



The programme of the conference is as follows, we apologize to any talks not selected, this was due to the very high number of applications: Monday18:00  19:30
 Reception (Hotel Venue The Victoria  William Shakespeare Room, Level 1)

Tuesday09:00 (j)
 Registration
 09:40 (j)
 Welcome Address
 First Joint Session  Chairpersons: Silke Britzen and Angelo Bassi
 10:30 (j)
 Joe Silk  Cosmological Implications of Black Holes  11:30 (j)
 Markus Arndt  Quantum coherence, decoherence and the role of gravity in matterwave experiments with molecules and nanoparticles De Broglie interferometry with macromolecules, clusters and other kinds of nanoparticles explores the boundary between experimentally tested quantum mechanics and classical physics by gradually increasing the size and complexity of objects whose coherent delocalization can still be proven. We will discuss three recent experiments performed in our group at the University of Vienna and how to extrapolate them to masses where gravity starts becoming influential: farfield diffraction of fluorescent molecules at ultrathin gratings demonstrates the waveparticle duality in a particularly conspicuous and didactical way1,2, as it allows to image the stochastic arrival of single molecules in realtime as well the formation of the deterministic ensemble interferogram in the same image. Nearfield interferometry in the KapitzaDiracTalbotLau design has led to the current mass record in quantum delocalization experiments 3,4 with new results emerging. A novel matterwave interferometer that operates with pulsed ionization gratings is being discussed, as it is expected to be best adapted for demonstrating translational quantum coherence for the most massive particles 57.
We will discuss the practical complexity limits of matterwave interferometry, including kinematic effects, phase averaging, decoherence and nonstandard models of quantum mechanics. It turns out that classical gravity and the rotation of the Earth can cause significant dephasing in highmass interferometry with particle beams of finite velocity dispersion. We discuss the relevance of long coherence times and ways to preserve them in a microgravitational environment.
 12:30
 LUNCH
 First afternoon session  Chairperson: Jackson Levi Said  14:00
 Tejinder Singh  Removing time from quantum theory : implications for the measurement problem There are reasons which suggest the existence of an equivalent reformulation of quantum theory which does not refer to time. A consequence is that quantum theory is a limiting case of a stochastic nonlinear theory, with the nonlinearity becoming significant at the Planck mass scale. The nonlinearity can in principle explain why the wavefunction collapses during a measurement. Ongoing and planned experiments can verify or rule out the existence of such a nonlinearity.  14:30
 Omri Gat  Entangled Schroedinger cats in circuit QED Superconducting circuits process quantum information by coupling Josephson junction qubits with electromagnetic modes. Qubitmediated interaction between two modes prepared in highlyexcited coherent states generates twomode entanglement of macroscopically distinct wave packets. We show that the twomode state exhibits two types of entanglement, Belllike and two mode squeezing, and that there is a tradeoff between the degree of entanglement and Bell inequality violation in each entanglement variable. Filtering by weak quadrature measurement produces a superposition of products of squeezed coherent states, that is the CQED version of entangled Schroedinger cats.  15:00
 COFFEE BREAK
 Second afternoon session  Chairperson: Egidijus Norvaisas  15:30
 Nicolas Gisin  Quantum nonlocality based on finitespeed influences leads to signalling The experimental violation of Bell inequalities using spacelike separated measurements precludes the explanation of quantum correlations through causal influences propagating at subluminal speed. Yet, it is always possible, in principle, to explain such experimental violations through models based on hidden influences propagating at a finite speed v>c, provided v is large enough. Here, we show that for any finite speed v>c, such models predict correlations that can be exploited for fasterthanlight communication. This superluminal communication does not require access to any hidden physical quantities, but only the manipulation of measurement devices at the level of our presentday description of quantum experiments. Hence, assuming the impossibility of using quantum nonlocality for superluminal communication, we exclude any possible explanation of quantum correlations in term of finitespeed influences, see arXiv:110.3795.
