Do we have momentum in traveling in time?

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Discussion Overview

The discussion revolves around the concept of momentum in relation to time, exploring whether time can be treated as a dimension similar to spatial dimensions. Participants examine the implications of time dilation, energy, and the nature of time itself, engaging in both speculative reasoning and technical considerations.

Discussion Character

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

Main Points Raised

  • Some participants propose that time is a dimension with different properties than spatial dimensions, questioning if there is energy associated with traveling through time.
  • One participant suggests that momentum in the time direction could be defined as energy, linking it to the concept of time dilation experienced at relativistic speeds.
  • Another participant speculates on the possibility of time having momentum, but acknowledges the lack of controlled and testable conditions to explore this idea.
  • Concerns are raised about the implications of time having momentum, particularly regarding energy sources and the behavior of time in relation to gravity and motion.
  • A later reply emphasizes the importance of the four-vector approach in modern physics, indicating that the time component of momentum relates to energy.
  • Some participants express uncertainty about the definitions and implications of momentum, particularly in the context of light and mass.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of time as a dimension or its relationship to momentum and energy. Multiple competing views and speculative ideas remain present throughout the discussion.

Contextual Notes

Participants note the challenges in measuring relative time and the potential for thought experiments involving high-speed oscillators or spinning devices to explore these concepts further. There is also mention of the limitations of traditional definitions of momentum when applied to light and time.

1832vin
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this may sound extra ridiculous
there's stuff like time evolution for wave functions, and a lot to do with time
but I've thought, isn't time also a dimension? ( i know it's not a spatial dimension, but does it mean it has completely different properties?)
since we are traveling in time at a constant rate (we presume), as like traveling through spatial dimentions, does it mean there's energy to it? and as you travel close to the speed of light, you experience time less (due to time dilation and others)
then does it mean the higher energy(in spatial dimension) = less energy in time dimension?
traveling at a speed means have energy to accelerate and decelerate other objects
why would we return back to normal time progression after time dialation>? where did we got that energy(time energy?) back?

and where did the energy came from to make us move foward in time?
 
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Momentun in time direction is exactly the definition of Energy.
 
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1832vin said:
this may sound extra ridiculous
there's stuff like time evolution for wave functions, and a lot to do with time
but I've thought, isn't time also a dimension? ( i know it's not a spatial dimension, but does it mean it has completely different properties?)
since we are traveling in time at a constant rate (we presume), as like traveling through spatial dimentions, does it mean there's energy to it? and as you travel close to the speed of light, you experience time less (due to time dilation and others)
then does it mean the higher energy(in spatial dimension) = less energy in time dimension?
traveling at a speed means have energy to accelerate and decelerate other objects
why would we return back to normal time progression after time dialation>? where did we got that energy(time energy?) back?

and where did the energy came from to make us move foward in time?
In my eyes, fundamental questions are never ridiculous. Thanks for questioning and questioning again. We usually don't take the time to ask how all this (our world) works.
 
Strictly speaking, I'd have to venture a no. Light has no weight, and thus no momentum. Time, as far as we know, doesn't have matter. It isn't composed of matter.

In a more abstract sense though, its possible. However, much of this question is relative since we don't have any obvious way to create controlled and testable conditions. Perhaps the passage of time, unbeknownst to us, has been slowing or speeding up since the big bang!

We do know that gravity has some subtle but well known effects on time. Imagine a satellite in a highly elliptical orbit. As it reaches its periapsis (lowest point of orbit), it will be moving away from its parent body for half its journey, and thus experiencing less gravity. If time did have momentum, then with each orbit, time would stretch and compress, spending some form of energy. Without positing some unsupported extra-dimensional banking of time-energy, this behavior should stop as the energy source depletes. I speculate that this doesn't happen.

Okay I'm getting a bit lost with this thought experiment, take it for what's it is - half baked.
 
Right said:
Strictly speaking, I'd have to venture a no. Light has no weight, and thus no momentum. Time, as far as we know, doesn't have matter. It isn't composed of matter.

In a more abstract sense though, its possible. However, much of this question is relative since we don't have any obvious way to create controlled and testable conditions. Perhaps the passage of time, unbeknownst to us, has been slowing or speeding up since the big bang!

We do know that gravity has some subtle but well known effects on time. Imagine a satellite in a highly elliptical orbit. As it reaches its periapsis (lowest point of orbit), it will be moving away from its parent body for half its journey, and thus experiencing less gravity. If time did have momentum, then with each orbit, time would stretch and compress, spending some form of energy. Without positing some unsupported extra-dimensional banking of time-energy, this behavior should stop as the energy source depletes. I speculate that this doesn't happen.

Okay I'm getting a bit lost with this thought experiment, take it for what's it is - half baked.

interesting thought experiment, and I'm going to try expanding on it

but the problem is, that we cannot measure relative time, (well we can, but not in a way that we can compare it)
we might want to make an oscillator that oscillates close to the speed of light, or a spinning device
then we might be able to get some relative time comparisons
 
Right said:
Light has no weight, and thus no momentum.
I assume you mean Mass, here. Light (photons) certainly do have momentum, despite being massless. The momentum of a photon is h/λ so you can see, as it is inversely proportional to wavelength, the momentum gets higher as the frequency (c/λ) increases. Direct evidence of this is Light Pressure (look it up).
The definition you are using for momentum only refers to the momentum of objects that have mass. That works fine for most purposes, involving mechanical problems.
 
This thread is starting to drift into speculation here.

It is indeed possible and even natural to treat time as a dimension. When we do, we can still describe motion using vectors, except that instead of having three components (x, y, and z) the momentum "four-vector" has four components (x, y, z, and t). This four-vector approach is an important part of the modern formulation of special relativity and is essential to move on into general relativity. And as arivero hinted in post #2 above, when you write the momentum as a four-vector, its time component becomes the energy of the object.

We're leaving this thread open for now, but it would be a good thing if all participants would first google for "momentum four-vector", ask questions about what they don't understand, but not offer speculations that ignore what physicists have already learned over the past century.
 
Yes, I meant mass. And I stand corrected! Silly me with my Newtonian thinking. o0)

I can take a hint Nugatory.
 

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