Other Free Encyclopedias » Science Encyclopedia » Science & Philosophy: Philosophy of Mind - Early Ideas to Planck length » Physics - Middle Ages, Sixteenth And Seventeenth Centuries, Eighteenth Century, Nineteenth Century, Causes Of Motion: Medieval Understandings

Physics - End Of Classical Physics

press university york cambridge

By the close of the nineteenth century, many physicists felt that the accomplishments of the century had produced a mature and relatively complete science. Nevertheless, a number of problem areas were apparent to at least some of the community, four of which are closely related to developments mentioned above.

New rays and radiations were discovered near the end of the century, which helped establish (among other things) the modern model of the atom. These included the discovery (by William Crookes and others) of cathode rays within discharge tubes; Wilhelm Conrad Röntgen's finding, in 1895, of X rays emanating from discharge tubes; and Antoine-Henri Becquerel's discovery in 1896 that uranium salts were "radioactive" (as Marie Curie labeled the effect in 1898). Each of these led to further developments. In 1897, Joseph John Thomson identified the cathode rays as negatively charged particles called "electrons" and, a year later, was able to measure the charge directly. In 1898, Ernest Rutherford identified two different kinds of radiation from uranium, calling them alpha and beta. In 1902 and 1903, he and Frederick Soddy demonstrated that radioactive decay was due to the disintegration of heavy elements into slightly lighter elements. In 1911, he scattered alpha particles from thin gold foils and explained infrequent scattering to large angles by the presence of a concentrated, positively charged atomic nucleus.

The study of blackbody radiation (radiation from a heated object that is a good emitter) yielded results that are crucial to the early development of quantum mechanics. In 1893 Wilhelm Wien derived a promising "displacement law" that gave the wavelength at which a blackbody radiated at maximum intensity, but precision data failed to confirm it. Furthermore, classical theory proved unable to model the intensity curves, especially at lower wavelengths. In 1900 the German theoretical physicist Max Planck (1858–1947) derived the intensity curve using the statistical methods of the Austrian physicist Ludwig Eduard Boltzmann (1844–1906) and the device of counting the energy of the oscillators of the blackbody in increments of hf, where f is the frequency and h is a constant (now known as "Planck's constant"). Despite achieving excellent fits to data, Planck was hesitant to accept his own derivation, due to his aversion for statistical methods and atomism.

It is doubtful that Planck interpreted his use of energy increments to mean that the energy of the oscillators and radiation came in chunks (or "quanta"). However, this idea was clearly enunciated by Albert Einstein in his 1905 paper on the photoelectric effect. Einstein explained in this paper why the electrons that are ejected from a cathode by incident light do not increase in energy when the intensity of the light is increased. Instead, the fact that the electrons increase in energy when the frequency of the light is increased suggested that light comes in quantum units (later called "photons") and have an energy given by Planck's equation, hf.

Electromagnetic theory, though one of the most important results of nineteenth-century physical theory, contained a number of puzzles. On the one hand, electromagnetism sometimes gave the same result for all reference frames. For example, Faraday's induction law gave the same result for the current induced in a loop of wire for two situations: when the loop moves relative to a stationary magnet and when the magnet moves (with the same speed) relative to a stationary loop. On the other hand, if an ether medium were introduced for electromagnetic waves, then the predictions of electromagnetism should usually change for different reference frames. In a second paper from 1905, Einstein reinterpreted attempts by Henri Poincaré (1854–1912) and Hendrik Antoon Lorentz (1853–1928) to answer this puzzle, by insisting that the laws of physics should give the same results in all inertial reference frames. This, along with the principle of the constancy of the speed of light, formed the basis of Einstein's special theory of relativity.

See also Causality; Change; Chemistry; Experiment; Field Theories; Mathematics; Mechanical Philosophy; Quantum; Relativity; Science.



