According to the OED, a "plethysmograph" is "an instrument for recording
and measuring variation in the volume of a part of the body, or of the
whole body, esp. as caused by changes in blood pressure."
--
Tim Chow tchow-at-alum-dot-mit-dot-edu
The range of our projectiles---even ... the artillery---however great, will
never exceed four of those miles of which as many thousand separate us from
the center of the earth. ---Galileo, Dialogues Concerning Two New Sciences
Plethysmos means increase, multiplication (Greek). It is also used in
medicine and psychlogy for enlargement, increase.
Regards, WM
> What's the origin of the mathematical term "plethysm"? I hear that someone
> suggested this term to Littlewood, but who? And why? And what's the
> etymology?
I believe that the term "plethysm" was introduced in:
MR0010594 (6,41c) Littlewood, D. E. Invariant theory, tensors and
group
characters.
Philos. Trans. Roy. Soc. London. Ser. A. 239, (1944). 305--365
It was suggested to Littlewood by M. L. Clark after the Greek word
plethysmos, for a third type of Schur function
$\pi\lambda\eta\theta\nu\sigma\mu o\zeta$ for "multiplication".
And the function was introduced in Littlewood's "Polynomial
Concomitants and Invariant Matrices", J. London Math. Soc. 11 (1936),
49-55.
Visiting Research Associate
Peirce Edition, Institute for American Thought
902 W. New York St.
Indiana University-Purdue University at Indianapolis
Indianapolis, IN 46202-5159
USA
URL: http://www.irvinganellis.info
I used some of your information to enhance the nLab entry on
plethysm: