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In this issue:
Beating New Path to Quantum Secrets with Tiny Drums
Colloquium Monday: Using Technology to Keep Other Countries Honest
Alex Chao Receives EPS 2008 Accelerator Prize

SLAC Today

Monday - March 3, 2008

Beating New Path to Quantum Secrets with Tiny Drums

This illustration shows how a "quantum drum" is built, an atom at a time, with a scanning tunneling microscope.
(Image courtesy of Hari Manoharan.)

The X-ray Laboratory for Advanced Materials (XLAM) is a scientific collaboration between Stanford University and SLAC created to explore the quantum nature of materials. The following work was conducted by XLAM researchers, and was originally published in the Stanford Report on February 8, 2008.

Forty years ago, mathematician Mark Kac asked the theoretical question, "Can one hear the shape of a drum?"

If drums of different shapes always produce their own unique sound spectrum, then it should be possible to identify the shape of a specific drum merely by studying its spectrum, thus "hearing" the drum's shape (a procedure analogous to spectroscopy, the way scientists detect the composition of a faraway star by studying its light spectrum).

But what if two drums of different shapes could emit exactly the same sound? If so, it would be impossible to work backward from the spectrum and uniquely surmise the physical structure of the drum, because there would be more than one correct answer to the question.  Read more...

Colloquium Monday

Colloquium to Focus
On Applications of
Signal Technology

(Colloquium poster)
Poster courtesy of SLAC InfoMedia.

In this afternoon's colloquium, John Treichler of Applied Signal Technology, Inc., will present a historical view of how signal processing technology has been used to provide the intelligence needed to protect nations from one another over the past 100 years. Treichler will use examples from the First World War through the Cold War to illustrate the impact that technical intelligence collection can have in the verification of treaties meant to prevent war and, where necessary, in the conduct of war.

The colloquium will take place at 4:15 p.m. today in Panofsky Auditorium. All are invited to attend.

Learn more...

Alex Chao Receives EPS 2008 Accelerator Prize

(Photo - Alex Chao)
Alex Chao

SLAC Professor Alex Chao has won a European Physical Society (EPS) 2008 Accelerator Prize, which recognizes outstanding work in the accelerator field.

"It's a pleasant surprise," said Chao, who didn't realize it was in the works until he received a congratulatory e-mail from the EPS Accelerator Group last week. "It's a great honor to be recognized for past contributions."

The prize recognizes Chao's "ground-breaking and fundamental contributions to accelerator physics" and for contributions to "design and performance of almost every major accelerator project, built or not built, over the past 30 years." 

"Perhaps they should say built, not built and half-built," jokes Chao, who spent nine years of his career working on the Superconducting Super Collider.

Chao will receive a medal and certificate at a conference in Genoa, Italy, this June.


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