An experimental physicist who coauthored a 1997 measurement of sound propagation in a Bose-Einstein condensate. A focused laser beam suddenly changed the trapping potential, launching localized density disturbances. Rapid nondestructive images followed their motion and measured the speed of sound as a function of density, testing the collective excitations predicted by Bogoliubov theory.^[ref]

An experimental physicist who led a precision measurement of the hyperfine structure of positronium. The collaboration explicitly measured the bias caused by incomplete thermalization, rather than assuming that newly formed positronium had already reached the gas temperature. Correcting this effect changed the comparison with quantum electrodynamics, illustrating how collision dynamics can limit a precision test of a bound state.^[ref]

Anatoly Spitkovsky developed time-dependent calculations of plasma-filled pulsar magnetospheres using the force-free limit, including cases with a tilted magnetic axis. The simulations determine field structure and rotational energy loss while allowing magnetospheric currents and current sheets.^[ref]

Such calculations test the limits of applying a vacuum-dipole picture to a conducting plasma. The approximation neglects plasma inertia where electromagnetic stresses dominate; it does not assert that the plasma is physically absent.

An experimental optical physicist who coauthored a 1986 demonstration of optical squeezed vacuum. Degenerate spontaneous parametric down-conversion inside a cavity produced reduced fluctuations of an optical quadrature, measured with balanced homodyne detection. The result made a noise level below the vacuum reference a directly measured optical property.^[ref]

An experimental physicist who coauthored an early optical squeezed vacuum experiment. Its balanced homodyne detection compared the field's optical quadrature fluctuations with vacuum noise. The paper distinguishes observed noise reduction from the larger inferred reduction before optical attenuation, showing why propagation losses matter when quantifying squeezing.^[ref]

An optical physicist who developed frequency-resolved optical gating with Rick Trebino. Their 1993 demonstration used nonlinear self-diffraction in glass to obtain a trace resolved in both delay and frequency. The pulse serves as its own gate, so the experiment does not require a separate, shorter reference pulse whose shape is already known.^[ref]

An optical physicist who coauthored the introduction of frequency-resolved optical gating with Daniel J. Kane. The method records a nonlinear optical signal's spectrum while varying the delay between two input pulses. Reconstruction from this two-dimensional trace yields both intensity and phase, allowing an ultrashort laser pulse to be characterized beyond its duration alone.^[ref]

An experimental atomic physicist who measured the Casimir force between conducting surfaces in 1997. His electromechanical apparatus used a torsion pendulum to detect the weak attraction over separations of roughly 0.6–6 micrometres. The experiment tested a consequence of changing the allowed electromagnetic field fluctuations by changing boundaries, connecting quantum electrodynamics to a directly measured mechanical force.^[ref]

Lucien Hardy gave an argument against local hidden-variable theories using logical exclusions among two-particle measurement outcomes, rather than a statistical Bell inequality. The structure combines outcomes forbidden by quantum mechanics with another outcome that remains possible: assigning all the relevant local results in advance cannot satisfy these requirements together. His 1992 paper also examined an additional assumption about Lorentz-invariant elements of reality, keeping the role of that assumption explicit in its comparison with quantum mechanics.^[ref]

Homepage: perimeterinstitute.ca/people/lucien-hardy

Charles H. Bennett and Gilles Brassard proposed quantum key distribution using qubits prepared in two incompatible measurement bases. The sender and receiver disclose their basis choices and retain events with matching bases; they test a sample for disturbance before deriving a key. A simple intercept-and-resend attack illustrates the principle: an eavesdropper choosing a random one of the two bases chooses incorrectly half the time and then causes a wrong retained bit half the time, giving a $1/4$ error rate. This example is an attack analysis, rather than a complete security proof.^[ref]

Don Eigler and Erhard Schweizer demonstrated controlled positioning of individual atoms with a scanning tunnelling microscope in 1990. Their apparatus moved adsorbed xenon atoms across a nickel crystal surface at 4 kelvin and assembled designed atomic structures. The low temperature limited unwanted atomic motion, while the scanning tunnelling microscope supplied both manipulation and subsequent imaging. This connected the ability to observe single atoms with the ability to build a chosen arrangement of them.^[ref]

An experimental condensed matter physicist who, with Don Eigler, demonstrated controlled positioning of individual xenon chemical atoms on a nickel surface in 1990. Their scanning tunneling microscope operated at 4 K: its tip became a tool for constructing arrangements one chemical atom at a time, extending the instrument's role beyond imaging. This established a practical route to studying deliberately assembled structures on surfaces.^[ref]

An experimental nuclear physicist who coauthored a 1964 comparison of allowed and unique first-forbidden beta-decay spectrum shapes. A double-lens spectrometer measured the shapes of several isotope spectra, testing whether their energy dependence followed the simplest transition models. The report concerns specific indium, potassium, rubidium, strontium and yttrium isotopes; its conclusions should not be transferred to an arbitrary isotope without checking the transition.^[ref]

Philip Alan Pincus studies the statistical mechanics of polymers. His 1976 scaling argument explains why a long flexible polymer in a good solvent becomes a nonlinear spring when stretched far beyond its equilibrium size. Stretching suppresses the conformations favored by entropy, while excluded volume prevents the chain behaving like an ideal random walk. In the three-dimensional scaling approximation used in that paper, the restoring force grows as the extension to the power $3/2$, within the strong-extension regime before the chain approaches its full contour length. Thus a weak-extension Hooke's law cannot simply be extrapolated to large extensions.^[ref]

Institutional publication list: mrlweb.mrl.ucsb.edu/~pincus/

A theoretical physicist who studied quantum correlations in ideal gases with Takafumi Kita. Their fixed-particle-number treatment reproduces fermion antibunching from the Pauli exclusion principle and boson bunching associated with the Hanbury Brown and Twiss effect. It also follows how correlations change through Bose-Einstein condensation, connecting particle statistics to measurable pair-detection behavior.^[ref]

A theoretical physicist who, with Kazumasa Tsutsui, derived reduced density matrices for ideal Bose gas and Fermi gas systems with fixed particle number. Their 2016 analysis distinguishes the canonical ensemble from familiar grand canonical ensemble applications of Wick's theorem, making explicit which particle-number assumptions enter calculations of quantum correlations.^[ref]

A particle physicist who authored a worked treatment of the Klein paradox for a spin-zero particle. Solving the Klein-Gordon equation at an electrostatic step requires tracking the sign of the charge current, rather than interpreting every transmitted amplitude as an ordinary positive-energy particle. The example connects boundary matching to the appearance of antiparticle and pair-creation interpretations in relativistic quantum theory.^[ref]

An experimental condensed matter physicist who coauthored an electrical readout method for electron spin states in a quantum dot. Different tunneling rates map the spin information onto distinguishable charge histories, followed by a fast charge measurement. Unlike simple energy-selective readout, this mechanism can work when the electron temperature exceeds the splitting between the states.^[ref]

A theoretical condensed matter physicist who coauthored a microscopic study of interacting electrons in an antidot-based interferometer using the Aharonov-Bohm effect. The calculation treats the electrostatic potential self-consistently, linking charge rearrangement and Coulomb blockade to conductance oscillations. It shows why an observed magnetic-field period need not be explained by counting magnetic flux through one rigid geometric area.^[ref]