Thu 22 Jan 11:00: Yarong Liu on "Crawling into the Future: How early animal movement disturbed the seafloor and reshaped marine ecosystems"
In person
- Speaker: Yarong Liu (Cambridge Zoology)
- Thursday 22 January 2026, 11:00-12:00
- Venue: Thirkill Room, Old Court, Clare College.
- Series: LCLU Coffee Meetings; organiser: Paul B. Rimmer.
Fri 23 Jan 13:00: Black-hole METRICS, ringdown and fundamental physics
Most gravitational-wave signals detected by the LIGO –Virgo–KAGRA network originate from binary black-hole coalescences. The newly formed black hole is highly distorted immediately after the merger and gradually settles into a stationary state by emitting gravitational waves. These waves exhibit a discrete set of exponentially decaying frequencies known as quasinormal modes. The corresponding phase, called the ringdown, encodes the unique fingerprint of the final black hole. Analyzing quasinormal modes provides a powerful avenue to probe fundamental physics, including stringent tests of general relativity in the strong-field regime. However, obtaining the quasinormal-mode spectrum of generic black holes presents severe mathematical challenges, as it requires solving a complex system of coupled partial differential equations. In this talk, I will introduce METRICS , Metric pErTuRbations wIth speCtral methodS, a spectral formalism that overcomes these difficulties and enables precise computation of quasinormal-mode spectra for general black holes. I will demonstrate how METRICS can be applied to a range of modified gravity theories motivated by high-energy physics, including axi-dilaton, dynamical Chern-Simons, and Einstein-scalar-Gauss-Bonnet theories, to conduct ringdown-only tests of gravity. These analyses yield, among other results, the first observational constraints on axi-dilaton gravity. If time permits, I will mention the results of the recent first accurate construction of nearly extremal black holes in modified gravity theories. I will conclude by outlining future applications of METRICS for extracting new insights into fundamental physics through black-hole ringdowns.
- Speaker: Adrian Ka-Wai Chung, DAMTP
- Friday 23 January 2026, 13:00-14:00
- Venue: Potter Room / Zoom : https://cam-ac-uk.zoom.us/j/85131795570.
- Series: DAMTP Friday GR Seminar; organiser: Lorenzo Gavassino.
Mon 02 Mar 16:00: TBD
TBD
- Speaker: Ben Snow (Exeter)
- Monday 02 March 2026, 16:00-17:00
- Venue: MR14 DAMTP and online.
- Series: DAMTP Astrophysics Seminars; organiser: Loren E. Held.
Tue 03 Feb 11:15: Title TBC
Abstract TBC
- Speaker: Skyla White (Cavendish Astrophysics)
- Tuesday 03 February 2026, 11:15-12:00
- Venue: Coffee area, Battcock Centre.
- Series: Hills Coffee Talks; organiser: Charles Walker.
Thu 22 Jan 16:00: What is going on with large-scale structure cosmology?
The way matter is distributed on large scales is strongly sensitive to many key questions cosmologists have about the Universe, including what are the natures of dark matter and dark energy, what were the initial conditions of the Universe, and is gravity adequately described by General Relativity on all scales? The quantity, quality, and variety of observations of large-scale structure is presently undergoing a revolution, allowing us to test the standard model of cosmology and its possible extensions to levels of accuracy not previously possible. So far, a mixed picture is emerging where some tests appear perfectly consistent with the standard model while others show varying levels of tension. Key in this discussion are the theoretical predictions used to interpret the observational measurements in terms of cosmology. In this talk, I will summarise some of the current findings and discuss important systematic uncertainties on the theoretical modelling side. I will then discuss some avenues for future progress required to maximise the cosmological constraining power of forthcoming Stage IV surveys.
- Speaker: Ian McCarthy
- Thursday 22 January 2026, 16:00-17:00
- Venue: Hoyle Lecture Theatre, Institute of Astronomy.
- Series: Institute of Astronomy Colloquia; organiser: Dr Anik Halder.
Thu 22 Jan 11:00: Yarong Liu, topic TBD
In person
- Speaker: Yarong Liu (Cambridge Zoology)
- Thursday 22 January 2026, 11:00-12:00
- Venue: Thirkill Room, Old Court, Clare College.
- Series: LCLU Coffee Meetings; organiser: Paul B. Rimmer.
Thu 15 Jan 11:00: Edouard Barrier on Origins of Life on Deep Ocean Worlds
In person
- Speaker: Edouard Barrier (IoA, Cambridge)
- Thursday 15 January 2026, 11:00-12:00
- Venue: Battcock, Room F17.
- Series: LCLU Coffee Meetings; organiser: Paul B. Rimmer.
Wed 28 Jan 13:15: Lighting up a new Standard Candle: calibration of AGNs
Exploring new/alternative standard candles is crucial for advancing cosmology. One spanning a wide redshift range, like quasars (QSOs), can provide orthogonal constraints on model parameters, among which H0, with its current tension, is particularly relevant. The 2 keV to 2500 Å flux ratio in QSOs shows great potential as a cosmological tool (e.g., Lusso+20, Sacchi+22) if suitable subsets are identified, akin to the corrections applied to supernovae. We investigate various properties of QSOs to deepen our understanding of QSO physics and refine the selection criteria for a new cosmological quasar sample. We specifically examine the most luminous QSOs exhibiting strong outflows in the C IV emission line to clarify the relation between the strength of the outflows and X-ray emission, thereby enhancing our understanding of the mechanisms within active galactic nuclei (AGN) engines. Using targeted observations with Chandra, we determine the slope of the 2 keV to 2500 Å luminosity relation and explore how the C IV blueshift correlates with the steepness of the UV-to-X-ray spectral energy distribution. To gain insights into the fundamental processes underlying the 2 keV to 2500 Å luminosity relation, we analyse the slopes of the relation measured using multi-epoch XMM observations of specific sources. Finally, to investigate the correlations between the dispersion of the 2 keV to 2500 Å luminosity relation, fundamental AGN properties, and optical variability, we assess several variability features from the ZTF optical light curves and conduct a dimension reduction analysis.
