Publications

@article{Bassi2026,

title = {Quantum foundations for quantum technologies in the International Year of Quantum (2025)},

author = {A Bassi},

doi = {10.1088/2058-9565/ae49bc},

issn = {2058-9565},

year  = {2026},

date = {2026-06-01},

journal = {Quantum Sci. Technol.},

volume = {11},

number = {2},

publisher = {IOP Publishing},

abstract = {Abstract

                  From the very beginning, quantum mechanics has been accompanied by crucial foundational questions: the possibility of visualizing physical processes, the limits of measurement epitomized by Heisenberg’s uncertainty principle, the existence of a deeper underlying reality with additional degrees of freedom, the role of measurements, and the status of locality. Long regarded as philosophical speculations, these issues were progressively reformulated into precise mathematical statements and ultimately subjected to experimental verification. The trajectory proved unpredictable: questions once dismissed as metaphysical gave rise to experimental platforms, which in turn matured into devices and technologies powering quantum computation, communication, and sensing. Yet this development is not unidirectional: advances in technology also feed back into foundations, enabling tests of principles that were previously out of reach—for example, whether quantum superposition persists at larger and larger scales and whether reality, gravity included, is fundamentally quantum. In this way, the dialogue between foundational inquiry and technological progress continues to shape both our theoretical understanding and the practical realization of quantum phenomena.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2026,

title = {From equivalent Lagrangians to inequivalent open quantum system dynamics},

author = {Anirudh Gundhi and Oliviero Angeli and Angelo Bassi},

doi = {10.1103/4rpx-zj2x},

issn = {2643-1564},

year  = {2026},

date = {2026-02-06},

journal = {Phys. Rev. Research},

volume = {8},

number = {1},

publisher = {American Physical Society (APS)},

abstract = {<jats:p>Lagrangians can differ by a total derivative without altering the equations of motion, thus encoding the same physics. This is true both classically and quantum mechanically. We show, however, that in the context of open quantum systems, two Lagrangians that differ by a total derivative can lead to inequivalent reduced dynamics. While these Lagrangians are connected via unitary transformations at the level of the global system-plus-environment description, the equivalence breaks down after tracing out the environment. We argue that only those Lagrangians for which the canonical and mechanical momenta of the system coincide lead to operationally meaningful dynamics. Applying this insight to quantum electrodynamics (QED), we derive the master equation for bremsstrahlung due to an accelerated nonrelativistic electron upto second order in the interaction. The resulting reduced dynamics predicts decoherence in the position basis and closely matches the Caldeira-Leggett form, thus resolving previous discrepancies in the literature. Our findings have implications for both QED and gravitational decoherence, where similar ambiguities arise.</jats:p>},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gaona-Reyes2025,

title = {Theoretical limits of protocols for distinguishing different unravelings},

author = {J. L. Gaona-Reyes and D. G. A. Altamura and A. Bassi},

doi = {10.1103/6qnt-t3wl},

issn = {2643-1564},

year  = {2025},

date = {2025-12-15},

journal = {Phys. Rev. Research},

volume = {7},

number = {4},

publisher = {American Physical Society (APS)},

abstract = {<jats:p>Stochastic unravelings of Lindblad-type master equations, such as stochastic Schrödinger equations, provide powerful tools to model open quantum systems and continuous measurement processes. The same master equation can be unraveled in different ways; while these unravelings differ at the level of quantum trajectories, by construction they all yield the same averaged dynamics for the density operator. A recent question of both foundational and practical relevance is whether such unravelings can be operationally distinguished, given that certain nonlinear quantities—such as covariances and higher-order moments of conditional expectation values—are unraveling dependent. We show that these quantities cannot be accessed unless the measurement scheme (i.e., the unraveling) is known in advance. This renders any operational protocol to distinguish unravelings fundamentally unfeasible. We further establish that assuming access to such nonlinear quantities without prior knowledge of the unraveling would enable superluminal signaling, violating relativistic causality.</jats:p>},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piccione2025c,

title = {Hybrid classical-quantum Newtonian gravity with stable vacuum},

author = {Nicolò Piccione and Angelo Bassi},

doi = {10.1088/1361-6382/ae1540},

issn = {1361-6382},

year  = {2025},

date = {2025-11-21},

journal = {Class. Quantum Grav.},

volume = {42},

number = {22},

publisher = {IOP Publishing},

abstract = {Abstract

                  We investigate the gravitational Poissonian spontaneous localization (GPSL) model, a hybrid classical-quantum model in which classical Newtonian gravity emerges from stochastic collapses of the mass density operator, and consistently couples to quantum matter. Unlike models based on continuous weak measurement schemes, we show that GPSL ensures vacuum stability; this, together with its applicability to identical particles and fields, makes it a promising candidate for a relativistic generalization. We analyze the model’s general properties, and compare its predictions with those based on continuous weak measurement schemes. Notably, here the gravitational feedback enters entirely through the non-Hermitian jump operators, without modifying the unitary part of the dynamics. We show that this leads to a short-range gravitational back-reaction and permits decoherence rates below those of any model based on continuous weak measurement schemes. We provide explicit examples, including the dynamics of a single particle and a rigid sphere, to illustrate the distinctive phenomenology of the model. Finally, we discuss the experimental testability of GPSL, highlighting both interferometric and non-interferometric strategies to constrain its parameters and distinguish it from competing models.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2025,

