Josiah Willard Gibbs Jr 1839 1903 American Physicist

Josiah Willard Gibbs, Jr. (1839 -1903) American Physicist, Engineer, Chemist, Mathematician.

Josiah Willard Gibbs, Jr. (1839 -1903) American Physicist, Engineer, Chemist, Mathematician. Obviously, Josiah Willard Gibbs shouldn’t be confused with Special Agent Leroy Jethro Gibbs of “NCIS”!! (Actor Mark Harmon)

Josiah Willard Gibbs, Jr. (1839 -1903) American Physicist, Engineer Chemist, Mathematician. One of the Greatest Scientists of the 19 th Century!! A Genius!! Made Major Contributions to: Gibbs as a young man • Thermodynamics, Statistical Mechanics, Chemistry (Chemical Reaction Theory!!), Math & Mathematical Physics (1 st to develop Vector Mathematics, especially Vector Calculus!!). • First to formulate the Thermodynamic Equilibrium of a system in terms of energy & entropy. • First to develop theories of Chemical Equilibrium, & Equilibrium Between Phases (Gibb’s Free Energy…)

• Physicists think of Gibbs as a Physicist. • Chemists think of him as a Chemist. • Founded a field overlapping physics & chemistry. Physicists call it “Chemical Physics” Chemists call it “Physical Chemistry” • Einstein called Gibbs “The greatest mind in American history. ” • His thermodynamics & statistical mechanics studies were the foundation for many of Einstein’s discoveries. • He is known as “The Father of Vector Analysis” (formal study of vectors in math). • He’s largely responsible for widespread use of vectors in physics, replacing the quaternions that W. R. Hamilton had earlier developed. Gibbs in his 30’s Gibbs in middle age

• Feb. 11, 1839: Born in New Haven, Connecticut. His father was a Professor of Sacred Literature at Yale Divinity School. • Attended Yale. Got prizes in Math & Latin. • 1858: Received BS in Physics from Yale. • 1863: Received Engineering Ph. D from Yale. 1 st Engineering Ph. D ever granted by a US university! • Tutored at Yale: 2 years Latin & 1 year "natural philosophy. “ 1866 -1869: Studied in Europe. • 1866 -1868: Paris 1868 -1869: Heidelberg & Berlin. Worked with Helmholtz! • 1869: Returned to Yale as a faculty member. Gibbs as an older man

• 1871: Yale appointed him Professor of Mathematical Physics (Note: He was only 32 years old!) This was the 1 st Professorship in Mathematical Physics in the US! • Curiously, for 9 years (!) this was a job for ZERO PAY!! • He accepted a job with no salary because he was “not in need of money”! • Yale didn’t want to pay him because, when he was hired, he hadn’t published anything! • 1890: Johns Hopkins U. (Baltimore) offered him $3, 000/yr. This caused Yale to offer him (only!) $2, 000/yr to stay. • Stayed at Yale until his death in 1903. Gibbs as an older man

Some J. Willard Gibbs Accomplishments • “Father” of physical chemistry • Coined the term 'enthalpy' • Gibbs free energy • Gibbs entropy • Vector analysis • Gibbs-Helmholtz equation • Gibbs-Duhem equation • Gibbs algorithm • Gibbs distribution

Some J. Willard Gibbs Accomplishments • “Father” of physical chemistry • Gibbs state • Coined the term 'enthalpy' • Gibbs phenomenon • Gibbs free energy • Gibbs paradox • Gibbs entropy • Gibbs phase rule • Vector analysis • Gibbs-Thomson effect • Gibbs-Helmholtz equation • Gibbs isotherm • Gibbs-Duhem equation • Gibbs-Donnan effect • Gibbs algorithm • The Gibbs lemma • Gibbs distribution

Gibbs’ Paradox • Initially, it was a mystery worthy of Leroy Jethro Gibbs & his fantastic NCIS detective team! • But, instead of waiting for the solution until 21 st Century detectives & technology could solve it, it was solved by the 19 th Century scientist J. Willard Gibbs himself in a manner that, in retrospect, gives us somewhat of a “preview” of 20 th Century Quantum Mechanics!