"Quantum Accuracy and Quantum Fuzziness" by James Thompson (JILA)

Thursday, November 12, 2015 - 4:00pm to 5:00pm
Physics and Astronomy Colloquium

Thursdays, 4:00-5:00 pm

1-434 Physics and Astronomy (map)
Reception from 3:30-4:00 p.m.
(unless otherwise posted)

Guest Speaker: James K. Thompson (JILA and University of Colorado Boulder)

Talk Title:  “Quantum Accuracy and Quantum Fuzziness”


The Heisenberg uncertainty principle tells us that quantum objects are fundamentally fuzzy.  Despite this fuzziness, some of the most precise and accurate measurements are achieved using quantum objects such as atoms or molecules to measure time, test the roundness of the electron, and sense gravity.  Why? Because quantum mechanics also provides the much less trumpeted “quantum certainty principle”, that if prepared in the same environment, all atoms or molecules of a given type are the same.  This identicalness is the key to achieving high accuracy measurements.  How then can we best take advantage of  quantum certainty while mitigating the quantum fuzziness in order to simultaneously achieve both accuracy and precision?  My talk will discuss efforts to generate quantum connections between atoms so that the atoms conspire to partially cancel each other’s fuzziness, in our latest work by a factor of 60 beyond the standard quantum limit.  If time permits, I will also discuss superradiant lasers with the potential to overcome thermal fuzziness in the laser cavity’s mirrors— a decades old challenge.  Such a laser might achieve a sub-millihertz linewidth,  equivalent to realizing a ruler that could extend all the way from the Earth to the Sun.

For more information, contact Jay Hauser

We thank the following people for their contributions to the wine fund for the post-colloquium reception:
Prof. Dolores Bozovic, Prof. Mike Cornwall, Prof. Bob Cousins, Prof. Andrea Ghez, Prof. Karoly Holczer, Prof. Eric Hudson, Robert Huff, Prof. Alex Kusenko, Prof. Myank Mehta, Prof. John Miao, Prof. Roberto Peccei, Prof. Claudio Pellegrini, Prof. David Saltzberg, Prof. Jean Turner and Prof. Ben Zuckerman.

1-434 PAB