AstroPhysics Group Research
The AstroPhysics Group at Shepherd is involved in several areas of research,
and has published and presented multiple works in the following areas.
RESEARCH SYNOPSIS: The Group's research attempts to address two
fundamental problems in cosmology:
- On the largest scales, the Universe is believed to be everywhere
homogeneous and isotropic: this is the Copernican cosmological
principle. It is evidentially verified by such observations as the
isotropy of the cosmic microwave background, the x-ray background, and
the number counts of radio sources. However, on smaller scales,
the universe is certainly not homogeneous: galaxies are observed to be
distributed not at random, but clustered with respect to each other.
Any theory of structure formation must take this disparity on multiple
scales into account.
- For some time it has been known that the morphological
fractions of ellipticals, lenticulars, and spirals are
related to the density of the environment.
The fraction of ellipticals ranges from less
than 10% in the lowest density environments to more than
50% in the centers of galaxy clusters. It is still not
apparent whether this is a result of conditions
conducive to formation of a particular morphological type
(nature) or to an evolutionary process (nurture).
The particular behavior of astronomical clustering on multiple scales
suggests that the concepts of fractal geometry
may apply. The modern motivation for fractal geometry may best be
summed up by this quote of Benoit Mandelbrot: ``Mountains are not
cones, clouds are not spheres, coastlines are not circles, and bark
is not smooth, nor does lightning travel in a straight line''.
Fractals are, in simplest terms, objects which are (approximately)
self-similar on all scales.
The research focuses on the use of the pointwise dimension
(which is based on fractal geometry) to understand both the large-scale
structure of the universe and the connection between galaxy morphology
An Examination of the Large-Scale Clustering
of the Las Campanas Redshift Survey
RESEARCH SYNOPSIS: Our expanded facilities allow us to provide research opportunities for
students in a number of observational fields. A collection of images can
be found at the Shepherd University Observatory's dedicated website.
FOR MORE INFORMATION:
Shepherd University Observatory
RESEARCH SYNOPSIS: Keeping an eye to the past allows us to better
understand the developments leading to the present state of the
and gives us a more confident position from which to direct future
efforts in astronomy. The Group is currently working on
a long-term study and critique of historical developments in astronomical
thought in the 16th and 17th centuries, and the applications
in modern astronomical education.
Copernicus's Neglected Successor (Mercury)
RESEARCH SYNOPSIS: Three-dimensional simulations and visualizations
of astronomical data are invaluable to the astronomer. Seeing
astronomical objects in three dimensions (as opposed to the two
dimensions our sky limits us to) allows visual evaluations and
facilitates clearer and deeper understandings of the physical
situations underlying the results of mathematical analyses. We use an
SGI O2 workstation on-site on which we develop our models. We also have
remote access to ImmersaDesk and CAVE (CAVE Automatic Virtual
Environment) hardware and software.
A Java 3D visualization application for research use in astronomy
(Journal of Computing Sciences in Colleges)