Transforming Relativistic Kinetic Energy: A Concise Mathematical Trick

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Discussion Overview

The discussion revolves around a mathematical approach to rewriting relativistic kinetic energy in terms of Newtonian kinetic energy, exploring the implications and motivations behind this transformation. The scope includes theoretical considerations and the value of alternative perspectives in physics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant introduces a mathematical trick to express relativistic kinetic energy as a function of Newtonian kinetic energy, suggesting it is a concise representation.
  • Another participant notes the formula for relativistic kinetic energy and questions the utility of the transformation, suggesting it may not reveal interesting physics.
  • Some participants express a desire to explore different perspectives on the issue, emphasizing the importance of broadening understanding.
  • Concerns are raised about the validity of presenting ideas without references or peer-reviewed support, highlighting the standards expected in scientific discussions.
  • There is a suggestion that the discussion may not be scientifically rigorous without proper citations, and the nature of the initial proposal is questioned.

Areas of Agreement / Disagreement

Participants express differing views on the value of the proposed mathematical trick and the importance of supporting claims with references. There is no consensus on whether the transformation is meaningful or useful.

Contextual Notes

The discussion reflects uncertainty regarding the relevance and scientific merit of the proposed mathematical approach, as well as the expectations for substantiating claims in a scientific forum.

quiet
Hi. I have seen a mathematical trick, which allows us to rewrite relativistic kinetic energy as Newtonian kinetic energy, multiplied by a function. The function is concise. It is not a serial development. If anyone is interested I can copy that trick here.
 
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Relativistic kinetic energy is ##(\gamma-1)mc^2##. Newtonian kinetic energy is ##mv^2/2##. So the relativistic kinetic energy is ##2 (\gamma-1)c^2/v^2## times the Newtonian kinetic energy. Although this depends on equating Newtonian mass with rest mass, a topic of occasional debate on this forum so there may be a factor of##\gamma## in there somewhere.

The question is why you'd want to do that. It doesn't reveal any interesting physics as far as I can see. It's just algebra for the sake of it.
 
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What does one want to do? In my case to have different ways of looking at an issue, that is, to widen the look.
 
quiet said:
to widen the look.
What if the other way of looking at it is flawed or doesn't add any value?
 
It is true. That can happen. Only You can judge the uselessness of something like that, in case you get to see it.
 
quiet said:
It is true. That can happen. Only You can judge the uselessness of something like that, in case you get to see it.
Well, if you do end up posting it, be sure to post a link to a peer-reviewed publication (or mainstream textbook) that also shows it. That it the standard we use at the PF for technical discussions. Thank you.
 
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I have not copied the link. Would it be a good idea to remove this thread?
 
quiet said:
I have not copied the link. Would it be a good idea to remove this thread?
I locked it, as we usually don't remove threads. But there is still something of information here: As a scientific website, we can ask scientific questions, as "Does anybody know something about the formal connection between ... and ... or is it of any value?" This might - and I'm not saying it does - give rise to an interesting discussion. To state something without any reference or proof is not a scientific method, except it is something more or less obvious. The subject here is more or less obvious, and the question should have been whether it is of any use, and not implicitly assume it is. Also
quiet said:
If anyone is interested I can copy that trick here.
is not a good point to start with. How should your readers know beforehand? And what does "a trick" mean? Tricks normally achieve something, but this is not obvious here and has been rightfully questioned.

Thread closed.
 
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