Pacific Northwest Particle Theory Seminar

The Pacific Northwest Particle Theory Seminar is an annual 1.5-day regional meeting for high energy theorists in the Pacific Northwest.

The next meeting will be held at the University of Victoria at:

Date: April 30-May 1, 2026.

Location: Elliott (ELL) (168) on Thursday; Bob Wright Centre (BWC) A104 on Friday.

(See maps below)

Register here

Schedule:

April 30, 2026 (Thursday - ELL 168)

1330 - 1400: Welcome, coffee.

1400 - 1500: Student talks, part 1:

 - Branden Aitken (UVic), Sub-GeV dark matter detection from cosmic ray bremmstralung in the atmosphere.

 - Chuanxin Cui (UBC), Splitting and gluing in sine-dilaton gravity: matter correlates and the wormhole Hilbert space.

 - Ella Henry (UW), Phenomenologist's Guide to the Axiverse. 

1500 - 1530: Break.

1530 - 1650: Student talks, part 2:

 - Raphael Hoult (UVic), Anisotropy and the breakdown of relativistic hydrodynamics.

 - Elliot Maderazo (UW), Black Holes and Abelian Instantons.

 - Riku Mizuta (TRIUMF), X-rays from Inelastic Dark Matter Freeze-in.

 - Jarod Tall (WSU), Double scaled bosonic and fermionic embedded ensembles, complex SYK, and the dual Hilbert space.

1650 - On: Dinner, drinks.

May 1, 2026 (Friday - BWC A104)

0930 - 1000: Welcome, coffee.

1000 - 1100: Tien-Tien Yu (U of Oregon), Illuminating the Nature of sub-GeV Dark Matter.

Abstract: Over roughly the last ten years, the search for sub-GeV dark matter has boomed, spurred by a new generation of experiments. Intriguingly, many report an excess of low-energy events. In this talk, I will explore strategies for sifting through such data to disentangle potential dark matter signals from backgrounds. These strategies emphasize the importance of having diverse probes, utilizing a variety of target materials and detection technologies. By combining these approaches, we can sharpen our ability to determine whether any viable dark matter model can explain the observed excesses, and take concrete steps toward uncovering the particle nature of dark matter in the sub-GeV regime.

1100 - 1130: Break, posters.

1130 - 1210: Joaquin Turiaci (U of Washington), The universe's awkward phase.

Abstract: I will discuss recent developments in the Hartle–Hawking wavefunction of the universe and in the path-integral approach to quantum cosmology. I will also present work in progress on the role of Nariai geometry in our understanding of quantum gravity in de Sitter space.

1210 - 1230: Afif Omar (UVic), Probing Hadronic Dark Matter Annihilation with Big Bang Nucleosynthesis.

Abstract: The first elements in the Universe were synthesized within a few minutes after the Big Bang, in the epoch known as Big Bang Nucleosynthesis (BBN). Precise measurements from astrophysical observations, the cosmic microwave background (CMB), and nuclear reaction rates render BBN an essentially parameter-free theory, making it a powerful test of new physics. In this talk, I will show how BBN can be used to probe residual annihilations of sub-GeV thermal relic dark matter (DM). I will focus on candidates with velocity-suppressed annihilation channels and show that DM annihilation to pions and kaons beyond freeze-out, and their subsequent interaction with protons and neutrons prior to the deuterium bottleneck provide a sensitivity to annihilation that surpasses that of the CMB and indirect detection in the galaxy.

1230 - 1300: Joydeep Chakravarty (McGill), Imaging black holes: exterior and interior.

Abstract: Within holography, we discuss a high-energy simplification which allows us to probe local physics about a bulk point. We find a factorization of boundary correlators in terms of flat-space like scattering amplitudes. Our techniques also allow us to record boundary imprints of bulk causality using lightcones emerging from the bulk point. We then utilize analytic extensions to study the black hole interior: the Schwarzchild singularity using the two-point function, and also obtain similar factorization leading to flat-space scattering amplitudes about an interior bulk point.

1300 - 1400: Lunch.

1400 - 1440: David McKeen (TRIUMF), Neutrinos and their interactions.

Abstract: In the standard model, neutrinos interact solely through the weak force and are the only fundamental fermions with zero electric charge. As such, their masses can be of a qualitatively different nature from those of the other fundamental fermions. Mass models for neutrinos can also give rise to new, non-gauge interactions of neutrinos that are much stronger than the weak interaction. In this talk I will describe some of the ways that these interactions can arise, why they could be interesting, and how to look for them experimentally.

1440 - 1510: Break, posters.

1510 - 1540: Jeremy van der Heijden (UBC), Algebras for generalized entanglement wedges.

Abstract: The geometry of spacetime regions in holography is closely tied to the algebraic structure of the underlying quantum theory. In asymptotically AdS settings, this is manifested through the correspondence between entanglement wedges and boundary subsystems. Bousso and Penington have recently proposed a broader notion of entanglement wedges applicable to more general spacetimes, which retains many of the key structural features familiar from AdS/CFT. In this talk, I will investigate the hypothesis that such generalized entanglement wedges admit an intrinsic algebraic interpretation. Specifically, I will consider a map that associates to each wedge a subalgebra in an underlying (unknown) quantum description, and formulate general properties that such an assignment should satisfy. I will argue that several of the structural relations identified by Bousso and Penington—such as inclusion relations and entropy inequalities—can be naturally understood as consequences of standard properties of entropy in algebraic quantum systems. Finally, I will discuss to what extent these ideas may be realized in simple settings, including tensor network models, and comment on their implications for extending holographic intuition beyond the AdS context.

1540 - 1610: Qinrui Liu (SFU), Dark Matter with Neutrino Telescopes.

Abstract: The searches for dark matter (DM) with neutrino telescopes have primarily focused on annihilation or decay signatures in galactic halos and celestial bodies. Beyond the generic scenarios of WIMPs with mass at GeV-TeV, however, a wide range of DM models and astrophysical environments remain largely unexplored. In this talk, I will discuss novel avenues for probing DM using neutrino telescopes, incorporating alternative scenarios such as inelastic and asymmetric dark matter. I will explore the physics reach across an expansive mass range—from sub-GeV to ZeV—and in diverse systems ranging from the Earth’s core and neutron stars to the DM Halo and active galactic nuclei.

1610 - 1640: Break, coffee.

1640 - On: End, dinner, drinks.

The Bob Wright Centre at the University of Victoria is located at

3800 Finnerty Road, Victoria BC, V8W 2Y2

For a map of the campus, including Elliot and Bob Wright Buildings, click here.

There are many off-campus options for lodging. (Unfortunately on-campus housing is only available after the meeting, from May 8 on.)

• The cheapest option is the Ocean Island Inn, a hostel downtown with rates of O(40-50) CAD/night.
• There are many hotels in, or near the Inner Harbour ranging in costs from O(120) CAD/night to 1/epsilon. You should be able to find reasonable rooms for about 140-160 CAD/night after some digging on the usual aggregators, like Kayak, Hotels.com, &c.