Why does time only move forward and not backwards?

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Discussion Overview

The discussion revolves around the question of why time appears to move only forward and not backward. Participants explore various theories, concepts, and interpretations related to the nature of time, entropy, and the philosophical implications of time's direction.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Philosophical

Main Points Raised

  • Some participants suggest that the concept of time is closely linked to entropy, where systems evolve from order to disorder.
  • Others argue that time may be an illusion, with no real connection to entropy, and that it is merely a measure of durations between events.
  • A participant challenges the notion that entropy is a measure of disorder, emphasizing its definition in terms of energy and temperature.
  • There are differing views on whether time can be reversed, with some asserting that time reversal is connected to entropy, while others question the validity of this connection.
  • Some participants express confusion over the implications of time's direction and the philosophical nature of the question, suggesting that it may not be strictly scientific.
  • One participant notes that the question of time running backward is ill-defined and raises concerns about what it would mean to measure time in reverse.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of time or its direction. Multiple competing views remain, with ongoing debate about the relationship between time and entropy, as well as the philosophical implications of time's flow.

Contextual Notes

Some discussions touch on the limitations of definitions and the philosophical aspects of time, which may not align with scientific perspectives. The conversation also reflects varying interpretations of time's direction and its measurement.

  • #31
Stavros Kiri said:
You did that not me
I am not the one who wrote "proven wrong".
 
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  • #32
jbriggs444 said:
I am not the one who wrote "proven wrong".
Yes, for your original statement, which later on I assume you realized its falsity: in reversed time, circles go inward (to a decreasing and not increasing entropy), while you said always outwards ... . Simple.
 
  • #33
Stavros Kiri said:
Yes, for your original statement, which later on I assume you realized its falsity: in reversed time, circles go inward (to a decreasing and not increasing entropy), while you said always outwards ... . Simple.
The original statement was and is correct.

Edit to add... Your objection appears to have been that there is only one correct labeling for past and future. My suggestion is that if we are to give meaning to the notion of "time flowing into the future", one approach is to note that the labeling is arbitrary.

However, as we both agree, operationally the result is the same. The observable progression for inhabitants of a time-reversed universe is indistinguishable from that for a time-normal universe. Time still "flows" from the direction of low entropy to high entropy.

We both agree that one might as well label the direction of low entropy as "past". It would appear that our disagreement is purely about words and not about physics. However, I dislike to see "proven false" applied to a disagreement about words.
 
Last edited:
  • #34
It's not just about words.
jbriggs444 said:
Time still "flows" from the direction of low entropy to high entropy.
Is incorrect, if you switch "past" and "future". Just make yourself a simple diagram and think carefully.
 

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