Institute of Astronomy

Dr Sunny Vagnozzi


My research interests lie broadly at the intersection of cosmology, astrophysics, and particle physics. I work at the interface of  data analysis, theory, phenomenology, and experiments. My goal, through precision cosmological and astrophysical data, is: to identify those models which best describe our Universe, and in particular its dark components - dark matter (DM) and dark energy (DE); to constrain the parameters of these models and define goals for future experiments; and likewise to construct viable data-driven theoretical models. This back-and-forth interplay between existing data, future experiments, and theory, represents my main research strength.

Data-wise my primary focus is on Cosmic Microwave Background (CMB) and large-scale structure (LSS) data. I am interested in how combinations and/or cross-correlations between CMB and LSS can fully bring into play the synergy between these two probes. I am a member of the Simons Observatory collaboration, which will provide exquisitely accurate maps of the CMB sky from the Atacama Desert. I have recently begun exploring new windows onto fundamental physics, including future gravitational wave experiments and images of black hole shadows.

A significant part of my data-driven interests has been neutrino cosmology, particularly how to extract information on neutrino masses and their mass ordering in a robust way, and reduce systematics (for instance related to galaxy bias) which might limit our understanding of neutrino properties. Other aspects of fundamental physics I have worked towards probing include inflationary models, DE models, interactions between DE and DM, unified dark sector models, extra dimensions, axions, modifications to General Relativity (GR), and possible observable manifestations of string theory such as the string axiverse, AdS vacua, and astrophysical violations of the Kerr bound.

Theory-wise my focus is on models of DM, DE, and cosmic inflation. My main interests in these directions have been related to constructing alternative models for the dark components of our Universe which address some of the most important shortcomings of the standard ΛCDM paradigm on both cosmological and astrophysical scales. Examples include models with strong DM self-interactions, interactions between DM and DE, or modifications to GR. At the same time, I have worked on predicting signatures of such models in cosmological as well as astrophysical observations, and DM experiments.

I joined the University of Cambridge in October 2019 as a Newton-Kavli Fellow within the Kavli Institute for Cosmology (KICC) and the Institute of Astronomy (IoA), jointly funded by the Kavli Foundation and the Isaac Newton Trust. I am also affiliated to the Department of Applied Mathematics and Theoretical Physics (DAMTP) and am a research associate at Homerton College. Earlier in 2019 I earned my PhD in Theoretical Physics at Stockholm University (you can read my thesis here), where my primary advisor was Prof. Katherine Freese.

Selected papers

10 main representative publications (for full list of publications and preprints with bibliometric details see my INSPIRE profile, my ADS profile, and my Google Scholar profile):


Oct 2019 - present: Newton-Kavli Fellow at the Kavli Institute for Cosmology (KICC), Institute of Astronomy (IoA) and Department of Applied Mathematics and Theoretical Physics (DAMTP), University of Cambridge

Oct 2019 - present: Research associate at Homerton College, Cambridge

Sep 2015 - Sep 2019: PhD in Theoretical Physics and research assistant at the Oskar Klein Centre for Cosmoparticle Physics (OKC), Stockholm University (advisors: Prof. Katherine Freese and Prof. Lars Bergström)

Jan 2015 - Aug 2015: Long-term research visit at the Niels Bohr Institute (NBI), University of Copenhagen (advisor: Prof. Subir Sarkar)

Mar 2013 - Dec 2014: MSc in Physics at the University of Melbourne and the ARC Centre of Excellence for Particle Physics at the Terascale (advisors: Dr. Robert Foot and Prof. Raymond Volkas)

Sep 2012 - Feb 2013: Erasmus exchange at Imperial College London

Sep 2009 - Jul 2012: BSc in Physics at the University of Trento (advisor: Prof. Valter Moretti)

Sep 2009: Violin Diploma (equivalent to BA) at Santa Cecilia Conservatory, Rome


2019: PhD in Theoretical Physics, Stockholm University

2014: MSc in Physics, University of Melbourne

2012: BSc in Physics, University of Trento

2009: Violin Diploma (equivalent to BA), Santa Cecilia Conservatory

Awards and Prizes

Selected awards and prizes:

  • Symmetry 2020 Young Investigator Award (2021)
  • Springer Thesis Award, Springer Nature (2020)
  • "Pio Picchi" Prize, Italian Physical Society (2019)
  • Newton-Kavli Fellowship Kavli Institute for Cosmology, University of Cambridge (2019)
  • Chamberlain Fellowship, Lawrence Berkeley National Laboratory and UC Berkeley (2019, declined)
  • CITA Fellowship, Canadian Institute for Theoretical Astrophysics, University of Toronto (2018, declined)
  • Chancellors' Fellowship, University of CaliforniaIrvine (2015, declined)
  • Regents' Fellowship, University of CaliforniaSanta Cruz (2015, declined)
  • Dean's Honours List, University of Melbourne (2015)
  • Huygens Fellowship, Leiden University (2015, declined)


See my INSPIREADS, and Google Scholar profiles for a complete list of publications and preprints with bibliometric details (of the three, INSPIRE is more accurate and complete)

Other Professional Activities

Peer review is an integral part of my professional activity. I believe in the value and importance of timely and quality peer review, and am always eager to perform peer reviewing activity. I have reviewed for most of the main journals in the fields of cosmology, astrophysics, and high-energy physics, including Nat. Astron., PRL, PRD, PLB, MNRAS, JCAP, CQG, PDU, EPJC, was one of the recipients of the Global Peer Review Awards for 2018-2019 (Award Category: Physics). I also received a 2019 IOP Publishing Outstanding Reviewer Award for Classical and Quantum Gravity. Please see my Publons profile for more details on my reviewing activity.

I serve on the Editorial Boards of Advances in High Energy PhysicsExperimental Results, and Universe (MDPI). Experimental Results is an innovative journal recently launched by Cambridge University Press to tackle the growing crisis in reproducibility of results (see the official press release here). I am also serving as lead Guest Editor for the Special Issue "Dark Matter and Dark Energy: Particle Physics, Cosmology, and Experimental Searches" of the journal Universe (MDPI).

Press Coverage and Media Appearance

My work has been covered in various popular science (and not) magazines, global news websites, and blogs. Below are links to the main articles covering my work:

Page last updated: 25 February 2022 at 14:00