A physicist who developed a theory of the stability of multiply twinned particles. The model balances surface, twin-boundary and elastic elastic strain energy, together with adhesion to a supporting surface. Because these contributions scale differently with size, a shape favored for a small particle can become unfavorable as it grows; the calculation predicts critical sizes for stable and metastable structures.^[ref]

A researcher who coauthored atomic-scale studies of metallic nanoparticles using scanning transmission electron microscopy. An aberration-corrected instrument combined images of atomic columns with chemical analysis to investigate gold particles and particles containing two metals. This combination helps distinguish changes in shape from changes in composition, which can look deceptively similar in a single projection.^[ref]

A physicist who compiled X-ray wavelengths for precision spectroscopy. His 1967 compilation tabulates characteristic lines from elements including iron and molybdenum. Such reference wavelengths connect an observed diffraction angle to a crystal spacing through Bragg's law, and let a measured line be compared with an established atomic transition.^[ref]

Gordon I. Ogilvie develops the fluid dynamics of astrophysical systems. His lecture notes connect conservation laws, rotation and magnetic fields with simplified models of stars and disks, while his accretion-disk teaching shows how boundary conditions constrain steady transport.^[ref][ref]

A local stress prescription alone does not fix an entire disk solution: the mass supply, angular-momentum flux and conditions at its boundaries must be specified as well.

An experimental condensed matter physicist who coauthored an early phase-sensitive test of the pairing state in a cuprate superconductor. Interference in devices joining the cuprate to lead tested a relative phase shift predicted by d-wave superconductivity. The original report discusses device asymmetry and trapped vortices, showing why several observations must be assessed together when inferring the pairing symmetry.^[ref]

An experimental condensed matter physicist who coauthored a phase-sensitive test of d-wave superconductivity using a tricrystal ring. A ring containing three grain-boundary Josephson junctions exhibited spontaneous half-quantum magnetic flux, while two-junction control rings did not. The geometry converts a sign change of the pairing order parameter into a measurable magnetic signal.^[ref]

A theoretical condensed matter physicist who derived the Ginzburg-Landau theory of superconductivity from microscopic BCS theory near the transition temperature. His 1959 analysis identifies why the effective field couples with twice the charge of an electron: it describes Cooper pairs. This connects a useful macroscopic order parameter theory with the microscopic pairing mechanism and fixes its regime of validity.^[ref]

Elephter Andronikashvili tested the two-fluid model of superfluidity by oscillating a stack of closely spaced disks in liquid helium-4. Viscous coupling makes the normal component follow the disks, adding to their effective moment of inertia; the superfluid component need not rotate with them. Measuring the oscillation period as temperature changes therefore estimates the normal-fluid fraction under the apparatus's entrainment conditions. The experiment turns an apparently unusual flow law into a mechanical measurement of two distinct contributions to one liquid.^[ref]

An experimental atomic physicist who coauthored a test of dissipation in a Bose-Einstein condensate. A blue-detuned laser beam acted as a moving obstacle inside the gas. Strong heating appeared only above a critical speed, making motion of a controlled perturbation a probe of superfluidity and its breakdown.^[ref]

Hartland Snyder and J. Robert Oppenheimer calculated the gravitational collapse of an idealized, spherical, pressureless star. The Oppenheimer-Snyder model connects a comoving dust interior with a vacuum exterior and follows contraction beyond the limits of a static stellar model.^[ref]

The example separates a finite proper-time history of falling matter from the distant-coordinate description of increasingly redshifted light. Its neglected pressure and ideal symmetry make the mechanism tractable, while limiting its use as a detailed model of a real explosion.

An experimental physicist who coauthored evidence for the polymer brush regime in grafted chains. The collaboration used small-angle neutron scattering on polydimethylsiloxane attached by one end to silicon dioxide. Layer thickness changed with grafting density and solvent quality, showing how neighboring chains force one another to stretch away from a surface.^[ref]

Author of Lectures on Landau Theory of Phase Transitions by Peter D. Olmsted, whose title page identifies the Department of Physics, Georgetown University, and the date 9 July 2015.

A theoretical physicist who coauthored the 1997 paper introducing concurrence with William Wootters. The calculation uses a specially phased Bell basis to connect the coefficients of a two-qubit quantum state to its quantum entanglement. It provided an exact result for a class of mixed states, making entanglement quantification more concrete than a qualitative claim that two systems are correlated.^[ref]

A theoretical condensed matter physicist who coauthored the Schrieffer-Wolff transformation with John Robert Schrieffer. Their canonical transformation relates a model with fluctuating impurity charge to an effective model of spin exchange in the weak-mixing limit. This explains how virtual charge processes can produce the low-energy physics associated with the Kondo effect.^[ref]

A theoretical physicist who identified electron-phonon interaction as a promising basis for understanding superconductivity. In 1950, his independent theoretical proposal and the experimental superconducting isotope effect directed attention to lattice vibrations as part of the mechanism. This helped explain why understanding electron motion alone was insufficient: the response of the surrounding crystal also affects electronic behavior.^[ref]

Lead author of the 1996 transport study resolving shell filling and spin effects in few-electron vertical quantum dots.

Author of the 1962 proof of a spin-density-wave instability of the paramagnetic Hartree-Fock electron gas.

A computational physicist who coauthored a Quantum Monte Carlo calculation of the interacting electron gas with B. J. Alder. The method samples a many-particle quantum problem stochastically to obtain ground state correlation energies. Comparing candidate phases turns a microscopic interaction law into predictions about collective states, and gives other many-electron approximations a quantitative reference.^[ref]

A computational physicist who, with D. M. Ceperley, calculated electron-gas correlation energies using Quantum Monte Carlo in 1980. Their stochastic treatment of the Schrödinger equation compared competing fluid and crystalline states. Such calculations provide benchmarks for approximate treatments of interacting electrons, where exchange and correlation make an independent-particle description insufficient.^[ref]

John McGreevy develops quantum field theory through connections with many-particle physics. His authored lectures construct coherent-state path integrals for both bosons and fermions, relating the choice of integration variables to their different quantum statistics. The same treatment derives low-energy phase dynamics for a superfluid. This gives a concrete route from microscopic quantum degrees of freedom to a collective field description, explaining why similar field-theory methods recur in particle and condensed-matter physics.^[ref]

Author of Physics 215C: Quantum Field Theory, Part 3 by John McGreevy. Course record: mcgreevy.physics.ucsd.edu/s22/lecture-notes.html