 16:00  Catalina Oana Curceanu  A glance into the Pandora Box of quantum mechanics: Pauli Exclusion Principle violation and spontaneous collapse models experimental tests In spite of its enormous success, or maybe exactly for this, Quantum Mechanics still hides many mysteries. We shall explore two: the spinstatistics connection and the collapse of the wave function. Experimental undergoing tests of the Pauli Exclusion Principle violation will be discussed, together with future plans to measure the spontaneous emission of X rays predicted in collapse models (CSL). We present a method of searching for possible small violations of the Pauli Exclusion Principle (PEP) for electrons, through the search for "anomalous" Xray transitions in copper atoms, produced by "fresh" electrons (brought inside the copper bar by circulating current) which can have the probability to do the Pauliforbidden transition to the 1 s level already occupied by two electrons. We describe, then, the VIP (VIolation of PEP) experiment which took data at the Gran Sasso underground laboratories, searching for these Pauliprohibited transitions. The goal of VIP is to test the PEP for electrons with unprecedented accuracy, down to a limit in the probability that PEP is violated at the level of 10**29  10**30, improving the previous limit by 34 orders of magnitude. We report achieved experimental results and briefly discuss some of the implications of a possible violation, together with future plans to gain other about 2 orders of magnitude in the estimation of the probability of PEP violation. We will then present an idea to use a similar experimental technique to measure the spontaneously emitted X rays predicted in the framework of collapse models (GRW theory, dynamical reduction models). We shall have a short glimpse into the Pandora’s box of Quantum Mechanics, where – apart of Schrodinger cat – other interesting features might still be hiding.  16:30  Jyrki Piilo  Nonlocal memory effects in the dynamics of open quantum systems We study a model of two entangled photons interacting locally with two dephasing environments. It is shown that initial correlations between the local environments can generate a nonlocal quantum process from a local interaction Hamiltonian. While the global dynamics of the twophoton polarization state exhibits strong memory effects, the induced local dynamics of either of the two photons is found to be Markovian. A direct connection between the degree of memory effects and the amount of correlations in the initial environmental state is derived. The results demonstrate that, contrary to conventional wisdom, enlarging an open system can change the dynamics from Markovian to nonMarkovian.  17:00  END of day one 
WednesdaySecond Joint session  Chairpersons: Silke Britzen and Angelo Bassi  10:00 (j)  GianCarlo Ghirardi  Collapse Theories: a viable solutions to the problems of quantum mechanics A synthetic review of some of the puzzling formal and physical aspects of quantum mechanics which are relevant for the quantum conception of reality, will be presented. In particular attention will be paid to the linear character of the theory and to the phenomenon of entanglement with the related nonlocal aspects. This will offer the opportunity to discuss the measurement problems and to critically review some of the most relevant proposals to overcome it with particular reference to the socalled Collapse Models. A discussion of their general features as well as of the problems they have to face, with specific reference to the relativistic requests, will be presented.  11:00 (j)  Greg Landsberg  TBA  12:00  LUNCH  First afternoon session  Chairperson: Bassano Vacchini  13:30  Andreas Buchleitner  Quantum transport in biological functional units: noise, disorder, structure  14:00  Thomas Durt  Fundamental aspects of Time in Quantum Mechanics and Meson Phenomenology Mesons illustrate fundamental quantum properties such as the superposition principle (for instance in kaon oscillations), and their phenomenology also appeared very useful in the past for measuring CPviolation related effects. More recently, mesons were also useful for testing decoherence and entanglement related effects. The aim of our talk is to show that mesons could also be useful for revealing and/or studying fundamental aspects of Time in the quantum theory, such as the existence of a Time Operator (and also of the socalled Time Superoperator).  14:30  COFFEE BREAK  Second afternoon session  Chairperson: Mario Ziman  15:00  Manfred Niehus  Experimental progress in decoherence studies in free space photonics and optical microfibers We report about the experimental progress we achieved in decoherence studies both in free space and optical microfiber setups, based on polarization entangled photon pairs. In free space, the objective of our work is, at least, to reproduce results achieved recently by other groups, and demonstrating experimentally the transition from Markovian to NonMarkovian dynamics. Concerning optical microfibers, the objective is a proofofconcept to show that these waveguides can be used to manipulate and alter the decoherence dynamics.  15:30  Christos Efthymiopoulos  Chaos in de Broglie  Bohm dynamics and its physical Quantum systems with moving quantum vortices exhibit chaotic behavior of their de Broglie  Bohm trajectories. The dynamical mechanisms behind the appearance of chaos will be presented. However, we find that in many systems chaos is not complete, but there are also many regular de Broglie  Bohm trajectories. This effect poses limitations on the effectiveness of the socalled `quantum relaxation' effect, that has been proposed in order to interpret dynamically the approach of quantum systems to Born's rule. We will discuss quantitative estimates regarding the rate and/or obstructions to relaxation as related to the degree of chaos in quantum systems. We will finally discuss the role of quantum vortices in scattering and diffraction phenomena.  