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Enrique Galvez develops optical experiments and teaching methods in quantum mechanics. With collaborators, he explained photon transformations at a beam splitter using probability amplitudes rather than only classical intensities. A consistent unitary matrix keeps the reflection and transmission wave phases together, so different paths can interfere correctly. This connects a familiar laboratory component with the quantum accounting needed to predict detection probabilities.^[ref]

A physicist.^[ref]

An experimental physicist whose cryogenic expertise contributed to the Wu experiment. The National Bureau of Standards laboratory could align atomic nuclei at extremely low temperature, enabling a directional beta decay test in cobalt-60. The collaboration demonstrated a failure of parity conservation.^[ref]

Ernest Lawrence and M. Stanley Livingston developed repeated acceleration of ions in a cyclotron. An oscillating electric field accelerates a particle each time it crosses the gap between two hollow electrodes; a perpendicular magnetic field bends it back toward the gap. In the nonrelativistic approximation, the orbit period $2\pi m/(|q|B)$ is independent of radius, allowing successive crossings to stay synchronized. Their 1932 report obtained proton energies of $1.22\mathrm{MeV}$ with a maximum applied voltage of $4,000\mathrm{V}$.^[ref]

A physicist.^[ref]

Ernest Marsden and Hans Geiger observed alpha particles scattered through large angles by metal targets. Counting weak scintillations supplied an event-based readout even when only a small fraction of the incident beam returned toward its source. The observation challenged descriptions that attributed all deflections to many weak encounters. Their later measurements varied geometry and target conditions to test the single-scattering interpretation behind Rutherford scattering.^[ref]

A physicist.^[ref]

Ernest Rutherford's 1911 calculation explained rare large-angle alpha particle scattering by concentrating an atom's central electric charge into a region small compared with the atom. In the single-Rutherford scattering approximation, the predicted differential scattering cross-section varies as ${\sin }^{-4}(\theta /2)$ and as the inverse square of the incident kinetic energy. These dependencies make the model testable through angular counts and controlled changes of beam energy, beyond merely observing that occasional particles turn backward.^[ref]

A physicist.^[ref]

The Rutherford scattering model connects large-angle deflections to concentrated electric charge. The Geiger-Marsden experiment supplies the experimental context; a predicted angular distribution needs comparison with detector geometry and background counts.

Ernest Walton and John Cockcroft produced nuclear reactions with a controlled beam of electrically accelerated protons. Their 1932 lithium experiment detected energetic alpha particles from the target. The apparatus made both the incident proton energy and the outgoing reaction products experimentally accessible, replacing reliance on naturally emitted projectiles alone. The result demonstrated how accelerator control could be used to investigate the binding and transformation of atomic nuclei.^[ref]

A physicist.^[ref][ref]

A physicist.^[ref]

The early two-stage electron microscope experiment investigates how magnetic electron lenses can form a magnified image. The electron microscope article distinguishes magnification from electron microscope resolution.

Erwin Hahn discovered spin echo signals, in which radiofrequency pulses restore an observable signal from nuclear spins that have apparently lost phase coherence. A spread of static magnetic fields makes different spins precess at different rates; suitable later pulses allow this reversible dephasing to refocus. The echo amplitude then probes relaxation and diffusion, rather than being determined solely by static field inhomogeneity. His 1950 analysis made pulsed nuclear magnetic resonance a method for distinguishing different causes of signal decay.^[ref]

A physicist who developed spin echo methods and studied nuclear magnetic resonance and optics.^[ref]

A theoretical physicist who reformulated the single-electron Schrödinger equation as hydrodynamic equations, now called the Madelung equations. Writing the wave function in terms of magnitude and phase connects its evolution with a density and a flow. The formulation makes a useful bridge between quantum-wave dynamics and fluid descriptions while retaining an additional quantum contribution to the force balance.^[ref]

A physicist who developed wave mechanics. In 1926, Erwin Schrödinger made the energies of chemical atoms an eigenvalue problem, rather than prescribing a separate quantization rule for each classical orbit. He shared the Nobel Prize in Physics in 1933 with Paul Dirac.^[ref]

The Schrödinger equation turns a proposed Hamiltonian operator into predictions for a wavefunction and its evolution. Boundary conditions can select discrete energy eigenvalues, while quantum superposition makes their relative quantum phases observable through interference. The infinite square well gives a transparent worked example; a hydrogen atom supplies a physical application with a different potential energy.