title = {Measuring Decoherence Due to Quantum Vacuum Fluctuations},

author = {Anirudh Gundhi and Hendrik Ulbricht},

doi = {10.1103/s5c9-zjt9},

issn = {1079-7114},

year  = {2025},

date = {2025-07-00},

journal = {Phys. Rev. Lett.},

volume = {135},

number = {2},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piccione2025,

title = {Exploring the effects of mass dependence in spontaneous collapse models},

author = {Nicolò Piccione and Angelo Bassi},

doi = {10.1103/2yy5-tj85},

issn = {2469-9934},

year  = {2025},

date = {2025-07-00},

journal = {Phys. Rev. A},

volume = {112},

number = {1},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Angeli2025,

title = {Entanglement in Markovian hybrid classical-quantum theories of gravity},

author = {Oliviero Angeli and Matteo Carlesso},

doi = {10.1103/jzht-fbwt},

issn = {2470-0029},

year  = {2025},

date = {2025-07-00},

journal = {Phys. Rev. D},

volume = {112},

number = {2},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Paparelle2025,

title = {Experimental direct quantum communication with squeezed states},

author = {Iris Paparelle and Faezeh Mousavi and Francesco Scazza and Angelo Bassi and Matteo Paris and Alessandro Zavatta},

doi = {10.1364/oe.538593},

issn = {1094-4087},

year  = {2025},

date = {2025-06-30},

journal = {Opt. Express},

volume = {33},

number = {14},

publisher = {Optica Publishing Group},

abstract = {<jats:p>Quantum secure direct communication (QSDC) is an evolving quantum communication framework based on transmitting secure information directly through a quantum channel, without relying on key-based encryption such as in quantum key distribution (QKD). Optical QSDC protocols, utilizing discrete and continuous variable encodings, show great promise for future technological applications. We present the first table-top continuous-variable QSDC proof of principle, analyzing its implementation and comparing the use of coherent against squeezed light sources. A simple beam-splitter attack is analyzed by using Wyner wiretap channel theory. Our study illustrates the advantage of squeezed states over coherent ones for enhanced security and reliable communication in lossy and noisy channels. Our practical implementation, utilizing mature telecom components, could foster secure quantum metropolitan networks compatible with advanced multiplexing systems.</jats:p>},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Abdalla2025,

title = {Terrestrial Very-Long-Baseline Atom Interferometry: summary of the second workshop},

author = {Adam Abdalla and Angelo Bassi and Matteo Carlesso and et al},

url = {https://link.springer.com/article/10.1140/epjqt/s40507-025-00344-3},

doi = {10.1140/epjqt/s40507-025-00344-3},

year  = {2025},

date = {2025-04-03},

urldate = {2025-04-03},

journal = {EPJ Quantum Technology},

volume = {12},

number = {42},

abstract = {This summary of the second Terrestrial Very-Long-Baseline Atom Interferometry (TVLBAI) Workshop provides a comprehensive overview of our meeting held in London in April 2024 (Second Terrestrial Very-Long-Baseline Atom Interferometry Workshop, Imperial College, April 2024), building on the initial discussions during the inaugural workshop held at CERN in March 2023 (First Terrestrial Very-Long-Baseline Atom Interferometry Workshop, CERN, March 2023). Like the summary of the first workshop (Abend et al. in AVS Quantum Sci. 6:024701, 2024), this document records a critical milestone for the international atom interferometry community. It documents our concerted efforts to evaluate progress, address emerging challenges, and refine strategic directions for future large-scale atom interferometry projects. Our commitment to collaboration is manifested by the integration of diverse expertise and the coordination of international resources, all aimed at advancing the frontiers of atom interferometry physics and technology, as set out in a Memorandum of Understanding signed by over 50 institutions (Memorandum of Understanding for the Terrestrial Very Long Baseline Atom Interferometer Study).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Altamura2025,

title = {Improved bounds on collapse models from rotational noise of the Laser Interferometer Space Antenna Pathfinder mission},

author = {Davide Giordano Ario Altamura and Andrea Vinante and Matteo Carlesso},

doi = {10.1103/physreva.111.l020203},

issn = {2469-9934},

year  = {2025},

date = {2025-02-00},

journal = {Phys. Rev. A},

volume = {111},

number = {2},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Muffato2025,

title = {Generation of classical non-Gaussian states by squeezing a thermal state into nonlinear motion of levitated optomechanics},

author = {R. Muffato and T. S. Georgescu and J. Homans and T. Guerreiro and Q. Wu and D. A. Chisholm and M. Carlesso and M. Paternostro and H. Ulbricht},

doi = {10.1103/physrevresearch.7.013171},

issn = {2643-1564},

year  = {2025},

date = {2025-02-00},

journal = {Phys. Rev. Research},

volume = {7},

number = {1},

publisher = {American Physical Society (APS)},

abstract = {We report on an experiment achieving the dynamical generation of non-Gaussian states of motion of a levitated optomechanical system. We access intrinsic Duffing-like nonlinearities by thermal squeezing of an oscillator's state of motion by rapidly switching the frequency of its trap. We characterize the experimental non-Gaussian state versus expectations from simulations and give prospects for the emergence of genuine nonclassical features.