Brush, Stephen G. The Kinetic Theory of Gases: An Anthology of Classic Papers with Historical Commentary. Edited by Nancy S. Hall. London: Imperial College Press, 2003.

Franklin, Benjamin, Benjamin Franklin's Experiments: A New Edition of Franklin's Experiments and Observations on Electricity. Edited by I. Bernard Cohen. Cambridge, Mass.: Harvard University Press, 1941.

Galilei, Galileo. Two New Sciences: Including Centers of Gravity and Force of Percussion. Translated by Stillman Drake. Madison: University of Wisconsin Press, 1974.

Newton, Isaac. Opticks; or, a Treatise of the Reflections, Refractions, Inflections, and Colours of Light. Based on the 4th ed., London 1730. New York: Dover, 1952.

——. The Principia: Mathematical Principles of Natural Philosophy. Translated by I. B. Cohen and Anne Whitman. Berkeley: University of California Press, 1999.

Maxwell, James Clerk. A Treatise on Electricity and Magnetism. 2 vols. Unabridged 3rd ed. New York: Oxford University Press, 1998.

Shamos, Morris H., ed. Great Experiments in Physics. 1959. Reprint, New York: Dover, 1987. Features brief introductions to each experiment, followed by passages from the original publications.


Berry, Arthur. A Short History of Astronomy: From Earliest Times through the Nineteenth Century. New York: Dover, 1961.

Brush, Stephen G. Statistical Physics and the Atomic Theory of Matter: From Boyle and Newton to Landau and Onsager. Princeton, N.J.: Princeton University Press, 1983.

Buchwald, Jed Z. The Creation of Scientific Effects: Heinrich Hertz and Electric Waves. Chicago: University of Chicago Press, 1994. A detailed account for the advanced reader.

——. The Rise of the Wave Theory of Light: Optical Theory and Experiment in the Early Nineteenth Century. Chicago: University of Chicago Press, 1989.

Cahan, David. An Institute for an Empire: The Physikalisch-Technische Reichanstalt, 1871–1918. Cambridge, U.K., and New York: Cambridge University Press, 1989. An exemplary study of how physical science served state interests.

Caneva, Kenneth L. Robert Mayer and the Conservation of Energy. Princeton, N.J.: Princeton University Press, 1993.

Cannon, John T., and Sigalia Dostrovsky. The Evolution of Dynamics: Vibration Theory from 1687 to 1742. New York: Springer-Verlag, 1981. Detailed history for mathematically adept readers.

Cercignani, Carlo. Ludwig Boltzmann: The Man Who Trusted Atoms. New York: Clarendon, 1998.

Clagett, Marshall. The Science of Mechanics in the Middle Ages. Madison: University of Wisconsin Press, 1959.

Cohen, H. Floris. The Scientific Revolution: A Historiographical Inquiry. Chicago: University of Chicago Press, 1994. A long but valuable historiographic survey.

Cohen, I. Bernard. The Birth of a New Physics. Rev. ed. New York, W. W. Norton, 1985. An excellent place to start for the general reader, covering the period from Copernicus to Newton.

——. The Newtonian Revolution. Norwalk, Conn: Burndy Library, 1987.

D'Agostino, Salvo. A History of the Ideas of Theoretical Physics: Essays on the Nineteenth and Twentieth Century Physics. Boston: Kluwer, 2000.

Damerow, Peter, et al. Exploring the Limits of Preclassical Mechanics: A Study of Conceptual Development in Early Modern Science. New York: Springer-Verlag, 1992. Detailed treatments of the motion studies of Descartes, Galileo, and Beeckman.

Dear, Peter. Revolutionizing the Sciences: European Knowledge and Its Ambitions, 1500–1700. Princeton, N.J.: Princeton University Press, 2001.

Dobbs, Betty Jo Teeter, and Margaret C. Jacob. Newton and the Culture of Newtonianism. Atlantic Highlands, N.J.: Humanities Press, 1995.

