Q_4_00 — Physics Methods: Subfolder Summary

Q_2_20 — Black Hole Information Paradox & Hawking Radiation

The black hole information paradox is arguably the deepest unsolved problem in theoretical physics, lying at the intersection of general relativity, quantum mechanics, and thermodynamics. In 1974, Stephen Hawking showed

Q_0_00 — Cosmology & Astrophysics: Section Summary

ZD_1_00 — Foundations Theory: Subfolder Summary

ZD_0_00 — Information & Computation: Section Summary

ZD_4_00 — Applied Interdisciplinary: Subfolder Summary

S_5_00 — Society Infrastructure: Subfolder Summary

ZA_2_00 — Gravity Spacetime Cosmology: Subfolder Summary

ZA_2_14 — Penrose Twistor Theory: Spinor Geometry and Spacetime

Twistor theory — conceived by Roger Penrose beginning in 1967 — is a radical reformulation of the geometry underlying physics in which the fundamental objects are not points in spacetime but rather twistors: elements of

ZA_5_03 — Infrasound — Physics, Biological Effects, and Anomalous Phenomena

Infrasound — sound below the conventional human hearing threshold of ~20 Hz — is a pervasive physical phenomenon generated by natural sources (wind, ocean waves, volcanic eruptions, earthquakes, thunderstorms, animal voc

ZA_5_19 — Bekenstein Bound: Information Limits and the Physics of Black Holes

The Bekenstein bound — proposed by Jacob Bekenstein in 1981 — establishes a fundamental upper limit on the amount of information (entropy) that can be contained within a given region of space with a given amount of energ

ZA_5_22 — Ionizing Radiation: Physics, Biological Effects, and Applications

Ionizing radiation — electromagnetic waves or particles with sufficient energy (>10 eV) to remove electrons from atoms — was discovered in the final years of the 19th century through a rapid sequence of breakthroughs: Wi

ZA_4_15 — Condensed Matter Physics: Emergent Phenomena in Many-Body Systems

Condensed matter physics — the largest subfield of physics by number of active researchers — studies the collective behavior of vast numbers of interacting particles (electrons, atoms, ions, spins) in solid, liquid, and

ZA_4_00 — Condensed Matter Thermodynamics: Subfolder Summary

ZA_4_22 — Superconductivity: BCS Theory to High-Temperature

Superconductivity — the complete vanishing of electrical resistance and the expulsion of magnetic fields below a critical temperature — was discovered by Heike Kamerlingh Onnes on April 8, 1911, in mercury at 4.2 K. The

ZA_4_11 — Time Crystals and Discrete Time Symmetry Breaking

A time crystal is a phase of matter that spontaneously breaks time-translation symmetry — the fundamental physical principle that the laws of physics are the same at all times (which, via Noether's theorem, is linked to

ZA_3_10 — Muon Anomalous Magnetic Moment

The anomalous magnetic moment of the muon ($a_\mu = (g-2)/2$) is one of the most precisely measured quantities in particle physics and one of the most sensitive probes for physics beyond the Standard Model. Every charged

ZA_3_13 — Higgs Boson: The Origin of Mass and the Standard Model's Final Piece

The Higgs boson — discovered on July 4, 2012, by the ATLAS and CMS experiments at CERN's Large Hadron Collider (LHC) — is the quantum excitation of the Higgs field, a scalar field that permeates all of space and gives ma

ZA_3_12 — Lattice Gauge Theory and Non-Perturbative QCD

Lattice gauge theory — the formulation of quantum field theories on a discrete spacetime lattice rather than in continuous spacetime — is the only known first-principles method for making non-perturbative calculations in

ZA_3_18 — Quark-Gluon Plasma and Exotic Matter States

Quark-gluon plasma (QGP) — a deconfined state of matter in which quarks and gluons, normally bound inside protons and neutrons by the strong nuclear force (quantum chromodynamics, QCD), roam freely over extended volumes