Prove Lorentz invariance for momentum 4-vector

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SUMMARY

The discussion focuses on proving the Lorentz invariance of the momentum 4-vector equation $$\frac{dp^{\mu}}{d\tau}=\frac{q}{mc}F^{\mu\nu}p_{\nu}$$. Participants emphasize that demonstrating Lorentz invariance requires showing the equation holds true across all inertial reference frames, specifically through Lorentz transformations. The equation involves the tensor of rank two, ##F^{\mu\nu}##, and the transformation must validate both the original and transformed forms of the equation. This foundational concept is crucial for understanding relativistic physics.

PREREQUISITES
  • Understanding of Lorentz transformations
  • Familiarity with 4-vectors in relativistic physics
  • Knowledge of tensor notation and rank
  • Basic principles of electromagnetism, particularly the role of force tensors
NEXT STEPS
  • Study the properties of Lorentz transformations in detail
  • Learn about the implications of 4-vector notation in special relativity
  • Explore the mathematical formulation of tensors, specifically rank two tensors
  • Investigate the relationship between force tensors and momentum in relativistic contexts
USEFUL FOR

This discussion is beneficial for physics students, particularly those studying special relativity, as well as educators and researchers focused on the mathematical foundations of relativistic mechanics.

flintbox
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Homework Statement


I am meant to show that the following equation is manifestly Lorentz invariant:
$$\frac{dp^{\mu}}{d\tau}=\frac{q}{mc}F^{\mu\nu}p_{\nu}$$

Homework Equations


I am given that ##F^{\mu\nu}## is a tensor of rank two.

The Attempt at a Solution


I was thinking about doing a Lorents transformation to this four vector, but I don't know what this would yield.
 
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flintbox said:
I was thinking about doing a Lorentz transformation to this four vector, but I don't know what this would yield.
Well then why not try it? When we say that an equation is Lorentz invariant, what we mean is that it holds true in all (inertial) reference frames accessible via a Lorentz transformation. So, that means that you have to show that if
\frac{dp^{\mu}}{d\tau}=\frac{q}{mc}F^{\mu\nu}p_{\nu}
then
\frac{dp^{\mu'}}{d\tau}=\frac{q}{mc}F^{\mu'\nu'}p_{\nu'}
is also true.
 
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Fightfish said:
Well then why not try it? When we say that an equation is Lorentz invariant, what we mean is that it holds true in all (inertial) reference frames accessible via a Lorentz transformation. So, that means that you have to show that if
\frac{dp^{\mu}}{d\tau}=\frac{q}{mc}F^{\mu\nu}p_{\nu}
then
\frac{dp^{\mu'}}{d\tau}=\frac{q}{mc}F^{\mu'\nu'}p_{\nu'}
is also true.
You're right! Thank you so much.
 

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