Throughout most of my career, my main research activities have been associated with strong interactions, in particular quarks. During the 1990’s however, my interests shifted to neutrino physics, especially the solar neutrino puzzle. More recently, I have been investigating a number of topics in the history of physics.

PAST RESEARCH

In past years,  much of my research has been associated with the quark model of hadrons.  My early work on quarks included the development of the harmonic oscillator model for baryons.  This model subsequently played an important role in helping organize the spectrum of hadrons, thereby providing a much better understanding of their masses as well as their elastic and radiative widths.

Another project that I enjoyed working on was an analysis of pion-nucleon scattering data up to energies well beyond the range of standard phase-shift analyses.  The method employed the practical approach of an impact parameter representation where the physical processes of diffractive and peripheral scattering can be easily incorporated.  Evidence was found for a considerable number of new high mass, high spin resonances.  These continue to be listed in the biennial Review of Particle Physics by the international Particle Data Group.

Other research topics in high energy scattering have included threshold effects, higher symmetries, metastable exotic mesons, nuclear collisions and structure functions.

In neutrino physics, I developed a simple phenomenological computer model of the Sun based on polytropes to investigate the solar neutrino puzzle, a verified discrepancy between the measured flux of electron-neutrinos from the Sun and the flux predicted by the standard astrophysical model of the Sun. As a result of various experimental observations, this puzzle has now been resolved in terms of neutrino oscillations which follow from the neutrinos having very small but non-zero masses.

RESEARCH CONTRACT

Shortly after arriving at Indiana, I helped initiate the Indiana University High Energy Theory research contract with the Department of Energy. The initial contract of $20,000 in 1970 grew to more than $200,000 per year, supporting at one time four faculty, two post doctoral research associates and several graduate students.  As the Senior Principal Investigator for twenty-five years, I have been particularly appreciative of the continued federal support for the group's research.

CURRENT RESEARCH

In the last few years, my interests have turned to historical topics involving such figures as Ptolemy, Kepler, Hooke, Newton, Kelvin and Maxwell. At present, I am writing an article on the Hooke-Newton controversy over vertical fall (taking the Earth's spin into account), as well as a second installment on how people have determined the age of the Earth (Kelvin's estimate of 100 million years).