September 13, 2018
We all know Doppler shifts, right? That’s like the biibouuubiiiiboouuuuuu of an ambulance. That happens to gravitational waves as well. Suppose you have a merging binary which is emitting gravitational waves (bibooou). If that binary is going somewhere (say it’s … Continue reading
September 10, 2018
I was recently awarded the 2018 Giulio Rampa Thesis Prize for Outstanding Research in General Relativity. The prize is sponsored by the University of Pavia (Italy) and the Italian Society for Relativity and Gravitational Physics (SIGRAV), and was officially awarded … Continue reading
August 7, 2018
Today’s paper celebrates the wedding of startrack and precession (the nickname for this project was pretrack 😉 ). We use population synthesis evolution from startrack to predict the parameters of spinning black-hole binaries observed by LIGO. The spin distribution is … Continue reading
June 29, 2018
LISA is going to be amazing: supermassive black-holes, galactic white dwarfs, EMRIs… Besides all of that, LISA can help us doing LIGO’s science better. Some LIGO sources (notably, things like GW150914) will show up in LISA years in advance. LISA … Continue reading
June 21, 2018
Gravitational-wave astronomy is moving. Quickly. In a few years we are going to have large catalogs of many detections, and a whole lot of information to extract from them. Instead of focussing on parameters (masses, spins, redshifts) of single sources, … Continue reading
June 16, 2018
Happy to report about the great success of our workshop ”Numerical Relativity beyond General Relativity”. This was organized by me, Helvi Witek, and Leo Stein at the Benasque physics center (Spain), in the beautiful region of the Pyrenees, on June … Continue reading
June 13, 2018
This is a massive review born out of the European COST Action CA16104 Gravitational waves, black holes and fundamental physics (GWverse). We summarize the status of the field of gravitational-wave astronomy and lie down a roadmap for the immediate future. Leor … Continue reading
May 4, 2018
LIGO can measure spins. Well, effective spins actually. These are special combinations of the two spins (magnitude and direction) and the binary mass ratio. There’s a ton of astrophysics that can be done just with this quantity, but one should … Continue reading
March 24, 2018
The 34th edition of the Pacific Coast Gravity Meeting, sponsored by the APS, was held at Caltech on March 16-17, 2018. This year’ edition was organized by me, Leo Stein and a few others, and was dedicated to Jim Isenberg … Continue reading
February 12, 2018
Surrogate models are fancy interpolation schemes developed to provide accurate (well, really accurate) waveforms directly from numerical relativity simulations. The first surrogate able to model fully precessing systems came up recently (and it’s really an amazing work!). Here we exploit … Continue reading
December 18, 2017
These are proceedings of the IAU Symposium 338 “Gravitational Wave Astrophysics”, held in Baton Rouge LA on October 16-19, 2017. My contribution is based on arXiv:1707.04637, where we look at the first binary black hole data using different Bayesian priors. During that … Continue reading
November 27, 2017
These are my proceedings for the 12th Edoardo Amaldi Conference on Gravitational Waves (July 9-14, 2017, Pasadena CA). I summarize how to use black-hole spin dynamics to learn about the lives of stars using gravitational-wave data. There are surprises… Before the … Continue reading
September 6, 2017
Natal kicks imparted to neutron stars and black holes at birth can be constrained using LIGO data. Kicks cause misalignments between the spins and the orbital angular momentum. Here we compare large banks of population synthesis simulations to LIGO data … Continue reading
August 11, 2017
Supernova can be used to test gravity! …and if there’s a massive scalar field around, things get terribly interesting. Here we generalize arXiv:1602.06952 to study stellar collapse in massive scalar-tensor theories of gravity (that is, the graviton is coupled to a … Continue reading
July 14, 2017
Bayesian statistics is really cool. It lets you specify clearly and openly all the assumptions that enter an analysis. What’s the effect of these prior assumptions on current inference with gravitational-wave data from black-hole binaries? Here we tackle this question … Continue reading
July 13, 2017
I was awarded the 2016 Stefano Braccini PhD Thesis Prize by the Gravitational Wave International Committee (GWIC). The prize announcement reads: Dr. Gerosa received his Ph.D. from the University of Cambridge and was nominated by his adviser, Prof. Ulrich Sperhake. Dr. Gerosa’s … Continue reading
June 21, 2017
Looks like some of the LIGO black holes have low spins (better, low effective spins). In this paper we show these values can be accommodated with standard “field binaries”, i.e. formation channels where binary black holes form from binary stars. … Continue reading
May 31, 2017
Our workshop “The disc migration issue: from protoplanets to supermassive black holes” took place in May (2017) at the Cambridge Institute of Astronomy. Chaired by Cathie Clarke and co-organized by me, Giovanni Rosotti and a few other people, we tried … Continue reading
May 5, 2017
Part of our series of spin precession papers, here we study nutational resonances. Those are configurations where the precession of L about J, and that of the two spins are in resonance with each other. These configurations are very generic … Continue reading
April 12, 2017
Black-hole data can be used to probe the lives of stars. That’s the promise of gravitational-wave astronomy, right? Here we give it a go. We present a (admittedly) very simple model showing that the misalignment of GW151226 can be easily … Continue reading
March 30, 2017
My little latex project to compile bibliographies in a smart way was published by JOSS. I really liked JOSS: it’s an innovative way to get recognition for your carefully crafted software, encouraging open science and good code practice. It’s really … Continue reading
March 18, 2017
What if the black holes LIGO sees are the results of a merger? I mean, we see mergers, but maybe those are second-generation ones, and the two merging black holes come from first-generation mergers. Or (more likely…) stellar mass black … Continue reading
December 16, 2016
Equal-mass binaries correspond to a discontinuous limit in the spin precession equations. A new constant of motion pops up, which can be exploited to study the dynamics. This is a really neat calculation done with Jakub, a Cambridge undergraduate student. Also, … Continue reading
July 30, 2016
I was interviewed by our local Cambridge TV. It was a funny experience: they asked me about black holes, gravitational waves, and black hole kicks.
