My paper with Marco Calzà, Davide Pedrotti, and Guan-Wen Yuan, which represents the third chapter in the primordial regular black holes saga (see this earlier news item), has now officially been published in PRD! The full bibliographic coordinates for the paper are Phys. Rev. D 112 (2025) 124015. Here is the link to the paper.
Visit by Francesca Vidotto
Today we have the pleasure of hosting Francesca Vidotto, visiting us from Madrid! Francesca is currently a senior researcher at IEM-CSIC, and is a recognized expert on (loop) quantum gravity. She will be delivering a talk by the title of “All you wanted to know about black hole remnants and never dared to ask”. Welcome Francesca!
Hawking radiation from regular black holes paper published in PRD!
My paper with Marco Calzà and Max Rinaldi, where we study Hawking radiation from regular black holes in the presence of a non-minimal scalar-curvature coupling (see this earlier news item), has now officially been published in PRD! The full bibliographic coordinates for the paper are Phys. Rev. D 112 (2025) 104055. Here is the link to the paper.
Visit by Marc Sarzi
Today we have the pleasure of hosting Marc Sarzi, visiting us from the Armagh Observatory and Planetarium. He works on extragalactic astronomy, particularly regarding integral-field spectroscopy aimed at studying the ionized gas content of nearby galaxies. He will be delivering a talk by the title of “Probing Environmental Drivers of Galaxy Evolution in the Fornax Cluster”. Welcome Marc!
Pietro Fracca's BSc defense
Congratulations to Pietro Fracca, who today successfully defended his BSc thesis, by the title of “A beginner’s introduction to the ΛCDM cosmological model” (with the opponent being Prof. Valter Moretti)! In his thesis which I supervised, Pietro reviewed and showed the effects of the 6 ΛCDM cosmological parameters on the main cosmological observables (CMB and matter power spectrum), a work far from trivial for a BSc student.
Primordial regular black holes (part 3) paper accepted in PRD!
My paper with Marco Calzà, Davide Pedrotti, and Guan-Wen Yuan, which represents the third chapter in the primordial regular black holes saga (see this earlier news item), has been accepted for publication in PRD! Compared to the earlier version there were minor changes to further discuss the cosmological and astrophysical role of PBHs, such as the regular ones (ZLMY PBHs) we study. You can read the preprint version of our paper on arXiv: 2507.02396.
Visit by Michael Zantedeschi
Today we have the pleasure of hosting Michael Zantedeschi, visiting us from the University of Pisa! Michael is currently a postdoc at the University of Pisa, and years ago was a student at the University of Trento, after which he did his PhD in Munich with Gia Dvali. He is a recognized expert on the topic of black holes, especially the memory burden effect, which he was one of the first to seriously work on. He will be delivering a talk precisely on the topic by the title of “Evaporating black holes: how the burden of their memory stabilizes them”. Welcome Michael!
Clarivate Highly Cited Researchers 2025 list
I’m beyond honored to have been included in the Clarivate Highly Cited Researchers 2025 list! Each year, this award by Clarivate recognizes those who over the past eleven years have demonstrated significant and broad influence in their fields of research, roughly including the top 0.1% of the most influential researchers. Out of 104 total researchers based in Italian institutions, this year as many as 7 researchers from the University of Trento made it into the list, which is one of the highest figures in Italy, itself rather impressive considering we are a medium-sized University: see this UniTrentoMag piece. While this award officially recognizes the impact of my research, I stress that this would not have been possible without the contribution of my outstanding collaborators, so a huge thanks to all of them, including my amazing research group in Trento!
Hawking radiation from regular black holes paper accepted in PRD!
My paper with Marco Calzà and Max Rinaldi, where we study Hawking radiation from regular black holes in the presence of a non-minimal scalar-curvature coupling (see this earlier news item), has been accepted for publication without changes in PRD! You can read the preprint version of our paper on arXiv: 2510.12257.
Solar chameleons and XENONnT
Very happy to see my latest paper with Guan-Wen Yuan, Anne Davis, Maurizio Giannotti, Luca Visinelli, and Julia Vogel out on arXiv - kudos to Guan-Wen who did all the heavy lifting! This paper is essentially a merger of two previous papers of mine: in 2021 Luca, Anne, and I argued that dark matter direct detection experiment such as XENON1T could detect chameleons, light particles potentially related to dark energy, produced in the Sun (see paper in PRD), whereas later in 2024 some of us drastically improved the model for solar chameleon production, which was previously grossly incomplete to say the least (see paper in PRD and this earlier news item). What we did here was to combine the tools built in these two papers, applying the results to newer and much more sensitive data from XENONnT, and confirming the extremely important message that terrestrial dark matter experiments are well suited to probe screened dark energy at no extra experimental cost. We clarified various previously unclear points, and derived a new upper limit on a combination of chameleon couplings (specifically the conformal coupling to photons and the disformal coupling to electrons), valid for essentially all values of the chameleon power-law index n, making it one of the most widely applicable chameleon bounds to date. You can read the results in the preprint we just posted on arXiv: 2511.01655.
Miguel Sabogal joins my group!
