Welcome to Tabitha!

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Tabitha is the home on the web for our theoretical astrophysics group at UBC. The current members are

Ilaria Caiazzo Jeremy Heyl Javiera Parada
T-bird.jpg Jeremy.jpg T-bird.jpg

Collaborators / Colleagues / Alumni

Dastegir Al-Quaderi Asha Asvathaman Jonathan Benjamin Flora Ge Ramandeep Gill Ryan Goldsbury
Kelsey Hoffman Amber Hollinger Dong Lai Yoram Lithwick Don Lloyd Maxim Lyutikov
Derek MacKay Dan Mazur Mark McAnerin Martha Milkeraitis Kaya Mori Alysa Obertas
Conor Omand Rosalba Perna Matthew Penrice Chenruo Qi Harvey Richer Raminder Samra
Ryan Shannon Nir Shaviv Anand Thirumalai Hong Tsui Melody Wong

The research in the group ranges over the following areas:

  • Cosmology, Galaxy formation, evolution and mergers,
  • General relativity,
  • Properties of materials and the vacuum in ultrastrong magnetic fields,
  • Physics of neutron stars,
  • Magnetic and relativistic stellar structure,
  • Dynamics, formation and evolution of globular clusters

Presently our research is mostly focussed on the last four bullets. The theme running though our work is how how is our understanding of astrophysical phenomena connected with our understanding of fundamental physics. Although our work so far has emphasized compact objects (white dwarfs, neutron stars and black holes), the physics of the early universe and cosmology in general also provides a window onto fundamental physics.


Magnetized-atom breakthrough

Anand Thirumalai and Jeremy Heyl present the state-of-the-art calculations of atoms in strong magnetic fields in a series of papers on the arXiv: arXiv:0806.3113 and arXiv:0903.0020. Strong magnetic fields distort the structure of atoms.  To the left is depicted the ground state and first excited state of hydrogen in no magnetic field and in a field for a typical neutron star.   The magnetic field points up and down. Notice how much the electron is squished along and across the vertical direction. Anand Thirumalai and Jeremy Heyl have developed a software suite to calculate accurately the structure of magnetized atoms in arbitrarily strong magnetic fields  even in intermediate regimes where neither nucleus and magnetic field dominates.   So far they have built neutral hydrogen, helium and lithium.  Not only do the results agree with the zero field results but are more accurate than previous work even for strong fields and up to 10,000 times faster.  Below is the wavefunction for the less bound electron of helium in magnetic fields ranging from 6 × 107 G to 6 × 1010 G.  The Earth's magnetic field is about 0.1 G.

We have now produce a new version to extend these results to even stronger fields. Check it out at 1203.3437.

The left panels give the ground and excited state of hydrogen in no magnetic field. The right panels give the same states in a neutron-star field of 1012 G.