          

            

            

              

                Published by the American Physical Society

                2025

              

            

          },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Crognaletti2024,

title = {Equivariant Variational Quantum Eigensolver to detect phase transitions through energy level crossings},

author = {Giulio Crognaletti and Giovanni Di Bartolomeo and Michele Vischi and Luciano Loris Viteritti},

doi = {10.1088/2058-9565/ad9be3},

issn = {2058-9565},

year  = {2025},

date = {2025-01-01},

journal = {Quantum Sci. Technol.},

volume = {10},

number = {1},

publisher = {IOP Publishing},

abstract = {Abstract

               Level spectroscopy stands as a powerful method for identifying the transition point that delineates distinct quantum phases. Since each quantum phase exhibits a characteristic sequence of excited states, the crossing of energy levels between low-lying excited states offers a reliable mean to estimate the phase transition point. While approaches like the Variational Quantum Eigensolver are useful for approximating ground states of interacting systems using quantum computing, capturing low-energy excitations remains challenging. In our study, we introduce an equivariant quantum circuit that preserves the total spin and the translational symmetry to accurately describe singlet and triplet excited states in the J

                  1–J

                  2 Heisenberg model on a chain, which are crucial for characterizing its transition point. Additionally, we assess the impact of noise on the variational state, showing that conventional mitigation techniques like Zero Noise Extrapolation reliably restore its physical properties.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2024,

title = {Decoherence due to the Casimir effect?},

author = {Anirudh Gundhi},

doi = {10.1103/physrevd.110.116001},

issn = {2470-0029},

year  = {2024},

date = {2024-12-00},

journal = {Phys. Rev. D},

volume = {110},

number = {11},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DiBartolomeo2024b,

title = {Efficient quantum algorithm to simulate open systems through a single environmental qubit},

author = {Giovanni Di Bartolomeo and Michele Vischi and Tommaso Feri and Angelo Bassi and Sandro Donadi},

doi = {10.1103/physrevresearch.6.043321},

issn = {2643-1564},

year  = {2024},

date = {2024-12-00},

journal = {Phys. Rev. Research},

volume = {6},

number = {4},

publisher = {American Physical Society (APS)},

abstract = {We present an efficient algorithm for simulating open quantum systems dynamics described by the Lindblad master equation on quantum computers, addressing key challenges in the field. In contrast to existing approaches, our method achieves two significant advancements. First, we employ a repetition of unitary gates on a set of n system qubits and, remarkably, only a single ancillary bath qubit representing the environment. It follows that, for the typical case of m locality of the Lindblad operators, we reach an exponential improvement of the number of ancilla in terms of m and up to a polynomial improvement in ancilla overhead for large n with respect to other approaches. Although stochasticity is introduced, requiring multiple circuit realizations, the sampling overhead is independent of the system size. Second, we show that, under fixed accuracy conditions, our algorithm enables a reduction in the number of Trotter steps compared to other approaches, substantially decreasing circuit depth. These advancements hold particular significance for near-term quantum computers, where minimizing both width and depth is critical due to inherent noise in their dynamics.

          

            

            

              

                Published by the American Physical Society

                2024

              

            

          },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piccione2024b,

title = {Exploring the Accuracy of Interferometric Quantum Measurements under Conservation Laws},

author = {Nicolò Piccione and Maria Maffei and Andrew N. Jordan and Kater W. Murch and Alexia Auffèves},

doi = {10.1103/physrevlett.133.240202},

issn = {1079-7114},

year  = {2024},

date = {2024-12-00},

journal = {Phys. Rev. Lett.},

volume = {133},

number = {24},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Lenler-Eriksen2024,

title = {Testing continuous spontaneous localization model with charged macromolecules},

author = {Emil Lenler-Eriksen and Michael Drewsen and Matteo Carlesso},

doi = {10.1088/1367-2630/ad904a},

issn = {1367-2630},

year  = {2024},

date = {2024-11-01},

journal = {New J. Phys.},

volume = {26},

number = {11},

publisher = {IOP Publishing},

abstract = {Abstract

               In the last decade, a growing interest has been devoted to models of spontaneous collapse of the wavefunction, known also as collapse models. They coherently solve the well-known quantum measurement problem by suitably modifying the Schrödinger evolution. Quantum experiments are now finally within the reach of testing such models (and thus testing the limits of quantum theory). Here, we propose a method based on a two-ions confined in a linear Paul trap to possibly enhance the testing capabilities of such experiments. The combination of an atomic and a macromolecular ion provide a good match for the cooling of the motional degrees of freedom and a non-negligible insight in the collapse mechanism, respectively.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Figurato2024b,

title = {On the effectiveness of the collapse in the Diósi–Penrose model},

author = {Laria Figurato and Marco Dirindin and José Luis Gaona-Reyes and Matteo Carlesso and Angelo Bassi and Sandro Donadi},

doi = {10.1088/1367-2630/ad8c77},

issn = {1367-2630},

year  = {2024},

date = {2024-11-01},

journal = {New J. Phys.},

volume = {26},

number = {11},

publisher = {IOP Publishing},

abstract = {Abstract

               The possibility that gravity plays a role in the collapse of the quantum wave function has been considered in the literature, and it is of relevance not only because it would provide a solution to the measurement problem in quantum theory, but also because it would give a new and unexpected twist to the search for a unified theory of quantum and gravitational phenomena, possibly overcoming the current impasse. The Diósi–Penrose model is the most popular incarnation of this idea. It predicts a progressive breakdown of quantum superpositions when the mass of the system increases; as such, it is susceptible to experimental verification. Current experiments set a lower bound 

