Jekyll2026-09-14T06:32:20+00:00https://davidegerosa.com/feed.xmldavidegerosa.comUniversity professor - research in gravitational waves, black holes, and applied statistics.Davide Gerosadavide.gerosa@unimib.itgweccentricity in Corfu2026-09-06T00:00:00+00:002026-09-06T00:00:00+00:00https://davidegerosa.com/posts/gweccentricity-in-corfuI just had the pleasure of organizing an amazing workshop, “Binary compact objects on eccentric orbits and their gravitational-wave signatures,” in beautiful Corfu, Greece. Huge thanks to Isobel Romero-Shaw, Rossella Gamba, and Michalis Agathos for organizing it with me.

We learned that defining eccentricity is scary and that there are too many definitions—but also that perhaps we don’t need to agree on one, as long as we can convert between them. We learned that the waveform folks are making outstanding progress on eccentric, precessing, and inspiral-merger-ringdown models. We learned that a starfish is cute, that seafood moussaka is a nice variation and that, when the coffee machine doesn’t work, nothing really works.

I was also very proud to see several current and former group members at the forefront of (eccentric) gravitational-wave research.

Here are some pictures, as well as the list of the sessions.

Lake July 2026a

Lake July 2026b

Program in a nutshell

  • Detecting eccentricity: current evidence and future prospects
  • How do you quantify it? Gauge dependence and invariant definitions of eccentricity
  • Astrophysical implications of orbital eccentricity: standard paradigms and new ideas
  • Challenges and new approaches to modelling GWs from eccentric binaries
  • Mild eccentricity, major consequences: astrophysical
mis-inferences, waveform systematics, and tests of GR
  • What’s next for GW eccentricity?
]]>Davide Gerosadavide.gerosa@unimib.itGroup summer activity at the lake2026-07-21T00:00:00+00:002026-07-21T00:00:00+00:00https://davidegerosa.com/posts/group-summer-activity-at-the-lakeWe just had a fun social activity with our research group. We all went swimming in Lake Iseo! It’s one of the lakes in Northern Italy; this spot specifically, called Zorzino. There were quite a lot of us! Myself; Tristan, Ssohrab, and Alex (postdocs); Matilde, Matteo, and Giulia (PhD students); and Emma, Martina, Giulia, Lisa, Alessia, Rocco, and Sofia (all MSc students). Chiara and Federico were spiritually with us from abroad ;-) Enjoy the summer now; at the next group meeting, we might even talk about science.

Lake July 2026a

Lake July 2026b

]]>Davide Gerosadavide.gerosa@unimib.itStudents graduating in July2026-07-21T00:00:00+00:002026-07-21T00:00:00+00:00https://davidegerosa.com/posts/students-graduating-in-julyThree more students graduated with projects with us in July…

  • Giacomo Brugali completed his BSc project with Matteo Boschini and me, with a funny investigation on entropy in black-hole binaries. He’s now moving to the Netherlands for his MSc.
  • Marco Bianchi got his MSc degree in Astrophysics with a computational project on GPUs, Short-Fourier Transforms, and binary neutron stars. Marco secured a PhD position at GSSI (L’Aquila) starting next year, congrats!
  • Giorgio Monti completed his MSc project externally under Andrea Maselli and Sayak Datta at GSSI (L’Aquila), while I had the pleasure of signing as internal supervisor and chatting with them multiple times. Giorgio worked on extreme mass ratio inspirals (EMRIs) embedded in dark matter profiles.

Congrats all, thanks for working with me.

]]>Davide Gerosadavide.gerosa@unimib.itNational PhD in AI (can be hosted here!)2026-07-19T00:00:00+00:002026-07-19T00:00:00+00:00https://davidegerosa.com/posts/national-phd-in-ai-can-be-hosted-hereApplications are open for the Italian National PhD in AI:

phd-ai-society.di.unipi.it/applications

National PhDs are centralized programs, where applications are collected by a single institution (in this case, the University of Pisa), while students carry out their research at a range of participating institutions. In particular, this year there are two positions titled “Accelerating Physics Research Using Artificial Intelligence”, funded by INFN (the Italian National Institute for Nuclear Physics). These positions can be hosted by any research group affiliated with INFN, including my own. If you’re interested in applying, please send me an email!

]]>Davide Gerosadavide.gerosa@unimib.itFun project: automatic seminar reminders2026-07-13T00:00:00+00:002026-07-13T00:00:00+00:00https://davidegerosa.com/posts/fun-project-automatic-seminar-remindersI recently had some fun setting up a bot that sends automatic reminders for our group seminars (if you’ve ever done it, you know that remembering to send seminar emails is a pain). Let me share it here in case it is useful to others:

github.com/dgerosa/astroseminars_bicocca

Some of the things I learned:

  • My goal was to have a single entry point where people organizing seminars can add their speakers, and then everything else is handled automatically. I set this up using a shared group calendar.
  • The script fetches data from the calendar and sends emails. It turns out that the easiest way to send emails is to set up a dedicated Gmail account; ours is called astrobicocca.bot@gmail.com. You also need to generate what Google calls an “app password,” which is different from the full Google account password.
  • The code runs via a GitHub Action, with that password inserted a GitHub secret
  • For running this automatically, it turns out scheduled (cron) GitHub Actions are not always reliable, so I use our computing system, redfive, to trigger the GitHub Action itself. If anyone has a better solution, please let me know!

