FIRST PRINTINGS OF THE FOUNDATIONAL PAPERS ON THE BIG BANG AND THE ORIGIN OF THE UNIVERSE. Including a fine copy of the famous “Alpha-Beta-Gamma” paper. More about The Origin of Chemical Elements. WITH: Expanding Universe and the Origin of Elements. WITH:...

FIRST EDITION, OFFPRINT, of Bohr's 1915 paper identifying conclusive experimental evidence for his model of the atom. More about On the Quantum Theory of Radiation and the Structure of the Atom

FIRST EDITION of Bohr, Kramers, and Clarke’s influential paper that “contained drastic theoretical proposals concerning the interaction of light and matter." Printed simultaneously in German in Zeitschrift fur Physik. More about The Quantum Theory of Radiation

FIRST EDITION IN ORIGINAL WRAPPERS OF BORN’S NEW MATHEMATICAL DESCRIPTION OF QUANTUM PHYSICS, INCLUDING THE FIRST USE OF THE TERM "QUANTUM MECHANICS." More about Über Quantenmechanik [On Quantum Mechanics

FIRST EDITION IN ORIGINAL WRAPPERS of the presentation of "Bose-Einstein statistics." More about Plancks Gesetz und Lichtquantenhypothese [Planck’s Law and Light Quantum Hypothesis]. WITH:...

FIRST EDITION IN ORIGINAL WRAPPERS of Compton’s report providing the data and experimental evidence for the dual wave-particle nature of electromagnetic radiation, later called “the Compton effect”. More about Secondary Radiations Produced by X-Rays

FIRST EDITION IN ORIGINAL WRAPPERS of Debye’s explanation of the dual wave-particle nature of electromagnetic radiation (the “Compton effect”). Precedes the full account by Compton. More about Zerstreuung von Röntgenstrahlen und Quantentheorie

AN EXTRAORDINARY LETTER BY EINSTEIN TO HIS SON OFFERING LIFE ADVICE AND DISCUSSING FREUD, SHAKESPEARE, AND SCHILLER. More about Autograph Letter Signed

FEYNMAN OFFERS ADVICE AND ENCOURAGEMENT FOR A SCIENTIFIC ENDEAVOR. More about Autograph Letter Signed [ALS

First edition, first printing, of Feynman's path integral formalism, his revolutionary approach to solving the fundamental equations of quantum mechanics and the basis for his later famous formulations of "Feynman rules" and "Feynman diagrams" More about Space-Time Approach to Non-Relativistic Quantum Mechanics

HEISENBERG PROVIDES HIS RECOLLECTIONS OF THE ORIGINS OF NIELS BOHR’S CONCEPT OF “COMPLEMENTARITY”. A UNIQUE ITEM, OF UTMOST IMPORTANCE FOR THE LIGHT IT SHEDS ON THE PHILOSOPHICAL FOUNDATIONS OF QUANTUM MECHANICS AS SEEN BY THE PIONEERS IN THE FIELD. More about Typed Letter Signed [TLS]. WITH: Photogravure Signed

FIRST EDITION in original wrappers of Lee and Yang's groundbreaking proposal to determine the nature of parity in weak interactions; essential to the modern understanding of elementary particles. More about Question of Parity Conservation in Weak Interactions

FIRST EDITION IN ORIGINAL WRAPPERS of the account of Millikan’s famous experiment, later known as the ‘oil-drop experiment’, in which he first provided the definitive proof that all electrical charges are exact multiples of a definite, fundamental value—the charge of the electron. More about A New Modification of the Cloud Method of Determining the Elementary Electrical Charge and the...