Calendar

Speaker: Salvatore Sciortino (INAF)

Titolo: “Is Quantum Mechanics the last word ? Why not ? Some alternative ideas  toward (re-)introducing realism in Physics”

Abstract:

The General Relativity (GR) and Quantum Mechanics (QM) are the two pillars of
today Physics. They have been verified in a huge number of conditions and have
survived to all falsification attempts. Several key aspects of our life and our
societies are based on them, among them the entire internet “world”, mobile
phones and GPS assisted navigation. Despite these astonishing successes, after
about 100 years of efforts of the smartest worldwide physicists GR and QM still
remain essentially incompatible. Most of the past “merging” efforts have mostly
concentrated on attempts to “quantize” general relativity but they have been so
far either unsuccessful or have ended up to unfalsifiable theories. This has
stimulated a critical rethinking of the basis of today physics pillar theories,
especially of QM. I will present some of this alternative ideas, their pro and
con following the analysis path championed by R. Penrose and L. Smoolin whose
ultimate aim is to build a new physical theory based on the idea that a real
world exists (independently from one of us watching it) and Physics is the
science to understand how it really works.

Titolo X-exoplanets and the quest for the He I 10830 triplet in exoplanets

Abstract

Exoplanet atmospheres photoevaporate because of XUV stellar irradiation.
Evaporation signs are mainly detected through the h Lyman-alpha line, or
more recently in the He I 10830 triplet. Despite of early efforts back
in 2000, it was not until 2018 that the line was detected in exoplanet
atmospheres. The He I line is not affected by interstellar medium
absorption, and that is pushing a number of observations to search for
its presence in exoplanet atmospheres. The stellar high energy
irradiation also plays a role in this line formation. But all the
attempts to relate the stellar XUV irradiation and the presence of the
line in exoplanets have ended in just a suggestive trend. Studies
related to photoevaporation, and also on the He I 10830 line, show the
importance of having good models of the XUV stellar emission. Along this
talk I will describe the update done to our early X-exoplanet models,
and how this accurate work has allowed us to define a clear correlation
between XUV stellar irradiation and the detection of He I 10830 triplet
in exoplanet atmospheres. Some hints on the future development of XUV
modelling will be discussed.

ref. Laura