Phenomenology and theory of galactic cosmic-ray propagation

Understanding the cosmic-ray (CR) transport in the Milky Way magnetic field is fundamental to unveil their galactic factories. While we know now that they can be created in supernovas, there may be other sources available for CR acceleration. To trace back CR origins we can look at what they are made of. By weighing the different isotopes of elements that hit CR detectors, we can infer global properties as the galactic grammage and escape time.

Simulating gravitational wave production during a vacuum phase transition

In this talk I will discuss cosmological first-order phase transitions. These phase transitions which proceed through the nucleation and merger of bubbles on the new phase are known to source gravitational waves. If one of these events occurred in the early universe then upcoming space based gravitational wave detectors like LISA may be able to detect the resulting gravitational wave background that remains today. In this talk I will focus on transitions in which the bubble wall accelerates until collision.

Evolution of magnetic fields in the early Universe

Magnetic fields are observed on virtually all astrophysical scales of the modern Universe, from planets and stars to galaxies and galaxy clusters. Observations of blazars suggest that even the intergalactic medium is permeated by magnetic fields. Such large-scale fields were most likely generated very shortly after the Big Bang and therefore are a unique window into the physics of the very early Universe.

Quantum gravity Induced Entanglement of Masses (QGEM) protocol

Understanding gravity in the framework of quantum mechanics is one of the great challenges in modern physics. Along this line, a prime question is to find whether gravity is a quantum entity subject to the rules of quantum mechanics. It is fair to say that there are no feasible ideas yet to test the quantum coherent behaviour of gravity directly in a laboratory experiment. Here, I will introduce an idea for such a test based on the principle that two objects cannot be entangled without a quantum mediator.

Euclidean Wormholes and Holography

Wormholes are exotic solutions of General Relativity that still challenge our physical intuition. In this talk I will first review and distinguish various types of wormholes along with their expected physical properties. I will then focus on asymptotically AdS wormhole solutions in the context of holography. I will explain how to compute correlation functions of local operators as well as non local observables such as correlation functions of Wilson loops on the distinct boundaries and discuss their behavior.


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