In his opening lecture at the 2004 SLAC Summer Institute on Nature's Greatest Puzzles, Chris Quigg challenged participants to propose additions to the ten puzzles around which the school was organized. Here are their responses . . .

The organizers devoted one day of the summer institute to each of the ten themes,

Where and What is Dark Matter?
How Massive are Neutrinos?
What are the implications of Neutrino Mass?
What are the Origins of Mass?
Why is there a spectrum of Fermion Masses?
Why is Gravity So Weak?
Is Nature Supersymmetric?
Why is the Universe made of Matter and not Anti-Matter?
Where do Ultra High Energy Cosmic Rays Come From?
Did the Universe Inflate at Birth?

The NNP Challenge: Propose a question not on the SSI2004 list, and explain briefly why it belongs in the pantheon of Nature's Greatest Puzzles.

The reward for the Best Eleventh Question: A bottle of California's finest sparkling wine and untold fame: an eleven-minute talk to present your question at the Wednesday, August 11, Discussion Session.

The winning entry was submitted by SLAC graduate student Yasaman Farzan, for her question about the validity of Poincaré invariance. Padova student Marco Zanetti and UCSD/Colorado State student Thomas Topel received special commendations for their questions on the nature of time and the mechanism that breaks the strong--electroweak symmetry. Their prizes are copies of Peter Galison's recent book, Einstein's Clocks, Poincare's Maps: Empires of Time.

Yasaman's trophy is shown below. It bears the autographs of SLAC notables Jonathan Dorfan, Persis Drell, Sid Drell, Vera Luth, Martin Perl, and Burton Richter; HEPAP Chair Fred Gilman; SSI organizers JoAnne Hewett, John Jaros, Tune Kamae, and Charles Prescott; and Chris Quigg, issuer of the 2004 SSI Challenge.

Thanks and congratulations to all who entered the Challenge!