The system has now been deployed for a few months, and it has been working very well. Every Friday, it sends a summary of the following week’s events, and on seminar days it sends a reminder early in the morning.

]]>Davide Gerosadavide.gerosa@unimib.itBiCoQ and Uli Sperhake visiting2026-06-22T00:00:00+00:002026-06-22T00:00:00+00:00https://davidegerosa.com/posts/bicoq-and-uli-sperhake-visitingLast week we had a nice conference here at Milano-Bicocca, centered on the new BiCoQ initative which brings together activites in gravity and particles in our department. Among the invited speakers we had Steve Fairhurst (Cardiff, LVK Spokesperson), Nora Luetzgendorf (ESA, LISA project scientist), and Uli Sperhake (Cambridge, numerical relativity).

Uli is staying for an extra week to work with us; he was my PhD supervisor some 10 years ago (best supervisor ever!), and I’m super happy he’s around visiting my group now.

]]>Davide Gerosadavide.gerosa@unimib.itPopulation-level correlations in Bayesian statistics: an illustrative model for gravitational-wave astronomy2026-06-21T00:00:00+00:002026-06-21T00:00:00+00:00https://davidegerosa.com/posts/population-level-correlations-in-bayesian-statistics-an-illustrative-model-for-gravitational-wave-astronomyCorrelations are the new populations. After GW population analyses have (kind of) nailed down the marginal distributions of masses, spins, and redshift, the focus is now shifting to correlations between two or more parameters. Here, we take a step back and use a simple toy model to understand how correlations (or fake evidence for correlations) can emerge in hierarchical Bayesian statistics when combining individual measurement uncertainties and selection effects. So, lots of Gaussians in this paper.

C. B. Owen, A. Toubiana, D. Gerosa.
arXiv:2606.21076 [gr-qc].

]]>Davide Gerosadavide.gerosa@unimib.itTargeting black holes from metal-poor progenitors with next-generation gravitational-wave detectors2026-06-04T00:00:00+00:002026-06-04T00:00:00+00:00https://davidegerosa.com/posts/targeting-black-holes-from-metal-poor-progenitors-with-next-generation-gravitational-wave-detectorsWe have a 3G paper today, led by Federico Leto di Priolo (recent MSc graduate here) and also featuring a new collaboration with Martyna Chruślińska from ESO. A 3G detector will see black holes at high redshift, which means they will come from stars with different properties—namely, stars with low metallicity. Now, how far should you look if you’re specifically interested in the low-metallicity population (that is, what’s your “target redshift”)? And how many events do you need to do astrophysics there?

F. Leto di Priolo, M. Chruślińska, D. Gerosa.
arXiv:2606.03776 [astro-ph.HE].

]]>Davide Gerosadavide.gerosa@unimib.itredfive standing by2026-05-01T00:00:00+00:002026-05-01T00:00:00+00:00https://davidegerosa.com/posts/redfive-standing-byIn the past few months, we’ve been setting up a new computer cluster called redfive (why redfive?…). Right now, it consists of a login node and five compute nodes, totaling about 100 CPUs. It is developed and maintained entirely in-house (mostly by Rodrigo Tenorio and Federico De Santi, while I prepare coffee during their admin sessions!), which is great fun. It’s not meant to substitute a supercomputer, of course, but rather to provide a simple, easy-to-expand, no-queuing setup for mid-sized jobs, as well as a way to introduce students to remote servers. We need a GPU now!

redfive

]]>Davide Gerosadavide.gerosa@unimib.itGravitational-wave astronomy requires population-informed parameter estimation2026-04-20T00:00:00+00:002026-04-20T00:00:00+00:00https://davidegerosa.com/posts/gravitational-wave-astronomy-requires-population-informed-parameter-estimationUninformative priors are good because they’re uninformative, right? Not really. We argue they’re bad because they are uninformative, i.e. they leave out information. Now, that’s the best you can do if you don’t have that information, but if you do and decide to ignore it, then it becomes your fault. This is the case in our beloved GW astronomy. When we analyze a GW event, we do have some information on what it should look like because we’ve seen many other events. If we ignore that information, then it’s no surprise that the results can be crazy biased.

M. Mould, R. Tenorio, D. Gerosa.
Physical Review D 114 (2026) L021302. arXiv:2604.15885 [gr-qc].

]]>Davide Gerosadavide.gerosa@unimib.it