Santa Fe Institute

A Solution Strategy for Hard Problems Inspired by the X-Ray Phase Problem


March 06, 2013
3:30 PM
Noyce Conference Room

Veit Elser (Cornell University)

Abstract.  SFI is my spring break destination from the frozen northland where I occasionally teach the introductory physics course about waves. A standard part of the curriculum deals with computing a diffraction pattern, given a pair of slits of a given size and separation — but not the reverse, i.e. directly computing the structure of the slits from the diffraction pattern. This colloquium begins with a tutorial on solving the reverse problem and puts this in the context of current efforts to image molecules with free-electron x-ray lasers. The principle of the algorithm that solves the x-ray "phase problem," as it is usually called, is remarkably general and has proven to be a powerful strategy for solving a broad range of constraint problems. A sampling of these, from proteins to packings, are described at the end of the talk.

Purpose: Research Collaboration

SFI Host: Cris Moore

More Info

  • * SFI community lectures are free, open, & accessible to the public.
  • * Seminars & colloquia are geared for scientists but free & open to the interested public.
  • * All other SFI events are by invitation only.
  • * Note: We are unable to accommodate members of the public for SFI's limited lunch service; you're welcome to bring your own.

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