SEMINAR:Locality and Accelerated Expansion

Guest: Gizem Şengör, Boğaziçi University

Title: Locality and Accelerated Expansion

Date/Time: 21 May 2025, 13:40

Location: FENS G032

Abstract: Quantized fields on flat spacetime are expected to exhibit locality. Locality on flat space can be studied in terms of cluster decomposition principle which is a statement on the factorization properties of Smatrix.  While observations on flat spacetime can be expressed in terms of scattering aplitudes this framework completely changes for cosmological spacetimes. One cosmological case of particular interest in the history of our universe is that of accelerated expansion, idealized as de Sitter spacetime. In this talk we will discuss the notion of locality on de Sitter guided by the symmetries of de Sitter spacetime.

Bio: Gizem Şengör obtained both of her BSc. And MSc. degrees from Boğaziçi University, Physics department in 2011 and 2013 respectively. She obtained her PhD. degree from Syracuse University, Physics department in 2018 with a thesis titled "Cosmological Perturbations in the Early Universe". In 2019 she joined CEICO (Central European Institute of Cosmology and Fundamental Physics) which is a young and prospering institute under the Czech Academy of Sciences, Institute of Physics in Prague. She was a Marie Curie Fellow at CEICO with the project SYMACC: SYMmetries and degrees of freedom in ACCelerated epochs of expansion and initiated the All Lambda Holography Workshops, on going since 2021. From there on, she joined Boğaziçi University Physics Department as Assistant Professor in June 2022. Her research follows different themes in cosmology anchored around the presence of symmetries and their consequences, that have overlaps with quantum field theory and holography.