B Mesons --- Bc Mesons --- Background Field Methods --- Background Radiation --- Bag Model --- Ball Lightning --- Barkhausen Effect ---- Barnett Effect --- Barred Galaxies --- Baryogenesis --- Baryonic Dark Matter --- Baryons --- Bayesian Statistics --- BCS Theory --- Bell's Theorem --- Berry's Phases --- Beta Decay --- Bethe, Hans --- Bethe Ansatz --- Bethe Cycle --- Bethe-Salpeter Formalism --- Beyond the Standard Model --- BFKL Equation --- Bhabha Scattering --- Big Bang --- Big Bang Nucleosynthesis --- Bileptons --- Binary Fluids --- Binary Stars --- Bioastronomy --- Biological Networks -- Biophysics --- Biopolymers --- Bipolar Flows --- Birefringence --- Blackbody Radiation --- Black Holes --- Blazars --- BL Lac Objects --- Bloch Oscillations --- Blue Supergiants --- Bohm-Aharonov Effect --- Bohm-de Broglie Theory --- Bohr Atom --- Bolides --- Born-Infeld Theory --- Born-Oppenheimer Approximation --- Bose Condensates --- Bosonization --- Bosons --- Boson Stars --- Bottom Quark --- Bottomonia --- Braids --- Branching Processes --- Brane Cosmology --- Branes --- Breathers --- Bremsstrahlung --- Bronze --- Brown Dwarfs --- Brownian Motion --- Burger's Vector