                     

                     

                        

                           

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                   Å  for the free parameter of the model, excluding some versions of it. In this work we search for an upper bound, coming from the request that the collapse is effective enough to guarantee classicality at the macroscopic scale: we find out that not all macroscopic systems collapse effectively. If one relaxes this request, a reasonable (although to some degree arbitrary) bound is found to be: 

                     

                     

                        

                           

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                   Å. This will serve to better direct future experiments to further test the model.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vischi2024,

title = {Simulating photonic devices with noisy optical elements},

author = {Michele Vischi and Giovanni Di Bartolomeo and Massimiliano Proietti and Seid Koudia and Filippo Cerocchi and Massimiliano Dispenza and Angelo Bassi},

doi = {10.1103/physrevresearch.6.033337},

issn = {2643-1564},

year  = {2024},

date = {2024-09-00},

journal = {Phys. Rev. Research},

volume = {6},

number = {3},

publisher = {American Physical Society (APS)},

abstract = {Quantum computers are inherently affected by noise. While in the long term, error correction codes will account for noise at the cost of increasing physical qubits, in the near term, the performance of any quantum algorithm should be tested and simulated in the presence of noise. As noise acts on the hardware, the classical simulation of a quantum algorithm should not be agnostic on the platform used for the computation. In this paper, we apply the recently proposed noisy gates approach to efficiently simulate noisy optical circuits described in the dual rail framework. The evolution of the state vector is simulated directly, without requiring the mapping to the density matrix framework. Notably, we test the method on both the gate-based and measurement-based quantum computing models, showing that the approach is very versatile. We also evaluate the performance of a photonic variational quantum algorithm to solve the MAX-2-CUT problem. In particular we design and simulate an ansatz, which is resilient to photon losses up to p∼10−3 making it relevant for near-term applications.

          

            

            

              

                Published by the American Physical Society

                2024

              

            

          },

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wu2024,

title = {Squeezing below the ground state of motion of a continuously monitored levitating nanoparticle},

author = {Qiongyuan Wu and Diana A Chisholm and Rafael Muffato and Tiberius Georgescu and Jack Homans and Hendrik Ulbricht and Matteo Carlesso and Mauro Paternostro},

doi = {10.1088/2058-9565/ad7284},

issn = {2058-9565},

year  = {2024},

date = {2024-08-22},

journal = {Quantum Sci. Technol.},

publisher = {IOP Publishing},

abstract = {Abstract

               Squeezing is a crucial resource for quantum information processing and quantum sensing. In levitated nanomechanics, squeezed states of motion can be generated via temporal control of the trapping frequency of a massive particle. However, the amount of achievable squeezing typically suffers from detrimental environmental effects. We analyze the performance of a scheme that, by embedding careful time-control of trapping potentials and fully accounting for the most relevant sources of noise – including measurement backaction – achieves significant levels of mechanical squeezing. The feasibility of our proposal, which is close to experimental state-of-the-art, makes it a valuable tool for quantum state engineering.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Altamura2024,

title = {Noninterferometric rotational test of the continuous spontaneous localization model: Enhancement of the collapse noise through shape optimization},

author = {Davide Giordano Ario Altamura and Matteo Carlesso and Sandro Donadi and Angelo Bassi},

doi = {10.1103/physreva.109.062212},

issn = {2469-9934},

year  = {2024},

date = {2024-06-00},

journal = {Phys. Rev. A},

volume = {109},

number = {6},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piscicchia2024,

title = {X-Ray Emission from Atomic Systems Can Distinguish between Prevailing Dynamical Wave-Function Collapse Models},

author = {Kristian Piscicchia and Sandro Donadi and Simone Manti and Angelo Bassi and Maaneli Derakhshani and Lajos Diósi and Catalina Curceanu},

doi = {10.1103/physrevlett.132.250203},

issn = {1079-7114},

year  = {2024},

date = {2024-06-00},

journal = {Phys. Rev. Lett.},

volume = {132},

number = {25},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{nokey,

title = {Terrestrial very-long-baseline atom interferometry: Workshop summary},

author = {Sven Abend; Baptiste Allard; Iván Alonso; John Antoniadis; Henrique Araújo; Gianluigi Arduini; Aidan S. Arnold; Tobias Asano; Nadja Augst; Leonardo Badurina; Antun Balaž; Hannah Banks; Michele Barone; Michele Barsanti; Angelo Bassi; Baptiste Battelier; Charles F. A. Baynham; Quentin Beaufils; Aleksandar Belić; Ankit Beniwal; Jose Bernabeu; Francesco Bertinelli; Andrea Bertoldi; Ikbal Ahamed Biswas; Diego Blas; Patrick Boegel; Aleksandar Bogojević; Jonas Böhm; Samuel Böhringer; Kai Bongs; Philippe Bouyer; Christian Brand; Apostolos Brimis; Oliver Buchmueller; Luigi Cacciapuoti; Sergio Calatroni; Benjamin Canuel; Chiara Caprini; Ana Caramete; Laurentiu Caramete; Matteo Carlesso; et al},

