[Astro] [CAPT] CAPT Weekly Bulletin (w/c 11-05-26)

Mon May 11 08:04:40 BST 2026

Monday 11th May at 3pm, A113 CAPT – Theoretical Physics Student Seminar

Thomas Martin

Brownian Motion and Critical Dynamics

---

Tuesdays at 11am, CAPT Foyer – Astro Coffee

Tuesdays at 11.30am, A113 CAPT – Astronomy Journal Club

Tuesday 12th May at 1pm, C12 Physics – Particle Cosmology and Gravity Seminar

Katy Clough (Queen Mary, London)

Probing beyond GR and the Standard Model using gravitational waves

I will discuss recent numerical simulations that model deviations from the vacuum BH + GR paradigm in the strong field regime of comparable mass black hole mergers. I will review recent advances, and highlight the challenges ahead to properly model these effects and test them in real data.

Link to join: https://teams.microsoft.com/l/meetup-join/19%3ameeting_OGM3OTk5NzQtZWEwZS00ZmUyLTk3MGUtZjFhY2M5OTU2MjI1%40thread.v2/0?context=%7b%22Tid%22%3a%2267bda7ee-fd80-41ef-ac91-358418290a1e%22%2c%22Oid%22%3a%22f3250584-4b5f-48fa-a897-08e77f2246b7%22%7d
---

Wednesday 13th May at 2pm, A113 Physics – Particle Cosmology and Gravity Seminar

Maria Mylova (IPMU, Japan)

Gauge fixing in open quantum systems

Understanding how to gauge-fix open quantum field theories is essential for building consistent open frameworks for cosmology and gravity, where gauge symmetry must coexist with dissipation and noise and decoherence. I will present our recent work developing explicit top-down constructions of open effective field theories (EFTs) for gauge degrees of freedom, with particular emphasis on the role of gauge fixing. We implement BRST quantisation on the Schwinger-Keldysh contour and show that the in-in boundary conditions reduce the doubled global BRST symmetry to a single diagonal copy. This diagonal BRST symmetry is nevertheless sufficient to guarantee that the influence functional remains gauge invariant under two independent gauge transformations, retarded and advanced, independently of the choice of initial state, the presence of symmetry-breaking phases, and whether the gauge theory is Abelian or non-Abelian. I will also remark that once a consistent quantisation scheme is chosen, the Schwinger-Keldysh path integral is uniquely determined, and with it the rules that constrain the construction of open EFTs.  I will conclude by outlining bottom-up implications, and how these principles provide a systematic route to causal, gauge-invariant open EFTs suitable for cosmological and gravitational applications.

Based on:
Gauging Open EFTs from the top down https://arxiv.org/abs/2512.17089
Schwinger-Keldysh path integral for gauge theories https://arxiv.org/abs/2604.26941

Link to join: https://teams.microsoft.com/l/meetup-join/19%3ameeting_OGM3OTk5NzQtZWEwZS00ZmUyLTk3MGUtZjFhY2M5OTU2MjI1%40thread.v2/0?context=%7b%22Tid%22%3a%2267bda7ee-fd80-41ef-ac91-358418290a1e%22%2c%22Oid%22%3a%22f3250584-4b5f-48fa-a897-08e77f2246b7%22%7d

Wednesday 13th May at 3.45pm, C4 Physics – Astronomy Weekly Seminar

Dr Giulia Lusetti (Open University)

From diffuse cluster emission to compact jets: a LOFAR perspective on the life cycle of radio plasma

Is education as we know it dead? Released in November 2022, ChatGPT is now regularly being used by students and instructors alike for a variety of different purposes within academia. Recent releases of ChatGPT and its analogues have shown incredible promise to scale and be able to pass elements of degree courses. In this talk, we will show our results of applying ChatGPT to an entire Physics BSc degree and how it achieves a (caveated) pass at a 2:1 standard. If it were not for laboratories (or performances in other disciplines), the implementation of invigilated exams, and vivas, it could achieve this outcome undetected. In general, coding tasks are performed exceptionally well, along with simple single-step solution problems. Multiple step problems and longer prose are generally poorer along with interdisciplinary problems, although there are ways to coax better performance. We strongly suggest that there is now a necessity to urgently re-think and revise assessment practice in physics (and other disciplines) due to the existence of AI such as GPT-4. We will describe its current form and limitations and predict what the future might hold including consideration of how AI can be embedded within the disciplinary context using a two lane approach.

---

Thursday 14th May at 1pm, A113 CAPT – Astronomy Lunch Talks

Mathias Urbano
An overview of the Low Surface Brightness Science with the Euclid Space Telescope

During this talk, I will revisit the efforts carried out during my PhD to conduct some of the first studies with Euclid in the Low Surface Brightness (LSB) Universe regime. This will be illustrated through the study of structures spanning three different angular scales: mock dwarf galaxies that I used to assess Euclid’s detection performance in the LSB regime for objects up to arcminute scales; tidal features investigated within the framework of Euclid’s first test observations within a single observation (0.56 square degrees); and the intracluster light of the Fornax cluster, which extends over several degrees.

Paloma Morilla

Signatures of fuzzy dark matter inside radial critical curves

We explore how fuzzy dark matter (FDM) would modify strong gravitational lensing magnification, focusing on the region near radial critical curves. Using simulated galaxy-scale lenses, we compute magnification maps for a range of halo configurations and axion masses. We find that, compared to standard cold dark matter (CDM), FDM produces a significantly higher probability of strong central magnification, an effect that is difficult to reproduce in CDM (even when subhaloes are included). The strength and characteristic scale of this enhancement are set primarily by the de Broglie wavelength, and therefore by the axion mass and halo mass. For galaxy-mass haloes, axion masses in the range $m_\phi~10^{-22}-10^{-21}$ eV lead to distinctive magnification distributions. These results suggest that observations of highly magnified, compact sources near radial arcs could provide a sensitive and complementary test of fuzzy dark matter.

Thursdays at 3pm, A113 CAPT – Particle Cosmology Journal Club

---
Fridays at 4pm, CAPT Foyer – CAPT Cakes
---
If you have any events/visitors you would like included in next week’s bulletin, please let me know.

Best wishes

Ella

Ella Batchelor (she/her)
Administrator

School of Physics & Astronomy

University of Nottingham
A112a Centre for Astronomy & Particle Theory
University Park
Nottingham, NG7 2RD

+44 (0) 115 74 86778 |  nottingham.ac.uk<http://nottingham.ac.uk/>

[cid:image001.png at 01DCDEE1.2218F0E0]

Follow us
facebook.com/uniofnottingham<http://facebook.com/TheUniofNottingham>
twitter.com/uniofnottingham<http://twitter.com/UniofNottingham>
youtube.com/nottmuniversity<http://youtube.com/nottmuniversity>
instagram.com/uniofnottingham<http://instagram.com/uniofnottingham>
linkedin.com/company/university-of-nottingham<http://linkedin.com/company/university-of-nottingham>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.nottingham.ac.uk/pipermail/astro/attachments/20260511/18cf5a46/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.png
Type: image/png
Size: 190221 bytes
Desc: image001.png
URL: <http://lists.nottingham.ac.uk/pipermail/astro/attachments/20260511/18cf5a46/attachment-0001.png>
-------------- next part --------------
_______________________________________________
CAPT mailing list
CAPT at lists.nottingham.ac.uk
https://lists.nottingham.ac.uk/mailman/listinfo/capt