Conformal Gravity and Time

Author

Jeffrey Shafiq Hazboun, Utah State University

Date of Award:

5-2014

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Physics

Committee Chair(s)

James T. Wheeler

Committee

James T. Wheeler

Committee

Charles Torre

Committee

Shane Larson

Committee

Eric Held

Committee

Nathan Geer

Abstract

Within the last year, two acclaimed physics experiments have probed further into the extremes of our physical understanding. The Large Hadron Collider, the largest experiment ever constructed, has detected a Higgs boson, which establishes a mass scale for the fundamental particles. The Planck mission satellite has made the most accurate measurements of the cosmic microwave background radiation, which is the oldest data about the early universe we are currently able to measure directly. The mission corroborated the proportions of dark matter and dark energy are all very close to expected values. While these experiments have helped solidify the current working model of physics (general relativity plus the standard model of particle physics), large questions remain about the origins of the main constituents of the universe. Galactic and cosmological scale observations indicate something is missing from the standard model of our universe. The current ΛCDM model of cosmology is named after dark energy (Λ) and cold dark matter, place holders in a model where we know the constituents’ phenomenology, but not their origin. The need for an extension of current physical models is obvious.

Most research in gravity has focused on understanding the geometry of spacetime. We demonstrate how the geometry of spacetime may emerge by starting with a space where time does not exist. Time can emerge as part of a physical theory, instead of assuming its existence from the beginning. Specifically, we look at the symmetry of the equations that define the gravitational interaction and extend those existing symmetries, i.e. giving a theory with more symmetries than standard general relativity. We investigate the consequences of making a theory of gravity that is fully scale symmetric. When we change the units (i.e. meters, feet, pounds, seconds) of our physical measurements locally, we expect the laws of physics to undergo no change. Biconformal space is constructed by requiring this broader class of symmetries. Here, we show how time comes necessarily from the construction of biconformal space. The gravitational theory derived from this construction is more complex than general relativity; however, general relativity arises as a special case of biconformal gravity, a feature any candidate alternative theory of gravity must possess. We illustrate biconformal gravity is a viable successor to general relativity and discuss this in the context of dark matter and dark energy candidates.

Checksum

eb06f7c06d659a654c67d647d4457174

Recommended Citation

Hazboun, Jeffrey Shafiq, "Conformal Gravity and Time" (2014). All Graduate Theses and Dissertations, Spring 1920 to Summer 2023. 3856.
https://digitalcommons.usu.edu/etd/3856