Calculating the Distance Traveled by Light: Myth or Reality?

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Discussion Overview

The discussion revolves around the equation for calculating the distance traveled by light, specifically questioning the validity of the formula d=tc^2 and its dimensional consistency. Participants explore the implications of using different units of time, such as Planck time, and the mathematical relationships involved.

Discussion Character

  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant asserts that the distance traveled by light can be expressed as d=tc^2, where d is distance in meters and t is time in seconds.
  • Another participant challenges this by stating that the equation is equivalent to distance = time x speed^2, which they argue does not make sense dimensionally.
  • A later reply acknowledges a mistake regarding the units of time, suggesting that Planck time should be used instead of seconds.
  • Another participant reiterates that the equation is dimensionally incorrect, emphasizing that a time multiplied by a speed squared cannot yield a distance.
  • One participant claims that the units do balance and invites others to demonstrate this assertion.
  • Another participant admits to confusion and proposes a different equation, dc^3 = tc^2, indicating a need for a cubed value.
  • Further clarification is sought regarding the dimensional analysis of the proposed equations, questioning the validity of the relationships presented.
  • One participant expresses regret for mixing up equations and acknowledges the late hour affecting their clarity.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the validity of the initial equation or its dimensional consistency. Multiple competing views remain regarding the correct formulation and interpretation of the relationships involved.

Contextual Notes

There are unresolved issues related to dimensional analysis and the proper use of units, particularly concerning the transition from seconds to Planck time and the implications for the equations discussed.

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Is it true that the distance traveled by light during a particular time period is expressed by d=tc^2 where d is the distance traveled in metres and t is the elapsed time in seconds?
 
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Distance = time x speed

What you wrote is the equivalent of distance = time x speed^2. That doesn't make sense.
 
Sorry the time is in Planck time not seconds. My mistake.
 
The Planck time is still a time. The equation makes no sense just on dimensional grounds. A time multiplied by a speed squared doesn't give a distance, regardless of units.
 
Muphrid said:
The Planck time is still a time. The equation makes no sense just on dimensional grounds. A time multiplied by a speed squared doesn't give a distance, regardless of units.

Well it does work. The units all balance.
 
By all means, if the units do balance, then I am here to learn. Show me.
 
Sorry I messed up.

It should be dc^3 = tc^2.

That's where I needed the cubed value.
 
speed = distance / time

Distance x (distance^3)/(time^3) is not equal to (time)x(distance^2)/(time^2), right?
 
Sorry scrub that I have mixed up two sets of equations. It is 12.53 AM here.
 

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