Richard C. Tolman

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Richard C. Tolman
Tolman & Einstein.jpg
Richard C. Tolman and Albert Einstein at Caltech, 1932.
Born(1881-03-04)March 4, 1881
West Newton, Massachusetts, U.S.
DiedSeptember 5, 1948(1948-09-05) (aged 67)
Pasadena, California, U.S.
Scientific career
Doctoral students Allan C. G. Mitchell

Richard Chace Tolman (March 4, 1881 – September 5, 1948) was an American mathematical physicist and physical chemist who was an authority on statistical mechanics. He also made important contributions to theoretical cosmology in the years soon after Einstein's discovery of general relativity. He was a professor of physical chemistry and mathematical physics at the California Institute of Technology (Caltech).

United States Federal republic in North America

The United States of America (USA), commonly known as the United States or America, is a country comprising 50 states, a federal district, five major self-governing territories, and various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is slightly smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U.S. is the third most populous country. The capital is Washington, D.C., and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico. The State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.

Mathematical physics Application of mathematical methods to problems in physics

Mathematical physics refers to the development of mathematical methods for application to problems in physics. The Journal of Mathematical Physics defines the field as "the application of mathematics to problems in physics and the development of mathematical methods suitable for such applications and for the formulation of physical theories". It is a branch of applied mathematics, but deals with physical problems.

Statistical mechanics is one of the pillars of modern physics. It is necessary for the fundamental study of any physical system that has a large number of degrees of freedom. The approach is based on statistical methods, probability theory and the microscopic physical laws.



Tolman in 1945 Richard C. Tolman 1945 2003 902 314 ng451h74s.tiff
Tolman in 1945

Tolman was born in West Newton, Massachusetts and studied chemical engineering at the Massachusetts Institute of Technology, receiving his bachelor's degree in 1903 and Ph.D. in 1910 under A. A. Noyes. [1]

West Newton, Massachusetts village of Newton, Massachusetts

West Newton is a village of the City of Newton, Massachusetts and is one of the oldest of the thirteen Newton villages. The West Newton Village Center is a National Register Historic District. The postal ("Zip") code 02465 roughly matches the village limits.

Chemical engineering branch of science that applies physical sciences and life sciences together with applied mathematics and economics to produce, transform, transport, and properly use chemicals, materials and energy

Chemical engineering is a branch of engineering that uses principles of chemistry, physics, mathematics, biology, and economics to efficiently use, produce, transform, and transport chemicals, materials, and energy. A chemical engineer designs large-scale processes that convert chemicals, raw materials, living cells, microorganisms, and energy into useful forms and products.

Massachusetts Institute of Technology University in Massachusetts

The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts. Founded in 1861 in response to the increasing industrialization of the United States, MIT adopted a European polytechnic university model and stressed laboratory instruction in applied science and engineering. It has since played a key role in the development of many aspects of modern science, engineering, and mathematics, and is widely known for its innovation and academic strength, making it one of the most prestigious institutions of higher learning in the world. The Institute is a land-grant, sea-grant, and space-grant university, with an urban campus that extends more than a mile alongside the Charles River.

He married Ruth Sherman Tolman in 1924.

In 1912, he conceived of the concept of relativistic mass by writing that "the expression m0(1 - v2/c2)−1/2 is best suited for the mass of a moving body." [2]

In a 1916 experiment with Thomas Dale Stewart, Tolman demonstrated that electricity consists of electrons flowing through a metallic conductor. A by-product of this experiment was a measured value of the mass of the electron. [3] Overall, however, he was primarily known as a theorist.

Thomas Dale Stewart was an American chemist.

Electricity Physical phenomena associated with the presence and flow of electric charge

Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. In early days, electricity was considered as being not related to magnetism. Later on, many experimental results and the development of Maxwell's equations indicated that both electricity and magnetism are from a single phenomenon: electromagnetism. Various common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others.

Electron subatomic particle with negative electric charge

The electron is a subatomic particle, symbol
, whose electric charge is negative one elementary charge. Electrons belong to the first generation of the lepton particle family, and are generally thought to be elementary particles because they have no known components or substructure. The electron has a mass that is approximately 1/1836 that of the proton. Quantum mechanical properties of the electron include an intrinsic angular momentum (spin) of a half-integer value, expressed in units of the reduced Planck constant, ħ. Being fermions, no two electrons can occupy the same quantum state, in accordance with the Pauli exclusion principle. Like all elementary particles, electrons exhibit properties of both particles and waves: they can collide with other particles and can be diffracted like light. The wave properties of electrons are easier to observe with experiments than those of other particles like neutrons and protons because electrons have a lower mass and hence a longer de Broglie wavelength for a given energy.

Tolman was a member of the Technical Alliance in 1919, a forerunner of the Technocracy movement where he helped conduct an energy survey analyzing the possibility of applying science to social and industrial affairs. [4] [5] [6]

Technical Alliance

The Technical Alliance was a group of engineers, scientists, and technicians based in New York City, formed towards the end of 1919 by American engineer Howard Scott. The Alliance started an Energy Survey of North America, aimed at documenting the wastefulness of the capitalist system.