url = {https://pubs.aip.org/avs/aqs/article/6/2/024701/3290457},

doi = {10.1116/5.0185291},

year  = {2024},

date = {2024-05-07},

urldate = {2024-05-07},

journal = {AVS Quantum Science},

volume = {6},

issue = {2},

pages = {024701},

abstract = {This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight dark matter and gravitational waves. The primary objective of the workshop was to lay the groundwork for an international TVLBAI proto-collaboration. This collaboration aims to unite researchers from different institutions to strategize and secure funding for terrestrial large-scale AI projects. The ultimate goal is to create a roadmap detailing the design and technology choices for one or more kilometer--scale detectors, which will be operational in the mid-2030s. The key sections of this report present the physics case and technical challenges, together with a comprehensive overview of the discussions at the workshop together with the main conclusions.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piccione2024,

title = {Reservoir-Free Decoherence in Flying Qubits},

author = {Nicolò Piccione and Léa Bresque and Andrew N. Jordan and Robert S. Whitney and Alexia Auffèves},

doi = {10.1103/physrevlett.132.220403},

issn = {1079-7114},

year  = {2024},

date = {2024-05-00},

urldate = {2024-05-00},

journal = {Phys. Rev. Lett.},

volume = {132},

number = {22},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DiBartolomeo2024,

title = {Experimental bounds on linear-friction dissipative collapse models from levitated optomechanics},

author = {Giovanni Di Bartolomeo and Matteo Carlesso},

doi = {10.1088/1367-2630/ad3842},

issn = {1367-2630},

year  = {2024},

date = {2024-04-01},

journal = {New J. Phys.},

volume = {26},

number = {4},

publisher = {IOP Publishing},

abstract = {Abstract

               Collapse models constitute an alternative to quantum mechanics that solve the well-know quantum measurement problem. In this framework, a novel approach to include dissipation in collapse models has been recently proposed, and awaits experimental scrutiny. Our work establishes experimental bounds on the so-constructed linear-friction dissipative Diósi-Penrose (dDP) and Continuous Spontaneous localisation (dCSL) models by exploiting experiments in the field of levitated optomechanics. Our results in the dDP case exclude collapse temperatures below 10−13 K and 

                     

                     

                        

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                   K respectively for values of the localisation length smaller than 10−6 m and 10−8 m. In the dCSL case the entire parameter space is excluded for values of the temperature lower than 

                     

                     

                        

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                   K.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gaona-Reyes2024,

title = {Spontaneous collapse models lead to the emergence of classicality of the Universe},

author = {José Luis Gaona-Reyes and Lucía Menéndez-Pidal and Mir Faizal and Matteo Carlesso},

doi = {10.1007/jhep02(2024)193},

issn = {1029-8479},

year  = {2024},

date = {2024-02-00},

journal = {J. High Energ. Phys.},

volume = {2024},

number = {2},

publisher = {Springer Science and Business Media LLC},

abstract = {Abstract

                     Assuming that Quantum Mechanics is universal and that it can be applied over all scales, then the Universe is allowed to be in a quantum superposition of states, where each of them can correspond to a different space-time geometry. How can one then describe the emergence of the classical, well-defined geometry that we observe? Considering that the decoherence-driven quantum-to-classical transition relies on external physical entities, this process cannot account for the emergence of the classical behaviour of the Universe. Here, we show how models of spontaneous collapse of the wavefunction can offer a viable mechanism for explaining such an emergence. We apply it to a simple General Relativity dynamical model for gravity and a perfect fluid. We show that, by starting from a general quantum superposition of different geometries, the collapse dynamics leads to a single geometry, thus providing a possible mechanism for the quantum-to-classical transition of the Universe. Similarly, when applying our dynamics to the physically-equivalent Parametrised Unimodular gravity model, we obtain a collapse on the basis of the cosmological constant, where eventually one precise value is selected, thus providing also a viable explanation for the cosmological constant problem. Our formalism can be easily applied to other quantum cosmological models where we can choose a well-defined clock variable.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Figurato2024,

title = {On the testability of the Károlyházy model},

author = {Laria Figurato and Angelo Bassi and Sandro Donadi},

doi = {10.1088/1367-2630/ad1499},

issn = {1367-2630},

year  = {2024},

date = {2024-01-01},

journal = {New J. Phys.},

volume = {26},

number = {1},

publisher = {IOP Publishing},

abstract = {Abstract

               Károlyházy’s original proposal, suggesting that space-time fluctuations could be a source of decoherence in space, faced a significant challenge due to an unexpectedly high emission of radiation (13 orders of magnitude more than what was observed in the latest experiment). To address this issue, we reevaluated Károlyházy’s assumption that the stochastic metric fluctuation must adhere to a wave equation. By considering more general correlation functions of space-time fluctuations, we resolve the problem and consequently revive the aforementioned proposal.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DiBartolomeo2023b,

title = {Noisy gates for simulating quantum computers},

author = {Giovanni Di Bartolomeo and Michele Vischi and Francesco Cesa and Roman Wixinger and Michele Grossi and Sandro Donadi and Angelo Bassi},

