Penetrating Radiation at the Surface of and in Water

Penetrating Radiation on the Sea

Peter Bergmann and the invention of constrained Hamiltonian dynamics

Phenomenological and ontological models in natural science

Philosophical problems of space-time theories

Philosophy and Relativity

Philosophy Enters the Optics Laboratory: Bell's Theorem and its First Experimental Tests (1965-1982)

Physical Framework of Quantization Problem

Physicists and the 1945 Decision to Drop the Bomb

Physics and Five Problems in the Philosophy of Mind

Pioneer Women in Chaos Theory

Planck's blackbody radiation law: Presentation in different domains and determination of the related dimensional constants

Plasma: the genesis of the word

Poincare and relativity: the logic of the 1905 Palermo Memoir

Poincare and Special Relativity

Polygonal walls and the astronomical alignments of the Acropolis of Alatri, Italy: a preliminary investigation

Possible astronomical references in the planning of the Great Hopewell Road

Preludes to dark energy: Zero-point energy and vacuum speculations

Pressure and Motion of Dry Sand -- Translation of Hagen's Paper from 1852

Principles of the motion of fluids