Re: left/right symmetry, manifest or not

[Robert Cohen <Robert.Cohen@PO-BOX.ESU.EDU>]

Okay, I can follow it so far.

Now, suppose we can agree on a coordinate system.  In other words, suppose I
give you enough information so that you can reproduce the coordinate system
when you arrive in my room.

Is it now possible to describe, via words, which way it is spinning?  If so,
how?

____________________________________________
Robert Cohen; rcohen@po-box.esu.edu; 570-422-3428; http://www.esu.edu/~bbq
Physics, East Stroudsburg Univ., E. Stroudsburg, PA 18301

> -----Original Message-----
> From: John S. Denker [mailto:jsd@MONMOUTH.COM]
> Sent: Tuesday, August 27, 2002 1:42 PM
>
> Robert Cohen wrote:
> > I have something spinning in my room.  Is
> > it possible to describe, via words, which way it is spinning?
>
> An excellent, well-focussed question.
>
> Feynman discusses this at length in _The Character of Physical Law_
> near the end of chapter 4.
>
> You can tell who's read this and who hasn't, by saying
> "beware left-handed Martians" and seeing who smiles and
> who doesn't.
>
> Anyway:  Two answers:
> 1) The answer is _no_, provided you:
>    -- use just words, i.e. no diagrams, just words you
>       could speak over an ordinary telephone, and
>    -- use just pre-1940 physics (no weak nuclear processes), and
>    -- no outside references (such as the handedness of the Big
>       Dipper, or the rotation of the earth on its axis).
>
> 2) The answer is _yes_ if you disregard any of the provisos
> listed above.
>    -- You can make a big chalk-mark on the floor, an arc with
>       an arrowhead on one end, and say "it's going this-a-way".
>    -- You can tell me to borrow Madame Wu's cobalt-60 decay
>       apparatus and observe the handedness of the beta-decay.
>    -- You can tell me it's rotating the same direction as the
>       earth.