## Brain Teaser Limericks

Physicists love their limericks. That's what we discovered a couple of years ago when we first requested submissions of science-themed limericks, and received literally hundreds of replies. [Winners appeared on The Back Page of the [March 1997] issue of *APS News*. A complete collection of limericks can be found at /publications/apsnews/features/limericks/index.cfm.] Encouraged by this success, *APS News* announced a second limerick contest last summer, this time requesting verse in the form of "brain teasers" (*APS News*, August/September 1998). The responses this time were not nearly as prolific; nonetheless, some clear winners did emerge.

A note on selection criteria: We adopted a rather liberal interpretation of what constitutes a "brain teaser:" some limericks were intended as cleverly phrased exam questions, others as riddles, still others as standard "brain teaser" story problems. We also allowed some minor divergence from strict adherence to the rules of scansion in the limerick form. Call it "poetic license." It's all in the spirit of fun, after all, and we hope our readers find these entries entertaining, challenging, and perhaps even useful as an educational tool.

*B. Ripin, Editor*

First prize goes to Fred Bortz, physicist and author of numerous science and technology books for young readers [http://www.cherryvalleybooks.com/DrFred], and a self-proclaimed "limerician at large." He offered the following as a replacement to any exam question asking for a description and explanation of the Anomalous Zeeman Effect:

1. The famed mathematiker Riemann

Shared manifold cocktails with Zeeman.

Their degenerate state

Split in six. (They saw eight.)

How anamolous can spectra be, Mon.

Advises Bortz: "It works best when read by a Leighton-type reader affecting a Carribbean accent, accompanied by a Feynman impersonator on bongos."

Kay DeVicci of Moorestown, NJ, submitted several sample limericks, from which we selected the following:

2. The sum of 3 numbers is 4;

The product is (-2) more;

The sum of their squares,

If anyone cares,

Is just 14 less than a score.

For those desiring more of a mathematical challenge, DeVicci's "quadruple limerick" in four parts warrants an honorable mention, not just for level of difficulty, but also for its wry commentary on the meager rewards of mathematical proficiency:

3. Consider a cube for a minute

And imagine the largest square in it.

If you're a math whiz,

Tell me how big it is;

It's tricky to even begin it!

Now let us move up one dimension:

Find the cube of the largest extension

That fits (neatly packed)

Into one tesseract,

And, boy, will you have stress and tension!

Martin Gardner proposed this last question,

And I solved it, at no one's suggestion.

It took 15 years

Of blood, sweat and tears,

And gave me severe indigestion.

My proof fills up 100 pages;

'Til I solved it, it stumpled all the sages.

It was recently checked

And pronounced quite correct,

But it hasn't augmented my wages.

Marion Cohen, a mathematician and writer at Drexel University whose husband is a physicist, credits *APS News* with inspiring her to begin writing math-related limericks. Although her many submissions were more in the line of limerick riddles than brain teasers, we picked one dealing with differential equations - as an honorable mention in our contest:

4. We were known by Dirac and Wigner

But not knowing brings no stigma

'Cause we simply ooze

With n's, m's, and 2's,

And don't forget x and big-sigma.

Maurice Macholver of St. John's University in Jamaica, New York, submitted his own version of a limerick riddle:

5. A real, square matrix named "A"

Asks you, "Is this Yea or Nay?"

If I were orthagonal

And also diagonal

My name would be Delta-IJ.

Finally, Thomas Walnut, emeritus professor of chemistry at Syracuse University, adopted Bortz's approach, submitting a limerick which poses an interesting question and asks for an explanation:

6. The distant planet Gazoo

Has lakes made of helium II

There're some might tough snakes

Who live in those lakes

Can they swim in that very cold goo?

Walnut did not supply an answer, "because I am not sure what it is," although he offered to supply the answer "if pressed." We prefer to let our members figure it out for themselves.

1. ??

2. 1, 1, and 2

3. The side of the largest square in a cube of unit side is the square root of 9/8. The side of the largest cube in a tesseract of unit side is the square root of A, where A is the smaller of the two real roots of: 4 x **4 - 28 x **3 - 7 x **2 + 16 x + 16 = 0. Numerically, sqrt (A) is approximately 1.007435.

4. Legendre functions

5. ??

6. [Your answer here]

**©1995 - 2017, AMERICAN PHYSICAL SOCIETY**

APS encourages the redistribution of the materials included in this newspaper provided that attribution to the source is noted and the materials are not truncated or changed.

**Editor:** Barrett H. Ripin

**Associate Editor:** Jennifer Ouellette