Induction Ceremony, 13 April 2000


		 David A. Rabson, University of South Florida



    According to Faraday, induction relates the curl of the electric field
    to the


time rate of change of the magnetic field, as demonstrated in this-here
device....


Oh, I'm sorry: wrong induction ceremony.


    I wish to congratulate you, the new inductees into , on your accomplish-


ment and to encourage you "to advance and diffuse the knowledge of physics,"


as it says on the physical-society membership card.  I've always wondered,
if


the knowledge of physics diffuses, why do we have to work so hard to learn
and


to teach it?


    It is customary at an academic exercise such as this for a Greek-letter
    soci-


ety to recite a passage in a classical tongue.  Unfortunately, the only
classical


language I know how to fake is Latin, but I got some coaching in Greek, so
here


goes:

		    ffio & o sso"AEoeo"! ff  "! o j fl"j   ;


attributed to Archimedes:  "Give me a place to stand, and I will move the


Earth." The lever, the water wheel, and the textbook "Archimedes's
principle"


of displaced volume have indeed moved, if not the Earth, then the
civilizations


that reside on it.  None of you will have trouble coming up with a long list


of physical discoveries and inventions that have changed the world, but let
me


offer a short one: Hooke's law, Newtonian mechanics, electricity, radio,
lasers,


nuclear energy, the transistor, and as we learned in a physics colloquium
earlier


this month, Day-Glow plastic.


    Of course, there's another principle of Archimedes that isn't mentioned
    in


the textbooks.  Already an old man, Archimedes responded to an emergency


call to the defense of his city, Syracuse, against a Roman invasion led by
the


general Marcus Claudius Marcellus. The ramparts, catapults, and machines he


invented were so successful, they held off the Romans for eight months.  If
he


had tried something like that today, the Syracusan national laboratory would


probably have revoked his Q clearance and jailed him on suspicion of handing


state secrets to the Chinese.


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    Unable to take the city by force, Marcellus besieged Syracuse; famine,
    rather


than arms, eventually compelled the surrender. According to legend,
Marcellus


was so impressed by this one man's defense against a Roman legion that he


planned to honor Archimedes and sent a soldier to summon him. Unfortunately,


Archimedes,  deep in thought,  was working out mathematical proofs in the


sand and failed to obey the soldier, who consequently slew him.  I call this


Archimedes's second principle: if a funding agency offers you a grant, don't
turn


it down. I won't mention Archimedes's third principle, but it has something
to


do with running around naked in the streets shouting "ffl'AEaejff!"


    I've been reading students' teaching evaluations,  and apparently people


think that they live in the first generation to get professors who are
eccentric,


ill-dressed, dottering slave-drivers who couldn't explain the lever
principle to a


Roman soldier without invoking ten blackboards full of fractional-order
Bessel


functions of the third kind.  Actually, though, I've checked the history
books,


and there have been hundreds of generations of students putting up with
profes-


sors who are eccentric, ill-dressed, dottering slave-drivers who couldn't
explain


the lever principle to a Roman soldier without invoking ten blackboards full


of fractional-order Bessel functions of the third kind. Let me cite one
example


from Westfall. A student sees his professor walking down the street on
campus


and says "there goes the man that has writt a book that neither he nor any


body else understands."  The campus was Cambridge, and the professor, of


course, was Isaac Newton.


    In the corpus of Newton's work, nothing can match the simplicity and ma-


jestic splendor of the second law:



	  Mutationem motus proportionalem esse vi motrici impressae,


	  et fieri secundum lineam rectam qua vis illa imprimitur;



    I told you I could fake Latin. The crib sheet reads



	  The change in motion is proportional to the motive force


	  impressed, and is made in the direction along the line in


	  which this force is impressed.


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    Some cretin in the textbook department Bowlderized the poetry into



				   F = ma   ;



but you can appreciate in the original phrasing that this idea was of no
merely


practical utility, not just a formula to solve some problem at the end of
the


chapter with levers and inclined planes, but the embodiment of
earth-shattering


revolution that prompted Pope to write his famous epitaph:


	  Nature and nature's laws lay hid in night:


	  God said, `Let Newton be!' and all was light.



    You've probably heard the follow-on:



	  It did not last: the Devil, shouting "Ho,


	  Let Einstein be" restored the status quo.