The Davisson–Germer experiment gives a complementary experimental route into matter waves: an accelerated electron beam scattered from a nickel crystal produces direction-dependent collected electric current. Its apparatus and angular scans make the wave prediction testable. Interpreting a wavefunction as a probability amplitude also requires the Born rule; that statistical interpretation deserves its own history alongside Erwin Schrödinger's dynamics.

Eugene Wigner and Gregory Breit connected the capture of slow neutrons with resonant excited states of a target atomic nucleus. A capture probability can change rapidly when the projectile energy crosses one of these states. Their treatment relates the peak to the coupling into the intermediate state and its possible decay channels. It therefore explains why a small interval of incident energies can contain pronounced structure, rather than a smooth response determined by the target's size alone.^[ref]

A physicist.^[ref]

Evangelista Torricelli interpreted the support of a Mercury column in terms of external atmospheric pressure. His 11 June 1644 letter to Michelangelo Ricci describes equal column heights in vessels with different upper spaces, testing whether the support came from outside the vessel. In modern hydrostatic pressure notation, $p_{\mathrm{atm}}-p_{\mathrm{top}}=\rho gh$, where $\rho$ is the liquid's density and $g$ is gravitational acceleration. When the upper pressure is small, the column height measures atmospheric pressure, as in a barometer. Comparing liquids of different densities explains why water requires a much taller column than Mercury.^[ref]

A physicist and mathematician associated here with Torricelli's law.^[ref]

A physicist whose teaching connects microscopic scattering with electrical transport in metals. His derivation of the Drude model averages over electrons that have and have not collided during a short time interval. The resulting equation balances the driving electric force against relaxation of mean momentum, explaining why a steady electric current can flow without indefinite acceleration. The calculation identifies the relaxation time as the link between individual scattering events and bulk electrical conductivity.^[ref]

Felix Bloch developed the nuclear-induction description of nuclear magnetic resonance. A precessing transverse magnetization generates an oscillating magnetic flux and therefore a voltage in a surrounding coil. The signal provides direct access to the collective motion of nuclear magnetic moments. His equations include both precession in the applied magnetic field and relaxation toward equilibrium, connecting the coherent nuclear motion with the decay and recovery measured in an experiment.^[ref]

A physicist.^[ref]

Ferenc Krausz coauthored a 2001 demonstration of attosecond timing using photoionization. A synchronized visible electric field changes the energy distribution of photoelectrons released by a soft-X-ray optical pulse. Scanning their relative delay converts an otherwise inaccessible time interval into a measured electron spectrum. The report inferred a soft-X-ray duration of $650\pm 150$ attoseconds and demonstrated an instrument for probing electron dynamics on that scale.^[ref]

A physicist who leads research in attosecond physics.^[ref]

An experimental physicist who coauthored a gravitational constant measurement with cold atoms. The apparatus compared two spatially separated atom interferometers, helping distinguish the source-mass signal from common disturbances.^[ref]

Identity: arxiv.org/abs/1003.1481

Institutional profile: www.difi.unige.it/it/dipartimento/persone/fiodor-sorrentino

An experimental physicist who studied electrical injection of electron spin and spin accumulation in lateral metallic devices. A separate detector measured the spin signal away from the main charge-current path, suppressing ordinary magnetoresistance backgrounds. Comparing electrode materials and measuring at low and room temperature made the apparatus a test of how far spin information survives in a metal.^[ref]

A physicist working on biological imaging and optical manipulation. His LENS research includes spectroscopy and imaging of biological tissue, linking the development of optical instruments to measurements of living systems.^[ref]

He coauthored the 2006 calibration study of optical tweezers, testing how a known stage motion can provide an absolute scale for a bead-position signal.^[ref]

Francis Halzen initiated IceCube, using a large volume of Antarctic ice as a medium for neutrino detection. Optical modules record Cherenkov radiation from secondary charged particles. Their arrival times and detected light allow reconstruction of a particle's direction and deposited energy. Because atmospheric particles also produce signals, identifying cosmic neutrinos requires event selection and explicit background estimates. The instrument connects high-energy particle with observations of distant astrophysical sources.^[ref]

A physicist who initiated IceCube and researched particle, astrophysics and cosmology.^[ref]

An experimental physicist who contributed to the 1962 rocket experiment reported with Riccardo Giacconi, Herbert Gursky and Bruno Benedetto Rossi. The payload used large-area Geiger counters with thin mica windows to detect soft X-rays; surrounding scintillation counters rejected charged-particle background. As the rocket rotated, the detectors scanned the sky and found a strong directional excess. The result supplied early evidence for X-ray sources outside the Solar system.^[ref]