BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:There is only one time DTSTART;VALUE=DATE-TIME:20211011T125500Z DTEND;VALUE=DATE-TIME:20211011T132000Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-375@cern.ch DESCRIPTION:Speakers: Alessandro Cuccoli (Università di Firenze - Diparti mento di Fisica)\nWe draw a picture of physical systems allowing us to rec ognize what is the thing we call ”time”. Elements of the picture are t wo non-interacting\, entangled quantum systems: one acting as a clock\, an d the other one as the evolving system. The setting is based on the ”Pag e and Wootters mechanism”\, with tools from Lie-Group and large-N quantu m approaches. The theoretical framework\, based on a parametric representa tion with generalized coherent states\, allows us to take the classical li mit either of the clock only\, or of the clock and the evolving system\; w e derive the Schrödinger equation in the first case\, and Hamilton's equa tions in the second one\, showing that there is only one time\, that is a manifestation of entanglement.\n\nhttps://indico.unina.it/event/52/contrib utions/375/ LOCATION: URL:https://indico.unina.it/event/52/contributions/375/ END:VEVENT BEGIN:VEVENT SUMMARY:Entanglement between remote ions interfaced with cavities DTSTART;VALUE=DATE-TIME:20211011T143500Z DTEND;VALUE=DATE-TIME:20211011T150000Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-382@cern.ch DESCRIPTION:Speakers: Maria Galli (University of Innsbruck)\nIn a quantum network\, entanglement between qubits located in remote nodes is a fundame ntal resource for different applications including distributed quantum com puting and quantum repeaters. Once can generate entanglement between dista nt ions by creating an ion-photon entangled pair at each of the two networ k nodes\, steering the photons to opposite ports of a beamsplitter\, and s ubsequently detect them. Specific photon detection patterns herald the gen eration of the ion-ion entangled state.\nTwo remote ions have previously b een entangled over a separation of a few meters. Here\, we present entang lement generation between ions stored in remote nodes in separate building s in Innsbruck\, connected via a fiber link of 400 m\, where the trapped i ons are interfaced with optical cavities.\n\nhttps://indico.unina.it/event /52/contributions/382/ LOCATION: URL:https://indico.unina.it/event/52/contributions/382/ END:VEVENT BEGIN:VEVENT SUMMARY:Thouless pumping of photons DTSTART;VALUE=DATE-TIME:20211011T141000Z DTEND;VALUE=DATE-TIME:20211011T143500Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-381@cern.ch DESCRIPTION:Speakers: Valentina Brosco (Istituto dei Sistemi Complessi\, C NR and Physics Department\, Università di Roma "La Sapienza")\nNon-abelia n gauge fields emerge naturally in the description of adiabatically evolvi ng quantum systems. In this talk we show that they also play a role in Tho uless pumping in the presence of degenerate bands. Specifically\, we consi der a photonic Lieb lattice and show that when the lattice parameters are slowly modulated\, the propagation of the photons bear the fingerprints of the underlying non-abelian gauge structure. \nThe non-dispersive characte r of the bands enables a high degree of control on photon propagation. Our work paves the way to the generation and detection of non-abelian gauge f ields in photonic and optical lattices. The talk includes a review of abe lian pumping in photonic and superconducting systems and perspectives on q uantum applications of photonic pumps.\n\nhttps://indico.unina.it/event/52 /contributions/381/ LOCATION: URL:https://indico.unina.it/event/52/contributions/381/ END:VEVENT BEGIN:VEVENT SUMMARY:On the notion of causal influence DTSTART;VALUE=DATE-TIME:20211011T134500Z DTEND;VALUE=DATE-TIME:20211011T141000Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-380@cern.ch DESCRIPTION:Speakers: Paolo Perinotti (Università di Pavia)\nWe address t he question whether a reversible transformation produces a causal influenc e from one of its input systems to one of its outputs. In quantum theory c ausal influence is typically identified with signalling. A second notion i s borrowed from the theory of quantum cellular automata. We adopt an exten sion of the latter\, in the context of general probabilistic theories. We show that in the quantum case the two notions coincide\, while in classica l theory they are different. Following the proof of equivalence in the qua ntum case\, we identify a general condition under which the two definition s coincide\, i.e. "no interaction without disturbance". We show an algebra ic construction that is useful for the analysis of causal influence in rev ersible processes.\n\nhttps://indico.unina.it/event/52/contributions/380/ LOCATION: URL:https://indico.unina.it/event/52/contributions/380/ END:VEVENT BEGIN:VEVENT SUMMARY:Quantum gravitational decoherence DTSTART;VALUE=DATE-TIME:20211011T132000Z DTEND;VALUE=DATE-TIME:20211011T134500Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-379@cern.ch DESCRIPTION:Speakers: Luciano Petruzziello (University of Salerno & INFN - National Institute for Nuclear Physics)\nWe discuss a decoherence process due to quantum gravity effects. We assume a foamy quantum spacetime with a fluctuating minimal length coinciding on average with the Planck scale. Considering deformed canonical commutation relations with a fluctuating de formation parameter\, we derive a Lindblad master equation that yields loc alization in energy space and decoherence times consistent with the availa ble observational evidence. Finally\, we comment on possible experimental tests based on cavity optomechanics setups with ultracold massive molecula r oscillators and provide preliminary estimates on the values of the physi cal parameters needed for actual laboratory implementations\n\nhttps://ind ico.unina.it/event/52/contributions/379/ LOCATION: URL:https://indico.unina.it/event/52/contributions/379/ END:VEVENT BEGIN:VEVENT SUMMARY:The four postulates of quantum mechanics are three DTSTART;VALUE=DATE-TIME:20211011T123000Z DTEND;VALUE=DATE-TIME:20211011T125500Z DTSTAMP;VALUE=DATE-TIME:20261018T005749Z UID:indico-contribution-83-377@cern.ch DESCRIPTION:Speakers: Lorenzo Maccone (Universita' di Pavia)\nThe tensor p roduct postulate of quantum mechanics states that the Hilbert space of a c omposite system is the tensor product of the components' Hilbert spaces. A ll current formalizations of quantum mechanics that do not contain this po stulate contain some equivalent postulate or assumption (sometimes hidden) . Here we give a natural definition of composite system as a set containin g the component systems and show how one can logically derive the tensor p roduct rule from the state postulate and from the measurement postulate. I n other words\, our paper reduces by one the number of postulates necessar y to quantum mechanics.\n\nThis talk is based on the paper: \nG.Carcassi\, L.Maccone\,C.A.Aidala\, The four postulates of quantum mechanics are three \, Phys. Rev. Lett. 126\, 110402 (2021).\n\nhttps://indico.unina.it/event/ 52/contributions/377/ LOCATION: URL:https://indico.unina.it/event/52/contributions/377/ END:VEVENT END:VCALENDAR