    Most of my favorite Newton quotes, however, come from the Opticks. I own


an $8 paperback edition printed by Dover. The role of this book in
intellectual


history is perhaps best represented by the fact that my edition has not one
but


three introductions. I quote from the title page: "with a Forward by ALBERT


EINSTEIN, an Introduction by SIR EDMUND WHITTAKER, a Preface by I.


BERNARD COHEN, and an Analytical Table of Contents prepared by" some


graduate student I've never heard of.


    Newton's portrait gazes off to the side and out of the cover in
    blue-tinged


black-and-white, his mouth slightly downturned, almost frowning, as he sits


serenely on a throne-like chair. The nearly black background forms an
overall


impression of eighteenth-century musty reserve.  In the middle of the cover,


however, like Oz landed from a tornado on top of monochrome Kansas, a bold


horizontal band in all the colors of the spectrum spells out the title:
"O-P-T-I-


C-K-S." OK, so physicists don't know how to spell, but I doubt anyone on the


Kansas Board of Education knows how to spell either.


    In Book Two, Part Three, Proposition VIII, Newton reports his
    experiments


on light transmission through hammered gold and observations of a variety of


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other substances that draw him to the conclusion that most of matter
consists


of empty space, or "pores." He writes


	  How bodies can have a sufficient quantity of Pores for pro-


	  ducing these Effects is very difficult to conceive, but per-


	  haps not altogether impossible....  [I]f we conceive these


	  Particles of Bodies to be so disposed amongst themselves,


	  that the Intervals or empty Spaces between them may be


	  equal in magnitude to them all; and that these Particles


	  may be composed of other Particles much smaller, which


	  have as much empty Space between them as equals all the


	  magnitudes of these smaller Particles: and that in like man-


	  ner these smaller Particles are again composed of others


	  much smaller, all which together are equal to all the Pores


	  or empty Spaces between them; and so on...


and here he goes on detailing several more orders of Russian-doll particles
for


almost a page, and then finally


	  And there are other ways of conceiving how Bodies may be


	  exceedingly porous. But what is really their inward Frame


	  is not yet known to us.


    Newton allows himself to speculate further on this theme in the 31st and


final query at the end of the Opticks. He begins by asking whether
undiscovered


forces may be responsible at the smallest scale of particles for the bending
of


light, capillary action, and the very cohesion of matter.  After building
his


argument carefully over many pages, and recalling his quantitative
experiments


on Newton's rings, he works toward the climax:


	  By the Table in the second Part of the second Book, wherein


	  the thicknesses of colour'd Plates of Water between two


	  Glasses are set down, the thickness of the Plate where it


	  appears very black,  is three eighths of the ten hundred


	  thousandth part of an Inch. And where the Oil of Oranges


	  between the Glasses is of this thickness, the Attraction col-


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	  lected by the foregoing Rule, seems to be so strong, as


	  within a Circle of an Inch in diameter, to suffice to hold up


	  a Weight equal to that of a Cylinder of Water of an Inch in


	  diameter, and two or three Furlongs in length. And where


	  it is of a less thickness the Attraction may be proportion-


	  ally greater, and continue to increase, until the thickness


	  do not exceed that of a single Particle of the Oil.  There


	  are therefore Agents in Nature able to make the


	  Particles  of  Bodies  stick  together  by  very  strong


	  Attractions. And it is the Business of experimental


	  Philosophy to find them out.


    In this last sentence, Newton has laid out for the next 300 years the
    reduc-


tionist program of particle physics. I really don't how to analyze or say
anything


intelligent about it; I read his insights and stand in awe.  Any
garden-variety


genius can understand something new; it took Newton to identify correctly


those things that would require three centuries to understand.


    So at this convocation, I welcome you to the business of natural
    philosophy.


It is a business that will take you to some very distant places, to the
centers


of stars and atoms; you will also meet up with certain eccentric characters
(to


be charitable): superconductivity, second sound, anyons, axions, and so
forth.


However, it is a business, I hope, in which you will be able to apply your
knowl-


edge to very practical questions, from how to accommodate the population of


the planet without destroying it to how to get a job when you graduate. I am


pleased to report that this last question has a relatively easy answer:
statistics


show consistently low unemployment and high starting salaries among physics


graduates at the bachelor's, master's, and doctoral levels.


    In your first course, you learned to move weights with levers. In
    qualifying


for admission to , you have found a place to stand. Congratulations.



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