Revisiting the Definition of Speed: Is Distance/Time Arbitrary?

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Discussion Overview

The discussion revolves around the definition of speed, specifically whether defining speed as distance/time is arbitrary and what implications arise from potentially defining it as time/distance. Participants explore theoretical and conceptual aspects of speed, its measurement, and the consequences of redefining it.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • Some participants assert that speed is inherently defined as distance over time and cannot be meaningfully defined as time over distance.
  • Others question the validity of the conventional definition, suggesting that both distance/time and time/distance could be conceptually valid, raising concerns about the implications for existing formulas.
  • A participant highlights that defining speed as time/distance could lead to undefined values when speed is zero, similar to the issues faced with distance/time when time is zero.
  • Some propose that redefining speed could necessitate changes to other physical concepts, such as acceleration, and question whether such changes would lead to inconsistencies.
  • A later reply discusses the potential physical meaning of time/distance in a hypothetical universe, suggesting it could represent the relationship between time and distance in a unique context.
  • Another participant emphasizes that while definitions can be arbitrary, the established usage of terms like "speed" carries significance that should not be disregarded.
  • Some participants express skepticism about whether redefining speed would yield any practical differences in Newtonian systems, while others argue that it would complicate existing equations and concepts.
  • One participant introduces a thought experiment regarding the relationship between time and motion, suggesting a reevaluation of how we understand these concepts in the context of general relativity.

Areas of Agreement / Disagreement

Participants generally disagree on the validity and implications of redefining speed. While some maintain that speed must remain defined as distance/time, others explore the potential for alternative definitions and their consequences, leaving the discussion unresolved.

Contextual Notes

Participants express various assumptions about the implications of redefining speed, including the need to adjust related physical concepts and the potential for undefined values in certain scenarios. The discussion does not resolve these assumptions or their consequences.

  • #61
We need a new word for t/d. I propose "torpidity". Thus, a stationary object would have infinite torpidity; something traveling at an infinite velocity would have zero torpidity.

The weird thing, however, is if special relativity is true, a stationary object would not have infinite torpidity. Just as SR places a speed limit on how fast objects go, SR also places a torpidity limit on how slow objects go. At the speed of light an object travels 3 X 10^8 meters in one second. Thus, a stationary object would have a torpidity of 3 X 10^8 seconds per meter; i.e, a stationary object actually travels 1 meter in 3 X 10^8 seconds.

I think this explains the expansion of the universe.
 
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  • #62
The weird thing, however, is if special relativity is true, a stationary object would not have infinite torpidity. Just as SR places a speed limit on how fast objects go, SR also places a torpidity limit on how slow objects go. At the speed of light an object travels 3 X 10^8 meters in one second. Thus, a stationary object would have a torpidity of 3 X 10^8 seconds per meter; i.e, a stationary object actually travels 1 meter in 3 X 10^8 seconds.

Using t/d, the speed of light would be equivalent to 3.3x10^-9 s/m.
Meaning the minimum amount of time you can cover over one meter is 3.3 nanoseconds, which is equivalent to an upper speed limit.

A stationary object travels an infinite amount of seconds over every meter and in t/d notation this can be reduced to lower limit of 3.3 nanoseconds over every meter.
Which doesn't imply that a stationary object travels one meter every 3 X 10^8 seconds.

Another point is that in relativistic units t/d and d/t disappear.

So 300 million meters per second and 3.3 nanoseconds per meter both become just 1.
 
  • #63
This discussion needs more participation.

We must lower the torpidity of this thread if it is to move forward.
 
  • #64
I believe this thread has run its course.
 

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