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Illinois Physics Professor Smitha Vishveshwara has been elected to the Executive Committee of the American Physical Society (APS) Division of Condensed Matter Physics (DCMP). By special election, Vishveshwara fills the seat of Richard L. Greene of University of Maryland, who stepped down from the position of chair-elect.

The DCMP chair line typically represents a four-year commitment of service, and each newly elected member generally starts as vice chair for the first year, then serves as chair-elect, chair, and past chair. Vishveshwara will serve as chair-elect starting immediately, and will take over as chair in March 2022.

A new textbook from Cambridge University Press entitled Numerical Relativity: Starting from Scratch, coauthored by Bowdoin College Physics Professor Thomas W. Baumgarte and Illinois Physics and Astronomy Professor Stuart L. Shapiro, explicates this esoteric subfield of physics for today’s students and scientists. The textbook makes heavy use of analogies from Newtonian gravity, scalar fields, and electromagnetic fields. In this way, it introduces key concepts of numerical relativity in a context familiar to readers without prior expertise in general relativity. Readers can explore the concepts presented by working through textbook exercises, and can see them first-hand by experimenting with the accompanying Python sample codes.

Weak-value amplification (WVA) is a commonly used technique in metrology—the study of measurement—that has attracted much recent attention for its promising applications in quantum sensing. First described in 1988 by Aharonov, Albert, and Vaidman, WVA allows scientists to precisely measure extremely small values—or variations in these values—of some quantity of interest, by interfering two quantum states and observing the resulting interference pattern. This technique has a variety of uses, from direct spatial measurements, such as those of velocity or angular displacement, to more exotic ones, such as variations in temperature, chemical concentration, or magnetic field strength.

One great advantage of WVA is that it can be used to minimize many systematic errors that could creep into scientific experiments. Unfortunately, there is a stark trade-off in the quantum experimental setting: amplification of the desired quantity is always offset by a corresponding decrease in the number of detected events. In a quantum optics context, this trade-off manifests as a decrease in detected photon count rate. In a recent paper, physicists at the University of Illinois Urbana-Champaign and their colleagues have experimentally overcome this trade-off without sacrificing photon count rate, by modifying conventional WVA to include a novel photon recycling scheme.