Academic bio

My academic resume follows.

Academic degrees

  • 2000–2004: Bachelor of Mathematics (Honours), University of Newcastle, NSW. 1st-class honours and a science faculty medal
  • 2005–2007: Graduate Diploma in Theology, Avondale College
  • 2013–2017 (expected): Master of Science (Physics), University of Queensland

Publication

  • MacLaurin & Robertson, “Euler Characteristic in Odd Dimensions”, Gazette of the Australian Mathematical Society 30:4 (2003), p195–199. (arXiv version; the journal’s online past issues only go back to 2004 currently)

See Research for work in preparation. I also run the website ColinsCosmos.com, dedicated to general relativity.

Presentations

Conference talks

  • 2015, 2nd Dec, “Galaxy Cable” (abstract on conference website), Melbourne, Australasian Society for General Relativity and Gravitation conference (ASGRG8)
  • 2016, 8th July, “Static vs Falling: Time slicings of Schwarzschild black holes” (slides on conference website), Vancouver, Canadian Conference on General Relativity and Relativistic Astrophysics (CCGRRA16)
  • 2017, 7th July, “Big Rip in an inhomogeneous universe” (slides on conference website), Toruń, Poland, Inhomogeneous Cosmologies (CosmoTorun17)

Conference poster

  • “Static vs Falling”, updated to “Time slicings of black holes“, presented at 21st International Conference on General Relativity and Gravitation (GR21) in New York City, 2016; joint Asia Pacific Physics Conference and Australian Institute of Physics Congress (APPC-AIP 2016) in Brisbane, Australia, 2016; Probing the Spacetime Fabric in Trieste, Italy, 2017; Between Geometry and Relativity workshop in Vienna, Austria, 2017

Faculty presentations

  • 4th June 2015, Master of Science thesis overview, physics faculty at University of Queensland (UQ)
  • 3rd Sep 2015, “Spatial Metric and Spaghettification”, astrophysics group (plus a few quantum physics visitors!) at the University of Queensland. I introduced the spatial metric aka spatial projector tensor, and used it to show that for a Schwarzschild black hole, the radial distance is dL=1/e dr.
  • 17th Dec 2015, “Galaxy Cable”, astrophysics group at University of Queensland. This was a recap of my first conference presentation on the same topic.
  • 26th April 2016, “Black holes: Static vs Falling perspectives”, astrophysics group at UQ. The usual descriptions of radial distance, curvature of 3-space (Flamm’s paraboloid), time at infinity, etc. are based on the Schwarzschild coordinate perspective, which corresponds to static observers (r>2M) or e=0 observers (r<2M). We get different measurements under generalised Gullstrand-Painlevé coordinates, which correspond to radially moving observers of various energy per mass e.
  • 12th September 2016, “Energy conservation in the universe”. I overviewed standard concepts about energy in relativity, for instance the stress-energy tensor knows nothing of a gravitational field, and total energy density is not localisable. However the “rigid quasilocal frames” formulation concludes that total energy is conserved in relativity.
  • …and numerous others since.
  • 5th October 2017. Big Rip in an Inhomogeneous Universe, UQ astrophysics group

Also a talk to the Brisbane Astronomical Society on 8th Sep 2017

Research

Completed theses for university degrees:

  • Mathematics honours thesis, 2004. “Quantum Even-Dimensional Balls”. In original research, I gave equivalent constructions of “quantum ball” C*-algebras. Supervisor Wojciech Szymanski. Cited here for instance
  • Physics Master’s thesis, 2015. “Expanding Space, Redshifts, and Rigidity: Conceptual Issues in Cosmology”. Redshifts can be interpreted flexibly as due to the stretching of space, gravitational, or Doppler in origin. Other topics also investigated. Supervisor Tamara Davis. See PDF and further description.

My research so far is in general relativity. The following topics are being prepared for publication:

  • Spatial distance, observer-dependent. I show the following tools are all equivalent: adapted coordinates, tetrads, spatial projector, and radar metric, and adapted coordinates. I apply them to Schwarzschild black holes, and discuss a subtlety about the “radial” 4-direction
  • Misconceptions of black holes, see the “Time slicings” poster which has similar content. With Geraint Lewis & Tamara Davis
  • Cosmic cable. The expansion of the universe can be used to generate tension in a long rigid cable, and hence harvest energy. Typical treatments are too “Newtonian” and omit correct: displacement (it is not the usual comoving “proper distance”), “redshift” of force, changing force between frames, etc.
  • Big Rip in inhomogeneous cosmology; inhomogeneity can prevent the rip. With Krzysztof Bolejko

Other

I am the organiser of the general relativity meetings at the University of Queensland.

Professional memberships:

  • 2015–  Australasian Society for General Relativity and Gravitation (ASGRG)
  • 2015–2017:  Astronomical Society of Australia (ASA)

Training:

  • Media presentation training by Peter Buckley and also Dwayne Jeffries