16:00  COFFEE BREAK  Third afternoon session  Chairperson: Sandor Imre  16:30  Jakub Zakrzewski  Extraction of information from dynamics of strongly correlated states An extension of the timedependent Density Matrix Renormalization Group (tDMRG), also known as Time Evolving Block Decimation algorithm (TEBD), allowing for the computation of excited states of onedimensional manybody systems is presented. Its practical use for analyzing the dynamical properties and excitations of the BoseHubbard model describing ultracold atoms loaded in an optical lattice from a~BoseEinstein condensate is shown. This allows for a deeper understanding of nonadiabaticity in experimental realizations of insulating phases  an important aspect for the future prospects of quantum simulators.  17:00  Daniel Sudarsky  The quantum origin of the seeds of cosmic structure and the need for new physics The observations of the first traces of cosmic structure in the Cosmic Microwave Background are in excellent agreement with the predictions of Inflation. However as we shall see, that account is not fully satisfactory, as it does not address the transition from an homogeneous and isotropic early stage to a latter one lacking those symmetries. We will argue that a new aspect of physics must be call upon if we want to account for such transition and that Quantum Gravity might be the place from where this new physics emerges. Moreover we will show that the observations can be used to constrain the various phenomenological proposals made in this regard.  17:30  END of day two  18:00  Bus from conference venue to tour of LMdina and conference dinner, more information on Conference dinner page 
ThursdayThird Joint Session  Chairpersons: Silke Britzen and Angelo Bassi  10:00 (j)  Peter Biermann  TBA  11:00 (j)
 Jean Bricmont  From the microscopic to the macroscopic world and the origin of irreversibility  12:00
 LUNCH
 First afternoon session  Chairperson: Yuji Hasegawa  13:30
 Beatrix Hiesmayr  Revealing Bell's Nonlocality in Particle Physics?! To obtain the whole picture on the phenomenon of entanglement also systems at different energy scales have to be considered. Entangled neutral kaons have turned out to be specially suited to test foundations of quantum mechanics in a way only provided by this system. Only recently a first conclusive experimental test to reveal Bell's nonlocality was found. In the article [Hiesmayr et al., Eur. Phys. J. C (2012) 72:1856] the authors succeeded in deriving a new Bell inequality taking into account the decay property while not spoiling the conclusiveness and, simulataneously, garanteeing its testability. Moreover, the proposed test is experimentally feasible with current technology, e.g. with the KLOE detector at the accelerator facility DAPHNE in Italy.  14:00
 Lajos Diósi  ClassicalQuantum Coexistence: a `Free Will' Test
 14:30
 COFFEE BREAK
 Second afternoon session  Chairperson: Angel Santiago Sanz  15:00
 Giovanni Ciccotti  A pseudoquantum description of (classical) vacancy diffusion in crystals We introduce an observable field to describe the dynamics of a single vacancy in a crystal. This field is the density of a pseudo quantum wavefunction representing the vacancy, which, in turn, is the ground state eigenfunction of an Hamiltonian associated to the potential energy field generated by the atoms in the sample. In our description, the $\hbar^2/2 m$ coefficient of the kinetic energy term is a tunable parameter that makes the density localized in the regions of relevant minima of the potential energy field. Based on this description, we derive a set of collective variables that we use in rare event simulations to identify the vacancy diffusion paths in a 2D crystal. Our simulations reveal, in addition to the simple and expected nearest neighbor hopping path, collective migration mechanisms of the vacancy. These mechanisms involve several lattice sites and produce a long range migration. Finally, we also observed a vacancy induced crystal reorientation process.  15:30
 Ward Struyve  Semiclassical approximations based on the de BroglieBohm theory
 16:00
 COFFEE BREAK
 Third afternoon session  Chairperson: GheorgheSorin Paraoanu  16:30
 Marco Genovese  Recent experimental progresses in testing Quantum Mechanics Quantum Mechanics represents nowadays one of the pillars of modern physics: so far a huge amount of theoretical predictions deriving from this theory has been confirmed by very accurate experimental data, while the theory is at the basis of a large spectrum of researches ranging from solid state physics to cosmology, from biophysics to particle physics. Furthermore, in the last years the possibility of manipulating single quantum states has fostered the development of promising quantum technologies as quantum information (calculus, communication, etc.), quantum metrology, quantum imaging, ...
Nevertheless, even after a pluridecennial debate many problems related to the foundations of this theory persist, like nonlocal effects of entangled states, wave function reduction and the concept of measurement in Quantum Mechanics, the transition from a microscopic probabilistic world to a macroscopic deterministic world described by classical mechanics (macroobjectivation) and so on. Problems that, beyond their fundamental interest in basic science, now also concern the impact of these developing technologies.