doi = {10.1103/physrevresearch.5.043210},

issn = {2643-1564},

year  = {2023},

date = {2023-12-00},

journal = {Phys. Rev. Research},

volume = {5},

number = {4},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Cesa2023,

title = {Universal Quantum Computation in Globally Driven Rydberg Atom Arrays},

author = {Francesco Cesa and Hannes Pichler},

doi = {10.1103/physrevlett.131.170601},

issn = {1079-7114},

year  = {2023},

date = {2023-10-00},

journal = {Phys. Rev. Lett.},

volume = {131},

number = {17},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{DiBartolomeo2023,

title = {Linear-friction many-body equation for dissipative spontaneous wave-function collapse},

author = {Giovanni Di Bartolomeo and Matteo Carlesso and Kristian Piscicchia and Catalina Curceanu and Maaneli Derakhshani and Lajos Diósi},

doi = {10.1103/physreva.108.012202},

issn = {2469-9934},

year  = {2023},

date = {2023-07-00},

journal = {Phys. Rev. A},

volume = {108},

number = {1},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Donadi2023,

title = {Collapse Dynamics Are Diffusive},

author = {Sandro Donadi and Luca Ferialdi and Angelo Bassi},

doi = {10.1103/physrevlett.130.230202},

issn = {1079-7114},

year  = {2023},

date = {2023-06-00},

journal = {Phys. Rev. Lett.},

volume = {130},

number = {23},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2023,

title = {Motion of an electron through vacuum fluctuations},

author = {Anirudh Gundhi and Angelo Bassi},

doi = {10.1103/physreva.107.062801},

issn = {2469-9934},

year  = {2023},

date = {2023-06-00},

journal = {Phys. Rev. A},

volume = {107},

number = {6},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Wu2023,

title = {Quantifying protocol efficiency: A thermodynamic figure of merit for classical and quantum state-transfer protocols},

author = {Qiongyuan Wu and Mario A. Ciampini and Mauro Paternostro and Matteo Carlesso},

doi = {10.1103/physrevresearch.5.023117},

issn = {2643-1564},

year  = {2023},

date = {2023-05-00},

journal = {Phys. Rev. Research},

volume = {5},

number = {2},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bassi2023,

title = {Collapse Models: A Theoretical, Experimental and Philosophical Review},

author = {Angelo Bassi and Mauro Dorato and Hendrik Ulbricht},

doi = {10.3390/e25040645},

issn = {1099-4300},

year  = {2023},

date = {2023-04-00},

journal = {Entropy},

volume = {25},

number = {4},

publisher = {MDPI AG},

abstract = {In this paper, we review and connect the three essential conditions needed by the collapse model to achieve a complete and exact formulation, namely the theoretical, the experimental, and the ontological ones. These features correspond to the three parts of the paper. In any empirical science, the first two features are obviously connected but, as is well known, among the different formulations and interpretations of non-relativistic quantum mechanics, only collapse models, as the paper well illustrates with a richness of details, have experimental consequences. Finally, we show that a clarification of the ontological intimations of collapse models is needed for at least three reasons: (1) to respond to the indispensable task of answering the question ’what are collapse models (and in general any physical theory) about?’; (2) to achieve a deeper understanding of their different formulations; (3) to enlarge the panorama of possible readings of a theory, which historically has often played a fundamental heuristic role.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Napolitano2023,

title = {Underground Tests of Quantum Mechanics by the VIP Collaboration at Gran Sasso},

author = {Fabrizio Napolitano and Andrea Addazi and Angelo Bassi and Massimiliano Bazzi and Mario Bragadireanu and Michael Cargnelli and Alberto Clozza and Luca De Paolis and Raffaele Del Grande and Maaneli Derakhshani and Sandro Donadi and Carlo Fiorini and Carlo Guaraldo and Mihail Iliescu and Matthias Laubenstein and Simone Manti and Antonino Marcianò and Johann Marton and Marco Miliucci and Edoardo Milotti and Kristian Piscicchia and Alessio Porcelli and Alessandro Scordo and Francesco Sgaramella and Diana Laura Sirghi and Florin Sirghi and Oton Vazquez Doce and Johann Zmeskal and Catalina Curceanu},

doi = {10.3390/sym15020480},

issn = {2073-8994},

year  = {2023},

date = {2023-02-00},

journal = {Symmetry},

volume = {15},

number = {2},

publisher = {MDPI AG},

abstract = {Modern physics lays its foundations on the pillars of Quantum Mechanics (QM), which has been proven successful to describe the microscopic world of atoms and particles, leading to the construction of the Standard Model. Despite the big success, the old open questions at its very heart, such as the measurement problem and the wave function collapse, are still open. Various theories consider scenarios which could encompass a departure from the predictions of the standard QM, such as extra-dimensions or deformations of the Lorentz/Poincaré symmetries. At the Italian National Gran Sasso underground Laboratory LNGS, we search for evidence of new physics proceeding from models beyond standard QM, using radiation detectors. Collapse models addressing the foundations of QM, such as the gravity-related Diósi–Penrose (DP) and Continuous Spontaneous Localization (CSL) models, predict the emission of spontaneous radiation, which allows experimental tests. Using a high-purity Germanium detector, we could exclude the natural parameterless version of the DP model and put strict bounds on the CSL one. In addition, forbidden atomic transitions could prove a possible violation of the Pauli Exclusion Principle (PEP) in open and closed systems. The VIP-2 experiment is currently in operation, aiming at detecting PEP-violating signals in Copper with electrons; the VIP-3 experiment upgrade is foreseen to become operative in the next few years. We discuss the VIP-Lead experiment on closed systems, and the strong bounds it sets on classes of non-commutative quantum gravity theories, such as the θ–Poincaré theory.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Ribezzo2022,

