ELFT HÍRADÓ

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ELTE Fizikai Intézet

                                ORTVAY KOLLOKVIUM

                    2019. május 9., csütörtök, 15:00-kor
                Az ELTE Pázmány Péter s. 1/A alatti épületében
                           földszinti 0.81 előadóban


                            Christof Wetterich
        (Institut für Theoretische Physik Universität Heidelberg)

        Quantum gravity predictions for particle physics and cosmology


Kivonatos ismertetés:
Contrary to general belief, quantum gravity can have important consequences 
for
observations in present day experiments. It can predict parameters of the 
standard model. Functional renormalisation permits the computation of 
fluctuation effects of the metric. Quantum gravity can be formulated as a 
non-perturbatively renormalisable quantum field theory, in close analogy to 
the other fundamental interactions. The scale symmetry associated to the 
ultraviolet fixed point has far reaching implications for particle physics 
and cosmology.

Quantum fluctuations of the metric determine important parameters of the 
Higgs-potential at an energy scale close to the Planck mass. Extrapolating the 
running couplings to the electroweak scale, the mass of the Higgs boson has 
been predicted in the range found later by experiment. I discuss further 
possible predictions for particle physics, in particular the gauge hierarchy 
between the Planck scale and the Fermi scale.

In cosmology, the approximate scale symmetry of the primordial fluctuation 
spectrum, which seeds the CMB anisotropies and all structures in the Universe, 
is explained by the vicinity of an ultraviolet fixed point. The scalar field 
mediating dynamical dark energy arises from spontaneous scale symmetry breaking
near an infrared fixed point.