In this talk, after a short summary of the present discussion concerning some of these problems, we present some recent experimental works in the field.
In particular, some specific experiment realized at INRIM will be described in some detail (concerning tests of specific local realistic models, wave particle duality, …). The first experiment to be described regards the testing of two specific, restricted local realistic models, properly built for experiments with entangled photons; the interesting feature of these models is the fact that they are free from the detection loophole, thus they don’t rely on the fair sampling assumption (the quantum efficiency of the system plays a role in the inequalities built for these models). The experimental data collected violated these inequalities, showing instead a perfect agreement with Quantum Mechanics predictions. The second one is a nonclassicality test at the single particle level.  17:00
 Spiros Skourtis  Biological electron transport processes Electron transfer reactions are ubiquitous in biology. Biological electron transfer mechanisms range from tunnelling to thermally activated hopping. Due to the nature of biomolecules, molecular motion (structural fluctuations) is an important determinant of the electron transfer rate. I give a brief introduction to the theory and simulation of biological electron transfer rates and discuss similarities between biological electron transfer and small molecule /molecular wire electron transport mechanisms. In the final part of the talk I discuss recent work about the control of electron transport in biological and small molecule devices.  17:30
 END of day three

FridayFirst morning session  Chairperson: Beatrix Hiesmayr
 10:00  Salvador MiretArtés  Quantum (Bohmian) Stochastic Trajectories Stochasticity plays an imprtant role in many problem found in classical and quantum mechanics. Here we would like to introduce, in a simple way, the concept of quantum (Bohmian) stochastic trajectory by analyzing the free evolution of one and two wave packets in presence of a flat surface considered as a thermal bath. Decoherence and the Zeno effect will also be discussed.  10:30
 Irene Burghardt  Hierarchical effectivemode decomposition for nonMarkovian quantum environments This talk summarizes our recent developments of reduceddimensional representations of nonMarkovian environments, based upon the construction of Mori type effective mode chains [13]. The sequences of coupled effective modes, which are generated by suitable coordinate transformations from spinboson type models, absorb the cumulative effects of the systembath coupling and can be shown to sequentially resolve the dynamics as a function of time. Truncation of the chains at successive orders generates a family of approximate spectral densities which approach the true spectral density with increasing accuracy [1,3]. Convergence can be explicitly demonstrated in terms of the properties of the residual spectral densities which approach a quasiOhmic limit [3]. Overall, the approach provides a very general strategy for the embedding of nonMarkovian environments into an enlarged set of variables. An extension to correlated environmental fluctuations is straightforward. Applications are presented for nonadiabatic dynamics and excitation energy transfer in extended molecular systems [2]. Here, decoherence is typically found to set in with a delay, beyond the shortest time scale which is determined by few effective modes.
[1] K. H. Hughes, C. D. Christ, I. Burghardt, J. Chem. Phys. 131, 024109 (2009); ibid. 131, 124108 (2009). [2] H. Tamura, J. G. S. Ramon, E. R. Bittner, I. Burghardt, Phys. Rev. Lett. 100, 107402 (2008), H. Tamura, I. Burghardt, M. Tsukada, J. Phys. Chem. C 115, 9237 (2011). [3] R. Martinazzo, B. Vacchini, K. H. Hughes, I. Burghardt, J. Chem. Phys. 134, 011101 (2011), R. Martinazzo, K. H. Hughes, I. Burghardt, Phys. Rev. E 84, 030102(R) (2011).  11:00
 COFFEE BREAK  Second Morning session  Chairperson: Petros Wallden  11:30
 Yuji Hasegawa  Uncertain relation studied in neutron’s successive spinmeasurements The uncertainty principle is certainly one of the most famous and important aspects of quantum mechanics: Heisenberg first suggested a limitation of joint measurements of canonically conjugate variables due to the back action of measurement. However, known rigorous proofs justify the prediction, that the product of the measurement error and disturbance caused by the measurement is not less than a bound set by the commutator, only under limited circumstances. Recently a universally valid relation between the error and the disturbance has derived by Ozawa. In this talk, a neutron optical experiment is reported that measures the error of a spincomponent measurement and the disturbance caused on another spincomponent measurement. The experimental results exhibit that the error and the disturbance completely obey the new relation but violated the old one in a wide range of experimental parameters. The solution of a longstanding problem to describe the relation between the measurement accuracy and the disturbance caused by that measurement is discussed.  12:00
 LUNCH
 First afternoon session  Chairperson: Catalina Curceanu  13:30
 André Xuereb  Quantum mechanics at the mesoscale The past decade has seen the field of optomechanics, the use of light to control the motion of mechanics at the microscale, steadily gaining traction. Recent progress hints that experiments may soon start moving away from proofs of principle and towards tests of quantum mechanics at larger and larger mass scales. involving, e.g., mechanical Schrödinger cats, or entangled states of a mirror with a light field.
