Professor Seshadri Nadathur
Summary
I am Professor of Cosmology at the Institute of Cosmology and Gravitation. My research area is observational cosmology – this means I study the properties of dark energy, dark matter and gravity, using the large-scale structure of the Universe and based on galaxy survey data collected by the leading ground-based and space telescopes.
My research has been funded by the Science and Technology Facilities Council (STFC), the UK Space Agency (UKSA), and the European Commission.
Research interests
I study the large-scale structure of the Universe, analysing the statistical patterns in the distribution of millions of galaxies to uncover cosmological information. I am particularly known for my work on baryon acoustic oscillations and the development of new methods beyond two-point clustering statistics, such as cosmic voids or density-split statistics. More generally I have worked on a wide range of other areas in cosmology, including redshift-space distortions, clustering of the Lyman-alpha forest and gravitational lensing, as well as theoretical models of dark matter, dark energy and inflation.
A large fraction of my work involves the Dark Energy Spectroscopic Instrument survey, or DESI. DESI is a 8-year spectroscopic survey programme to map the positions of 60 million galaxies and quasars in order to determine the dark energy equation of state, the neutrino mass scale, and a host of other science results. I led the Galaxy and Quasar Clustering working group in DESI from 2022-2025, when we published our major results from the first two data releases.
Another large part of my work is within the Euclid Consortium. Euclid is a space telescope, which combines spectroscopic measurements of around 30 million galaxies with weak lensing and photometric surveys of over a billion. I lead a UKSA-funded group at Portsmouth creating the spectroscopic galaxy catalogues and visibility mask for Euclid clustering science, and coordinate a DR1 Key Project on measuring baryon acoustic oscillations.
In the past I also worked on the extended Baryon Oscillation Spectroscopic Survey (eBOSS) and the Dark Energy Survey (DES).
Media availability
I am available for media requests, interviews and comments on astronomy- and cosmology-related stories. My previous contributions include appearances on The Sky At Night, a BBC4 documentary with Hannah Fry, and interviews for national and international media outlets.
I also give public lectures about cosmology in science festivals and meetings in the local area.
Research outputs
2026
Euclid preparation: CIII. Constraining parameterised models of modifications of gravity with the spectroscopic and photometric primary probes
Collaboration, E., Albuquerque, I. S., Frusciante, N., Sakr, Z., Srinivasan, S., Atayde, L., Bose, B., Cardone, V. F., Casas, S., Martinelli, M., Noller, J., Teixeira, E. M., Thomas, D. B., Tutusaus, I.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 21p., A214
Research output: Article
Euclid preparation: XCIX. Cosmology Likelihood for Observables in Euclid (CLOE). 6: Impact of systematic uncertainties on the cosmological analysis
Collaboration, E., Blot, L., Tanidis, K., Cañas-Herrera, G., Carrilho, P., Bonici, M., Camera, S., Cardone, V. F., Casas, S., Davini, S., Domizio, S. D., Farrens, S., Goh, L. W. K., Beauchamps, S. G.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 22p., A191
Research output: Article
Euclid preparation: XCV. Cosmology Likelihood for Observables in Euclid (CLOE). 2. Code implementation
Collaboration, E., Joudaki, S., Pettorino, V., Blot, L., Bonici, M., Camera, S., Cañas-Herrera, G., Cardone, V. F., Carrilho, P., Casas, S., Davini, S., Domizio, S. D., Farrens, S., Goh, L. W. K., Beauchamps, S. G.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 42p., A187
Research output: Article
Euclid preparation: XCVII. Cosmology Likelihood for Observables in Euclid (CLOE). 4: Validation and Performance
Collaboration, E., Martinelli, M., Pezzotta, A., Sciotti, D., Blot, L., Bonici, M., Camera, S., Cañas-Herrera, G., Cardone, V. F., Carrilho, P., Casas, S., Davini, S., Domizio, S. D., Farrens, S., Goh, L. W. K.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 18p., A189
Research output: Article
Euclid preparation: XCVI. Cosmology Likelihood for Observables in Euclid (CLOE). 3. Inference and Forecasts
Collaboration, E., Cañas-Herrera, G., Goh, L. W. K., Blot, L., Bonici, M., Camera, S., Cardone, V. F., Carrilho, P., Casas, S., Davini, S., Domizio, S. D., Farrens, S., Beauchamps, S. G., Ilić, S., Joudaki, S.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 38p., A188
Research output: Article
Euclid preparation: XCVIII. Cosmology Likelihood for Observables in Euclid (CLOE). 5. Extensions beyond the standard modelling of theoretical probes and systematic effects
Collaboration, E., Goh, L. W. K., Nouri-Zonoz, A., Pamuk, S., Ballardini, M., Bose, B., Cañas-Herrera, G., Casas, S., Franco-Abellán, G., Ilić, S., Keil, F., Kunz, M., Brun, A. M. C. L., Lepori, F., Martinelli, M.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 23p., A190
Research output: Article
Euclid preparation: CII. Non-Gaussianity of 2-pt statistics likelihood: Parameter inference with a non-Gaussian likelihood in Fourier and configuration space
Collaboration, E., Beauchamps, S. G., Bel, J., Baratta, P., Carbone, C., Altieri, B., Andreon, S., Auricchio, N., Baccigalupi, C., Baldi, M., Bardelli, S., Battaglia, P., Bernardeau, F., Biviano, A.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 25p., A213
Research output: Article
Beyond traditional emission-line diagnostics: using autoencoders to uncover active galactic nuclei in DESI spectra
Alcolea, J. A., Siudek, M., Eriksen, M., Mezcua, M., Pucha, R., Juneau, S., Gontcho, S. G. A., Panda, S., Aguilar, J., Ahlen, S., Bianchi, D., Brodzeller, A., Brooks, D., Castander, F. J., Claybaugh, T.,
21 Sep 2026, In: Astronomy and Astrophysics. 713, 19p., A133
Research output: Article
Euclid: IX. Galaxy SED reconstruction in the PHZ processing function: impact on the PSF and the role of medium-band filters
Collaboration, E., Tarsitano, F., Schreiber, C., Miyatake, H., Nishizawa, A. J., Hartley, W. G., Miller, L., Cragg, C., Csizi, B., Hildebrandt, H., Altieri, B., Amara, A., Andreon, S., Auricchio, N.,
16 Sep 2026, In: Astronomy and Astrophysics. 713, 17p., A178
Research output: Article
The power of DESI for photometric redshift calibration: a case study with KiDS-1000
Blanco, D., Leauthaud, A., Lange, J. U., Wright, A. H., Hildebrandt, H., Heydenreich, S., Ravulapalli, D., Ratajczak, J., Dawson, K. S., McCullough, J., Dey, B., Aguilar, J. N., Ahlen, S., Anand, A.,
14 Sep 2026, In: Open Journal of Astrophysics. 9, 21p.
Research output: Article