Cosmological Observables: Cambridge-LMU Cosmology Meeting

Sitzung

Early Universe

30.09.2026, 14:10

Centre for Mathematical Sciences

122. Alex Jenkins - "Toward a real-time theory of vacuum decay"

30.09.26, 14:10

False vacuum decay plays a pivotal role in the physics of the early Universe. However, we lack a satisfying theoretical understanding of this process, with existing approaches working only in imaginary (Euclidean) time, and relying on untested assumptions and approximations. In this talk, I will introduce two complementary approaches toward a real-time theory of vacuum decay: semiclassical...

123. Matthias Nowinski - "Inflationary Bispectra and IR Physics from Quantum Simulators"

30.09.26, 14:30

Bose-Einstein condensates have been used successfully as quantum simulators for early-universe particle production. We extend this analogy to the interacting theory. To this end, we compute the leading interaction terms expected in a general experimental setup that determine the 3-point correlations. We apply them to cosmologically motivated expanding model universes, but also periodically...

124. Guanming Liang

30.09.26, 14:45

Inflation offers a compelling explanation of how the primordial universe evolved into the universe well described by $\Lambda$CDM. Measuring the non-Gaussianity of primordial density fluctuations will deliver crucial insight into the more fundamental mechanism behind inflation. We forecast future constraints on local primordial non-Gaussianity ($f_{\rm NL}^{\rm loc}$) under the context of...

125. Lasse Gerblich - "Gravitational and Axion Radiation from thin Cosmic Strings"

30.09.26, 15:00

Cosmic strings are one-dimensional topological defects that may form in symmetry-breaking phase transitions in the early universe. While they may reach cosmological scales in length they are typically thinner than a proton. Therefore we can treat them as essentially one-dimensional when modelling their dynamics.
If they exist we may detect them through the radiation they emit: If they form in...

127. Bowei Zhang

30.09.26, 15:15

Dissipative effects appear in many early-Universe scenarios, yet their universal observational signatures and systematic confrontation with data remain largely unexplored. We employ the Open Effective Field Theory of Inflation (Open EFToI) to consistently incorporate dissipative and stochastic effects while preserving scale invariance. Dissipation enhances specific interaction channels of the...

126. Siva Pawan Venna - "Dressing rules and Spectral representation for cosmological correlators"

Recent developments in computing cosmological dressing rules have produced different formalism to compute the correlator and thus aid study of their properties. Dressing rules [2503.10598] and the spectral representation (KLF) are two such recent results being used to compute correlators. Dressing rules were derived as a way to add additional propagators to use the flat space feynman rules to...