In this talk I will briefly introduce the main theoretical tools that are used in the description of optomechanical systems, and then go on to discuss some of our recent work dealing with the possibility of observing genuine multipartite entanglement between light fields and mesoscopic mechanical oscillators in experimentallyaccessible systems.  14:00
 Adrian Kent  The Quantum Landscape I describe new classes of generalizations of the quantum theory of a closed system that make testably different predictions from standard quantum theory, and examine the theoretical and experimental implications.  14:30
 COFFEE BREAK
 Second afternoon session  Chairperson: Daniel Braun  15:00
 Antonio Di Domenico  The Quantum Mechanics and discrete symmetries of neutral K mesons The neutral kaon doublet is one of the most intriguing systems in nature. Entangled pairs of neutral K mesons produced in φ decays offers a unique possibility to perform very precise tests of fundamental discrete symmetries in nature, as well as of basic principles of quantum mechanics.The most recent results will be reviewed and perspectives in the field will be discussed.  15:30
 Nikola Buric  Emergence of classical systems from constrained quantum background. Coarsegrained description of a quantum system is mathematically described as a constrained Hamiltonian dynamics. It is seen that the evolution of properly coarsegrained systems preserves constant and minimal quantum fluctuations of the fundamental observables. This leads to the emergence of the corresponding classical system on a sufficiently large scale. The procedure is utilized to establish a consistent description of hybrid quantumclassical systems. Dynamics of the quantum measurement process is discussed as a relevant example.  16:00
 COFFEE BREAK
 Third afternoon session  Chairperson: Angelo Bassi  16:30
 Thomas Filk  A Chain of Coupled Pendula Leading to Quantum Relativity Any conceptually closed quantum theory which addresses the problem of a quantized spacetime structure faces the task of including ``rulers'' and ``clocks'' as dynamical subsystems. In view of this challenge, the SineGordon theory can serve as a nontrivial toy model with many profound features:
1) The classical (nonquantum) SineGordon theory can be formulated as the continuum limit of a chain of pendula, i.e., as a Newtonian system which in the continuum limit becomes Lorentz invariant. 2.) The nontrivial solutions of the SineGordon equation  solitons and breathers  can serve as intrinsic measures for spatial and temporal distances. The transition from extrinsic measures (used by an external, Newtonian observer) to intrinsic measures (the widths of solitons and the periods of breathers) corresponds to the transition from the Lorentz invariant Newtonian theory (the chain of coupled pendula in the continuum limit) to an intrinsically relativistic (Minkowski) structure of space and time. 3.) As the SineGordon theory is integrable both as a classical theory as well as a quantum theory (using classical and quantum inverse scattering methods), many of the nontrivial concepts related to dynamical rulers and clocks can be studied explicitly.
The first part of my talk will describe the transition from the chain of coupled pendula to a relativistic theory and the relevance of solitons and breathers in the physical interpretation of this transition. The second part will be an introduction to the quantum properties of the SineGordon theory as well as some speculative ideas about the role of ``quantum clocks'' and ``quantum rulers'' in a complete theory of quantum spacetime.  17:00
 Egidijus Norvaisas  Selfconsistent canonically quantized SU(3) Skyrme Model for Baryons The traditional approach is to consider SU(3) Skyrme model semiclassically as a rigid quantum rotator with the profile function being fixed by the classical solution of the SU(2) Skyrme model. In this work the canonical quantization of the model is performed in terms of the collective coordinate formalism and leads to the establishment of a purely quantum corrections of the model. These new corrections are of a fundamental importance. They are crucial in obtaining stable solitonic solutions of the quantum SU(3) Skyrme model, thus making the model selfconsistent. The canonical quantization realize the T.H.R. Skyrme‘s conjecture that „mass may arise as a selfcosistent quantal effect“. Such treatment of the model conversely to the semiclassical case leads to a family of the stable solitonic solutions that describe the baryon octet and the decuplet and reproduces the experimental values of their masses and other physical parameters.  17:30
 Concluding remarks  18:00
 END of conference  (j)  Common session with Black Hole conference
This will be included in the welcome pack along with an information pack available here.
30 July 2021
https://www.um.edu.mt/events/issaconferences/quantummalta2012/programme



