• Simulating astrophysical phenomena in atomic BECs
• Correlations in atoms dissociated from molecular BECs
• Skyrmions in BECs
• Virtual reality in physics teaching

Objective: Develop methods and experimental proposals for studying quantum field theory in curved spacetime using atomic BEC analogues.

There are many interesting phenomena that arise when quantum fields evolve in regions of strong gravity, such as near black holes. A well known one is Hawking radiation, which provides a mechanism for black hole decay. Unfortunately, there is no experimental evidence for Hawking radiation, nor for many other related phenomena. This project aims to investigate the close analogies between quantum fields in atomic BECs and quantum fields in curved spacetime to find ways of experimentally investigating this physics.

Sebastian Wüester recently completed a Ph.D. in this area (online thesis). Michael Uhlmann is the project Research Fellow for 2008.

Our papers:

• Limits to the analogue Hawking temperature in a Bose-Einstein condensate
• Superradiant scattering from a hydrodynamic vortex

Objective: Explore the Einstein-Podolsky-Rosen type correlations between atoms resulting from dissociation of degenerate quantum gases of molecular dimers.

Dissociation of a dimeric molecule produces two quantum mechanically entangled atoms with equal and opposite momenta in the molecule's rest frame. These atoms have Einstein-Podolsky-Rosen (EPR) type correlations, and hence are of great fundamental interest. It is now possible to produce ultra-cold molecules, and even Bose-Einstein condensates (BECs) of molecules, and then to dissociate them, so that these correlations may be explored experimentally.

In this project we use quantum field simulations to understand the conditions under which the atomic correlations may be observed. This allows us to account for all the quantum physics and to produce data which is similar to that which would be found experimentally.

This project is a collaboration with Karen Kheruntsyan of the University of Queensland node of ACQAO.

Our papers:

• First-principles quantum simulations of dissociation of molecular condensates: Atom correlations in momentum space
• Spatial pair correlations of atoms in molecular dissociation

Objective: To investigate the use of virtual reality simulations in physics teaching. Currently we are developing virtual reality simulations of special relativity: Real Time Relativity. It allows the user to fly around in a world obeying relativistic physics. We are investigating the hypothesis that people can learn relativity by experiencing a virtual relativistic world.

This project would suit a student interested in educational research or computer graphics.

Finding out more: The Teaching Physics Using Virtual Reality project is an investigation of game-like simulations for science teaching.

Our papers:

• Real Time Relativity: exploration learning of special relativity
• Real Time Relativity

Objective: Numerically model methods for producing Skyrmions in dilute gas Bose-Einstein Condensates. The goal is an accurate and convincing demonstration that they can be made by practical methods, such as phase imprinting using lasers. Hopefully, this will give experimentalists the confidence to go ahead and explore the physics of these topological solitons.

Our papers:

• Numerical Study of the stability of Skyrmions in Bose-Einstein Condensates
• Energetically stable particle-like Skyrmions in a trapped Bose-Einstein condensate

Phonon Superradiance in BECs: Sarah Midgley. 2006.
We present the results of one-dimensional simulations of sound waves propagating in a BEC and reflecting from a vortex-like density profile. Using these results as a guide, two-dimensional simulations of sound propagation in a BEC, and reflection from a BEC vortex, are investigated. Online honours thesis.

Superradiance in BECs: Andrew Reid. 2005.
We investigated the possibility of sound wave amplification by vortices in BECS. This is an analogue of Penrose energy extraction from rotating black holes. Online honours thesis.

Visualising General Relativity: Ben Lewis. 2005.
Together with Antony Searle and Susan Scott, we used the general relativistic sofware tool GRWorkbench to produce images that would be seen in strongly curved spacetime. For example, what would it look like to fly through a spacetime wormhole? This follows on from our work on special relativistic visualisation. Online honours thesis.

Theory of Hawking radiation in BECs: Tracy Slatyer. 2004.
We are developing a theory of analogue Hawking radiation from sonic horizons in BECs. Parts of this work are reported in the paper Superradiant scattering from a hydrodynamic vortex, T. R. Slatyer and C. M. Savage. Online honours thesis.

Skyrmions in BECs: Thomas Argue. 2003
This work is reported in the paper Numerical Study of the stability of Skyrmions in Bose-Einstein Condensates .

The quantum dynamics of collapsing BECs: Doug Grimm. 2002.
We investigated the physics of collaping condensates, reported by 2001 Nobel prize winners Weiman & Cornell (Donley et al., Nature vol. 412, pg. 295, 19 July 2001). The focus is on the role of quantum correlations beyond the mean field. Online honours thesis.

The quantum theory of the atom laser: Simon Haine. 2001.
This project computationally modelled the mean field dynamics of atom lasers. It was reported in Stability of continuously pumped atom lasers, S. A. Haine, J. J. Hope, N. P. Robins, C. M. Savage, Phys. Rev. Lett. 88, 170403 (2002). Online honours thesis.