June 14, 2016
Black hole kicks are cool: powerful (up to thousands of km/s!) recoils that black holes receive following a merger. Here we show these events might leave an imprint on the emitted gravitational waves, which is potentially detectable by future interferometers. … Continue reading
May 3, 2016
Here we present my numerical code precession, which implements our multi-timescale way to look at spinning black-hole binaries. The paper has a detailed description of the various functions as well as lots of examples. Update: typos in Eq. (36-37) have been … Continue reading
March 25, 2016
I was awarded a NASA Einstein Fellowship to conduct three years of postdoctoral research at Caltech. My proposal is titled “Strong gravity to the realm of observational astronomy”. Here is a passage from NASA’s press release: “We are very pleased … Continue reading
February 22, 2016
Here we present 1+1 numerical-relativity simulation of stellar collapse in scalar-tensor theories, where gravity is mediated by the usual metric coupled to an additional scalar field. Bottom line: you can test General Relativity with supernovae explosions! Davide Gerosa, Ulrich Sperhake, Christian D. … Continue reading
July 20, 2015
This is a follow up of arXiv:1403.7147, just done better. Instead of overlaps, we do real injections in LIGO parameter-estimation codes to show that spin-orbit resonances are indeed detectable. Daniele Trifirò, Richard O’Shaughnessy, Davide Gerosa, Emanuele Berti, Michael Kesden, Tyson Littenberg, Ulrich … Continue reading
July 9, 2015
I wrote a post for The Birth of an Idea, which is a really beautiful blog collecting insights on how scientists start their science. Thanks Vitor for the opportunity to contribute! Here is my post: Bikes and Colorful Pieces An … Continue reading
June 30, 2015
Here we study the stability of black-hole binaries with spins (anti)aligned with the orbital angular momentum. Aligned configurations are points of equilibrium, but are they stable? If the heavier black-hole is aligned and the lighter one is anti-aligned, this turns … Continue reading
June 10, 2015
Detailed analysis of 2PN black-hole binary spin precession using multi-timescale methods. Follow-up of the Letter arXiv:1411.0674, this paper contains the full calculation and the description of the underlying phenomenology. Davide Gerosa, Michael Kesden, Ulrich Sperhake, Emanuele Berti, Richard O’Shaughnessy.Physical Review … Continue reading
May 27, 2015
What happens if you throw a scalar field into General Relativity? And if you throw more than one? Here is a paper on the phenomenology of neutron stars in theories with more than one scalar field coupled to gravity. Michael … Continue reading
March 23, 2015
Supermassive black holes in binaries and their accretion discs… Spins align on some timescale, but migration also takes place. Do gas discs have enough time to align the spins? Well, the secret is the mass ratio: light secondaries might prevent … Continue reading
January 28, 2015
A massive review on testing gravity, which came out of a nice meeting we had at University of Mississippi in January 2014. See the numbers. Emanuele Berti, et al. (53 authors incl. Davide Gerosa).Classical and Quantum Gravity 32 (2015) 24, 243001.arXiv:1501.07274 [gr-qc].
November 3, 2014
2PN black-hole binary spin precession works exactly like Kepler’s two-body problem. Not kidding: just define effective potentials and divide the phase space into morphologies. The only things you need are a few timescales to play with. Michael Kesden, Davide Gerosa, … Continue reading
May 27, 2014
These are my proceedings of the 3rd Session of the Sant Cugat Forum on Astrophysics, held in beautiful Sant Cugat, near Barcelona on April 22-25, 2014. My contribution is this paper: have a look if you want to know more about … Continue reading
May 8, 2014
Black-hole kicks are powerful. I mean, really powerful. They can even eject supermassive black holes from the heavier galaxies in our Universe. And then these galaxies are left “empty”… Davide Gerosa, Alberto Sesana.Monthly Notices of the Royal Astronomical Society 446 (2015) … Continue reading
March 27, 2014
Spinning black-hole binaries might belong to two spin-orbit resonances, or families. Can you tell them apart using gravitational-wave observations? Spoiler: yes! Bonus note: check out the title in v1 on the arxiv… Davide Gerosa, Richard O’Shaughnessy, Michael Kesden, Emanuele Berti, … Continue reading
February 18, 2013
Spin precession in stellar-mass black hole binaries encodes information on specific formation mechanisms like tides and mass transfers. My first paper on spin precession… Davide Gerosa, Michael Kesden, Emanuele Berti, Richard O’Shaughnessy, Ulrich Sperhake.Physical Review D 87 (2013) 10, 104028.arXiv:1302.4442 … Continue reading
November 1, 2012
My very first paper was on alignment between supermassive black holes and their accretion disks. Maybe it takes a bit longer… Giuseppe Lodato, Davide Gerosa. Monthly Notices of the Royal Astronomical Society Letters 429 (2013) L30-L34.arXiv:1211.0284 [astro-ph.CO].