Physics and Astronomy Colloquium Series

Next Seminar

Thursday, February 16
4:00 PM

Dr. Kassahun Betre
Stanford University

"Spacetime Geometry from Quantum Graphity"

Abstract: 

Quantum Graphity has been proposed as one approach towards a theory of Quantum Gravity in which a fully quantum mechanical, background independent system in the high energy gives rise to a low energy state that resembles ordinary spacetime through ensemble averaging. The high energy states of the Quantum Graphity system are random graphs with microscopic degrees of freedom that live on the edges and vertices. With a suitably chosen Hamiltonian, the low energy limit of the system will become a discretized regular lattice. While this program is promising, much work remains to be done to show that low dimensional Riemannian geometric structure and General Relativistic dynamics can result through statistical mechanics.

Two important aspects to this program are: First, further rigorous formulation is required to arrive at the precise way in which geometric notions of the low energy regular lattice are related to the graphs of the high energy system. Second, a suitable Hamiltonian that will give rise to a regular lattice in the low energy limit needs to be determined. In this colloquium, I will give an overview of the program of Quantum Graphity and progress made so far in the field. I will then describe a new approach towards a suitable Hamiltonian that can generate uniform dimensions in the low energy limit.

The Physics and Astronomy Colloquium Series is open to all members of the university. Unless otherwise noted, talks are held on Thursday afternoons at 4:00-5:20 in Mendocino 1015. Schedule is regularly updated as dates, titles, and abstracts are received. Please check back often. To receive updates about the Colloquium Series, please join our Events Mailing List. For past semesters' series, see our archive.

Spring 2017 Semester Schedule

February 7, 2017
*Note: Tuesday Colloquium*
Dr. Rodolfo Barniol Duran
Purdue University
"Following Astrophysical Jets from Birth to Glory"

February 9, 2017
Dr. Samantha Fonseca dos Santos
Drake University
"Electron and Photon Impact Induced Processes in Molecules"

February 14, 2017
*Note: Tuesday Colloquium*
Dr. Joshua Willis
Abilene Christian University
"Finding a Needle in a Haystack: LIGO's First Observations and Gravitational Wave Searches"

February 16, 2017
Dr. Kassahun Betre
Stanford University
"Spacetime Geometry from Quantum Graphity"

March 2, 2017
Prof. Sebastian Wachsmann Hogiu
McGill University and UC Davis
"Point of Care Technologies for Blood Testing"

March 30, 2017
Dr. John Ready
UC Davis Medical Center
Topic: Medical Physics

April 6, 2017
Prof. Monika Schleier-Smith
Stanford University
TBA

April 20, 2017
Mr. Henry Garcia
Pixar Animation Studios
Sacramento State Physics Alumnus
TBA

May 4, 2017
Senior Project Talks

May 9, 2017
Senior Project Talks

May 11, 2017
Senior Project Talks