Re: [Phys-l] E=mc^2 because E=mc^2?

[<carmelo@pacific.net.sg>]

John Denker wrote:
> I also find it amusing just how often people who rely on
> celebrity endorsements use such "data" selectively.  It's
> true that 45 years ago Feynman and his colleagues were
> teaching the idea of speed-dependent mass ... but 35
> years ago they weren't.  What are we to make of that?
> I take it as evidence that Feynman & Co. were capable
> of changing their minds, capable of learning.

35 years ago, Feynman still did not change. You may want to take a look at "Perfectly Reasonable Deviations from the Beaten Track" by Richard Feynman. "It was successful, the necessary consequential phenomena (like mass changing with velocity) were ultimately observed experimentally." p 283. 

Neither do I agree with "The majority has the truth." However, it is a great opportunity for the students to learn about the tentative nature of science.

> There are sound pedagogical and practical reasons for
> preferring the spacetime approach, including simplicity,
> power, elegance, and consistency.  For details on what
> I mean by that, see
>    http://www.av8n.com/physics/odometer.pdf

It seems that this is going back to absolute notion of space and time. The image of Jupiter provided can not be *real*: You have forgotten Doppler Effect!


Alphonsus