Clayton A. Gearhart's research while affiliated with St. John's University and other places

Publications (6)

Article
In 1920, James Franck together with Fritz Reiche and Paul Knipping found strong experimental evidence that the lowest-lying triplet state in helium is metastable—an atom in this state cannot make a spontaneous transition to the ground state. Even though their evidence was entirely experimental, they tied their results almost inextricably to Alfred...
Article
In 1911, James Franck and Gustav Hertz began a collaboration to investigate the nature of collisions of slow electrons with gas molecules that led to a series of carefully planned and executed experiments, culminating in their discovery of inelastic collisions of electrons with mercury vapor atoms in 1914. This paper tells the story of their collab...
Chapter
Hot objects give off light and heat in the form of electromagnetic radiation whose character changes with temperature. Black-body radiation is such electromagnetic radiation in equilibrium with its material surroundings. By the late 1800s, it was a lively research topic for both theoretical and experimental physicists. Samuel Pierpont Langley (1834...
Article
The quantum made its first tentative appearance in physics in 1900, in Max Planck's (1858–1947) work on black body radiation. But only in 1913 did Niels Bohr (1885– 1962) apply it to the spectrum of hydrogen. How did quantum theory develop in the intervening years? One may conveniently distinguish two themes: a quantum theory of matter, often in eq...
Chapter
The equipartition theorem states that the average energy associated with each separable, quadratic term in the Hamiltonian results in a thermal energy of ½ RT per mole, where R is the gas constant and T the absolute temperature. This theorem, which emerged early in the history of kinetic theory in the nineteenth century, was quickly found to be in...
Article
The specific heat of hydrogen gas at low temperatures was first measured in 1912 by Arnold Eucken in Walther Nernst’s laboratory in Berlin, and provided one of the earliest experimental supports for the new quantum theory. Even earlier, Nernst had developed a quantum theory of rotating diatomic gas molecules that figured in the discussions at the f...

Citations

... Among the students that they shared, three special mentions must be given. The first is to Gustav Hertz, nephew of the more famous Heinrich Hertz, who would go on to win the Nobel Prize for the Franck-Hertz experiment, in which they showed that accelerated electrons moving through mercury vapor could only lose energy in multiples of 4.9 eV [20]. The second special mention is Walter Schottky, the famous inventor and researcher in semiconductor technology. ...
... He always worked from the theoretical side." However, others, such as Gearhart in [6] states, "Wien (...) also had a hand in the experiments." Despite these differences, I am under the belief that Wien had some role in the experiments. ...
... In particular there is no invariant information contained in the tree-level S (0) other than its value, which in the low-energy effective field theory merely represents a renormalized coupling constant; an input parameter. However, in the spirit of [7][8][9][10], nonlocal quantum corrections to S do offer unambiguous, intrinsic data, directly constraining models. To give a simple example, discussed in more detail under (8.17), say someone posits that for pure 3D gravity, the sought-after microscopic entropy is S micro = log d(N ), where d(N ) is the number of partitions of N . ...