| radial equation |
| radiation (defined in Atomic and nuclear structure) |
| Radiation at Thermodynamic Equilibrium. Kirchoff's Law. Black Radiation |
| radioactive decay (defined in Atomic and nuclear structure) |
| radioactivity (defined in Atomic and nuclear structure) |
| radioactivity (defined in Atomic and nuclear structure) |
| radiological and nuclear engineering (defined in automata theory and computer simulation applications to biomedicine) |
| radiopharmaceuticals (defined in Atomic and nuclear structure) |
| radius vector (=position vector) |
| Radon measure (defined in $\sigma$-finite Borel and Radon measures) |
| Radon measure (defined in probability distribution functions in physics) |
| Radon--Nikodym derivative (defined in probability distribution functions in physics) |
| R-algebroid |
| Raman (defined in spectroscopy topics) |
| random variable (defined in probability distribution functions in physics) |
| Rayleigh-Ritz method |
| R-category |
| R-diagram (defined in R-supercategory) |
| real exponential function (defined in growth of exponential function) |
| recursive function (defined in program) |
| Recursive Function |
| reduced quark mass (defined in gluons, quarks and QCD) |
| reducible representation (defined in superfields) |
| reference frame (defined in Axioms of Physics) |
| reference frame (defined in Fundamental physical concepts) |
| reference frames in newtonian physics |
| references for algebraic topology (= algebraic topology and category theory, bibliography of) |
| reference systems (defined in ballistics (2D)) |
| reflection (defined in spectroscopy topics) |
| reflection coefficient (defined in spectroscopy topics) |
| reflection properties (defined in Table of categories and functor properties) |
| refraction (defined in spectroscopy topics) |
| refraction coefficients (defined in spectroscopy topics) |
| regular (defined in Table of categories and functor properties) |
| regular measure |
| relation (defined in relation theory) |
| relational biology (defined in abstract relational biology (ARB)) |
| relational flag (defined in relation theory) |
| Relational Theories (=abstract relational biology (ARB)) |
| relation between force and potential energy |
| relation theory |
| relative Hurewicz theorem (defined in non-Abelian algebraic topology) |
| relative motion (defined in ballistics (2D)) |
| relativistic mass (defined in gluons, quarks and QCD) |
| relativistic phase velocities (defined in non-linear electron excitation of plasma waves) |
| relativistic total energy (defined in relativistic total energy) |
| relativistic total energy |
| Relativity: The Special and General Theory |
| relaxometry (defined in nuclear magnetic resonance principles) |
| representable functor (defined in categorical algebra) |
| representation of a Cc(G)*- topological algebra |
| representation of Banach *-algebras (defined in Quantum operator algebras in QFT) |
| representation of groupoids (=groupoid and group representations) |
| representation of locally compact groupoids |
| representation of the canonical commutation relations (defined in canonical commutation and anti-commutation relations: their representations) |
| $*$--representation on a Hilbert space (defined in weak Hopf C*-algebra) |
| representations (defined in algebraic categories and representations of classes of algebras) |
| representations of 4-D spaces |
| Representations of canonical anti-commutation relations (CAR) |
| representations of groupoids induced by measure |
| representation theory of canonical commutation relations (=CCR representation theory) |
| resistance (defined in conduction) |
| resistors in parallel |
| resistors in series |
| resonance |
| resonance (defined in Feynman's Lectures on Physics) |
| resonance frequency (defined in resonance) |
| resonance frequency (defined in nuclear magnetic resonance principles) |
| resonance phenomenon (defined in nuclear magnetic resonance principles) |
| resonant system (defined in resonance) |
| resonant two-body system (defined in Efimov states) |
| restriction map (defined in Functorial Algebraic Geometry and Physics) |
| retraction (defined in isomorphism) |
| reversible process (defined in principles of thermodynamics) |
| reversible process (defined in principles of thermodynamics) |
| Reynolds' transport theorem |
| rf perturbation (defined in nuclear magnetic resonance principles) |
| rf pulse (defined in nuclear magnetic resonance principles) |
| rf quantum (defined in nuclear magnetic resonance principles) |
| R-heterofunctor (defined in R-supercategory) |
| rho (defined in notations of fundamental concepts in physics) |
| \rho (defined in notations of fundamental concepts in physics) |
| ribosomes (defined in George Palade) |
| Riccati equation (defined in time-dependent harmonic oscillators) |
| Riccati equation |
| Riccati solutions (defined in Riccati equation) |
| Ricci flow (defined in geometrization conjecture and theorem) |
| Ricci gradient flow (defined in geometrization conjecture and theorem) |
| Riemannian geometry (defined in quantum Riemannian geometry) |
| Riemannian metric tensor (defined in representations of 4-D spaces) |
| Riemann surface |
| Riemann zeta function |
| rigged Hilbert space |
| right adjoint functor (=section functor) |
| rigid body |
| rigid body (defined in center of mass) |
| rigid monoidal category (defined in quantum categories) |
| ringoid (defined in R-algebroid) |
| ring with n-objects (defined in R-module) |
| RIXS (defined in magnons) |
| R-module |
| R-module (defined in R-module) |
| Robert Rosen |
| robot (=computer) |
| Roentgen's Ray |
| Ronald Brown |
| Rotational Inertia (=moment of inertia) |
| rotational inertia of a circular disk (=moment of inertia of a circular disk) |
| Rotational Inertia of a Solid Cylinder |
| rotational inertia of a solid sphere |
| rotational kinetic energy (defined in kinetic energy) |
| rotational spectroscopy (defined in Vibrational and Rotational Spectroscopy) |
| rough ER (defined in George Palade) |
| R-supercategory |
| R)-systems (defined in abstract relational biology (ARB)) |
| R)-systems (=abstract relational biology (ARB)) |
| R)-systems category (defined in abstract relational biology (ARB)) |
| $R[X_1,..., X_r]$ (defined in Nicolae Popescu) |