Conveners
06 - Early universe
- Daniel G. Figueroa (CERN)
06 - Early universe
- Daniel G. Figueroa (CERN)
-
Craig Hogan (U. Chicago and Fermilab)05/12/2015, 14:00TalkIt is proposed that small amplitude, coherent rotational fluctuations arise from the emergence of nearly-classical non-rotating inertial frames from Planck scale quantum elements. An exact form is calculated for Planck scale correlations in the signal of a Sagnac type interferometer, where the light path encloses a large area of arbitrary shape, normalized using area quantization from...Go to contribution page
-
Dr. Bikash Chandra PAUL (University of North Bengal)05/12/2015, 14:21TalkEmergent universe (EU) scenarios describe the evolution of a static Einstein universe in the infinite past whereby certain problems associated with the big-bang singularity can be circumvented. A flat universe composed of interacting fluids with a non-linear equation of state within the EU scenario leads to a viable cosmological model accommodating the presently observed accelerating era, as...Go to contribution page
-
Dragan Hajdukovic (Institute of Physics, Astrophysics and Cosmology)05/12/2015, 14:42TalkIt was recently suggested that what we call dark matter and dark energy, can be explained as the local and global effects of the gravitational polarization of the quantum vacuum by the immersed Standard Model matter. This result appears as the consequence of the working hypothesis that by their nature quantum vacuum fluctuations are virtual gravitational dipoles. Here, we argue that, as a...Go to contribution page
-
Jonathan Braden (University College London)05/12/2015, 15:03TalkFirst-order phase transitions proceed through the nucleation and subsequent collision of bubbles. In false vacuum eternal inflation, such collision events are ubiquitous and provide a possible avenue to observationally test the multiverse. They also play an important role in early high temperature phase transitions. I will present results for the full three-dimensional nonlinear dynamics...Go to contribution page
-
Lavinia Heisenberg (ETHZ - ETH Zurich)05/12/2015, 15:24TalkIn order to regularize the energy of point-like charged particles, Born and Infeld introduced a modification of the Maxwell lagrangian that naturally imposes an upper bound on electromagnetic fields. This approach was later taken by Deser and Gibbons to propose an analogous modification for gravity. I will review these ideas and discuss a scenario where inflation could be supported by a set of...Go to contribution page
-
Andrey Shkerin (EPFL)05/12/2015, 16:15TalkWe study Coleman – De Luccia tunneling of the Standard Model Higgs field during inflation in the case when the electroweak vacuum is metastable. We verify that the tunneling rate is exponentially suppressed. The main contribution to the suppression is the same as in flat space-time. We analytically estimate the corrections due to the expansion of the universe and an effective mass term in...Go to contribution page
-
Dr Daniel G. Figueroa (CERN)05/12/2015, 16:35TalkI will present the cosmological implications of the decay of the Standard Model Higgs after Inflation, when assuming a post-inflationary/pre-BBN expansion history driven by a stiff source with equation of state w > 1/3. In particular, I will discuss first the realisation of a successful 'reheating' mechanism, and secondly, the production of a large background of gravitational waves by the...Go to contribution page
-
Francesco Cefalà (University of Basel)05/12/2015, 16:55TalkI will first give a short overview of preheating after hilltop inflation. In the main part of the talk I will discuss how the dynamics can change when the inflaton couples to another scalar field, e.g. a right-handed sneutrino, which provides a mechanism for generating the correct initial conditions for inflation and also a decay channel for the inflaton that allows for non-thermal...Go to contribution page
-
Stefano Orani (Basel University)05/12/2015, 17:15TalkDuring hilltop inflation, the inflaton rolls away from the maximum of its potential and towards the minimum where the universe reheats. The first stage of reheating, preheating, is non-perturbative and, in this model, localized oscillating bubbles of the inflaton field, called oscillons, are formed. Furthermore, when other fields are present, they can be produced via a parametric resonance...Go to contribution page
-
Roland de Putter05/12/2015, 17:35TalkThe large-scale distribution of galaxies is a powerful probe of the physics of Inflation. In this talk, I will explain what it would take for a future galaxy survey to use galaxies as a probe of primordial non-Gaussianity in order to distinguish between single-field and multi-field Inflation, and I will introduce a specific proposal for such a survey, called SPHEREx. I will also revisit the...Go to contribution page
-
Subodh Patil05/12/2015, 17:55TalkAt any given energy, gravitational interactions have a strength set by a characteristic scale $M_*$, inferred from amplitudes calculated in an effective theory with a strong coupling scale $M_{**}$. These are in general different from each other and $M_{\rm pl}$, the macroscopic strength of gravity as determined by (laboratory scale) Cavendish experiments. We explore several consequences of...Go to contribution page
-
Christian Byrnes (University of Sussex (GB))05/12/2015, 18:15TalkIt is both remarkable, and disappointing, that only two parameters describing the primordial perturbations can explain the statistical properties of millions of CMB temperature perturbations. However, the persistence of several large-scale cosmological anomalies in WMAP and Planck satellite data may provide a clue to new physics. I will discuss how inflationary models can explain the observed...Go to contribution page