Re: a relativity question

[Jack Uretsky <jlu@HEP.ANL.GOV>]

        I understand that the answer is correct IF you reason it correctly
(1/2 of the deflection of light by the sun), but what is it that "pushes"
the photon up?  In other words, it's a bad analogy.
        Part of what system?  (I agree with the conclusion)

On Mon, 25 Nov 2002, Bernard Cleyet wrote:

> Small (change in wave length), but easily detected by Mössbauer.    [Misner, Thorn and
> Wheeler. 1973,  p. 1056, ff.]
>
> bc  who thinks the spring will also have a greater mass, as it's
part of the system.
> Jack Uretsky wrote:
>
> > Ahh, yes.  But now use that argument to calculate the change in wave
> > length?
> >
> > On Mon, 25 Nov 2002, Bob Sciamanda wrote:
> >
> > > Does not a photon change mass/energy/wavelength/color as it climbs the
> > > gravitational potential hill of the earth?
> > >
> > > Bob Sciamanda (W3NLV)
> > > Physics, Edinboro Univ of PA (em)
> > > trebor@velocity.net
> > > http://www.velocity.net/~trebor
> > > ----- Original Message -----
> > > From: "John Mallinckrodt" <ajm@CSUPOMONA.EDU>
> > > To: <PHYS-L@lists.nau.edu>
> > > Sent: Monday, November 25, 2002 9:49 PM
> > > Subject: Re: a relativity question
> > >
> > >
> > > | >A question in Giancolli asks: Is a compressed spring more massive than
> > > the
> > > | >relaxed version of the spring.
> > > | >
> > > | >I understand that Work has been done and there is no change of KE.
> > > | >Classically we say there is now PE stored. But it seems that to conserve
> > > | >energy in the relativistic sense that there would be added mass ...
> > > |
> > > | Yes
> > > |
> > > | >... measured.
> > > |
> > > | Unlikely!
> > > |
> > > | >If so, I wonder if the same would be said of an elevated mass?
> > > |
> > > | No; an elevated mass does not "have" more energy despite the
> > > | implications of standard textbooks (and not to mention the usefulness
> > > | of that gentle subterfuge in many common situations.)  Gravitational
> > > | potential energy is a property of a *system* of interacting masses.
> > > |
> > > | For instance, consider the system consisting of the Earth and all of
> > > | its immediate neighboring objects including my car, Martha Stewart,
> > > | and the ionosphere.  If you reach in from outer space, lift my car
> > > | some distance, and then remove your (lengthy!) arm safely back into
> > > | the cosmos, the rest energy of the system--and, therefore, its
> > > | mass--has been increased.  My car's mass may also have changed (as a
> > > | result, perhaps, of heat conducted to or from your hand while
> > > | lifting), but not because of the energy of interaction between it and
> > > | the Earth.
> > > |
> > > | --
> > > | John Mallinckrodt        mailto:ajm@csupomona.edu
> > > | Cal Poly Pomona          http://www.csupomona.edu/~ajm
> > > |
> > > | This posting is the position of the writer, not that of SUNY-BSC, NAU or
> > > the AAPT.
> > >
> > >
> > > ---
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> > > This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.
> >
> > --
> >         "What did Barrow's lectures contain?  Bourbaki writes with some
> > scorn that in his book in a hundred pages of the text there are about 180
> > drawings.  (Concerning Bourbaki's books it can be said that in a thousand
> > pages there is not one drawing, and it is not at all clear which is
> > worse.)"
> >                                         V. I. Arnol'd in
> >                                 Huygens & Barrow, Newton & Hooke
> >
> > This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.
>
> This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.

--
        "What did Barrow's lectures contain?  Bourbaki writes with some
scorn that in his book in a hundred pages of the text there are about 180
drawings.  (Concerning Bourbaki's books it can be said that in a thousand
pages there is not one drawing, and it is not at all clear which is
worse.)"
                                        V. I. Arnol'd in
                                Huygens & Barrow, Newton & Hooke

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.