected to C. But the causal connection could be that A was caused by B and C was caused by B, in which case A might not be causally connected to C.

This is relevant because it shows the problem with this argument:
Pleonasm said:
if you at the same time take the view of causality being a fact since the beginning of universe, entailing that all events are by necessity causally connected to each other
This argument relies on causality being a transitive relationship. You are claiming that every event is causally connected to the big bang, and therefore causally connected to each other. But this only works if "causally connected" is a transitive relationship, which it is not.
 
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