Solve Momentum to Get Gamma in Relativity Theory

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Discussion Overview

The discussion revolves around the derivation of the gamma factor in the context of relativistic momentum and energy equations. Participants explore the relationship between momentum, mass, and velocity within the framework of relativity theory.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant notes that substituting the momentum equation into the energy formula leads to the expression E=gamma mc^2, questioning the origin of "gamma."
  • Another participant provides the definition of gamma as 1 over the square root of 1-((v^2)/(c^2)).
  • A participant emphasizes the importance of notation in the equations, specifically mentioning E² = m²c⁴ + p²c² and p = gamma mv.
  • There is a discussion about the definition of momentum, with one participant asserting that momentum is mass times velocity, while another clarifies that in relativistic physics, it is gamma times mass times velocity as velocity approaches the speed of light.
  • One participant questions the validity of combining velocity and the speed of light in an equation, suggesting a potential misunderstanding.
  • Another participant expresses confusion about the concept of velocity equating to the speed of light, indicating a need for further clarification.

Areas of Agreement / Disagreement

Participants express differing views on the definition of momentum in relativistic contexts, and there is uncertainty regarding the manipulation of velocity and the speed of light in equations. The discussion remains unresolved with multiple competing perspectives.

Contextual Notes

Some participants may be missing foundational assumptions about relativistic physics, and there are unresolved questions regarding the manipulation of terms in the equations presented.

gunblaze
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I was reading a book on the theory of relativity yesterday and it said that by substituting the equation for momentum (p=mv) into the formula E^2=m^2c^4+p^2c^2..
i will be able to get this E=gamma mc^2..
I was just wondering where they get the "gamma" from? :confused: can anyone pls tell me how they get that? Thx
sry, not really good at this. :cry:
 
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gamme is equal to 1 over the square root of 1-((v^2)/(c^2))
 
You need to be careful with the notation.

[tex]E^{2}=m^{2}c^{4}+p^{2}c^{2}[/tex]

and [tex]p=\gamma m v[/tex].

Daniel.
 
dextercioby said:
[tex]p=\gamma m v[/tex].

Isn't momentum=mass x velocity?
 
gunblaze said:
But isn't momentum=mass x velocity?

Not in relativistic physics. Its gamma * mass * velocity as v -> c
 
erm.. can we put velocity, v, and speed of light, c, together?
eg: [tex]v^{2}c^{2}=c^{4}[/tex]
 
Last edited:
but it sounds ridiculous rite? how can the velocity be equal to the speed of light?
 
k.. guys, i get it alr..thx thanks so much!
 

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