Relativistic Momentum: Is It a Vector in Relativistic Energy?

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Discussion Overview

The discussion revolves around the nature of relativistic momentum and its relationship to relativistic energy, particularly whether relativistic momentum can be considered a vector within the context of the relativistic energy equation. Participants explore concepts such as the energy-momentum four-vector and the idea of four-kinetic energy.

Discussion Character

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

Main Points Raised

  • One participant asserts that relativistic momentum is a vector, similar to non-relativistic momentum, and questions how it fits into the relativistic energy equation.
  • Another participant introduces the concept of the energy-momentum four-vector, suggesting it may clarify the relationship between momentum and energy.
  • There is a query about the existence of "four-kinetic energy," indicating uncertainty about its definition or relevance.
  • A later reply suggests that the question about four-kinetic energy implies a lack of familiarity with the relevant literature.
  • Further discussion raises the idea of four-velocity and its connection to four-momentum, but does not reach a consensus on the implications for kinetic energy.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether relativistic momentum and kinetic energy can be classified as vectors in the context of relativistic energy. There are competing views regarding the definitions and implications of the energy-momentum four-vector and the concept of four-kinetic energy.

Contextual Notes

Some participants express uncertainty about the definitions and relationships between relativistic momentum, kinetic energy, and their vector nature, indicating a need for further exploration of the underlying concepts.

jaketodd
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Relativistic momentum is a vector, just as non-relativistic momentum is a vector, right? Part of the relativistic energy equation includes relativistic momentum. See here please: http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/releng.html"

Could the relativistic momentum energy part of the relativistic energy equation be considered as a vector when the equation is computed for total relativistic energy? That is, does relativistic momentum, when taken in the context of relativistic energy as a whole, still have a vector? The answer to this question must be yes, because otherwise, without a vector for some of the relativistic energy, then the object would remain stationary. Another question please: I suppose the relativistic momentum could do without a vector in the context of relativistic energy, but then what would keep the object going...Is the relativistic kinetic energy portion of total relativistic energy a vector? Or, are both relativistic kinetic energy, and relativistic momentum, vectors in the context of computed relativistic energy? Or, I suppose you could simply say: Does relativistic energy, as a whole, have a vector component or components, and if so, what part of the relativistic energy has this/these vectors? Maybe this could sum it up: Relativistic energy must have some vector component because otherwise the object would be stationary, right?

Many Thanks,

Jake :zzz:
 
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bcrowell said:
It sounds like you're asking about the energy-momentum four-vector: http://en.wikipedia.org/wiki/Four-momentum The hyperphysics link you gave doesn't seem to discuss it.

Very good; thank you! Another question please: Is there such a thing as four-kinetic energy?
 


jaketodd said:
Very good; thank you! Another question please: Is there such a thing as four-kinetic energy?

The fact that you're asking that question makes me think that you haven't read the WP article yet...?
 


bcrowell said:
The fact that you're asking that question makes me think that you haven't read the WP article yet...?

So you're talking about four-velocity? I'm not sure if that creates four-kinetic energy or just goes into four-momentum.

Your wisdom please?

Thanks!

Jake
 


Anyone please?
 


Did you read the wiki yet? If so, what's your current understanding of the energy-momentum 4 vector?

If not - do you have some reason why not?
 


pervect said:
Did you read the wiki yet? If so, what's your current understanding of the energy-momentum 4 vector?

If not - do you have some reason why not?

I think I understand it now. I think I just needed to read the article a couple more times for it to set.

Thanks,

Jake
 

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