Senior Thesis Presentations - Flynn, Hamil, Hellmers and Zubairi

Time: 2 PM, Friday, Dec 7th, 2007

Place: P-148 (refreshments will be served at 1:45 PM in P145A)

Mitochondrial Stereology from the Statistics of Sections
Daniel Flynn
When the mitochondrial network within the cell is in a fragmented state, it resembles a spatial distribution of prolate spheroids of various shapes, sizes and orientations. The cell is studied by making electron micrographs which amount to a series of planar slices through that spatial distribution. These micrographs exhibit sections of individual mitochondria, which have roughly elliptical shape. This paper uses a maximum-likelihood scheme to infer the distribution of spheroidal shapes, sizes and orientations from the observed distribution of elliptical sections.

Investigation of the limiting energy density of compact stars
Oliver Hamil
This research is an attempt to find the limiting energy density for compact stars using a variational ansatz for the unknown equation of state of ultra-dense nuclear matter. The Harrison-Wheeler/Negele-Vautherine equation of state is used for the outer/inner crust regime of compact stars up to nuclear density, and is assumed to be the valid equation of state for this region. Beyond nuclear density, the equation of state is almost completely unknown and is thus created using a variational ansatz. The equations of state generated from this ansatz are constrained by causality (in the high pressure regime), and microscopic stability (Le Chatelier's principle). We also assumed that Einstein's theory of General Relativity is the correct theory of gravity. The equations of state generated from the variational ansatz are used to generate stellar sequences of compact stars in order to investigate energy density limits for stars of given masses. From this data, conclusions can be drawn about phase transition regions within compact stars at certain densities. Also, knowing the mass limit for compact stars is of key importance for estimating the number of low-mass black holes in Galaxies.

Folding and Local Equivalent Potentials for Pycnonuclear Reactions
Joseph Hellmers
We are undertaking a research program to calculate Pycnonuclear Reaction Rates using different nuclear models and potentials. In order to calculate these Pycnonuclear reaction rates it is necessary to be able to calculate the Folding and Local Equivalent Potentials. This presentation will review the concepts, our intended course of action and the results thus far.

The Cosmological Constant And Compact Stars
Omair Zubairi
The Cosmological Constant was originally proposed by Albert Einstein in 1916 as a modification of his field equations of General Relativity to achieve a stationary Universe; however, in 1929 Edwin Hubble discovered the Universe is not static but expanding. Recently, scientists have discovered this expansion rate is even increasing - leading to an 'Accelerating Universe'. This acceleration which is caused by cosmic forces known as Dark Energy and Dark Matter will change the solutions to Einstein's field equations. This research project explores these different solutions for compact spherically symmetric stellar objects such as neutron stars and black holes.

You can view other undergraduate thesis abstracts.
Or via the digital thesis archive.