Technocracy movement social movement

The technocracy movement is a social movement which arose in the early 20th century. Technocracy was popular in the United States and Canada for a brief period in the early 1930s, before it was overshadowed by other proposals for dealing with the crisis of the Great Depression. The technocracy movement proposed replacing politicians and businesspeople with scientists and engineers who had the technical expertise to manage the economy.

Tolman was elected a Fellow of the American Academy of Arts and Sciences in 1922. [7] The same year, he joined the faculty of the California Institute of Technology, where he became professor of physical chemistry and mathematical physics and later dean of the graduate school.

American Academy of Arts and Sciences United States honorary society and center for independent policy research

The American Academy of Arts and Sciences is one of the oldest learned societies in the United States. Founded in 1780, the Academy is dedicated to honoring excellence and leadership, working across disciplines and divides, and advancing the common good.

California Institute of Technology private research university located in Pasadena, California

The California Institute of Technology (Caltech) is a private doctorate-granting research university in Pasadena, California. Known for its strength in natural science and engineering, Caltech is often ranked as one of the world's top-ten universities.

One of Tolman's early students at Caltech was the theoretical chemist Linus Pauling, to whom Tolman taught pre-Schrödinger quantum theory.

In 1927, Tolman published a text on statistical mechanics whose background was the old quantum theory of Max Planck, Niels Bohr and Arnold Sommerfeld. [8] In 1938, he published a new detailed work that covered the application of statistical mechanics to classical and quantum systems. [9] [10] It was the standard work on the subject for many years and remains of interest today.

In the later years of his career, Tolman became increasingly interested in the application of thermodynamics to relativistic systems and cosmology. An important monograph he published in 1934 titled Relativity, Thermodynamics, and Cosmology [11] demonstrated how black body radiation in an expanding universe cools but remains thermal  a key pointer toward the properties of the cosmic microwave background. [12] Also in this monograph, Tolman was the first person to document and explain how a closed universe could equal zero energy. He explained how all mass energy is positive and all gravitational energy is negative and they cancel each other out, leading to a universe of zero energy. [12] His investigation of the oscillatory universe hypothesis, which Alexander Friedmann had proposed in 1922, drew attention to difficulties as regards entropy and resulted in its demise until the late 1960s.

During World War II, Tolman served as scientific advisor to General Leslie Groves on the Manhattan Project. At the time of his death in Pasadena, he was chief advisor to Bernard Baruch, the U.S. representative to the United Nations Atomic Energy Commission.

Each year, the southern California section of the American Chemical Society honors Tolman by awarding its Tolman Medal "in recognition of outstanding contributions to chemistry."


Tolman's brother was the behavioral psychologist Edward Chace Tolman.

See also

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  1. Richard C. Tolman at the Mathematics Genealogy Project
  2. Tolman, R. C. (1912). "Non-Newtonian Mechanics, The Mass of a Moving Body". Philosophical Magazine. 23: 375–381. doi:10.1080/14786440308637231.
  3. Tolman, R. C.; Stewart, T. D. (1916). "The electromotive force produced by the acceleration of metals". Physical Review. 8 (2): 97–116. Bibcode:1916PhRv....8...97T. doi:10.1103/PhysRev.8.97. PMC   1090978 .
  4. "Archived copy". Archived from the original on 2012-12-21. Retrieved 2013-03-16.CS1 maint: Archived copy as title (link) Retrieved March-16-13
  5. Anderson, Larry (2002). Benton MacKaye: Conservationist, planner, and creator of the Appalachian Trail. JHU Press. p. 136. Retrieved 12 July 2013.
  6. Anderson, Larry (2002). Benton MacKaye: Conservationist, planner, and creator of the Appalachian Trail. JHU Press. p. 48. Retrieved 13 July 2013.
  7. "Book of Members, 1780-2010: Chapter T" (PDF). American Academy of Arts and Sciences . Retrieved 20 April 2011.
  8. Bartky, W. (1927). "Review: Statistical Mechanics with Applications to Physics and Chemistry by Richard C. Tolman". Astrophysical Journal. 66: 143–144. Bibcode:1927ApJ....66..143B. doi:10.1086/143076.
  9. Sterne, Theodore E. (1941). "Review: The Principles of Statistical Mechanics by Richard C. Tolman". Astrophysical Journal. 93: 513. Bibcode:1941ApJ....93..513.. doi:10.1086/144301.
  10. Infeld, L. (July 1939). "Review: The Principles of Statistical Mechanics by Richard C. Tolman". Philosophy of Science. 6 (3): 381. doi:10.1086/286579.
  11. Chant, C. A. (1934). "Review: Relativity, Thermodynamics, and Cosmology by Richard C. Tolman". Journal of the Royal Astronomical Society of Canada. 28: 324–325. Bibcode:1934JRASC..28Q.324C.
  12. 1 2 Reynosa, Peter. "Why Isn't Edward P. Tryon A World-famous Physicist?". Huffington Post. Retrieved March 22, 2016. (See Edward Tryon.)

Books by Tolman