With the upcoming HL-LHC, the budget for computing will be insufficient to generate a sufficient amount of Monte-Carlo events for both signal and background predictions. The driving force behind these costs is the inefficiency of the Monte-Carlo phase space generators and the unweighting efficiencies.

After a short review of traditional algorithms, I will introduce a new Machine Learning algorithm that uses Normalizing Flows for efficient numerical integration and random sampling. This approach is especially efficient in high-dimensional integration spaces. I will show some preliminary results obtained with the matrix element generator of Sherpa and discuss different choices of hyperparameters and their influence on the result.

We analyse a gedankenexperiment previously considered by Mari et al. that involves quantum superpositions of charged and/or massive bodies ("particles'') under the control of the observers, Alice and Bob. In the electromagnetic case, we show that the quantization of electromagnetic radiation (which causes decoherence of Alice's particle) and vacuum fluctuations of the electromagnetic field (which limits Bob's ability to localize his particle to better than a charge-radius) both are essential for avoiding apparent paradoxes with causality and complementarity. We then analyze the gravitational version of this gedankenexperiment. We show that the analysis of the gravitational case is in complete parallel with the electromagnetic case provided that gravitational radiation is quantized and that vacuum fluctuations limit the localization of a particle to no better than a Planck length. This provides support for the view that (linearized) gravity should have a quantum field description.

]]>Axion and Axion-like particles are fascinating dark matter candidates and a great effort has been devoted to their study, both theoretically and experimentally. In this talk I will discuss two different astrophysical searches. One consists in looking with radio telescopes for the spontaneous decay of axion dark matter using different targets as Dwarf Galaxies, Clusters or the Galactic Center. The second one uses the parity violating axion interactions to exploit the extreme precision of pulsar timing measurements and look for oscillations in the polarization angle of the pulsar signal.

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