I’m super excited to welcome my new PhD student Miguel Sabogal to my group! Miguel, who is originally from Colombia, previously did his MSc in Brazil at the Federal University of Rio Grande do Sul under the supervision of my friend and colleague Rafael Nunes, working broadly on tests of fundamental physics from cosmological data: with me, he will keep going in this direction, with an eye in particular to cosmological tensions. Miguel already has an outstanding publication record, with several high-impact, original, and extremely interesting publications, including a PRL. Many of my colleagues I’ve spoken to think of Miguel as the potential future of cosmology in Latin America, and I am excited that he chose to join my group. Welcome Miguel!
Associate Professor
After having passed my tenure evaluation in June, today is officially my first day as (tenured) Associate Professor! Except for more money, more teaching duties, more responsibilities, and my title changing from Dr. to Prof., nothing really changes in my everyday work, which means I’ll still try to get as much research done as possible.
Hawking radiation from regular black holes
New paper with Marco Calzà and Max Rinaldi out today, making it yet one more paper 100% produced within the Theoretical Gravitation and Cosmology Group led by myself and Max! We study the issue of Hawking radiation from regular black holes (BHs): most, if not all, of the regular BH solutions usually studied are non-vacuum solutions, i.e. their Ricci scalar R is non-zero. In this case a possible non-minimal coupling of scalar fields to curvature, strongly motivated by QFT in curved space-time considerations, can become relevant, yet has almost always been ignored. What we showed is that including this non-minimal coupling can drastically alter the resulting Hawking radiation spectrum, even by orders of magnitude, leading to potentially observable effects. You can read our results in the preprint we just posted on arXiv: 2510.12257.
Marco Calzà and Davide Pedrotti are on l'Adige!
Today l’Adige, the main regional newspaper of Trentino-Alto Adige, put out in their printed version (which, I admit, I had to recover from a trash can next to a bar since I was one day late!) an extremely nice piece on Marco Calzà and Davide Pedrotti, their early years (they went to the same high school in Riva del Garda, though during different periods), how their paths crossed in Povo, and their works on black holes (the piece should be visible here). Very nice to see local newspapers giving visibility to our young researchers!
Screened dark energy and non-local quantum correlations paper published in PRD!
My paper with Fabiano Feleppa and Gaetano Lambiase, where we study non-local Bell-type quantum correlations between pairs of entangled particles within screened dark energy models (see this earlier news item), has now officially been published in PRD! The full bibliographic coordinates for the paper are Phys. Rev. D 112 (2025) 084011. Here is the link to the paper.
BAO and the Hubble tension no-go theorem
I’m extremely excited to finally see my latest paper with Davide Pedrotti, Luis Escamilla, Valerio Marra, and Leandros Perivolaropoulos, finally out on the arXiv - kudos to Davide who did all the heavy-lifting in what I do not hesitate to place among the three most important papers I ever wrote! This paper is about what we could call the “Hubble tension no-go theorem”, which forbids purely post-recombination solutions due to the constraints BAO impose on the product of the sound horizon and the Hubble constant. However, the pipeline from which BAO measurements are obtained requires assuming a fiducial cosmological model, with the choice falling on ΛCDM: many have therefore wondered whether we can trust these measurements when testing late-time modifications to ΛCDM, and this is the most frequently invoked loophole to the no-go theorem. In this work we have played devil’s advocate and showed that, even if BAO measurements were to be grossly (and unrealistically) biased by fiducial cosmology assumptions, this would still not be sufficient to rescue post-recombination solutions to the Hubble tension, primarily because of the extremely tight constraints on the (unnormalized) shape of the expansion history from unanchored SNeIa, whose role in the Hubble tension so far has been underappreciated. You can read our results in the preprint we just posted on arXiv: 2510.01974.
Visit by Zakaria Belkhadria
For the next week and a half we have Zakaria Belkhadria, who recently received his PhD from the University of Cagliari and the University of Geneva, visiting us funded by a CosmoVerse COST STSM grant. He will be working with me and Max Rinaldi on the complementarity between strong-field and cosmological tests of modified gravity. Welcome Zakaria!
Visit by Alex Ganz
For the next three days we have Alex Ganz visiting us from the University of Hannover! Alex is currently a postdoc in the group of Guillem Domènech, and has worked on several topics of interest to our group, such as modified gravity (including mimetic gravity) and gravitational waves. He will be delivering a talk by the title of “Exploring modified gravity theories”. Welcome Alex!
Top 2% scientists (2024 edition)
As with last year, for what it’s worth, it looks like my name appeared in the list of top 2% scientists worldwide, compiled by John Ioannidis at Stanford University, and available here. It seems that for the year 2024 I’ve been ranked 1546th across all fields, and 14th in my area (again looks quite high, perhaps it’s because some Scopus research evaluation tool thinks my main area is Nuclear & Particle Physics rather than Astronomy & Astrophysics), whereas considering my whole career the numbers become 43884th and 749th respectively. Again, all the caveats highlighted previously apply.
Giada Daldoss' BSc thesis defense
Congratulations to Giada Daldoss, who today successfully defended her BSc thesis (for the BSc degree in Mathematics), by the title of “Nozioni di base di Relatività Generale con applicazioni al problema dell’Energia Oscura”, which translates to “Basic notions of General Relativity with applications to the Dark Energy problem” (with the opponent being Prof. Valter Moretti)! In her thesis which I supervised, Giada introduced basic concepts of General Relativity, before discussing the most important observational indications of Dark Energy.
