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.
In past years, much of my research has been associated with the
quark model of hadrons. My early work on quarks included the development
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
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.
Shortly after arriving
at Indiana, I helped initiate, with S.Y.Chu, the Indiana University High Energy Theory research contract with the Department of Energy (DOE). The initial one-year Contract in
1970 for the two of us plus graduate student support was for $20,000. The support of the DOE increased over the years, eventually providing funds for additional faculty, two post-doctoral research associates and several graduate students. By the time I stepped aside as the Senior Principal Investigator twenty-five years later, the Contract had grown to
more than $200,000. It continues to be well-funded to this day.
In the last few years, my interests have turned to historical topics involving such figures as Ptolemy, Kepler,
Hooke, Newton, Kelvin and Maxwell. They have included such topics
as Kepler's first (and personal favorite) model of the solar system
(how good was it?), the Hooke-Newton controversy over vertical fall
taking the Earth's rotation into account (where will a falling object
land?), and Kelvin's 100 million year estimate of the age of the Earth
(much longer than 6000 years!).