Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: The nite size of nucleons should play an important role in the description of high density nuclear
matter as found in astro-physical objects. Yet we see that the Walecka model, which is generally
used to describe these systems, treats the nucleons as point particles. Here we argue that a
non-commutative version of the Walecka model may be a consistent and appropriate framework
to describe nite nucleon size e ects. In this framework the length scale introduced through
the non-commutative parameter plays the role of the nite nucleon size. To investigate the
consequences of this description, the equations of motion and energy-momentum tensor for the
non-commutative Walecka model are derived. We also derived an expression for the total energy
of the system, as a function of the non-commutative parameter, in a spatially non-uniform matter
approximation. The non-commutative parameter, as a variable dependent on the dynamics of
the system, remains to be solved self-consistently. / AFRIKAANSE OPSOMMING: Die eindige grootte van nukleone moet 'n belangrike rol speel in die beskrywing van ho e-digtheid
kern materie soos gevind in astro- siese voorwerpe. Tog sien ons dat die Walecka model, wat in
die algemeen gebruik word om hierdie stelsels te beskryf, die nukleone as punt deeltjies hanteer.
Ons redeneer dus dat 'n nie-kommutatiewe weergawe van die Walecka model 'n konsistente en
gepaste raamwerk is om die e ekte van eindige nukleon grootte te beskryf. In hierdie raamwerk
speel die lengte-skaal wat ingevoer word deur die nie-kommutatiewe parameter die rol van eindige
grootte vir nukleone. Om die gevolge van hierdie beskrywing te ondersoek, word die vergelykings
van beweging en die energie-momentum tensor afgelei vir die nie-kommutatiewe Walecka model.
Ons het ook 'n uitdrukking vir die totale energie van die stelsel, as 'n funksie van die niekommutatiewe
parameter, afgelei in 'n ruimtelik nie-uniforme materie benadering. Die niekommutatiewe
parameter, as 'n veranderlike afhanklik van die dinamika van die stelsel, bly
steeds om self-konsistent opgelos te word.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/20255 |
| Date | 03 1900 |
| Creators | Groenewald, Hendrikus Wilhelm. |
| Contributors | Scholtz, Frederik G., Wyngaardt, Shaun M., Stellenbosch University. Faculty of Science. Dept. of Physics. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 62 p. |
| Rights | Stellenbosch University |
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