title = {Deploying an Inter‐European Quantum Network},

author = {Domenico Ribezzo and Mujtaba Zahidy and Ilaria Vagniluca and Nicola Biagi and Saverio Francesconi and Tommaso Occhipinti and Leif K. Oxenløwe and Martin Lončarić and Ivan Cvitić and Mario Stipčević and Žiga Pušavec and Rainer Kaltenbaek and Anton Ramšak and Francesco Cesa and Giorgio Giorgetti and Francesco Scazza and Angelo Bassi and Paolo De Natale and Francesco Saverio Cataliotti and Massimo Inguscio and Davide Bacco and Alessandro Zavatta},

doi = {10.1002/qute.202200061},

issn = {2511-9044},

year  = {2023},

date = {2023-02-00},

journal = {Adv Quantum Tech},

volume = {6},

number = {2},

publisher = {Wiley},

abstract = {AbstractAround 40 years have passed since the first pioneering works introduced the possibility of using quantum physics to enhance communications safety. Nowadays, quantum key distribution (QKD) exited the physics laboratories to become a mature technology, triggering the attention of States, military forces, banks, and private corporations. This work takes on the challenge of bringing QKD closer to a consumer technology: deployed optical fibers by telecommunication companies of different States have been used to realize a quantum network, the first‐ever connecting three different countries. This work also emphasizes the necessity of networks where QKD can come up besides classical communications, whose coexistence currently represents the main limitation of this technology. This network connects Trieste to Rijeka and Ljubljana via a trusted node in Postojna. A key rate of over 3 kbps in the shortest link and a 7‐hour‐long measurement demonstrate the system's stability and reliability. The network has been used to present the QKD at the G20 Digital Ministers' Meeting in Trieste. The experimental results, together with the interest that one of the most important events of international politics has attracted, showcase the maturity of the QKD technology bundle, placing it in the spotlight for consumer applications in the near term.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Piscicchia2023,

title = {A Novel Approach to Parameter Determination of the Continuous Spontaneous Localization Collapse Model},

author = {Kristian Piscicchia and Alessio Porcelli and Angelo Bassi and Massimiliano Bazzi and Mario Bragadireanu and Michael Cargnelli and Alberto Clozza and Luca De Paolis and Raffaele Del Grande and Maaneli Derakhshani and Diósi Lajos and Sandro Donadi and Carlo Guaraldo and Mihai Iliescu and Matthias Laubenstein and Simone Manti and Johann Marton and Marco Miliucci and Fabrizio Napolitano and Alessandro Scordo and Francesco Sgaramella and Diana Laura Sirghi and Florin Sirghi and Oton Vazquez Doce and Johann Zmeskal and Catalina Curceanu},

doi = {10.3390/e25020295},

issn = {1099-4300},

year  = {2023},

date = {2023-02-00},

journal = {Entropy},

volume = {25},

number = {2},

publisher = {MDPI AG},

abstract = {Models of dynamical wave function collapse consistently describe the breakdown of the quantum superposition with the growing mass of the system by introducing non-linear and stochastic modifications to the standard Schrödinger dynamics. Among them, Continuous Spontaneous Localization (CSL) was extensively investigated both theoretically and experimentally. Measurable consequences of the collapse phenomenon depend on different combinations of the phenomenological parameters of the model—the strength λ and the correlation length rC—and have led, so far, to the exclusion of regions of the admissible (λ−rC) parameters space. We developed a novel approach to disentangle the λ and rC probability density functions, which discloses a more profound statistical insight.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Kaltenbaek2023,

title = {Research campaign: Macroscopic quantum resonators (MAQRO)},

author = {Rainer Kaltenbaek and Markus Arndt and Markus Aspelmeyer and Peter F Barker and Angelo Bassi and James Bateman and Alessio Belenchia and Joel Bergé and Claus Braxmaier and Sougato Bose and Bruno Christophe and Garrett D Cole and Catalina Curceanu and Animesh Datta and Maxime Debiossac and Uroš Delić and Lajos Diósi and Andrew A Geraci and Stefan Gerlich and Christine Guerlin and Gerald Hechenblaikner and Antoine Heidmann and Sven Herrmann and Klaus Hornberger and Ulrich Johann and Nikolai Kiesel and Claus Lämmerzahl and Thomas W LeBrun and Gerard J Milburn and James Millen and Makan Mohageg and David C Moore and Gavin W Morley and Stefan Nimmrichter and Lukas Novotny and Daniel K L Oi and Mauro Paternostro and C Jess Riedel and Manuel Rodrigues and Loïc Rondin and Albert Roura and Wolfgang P Schleich and Thilo Schuldt and Benjamin A Stickler and Hendrik Ulbricht and Christian Vogt and Lisa Wörner},

