26th Australian Institute of Physics Congress and the Australian and New Zealand Conference on Optics and Photonics

Session

AIP TPG: Gravity +

TPG

11 Dec 2026, 09:00

Belinda Hutchinson Building (The University of Sydney )

Conveners

AIP TPG: Gravity +

• Murray Batchelor

590. Inflationary Universe -- my personal perspective --

Prof. Misao Sasaki (Kavli IPMU, University of Tokyo)

11/12/2026, 09:00

AIP | Theoretical Physics (TPG)

Invited talk

Thanks to the rapid progress in observational cosmology, we have begun to understand the physics of the very early Universe, the inflationary expanding universe. However, our knowledge is still far from complete. Based on my personal perspective, I will first review what inflation is and what we currently know about it. Then I will discuss some recent topics that may improve our understanding...

656. Gravity-induced birefringence of light

Rama Vadapalli (Student)

11/12/2026, 09:30

AIP | Theoretical Physics (TPG)

Contributed Oral

Geometric optics effectively describes electromagnetic wave propagation when the wavelength is much smaller than the characteristic length scale of the medium, making wave phenomena like diffraction negligible. As a result, light propagation in a vacuum is typically modelled by rays that follow null geodesics. However, general relativity predicts that polarization-dependent deviations from...

67. Biophysical modelling of Transcranial Ultrasound Stimulation using neural field equations

Marcus Wilson (University of Waikato)

11/12/2026, 09:45

AIP | Theoretical Physics (TPG)

Contributed Oral

Transcranial Ultrasound Stimulation (TUS) provides a non-invasive method for modulating brain activity with spatial precision. It has application in treatment of neurological and psychological disease, for example depression, epilepsy and Parkinson’s, and for basic neuroscience research. Biophysical effects of TUS have not been fully quantified and physical mechanisms linking pressure and...

584. Comparing Superpositions of Pointlike and Quantum CoM Particle Detectors

Carolyn Wood (The University of Queensland)

11/12/2026, 10:00

1

AIP | Theoretical Physics (TPG)

Contributed Oral

Particle detector models are powerful tools for probing different quantum fields or spacetimes. The dominant model, the Unruh–DeWitt (UDW) detector, describes a pointlike particle interacting with a quantum field along a classical trajectory, with only the particle’s internal state treated as a quantum degree of freedom.Recent studies have moved to include more realistic quantum effects,...

448. Variance-Induced Force Corrections: Laboratory Tabletop Tests

Tien Kieu (Swinburne University of Technology)

11/12/2026, 10:15

AIP | Theoretical Physics (TPG)

Contributed Oral

Coarse-graining a macroscopic body of $N\gg1$ identical subsystems makes collective observables self-average, yet for any nonlinear observable $f(\hat A)$ the strict inequality $\langle f(\hat A)\rangle\neq f(\langle\hat A\rangle)$ leaves a residual that is not washed out by coarse-graining and is fixed by the variance $\sigma^2$ of the underlying state.

In a gravitational potential the...