Dugas, René. A History of Mechanics. Translated by J. R. Maddox. New York: Dover, 1988. A useful survey from ancient to modern times, concentrating on the development of theory and often using long quotations from the original sources.

Duhem, Pierre. Essays in History and Philosophy of Science. Edited by Roger Ariew and Peter Barker. Indianapolis: Hackett, 1996. Includes Duhem's excellent article on the history of physics, written for an encyclopedia.

——. Medieval Cosmology: Theories of Infinity, Place, Time, Void, and the Plurality of Worlds. Edited and translated by Roger Ariew. Chicago: University of Chicago Press, 1985.

Elkana, Yehuda. The Discovery of the Conservation of Energy. Cambridge, Mass.: Harvard University, 1974.

Fraser, Craig G. Calculus and Analytical Mechanics in the Age of Enlightenment. Aldershot, U.K., and Brookfield, Vt.: Variorum, 1997. Detailed history for mathematically adept readers.

Gillmor, C. Stewart. Coulomb and the Evolution of Physics and Engineering in Eighteenth-Century France. Princeton, N.J.: Princeton University Press, 1971.

Goldstine, Herman H. A History of the Calculus of Variations from the Seventeenth through the Nineteenth Century. New York: Springer-Verlag, 1980. Detailed history for mathematically adept readers.

Grant, Edward. The Foundations of Modern Science in the Middle Ages: Their Religious, Institutional, and Intellectual Contexts. Cambridge, U.K., and New York: Cambridge University Press, 1996. A good place to start for the general reader.

Hakfoort, Casper. Optics in the Age of Euler: Conceptions of the Nature of Light, 1700–1795. Cambridge, U.K., and New York: Cambridge University Press, 1995.

Hankins, Thomas L. Science and the Enlightenment. Cambridge, U.K., and New York: Cambridge University Press, 1985. The best place to start for the general reader.

Harman, P. M. Energy, Force, and Matter: The Conceptual Development of Nineteenth-Century Physics. Cambridge, U.K., and New York: Cambridge University Press, 1982. A useful book but compact and difficult for the beginner.

——. The Natural Philosophy of James Clerk Maxwell. Cambridge, U.K., and New York: Cambridge University Press, 1998.

Heilbron, J. L. Electricity in the Seventeenth and Eighteenth Centuries: A Study of Early Modern Physics. Berkeley: University of California Press, 1979. A particularly good survey of both the conceptual and the institutional development of physics.

Hendry, John. James Clerk Maxwell and the Theory of the Electromagnetic Field. Bristol, U.K., and Boston: A. Hilger, 1986. A superb scientific biography with a useful interpretive framework that has been used in the present essay.

Hogendijk, Jan P., and Abdelhamid I. Sabra, eds. The Enterprise of Science in Islam: New Perspectives. Cambridge: MIT Press, 2003.

Holton, Gerald, and Stephen G. Brush. Physics, the Human Adventure: From Copernicus to Einstein and Beyond. New Brunswick, N.J.: Rutgers University Press, 2001. A textbook for teaching physics with history.

Jungnickel, Christa, and Russell McCormmach. Cavendish: The Experimental Life. Rev. ed. Cranbury, N.J.: Bucknell University Press, 1999.

——. Intellectual Mastery of Nature: Theoretical Physics from Ohm to Einstein. Chicago: University of Chicago Press, 1986. A detailed study of the conceptual and institutional development of theoretical physics as a subdiscipline.

Kline, Morris. Mathematical Thought from Ancient to Modern Times. New York: Oxford University Press, 1972.

Kuhn, Thomas S. Black-body Theory and the Quantum Discontinuity, 1894–1912. Chicago: University of Chicago Press, 1987.

——. The Copernican Revolution: Planetary Astronomy in the Development of Western Thought. Cambridge, Mass.: Harvard University Press, 1971.