doi = {10.1088/2058-9565/aca3cd},

issn = {2058-9565},

year  = {2023},

date = {2023-01-01},

journal = {Quantum Sci. Technol.},

volume = {8},

number = {1},

publisher = {IOP Publishing},

abstract = {Abstract

               The objective of the proposed macroscopic quantum resonators (MAQRO) mission is to harness space for achieving long free-fall times, extreme vacuum, nano-gravity, and cryogenic temperatures to test the foundations of physics in macroscopic quantum experiments at the interface with gravity. Developing the necessary technologies, achieving the required sensitivities and providing the necessary isolation of macroscopic quantum systems from their environment will lay the path for developing novel quantum sensors. Earlier studies showed that the proposal is feasible but that several critical challenges remain, and key technologies need to be developed. Recent scientific and technological developments since the original proposal of MAQRO promise the potential for achieving additional science objectives. The proposed research campaign aims to advance the state of the art and to perform the first macroscopic quantum experiments in space. Experiments on the ground, in micro-gravity, and in space will drive the proposed research campaign during the current decade to enable the implementation of MAQRO within the subsequent decade.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Bassi2022,

title = {A way forward for fundamental physics in space},

author = {A. Bassi and L. Cacciapuoti and S. Capozziello and S. Dell’Agnello and E. Diamanti and D. Giulini and L. Iess and P. Jetzer and S. K. Joshi and A. Landragin and C. Le Poncin-Lafitte and E. Rasel and A. Roura and C. Salomon and H. Ulbricht},

doi = {10.1038/s41526-022-00229-0},

issn = {2373-8065},

year  = {2022},

date = {2022-12-00},

journal = {npj Microgravity},

volume = {8},

number = {1},

publisher = {Springer Science and Business Media LLC},

abstract = {AbstractSpace-based research can provide a major leap forward in the study of key open questions in the fundamental physics domain. They include the validity of Einstein’s Equivalence principle, the origin and the nature of dark matter and dark energy, decoherence and collapse models in quantum mechanics, and the physics of quantum many-body systems. Cold-atom sensors and quantum technologies have drastically changed the approach to precision measurements. Atomic clocks and atom interferometers as well as classical and quantum links can be used to measure tiny variations of the space-time metric, elusive accelerations, and faint forces to test our knowledge of the physical laws ruling the Universe. In space, such instruments can benefit from unique conditions that allow improving both their precision and the signal to be measured. In this paper, we discuss the scientific priorities of a space-based research program in fundamental physics.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Vischi2022,

title = {Possible limits on superconducting quantum computers from spontaneous wave-function collapse models},

author = {Michele Vischi and Luca Ferialdi and Andrea Trombettoni and Angelo Bassi},

doi = {10.1103/physrevb.106.174506},

issn = {2469-9969},

year  = {2022},

date = {2022-11-00},

journal = {Phys. Rev. B},

volume = {106},

number = {17},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Donadi2022,

title = {Seven nonstandard models coupling quantum matter and gravity},

author = {Sandro Donadi and Angelo Bassi},

doi = {10.1116/5.0089318},

issn = {2639-0213},

year  = {2022},

date = {2022-06-01},

volume = {4},

number = {2},

publisher = {American Vacuum Society},

abstract = {We review seven models which consistently couple quantum matter and (Newtonian) gravity in a nonstandard way. For each of them, we present the underlying motivations, the main equations, and, when available, a comparison with experimental data.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Alonso2022,

title = {Cold atoms in space: community workshop summary and proposed road-map},

author = {Alonso, I. and Alpigiani, C. and Altschul, B and Bassi, A.},

doi = {10.1140/epjqt/s40507-022-00147-w},

year  = {2022},

date = {2022-04-12},

urldate = {2022-04-12},

journal = {EPJ Quantum Technology},

volume = {9},

pages = {30},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Carlesso2022,

title = {Present status and future challenges of non-interferometric tests of collapse models},

author = {Matteo Carlesso and Sandro Donadi and Luca Ferialdi and Mauro Paternostro and Hendrik Ulbricht and Angelo Bassi},

doi = {10.1038/s41567-021-01489-5},

issn = {1745-2481},

year  = {2022},

date = {2022-03-00},

journal = {Nat. Phys.},

volume = {18},

number = {3},

pages = {243--250},

publisher = {Springer Science and Business Media LLC},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Belenchia2022,

title = {Quantum physics in space},

author = {Alessio Belenchia and Matteo Carlesso and Ömer Bayraktar and Daniele Dequal and Ivan Derkach and Giulio Gasbarri and Waldemar Herr and Ying Lia Li and Markus Rademacher and Jasminder Sidhu and Daniel K.L. Oi and Stephan T. Seidel and Rainer Kaltenbaek and Christoph Marquardt and Hendrik Ulbricht and Vladyslav C. Usenko and Lisa Wörner and André Xuereb and Mauro Paternostro and Angelo Bassi},

doi = {10.1016/j.physrep.2021.11.004},

issn = {0370-1573},

year  = {2022},

date = {2022-03-00},

journal = {Physics Reports},

volume = {951},

pages = {1--70},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}