- Speaker: Anastasia Shlentsova / Pontificia Universidad Católica de Chile
- Wednesday 28 January 2026, 13:15-13:40
- Venue: Hoyle Lecture theatre + Zoom .
- Series: Institute of Astronomy Seminars; organiser: Xander Byrne.
Thu 12 Feb 16:00: HiPERCAM: high time-resolution astrophysics
One of the best ways of studying compact objects in the Universe, such as white dwarfs, neutron stars, black holes and objects in our Solar System, is through their brightness variations. These tend to occur on timescales of seconds and below, and hence requires specialised astronomical instrumentation. In this talk, I shall review the design and scientific highlights of the high-speed camera HiPERCAM, which is now permanently mounted on the world’s largest optical telescope – the 10.4m GTC on La Palma.
- Speaker: Vikram S Dhillon
- Thursday 12 February 2026, 16:00-17:00
- Venue: Hoyle Lecture Theatre, Institute of Astronomy.
- Series: Institute of Astronomy Colloquia; organiser: Jan Scholtz.
Mon 19 Jan 13:00: Exploring the Universe with Line-Intensity Mapping
Line-Intensity mapping (LIM) uses the integrated flux along the line of sight as tracer of the LSS . Using relatively low-aperture telescopes, it recovers radial information targeting known spectral lines discarding the continuum emission, which makes the experiments cheaper compared with galaxy surveys. Mapping the intensity fluctuations of an array of lines from HI 21cm to optical-UV lines offers a unique opportunity to probe redshifts well beyond the reach of other cosmological observations, access regimes that cannot be explored other- wise, and exploit the enormous potential of cross-correlations with other measurements. This promises to deepen our understanding of various questions related to galaxy formation and evolution, cosmology, and fundamental physics. In this talk I will cover the current status of LIM , main measurements and the promised potential for the future, with focus on the next steps that must be taken to bring this technique to full speed for precision cosmology.
- Speaker: José Luis Bernal (Instituto de Física de Cantabria)
- Monday 19 January 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 26 Jan 13:00: The Cosmic Neutrino Background
“The cosmic neutrino background is like the cosmic microwave back- ground, but less photon-y and more neutrino-ey. The CNB is also less talked about than the CMB , mostly because it’s nearly impossible to detect directly. But if it could be detected, it would be interesting in several ways that are discussed.”
- Speaker: Douglas Scott (University of British Columbia)
- Monday 26 January 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Louis Legrand.
Mon 16 Mar 13:00: Title to be confirmed
Abstract not available
- Speaker: Maciej Bilicki (Warsaw, CFT)
- Monday 16 March 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 09 Mar 13:00: Title to be confirmed
Abstract not available
- Speaker: Simone Blasi (DESY)
- Monday 09 March 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 02 Mar 13:00: Title to be confirmed
Abstract not available
- Speaker: Diego Blas (IFAE Barcelona)
- Monday 02 March 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 23 Feb 13:00: Title to be confirmed
Abstract not available
- Speaker: Ana Achúcarro (Leiden U.)
- Monday 23 February 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 16 Feb 13:00: Title to be confirmed
Abstract not available
- Speaker: Ruth Durrer (University of Geneva)
- Monday 16 February 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 09 Feb 13:00: Title to be confirmed
Abstract not available
- Speaker: Elsa Teixeira (Montpellier U.)
- Monday 09 February 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 02 Feb 13:00: Title to be confirmed
Abstract not available
- Speaker: Mariana Carrillo (Imperial College)
- Monday 02 February 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Mon 19 Jan 13:00: Title to be confirmed
Abstract not available
- Speaker: José Luis Bernal (Instituto de Física de Cantabria)
- Monday 19 January 2026, 13:00-14:00
- Venue: CMS, Pav. B, CTC Common Room (B1.19) [Potter Room].
- Series: Cosmology Lunch; organiser: Gonzalo Villa.
Thu 05 Feb 16:00: Gravitational wave and electromagnetic signatures of binary black holes with circumbinary gas
Binary black holes (BHBs) embedded in dense gas hold the promise of so-called “multi-messenger astrophysics”: when they are detected both through gravitational waves (GWs) and electromagnetic (EM) observations, they will enable novel science. This is true both for massive BHBs, whose GWs will be detectable by the future LISA satellite and by on-going pulsar timing arrays (PTAs), as well as for stellar-mass BHBs detected through ground-based GW detectors. In both cases, identifying the coalescing binaries through their EM signatures will help clarify their astrophysical origin and yield novel probes of cosmology, fundamental physics, and accretion physics. In this talk, I will describe how circumbinary gas may produce characteristic EM signatures for both massive and stellar-mass BHBs, based on analytic models as well as hydrodynamical simulations. I will also argue that in both cases, some coalescing binaries may have already been detected in optical surveys, providing clues about their origin.
- Speaker: Zoltan Haiman
- Thursday 05 February 2026, 16:00-17:00
- Venue: Hoyle Lecture Theatre, Institute of Astronomy.
- Series: Institute of Astronomy Colloquia; organiser: Jan Scholtz.