Leijenhorst, Cees, Christoph Luthy, Johannes M. M. H. Thigjssen, eds. The Dynamics of Aristotelian Natural Philosophy from Antiquity to the Seventeenth Century. Leiden, Netherlands: Brill, 2002.

Lindberg, David C. The Beginnings of Western Science: The European Scientific Tradition in Philosophical, Religious, and Institutional Context, 600 B.C. to A.D. 1450. Chicago: University of Chicago Press, 1992. A good place to start for the general reader.

Lindberg, David C., ed. Science in the Middle Ages. Chicago: University of Chicago Press, 1978.

Mach, Ernst. The Principles of Physical Optics: An Historical and Philosophical Treatment. Mineola, N.Y.: Dover, 2003.

——. Principles of the Theory of Heat: Historically and Critically Elucidated. Edited by Brian McGuinness. Boston: D. Reidel, 1986.

——. The Science of Mechanics: A Critical and Historical Account of Its Development. Translated by Thomas J. McCormack. 6th ed. LaSalle, Ill.: Open Court, 1960. Mach's books are guilty of "presentism," the tendency to judge past science in terms of current knowledge. Nevertheless, his work should be studied by the more advanced student.

Maier, Anneliese. On the Threshold of Exact Science: Selected Writings of Anneliese Maier on Late Medieval Natural Philosophy. Edited and translated by Steven D. Sargent. Philadelphia: University of Pennsylvania Press, 1982.

Merz, John Theodore. A History of European Thought in the Nineteenth Century. Vols. 1 and 2. New York: Dover, 1965. Reprint of edition appearing between 1904 and 1912.

Olesko, Kathryn M. Physics as a Calling: Discipline and Practice in the Konigsberg Seminar for Physics. Ithaca, N.Y.: Cornell University Press, 1991.

Park, David. The Fire Within the Eye: A Historical Essay on the Nature and Meaning of Light. Princeton, N.J.: Princeton University Press, 1997. A good popularization.

Pullman, Bernard. The Atom in the History of Human Thought. New York: Oxford University Press, 1998. Guilty of "presentism," but nevertheless a useful survey.

Purrington, Robert D. Physics in the Nineteenth Century. New Brunswick, N.J.: Rutgers University Press, 1997. The best place to start for the general reader.

Segrè, Emilio. From Falling Bodies to Radio Waves: Classical Physicists and Their Discoveries. New York: W. H. Freeman, 1984.

——. From X-Rays to Quarks: Modern Physicists and Their Discoveries. San Francisco: W. H. Freeman, 1980.

Stephenson, Bruce. Kepler's Physical Astronomy. New York: Springer-Verlag, 1987.

Tokaty, G.A. A History and Philosophy of Fluid Mechanics. 2nd ed. New York: Dover, 1994.

Toulmin, Stephen, and June Goodfield. The Architecture of Matter. Chicago: University of Chicago Press, 1982. A history of theories of matter, from ancient to modern times.

Truesdell, C., The Tragicomical History of Thermodynamics, 1822–1854. New York: Springer-Verlag, 1980. Detailed history for mathematically adept readers.

Westfall, Richard S. The Construction of Modern Science: Mechanisms and Mechanics. Cambridge, U.K., and New York: Cambridge University Press, 1977.

——. Force in Newton's Physics: The Science of Dynamics in the Seventeenth Century. New York: Elsevier, 1971.

——. Never at Rest: A Biography of Isaac Newton. Cambridge, U.K., and New York: Cambridge University Press, 1980.

Whittaker, Edmund. A History of the Theories of Aether and Electricity. New York: Humanities Press, 1973.

Williams, L. Pearce. The Origins of Field Theory. Lanham, Md.: University Press of America, 1980. This classic study focuses on the work of Michael Faraday.

G. J. Weisel

Physics - Bibliography [next] [back] Physics - Second Law Of Thermodynamics

User Comments

Your email address will be altered so spam harvesting bots can't read it easily.
Hide my email completely instead?

Cancel or