Can you modify this quote regarding time dilation?

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Discussion Overview

The discussion revolves around a quote related to time dilation and four-velocity in the context of relativity. Participants explore the implications of the quote, particularly regarding the relationship between movement through space and time, and the concept of traveling into the future.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants express confusion over the last sentence of the quote, questioning its correctness regarding the concept of "going into the future."
  • Concerns are raised about the use of the term "subtract" in the context of movement through time and space, with requests for clarification or modification.
  • One participant argues that the quote assumes an absolute speed through space, while only relative velocities are meaningful.
  • Another participant provides a technical explanation of four-velocity, including its mathematical representation and implications for proper time.
  • There is a mention of the poetic nature of the quote and a comparison to how it might be expressed in a literary context.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correctness of the quote or its interpretation. Multiple competing views remain regarding the implications of the statements made in the quote.

Contextual Notes

The discussion highlights limitations in understanding the concepts of speed through space versus time, as well as the mathematical framework underlying four-velocity and proper time. There are unresolved questions about the clarity and accuracy of the quote itself.

49ers2013Champ
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The total speed of an object through the dimension of space and the dimension of time equals the speed of light. An object moving through space must subtract from its movement through time for the sum to remain at lightspeed. So an object at the speed of light has all its movement through space and its movement through time must equal zero. Inversly a stationary object has all its movement through time and none through space. Making the quickest way to travel into the future is to stop moving.

What parts of this quote need to be modified?

The last sentence seems completely contrary to how I've understood "going into the future." Is this last sentence correct?

The second sentence, when it uses the word "subtract", is what is hard for me to process. Can someone either modify this or explain it in finer detail? Is there a numeral that can represent one's movement through time? And can it be plugged into an equation that allows for it to be subtracted from or added to the "space numeral" so that the equation always equals the speed of light?
 
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49ers2013Champ said:
The total speed of an object through the dimension of space and the dimension of time equals the speed of light. An object moving through space must subtract from its movement through time for the sum to remain at lightspeed. So an object at the speed of light has all its movement through space and its movement through time must equal zero. Inversly a stationary object has all its movement through time and none through space. Making the quickest way to travel into the future is to stop moving.

What parts of this quote need to be modified?

The last sentence seems completely contrary to how I've understood "going into the future." Is this last sentence correct?
Whenever you quote something, you should provide the source.

The subject of the quote is Four Velocity. Do a search and you will quickly see the quote is beyond redemption.
 
49ers2013Champ said:
The total speed of an object through the dimension of space and the dimension of time equals the speed of light. An object moving through space must subtract from its movement through time for the sum to remain at lightspeed. So an object at the speed of light has all its movement through space and its movement through time must equal zero. Inversly a stationary object has all its movement through time and none through space. Making the quickest way to travel into the future is to stop moving.

What parts of this quote need to be modified?

The last sentence seems completely contrary to how I've understood "going into the future." Is this last sentence correct?

The second sentence, when it uses the word "subtract", is what is hard for me to process. Can someone either modify this or explain it in finer detail? Is there a numeral that can represent one's movement through time? And can it be plugged into an equation that allows for it to be subtracted from or added to the "space numeral" so that the equation always equals the speed of light?
The quote assumes there is such a thing as speed through space. The only meaningful speeds are those measured against some other object. So two things may have a relative velocity, but they don't have an absolute velocity individually.

As George pointed out, the thing that describes relative velocity is called the 4-velocity. Look it up on Wiki.
 
49ers2013Champ said:
The total speed of an object through the dimension of space and the dimension of time equals the speed of light. An object moving through space must subtract from its movement through time for the sum to remain at lightspeed. So an object at the speed of light has all its movement through space and its movement through time must equal zero. Inversely a stationary object has all its movement through time and none through space. Making the quickest way to travel into the future is to stop moving.
It is a somewhat poetic discussion of the 4-velocity and 'proper time'.
It might be how Lewis Carroll would describe it had he not predated relativity.
The four-velocity is U^{\mu}=(c\gamma,\gamma\bf v). Its square is
U^2=U^\mu U_\mu=c^2\gamma^2-{\bf v}^2\gamma^2=c^2. The square root of this is what the quote calls the "total speed of an object".
The word "subtract" refers to the minus sign for the space part in the 'length' formula. If v=c, then U^2=0, and equals zero as in the quote. "Travel into the future" refers to the increase of the proper time,
d\tau^2=dt^2-d{\bf x}^2. You can see from that equation that d\tau is maximized if \bf dx=0. This means the twin that never moves ages faster.
 
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