GRAPPA Centre

Come join us at @GRAPPAinstitute! Keep an eye on grappa.amsterdam/jobs/ for open PhD, Postdoc and Tenure-Track positions at @GRAPPAinstitute (as well as related positions at @uva_api).

Huge congratulations to our new Dr. Uddipta Bhardwaj 🥳 we are most proud of you!

Applying it to the case of dark matter (DM) spikes around massive black holes (BHs), they show that a fully relativistic treatment is needed to accurately model the environmental dephasing of gravitational wave (GW) signals from EMRIs

New GRAPPA paper! arxiv.org/abs/2505.09715 The authors (Rodrigo Vicente, Theophanes Karydas, @gfbertone) introduce a relativistic framework to model environmental effects on extreme mass-ratio inspirals (EMRIs) in collisionless media

Today we had a fantastic Colloquium by Dr. Malcolm Fairbairn (@KingsCollegeLon) to tell us about "Galaxies, Axions, Gravitational Waves, Black Holes and More Galaxies"

It's a real pleasure to have Dr. Jonathan Gair (@mpi_grav) giving the GRAPPA Colloquium today, to tell us about "Opportunities and challenges in SBI for future gravitational wave detectors"

He will use it to conduct six months of research at DESY, the German laboratory for high-energy physics in Berlin.

Huge congrats to @JaccoVink for receiving the prestigious German Humboldt Prize for research! astronomie.nl/nieuws/jacco-v…

Inspiring and wonderful article about former GRAPPA PhD student @gimmytomas in dutch newspaper NRC. Congratulations! pressreader.com/netherlands/nr…

We had a busy & wonderful day ⁦@GRAPPAinstitute⁩ yesterday with 2 PhD defences! Huge congratulations to Dr Montel ⁦@AnauNoemi⁩ & Dr Tomaselli on their brilliant theses & defences. Such an honour to be on your defence committees. We are so proud of you & wish you the..

It was fantastic having you the last 4 years at the Institute, you have been a key part of GRAPPA and we will certainly miss you! We wish you all the best for the future 🎉

Huge congratulations to Dr. Anau Montel and Dr. Tomaselli for brilliant PhD defences today! 🥳🥳🥳

Huge congratulations to Dr Tomaselli for a brilliant PhD defence and beautiful thesis, with cum laude & many congratulations to the proud supervisors Gianfranco Bertone @DD_Baumann @GRAPPAinstitute

Congrats to all the authors! Oleg Savchenko, Florian List, @GFAbellan, @AnauNoemi @C_Weniger

Owing to its simplicity, the method is significantly faster than other proposed algorithms (training only takes ~1h on a GPU, and sampling just ~3s for 1000 samples), while still being highly precise and interpretable

The method relies on the assumption that the multi-million dimensional posterior of cosmic ICs can be described by a simple Gaussian, where the mean and covariance have been trained on the Quijote N-body simulations suite

Paper alert! The authors introduce a fast and accurate method to reconstruct the cosmological initial conditions from present-day dark matter density fields, including uncertainty quantification! arxiv.org/abs/2410.15808 Led by GRAPPA PhD Oleg Savchenko

This is the paper journals.aps.org/prx/abstract/1…

PBS Space Time has picked up a PRX paper by current and former GRAPPA members. Huge congrats to Dion Noordhuis, Anirudh Prabhu, Sam Witte and @C_Weniger for the fantastic piece of work! youtu.be/W4SnKp4BhP4?si…

The work was done by Dion Noordhuis at @GRAPPAinstitute, Anirudh Prabhu (@Anirudh_14) at @Princeton, Christoph Wenigerat (@C_Weniger) the @GRAPPAinstitute, and Samuel J. Witte at @GRAPPAinstitute.

All active #NeutronStars should be surrounded by dense #AxionClouds if the axion has a mass in a specific range. This occurs because the polar caps of neutron stars produce axion clouds that are bound to the star and struggle to dissipate energy. 🔗 go.aps.org/4hbgocF