Toward an architecture for quantum programming

It is becoming increasingly clear that, if a useful device for quantum computation will ever be built, it will be embodied by a classical computing machine with control over a truly quantum subsystem, this apparatus performing a mixture of classical and quantum computation. This paper investigates a possible approach to the problem of programming such machines: a template high level quantum language is presented which complements a generic general purpose classical language with a set of quantum primitives. The underlying scheme involves a run-time environment which calculates the byte-code for the quantum operations and pipes it to a quantum device controller or to a simulator. This language can compactly express existing quantum algorithms and reduce them to sequences of elementary operations; it also easily lends itself to automatic, hardware independent, circuit simplification. A publicly available preliminary implementation of the proposed ideas has been realized using the C++ language.Comment: 23 pages, 5 figures, A4paper. Final version accepted by EJPD ("swap" replaced by "invert" for Qops). Preliminary implementation available at: http://sra.itc.it/people/serafini/quantum-computing/qlang.htm

On the optimality of individual entangling-probe attacks against BB84 quantum key distribution

It is shown that an existing method to study ideal individual attacks on the BB84 QKD protocol using error discard can be adapted to reconciliation with error correction, and that an optimal attack can be explicitly found. Moreover, this attack fills Luetkenhaus bound, independently of whether error positions are leaked to Eve, proving that it is tight. In addition, we clarify why the existence of such optimal attacks is not in contradiction with the established ``old-style'' theory of BB84 individual attacks, as incorrectly suggested recently in a news feature.Comment: 12 pages, 3 figure

Coping with the inheritance of COVID-19: the role of new interactive technologies to enhance user experience in different contexts of use

The COVID-19 pandemic has upset the habits of people and various sectors of society, including training, entertainment, and retail. These sectors have been forced to adapt to abnormal situations such as social distancing, remote work, and online entertainment. The pandemic has significantly transformed the training field, leading to the closure of many in-person instruction centers and a shift toward online education courses, which can be less effective. In addition, the entertainment industry has been heavily transformed by social distancing, resulting in the cancellation of many live events and the closure of several cinemas. This has increased demand for online entertainment options, such as streaming services and virtual events. Finally, the restrictions imposed by the COVID-19 pandemic substantially impacted physical stores and fairs, suspending exhibitions for more than two years. This has further driven consumers to rely on e-commerce to fulfill their purchasing and companies to increasingly take advantage of new technologies such as augmented reality. In this suddenly disrupted scenario, new technologies have the potential to fill the gap generated by the pandemic, functioning as an interactive bridge to connect people. This Ph.D. thesis explored the potential of interactive technologies in mitigating the challenges posed by the COVID-19 pandemic in various contexts of use in the above-mentioned areas. Specifically, three lines of research were investigated by conducting different studies using a mixed approach in the Human-Computer Interaction field. The first research line focused on the study of immersive virtual reality training, with a particular interest in flood emergencies, a growing phenomenon. The goal was to implement engaging and efficient training for citizens that live near rivers through a human-centric design approach. The second line of research explored innovative ways to improve social interaction and collaboration in the entertainment sector, highlighting guidelines for the design of shared streaming experiences. In particular, three different communication modalities were studied during group viewing of an interactive film on a streaming platform. Finally, the third research line focused on the retail sector. On the one hand, the focus consisted of understanding which aspects of the 3D web and AR technology are helpful for supporting small businesses and trade fairs. On the other hand, the focus was to investigate how to support consumers during an AR shopping experience when interacting with 3D virtual products of different sizes. Overall, this project provides suggestions and guidelines for designing systems that can both increasingly connect people at a distance and offer new hybrid worlds. In addition, this project expands state-of-the-art related to interactive technologies and offers generalizable results outside the crisis created by COVID-19. These technologies, now increasingly integrated into everyday life, can be a tool for empowerment and resilience, improving people's lives.The COVID-19 pandemic has upset the habits of people and various sectors of society, including training, entertainment, and retail. These sectors have been forced to adapt to abnormal situations such as social distancing, remote work, and online entertainment. The pandemic has significantly transformed the training field, leading to the closure of many in-person instruction centers and a shift toward online education courses, which can be less effective. In addition, the entertainment industry has been heavily transformed by social distancing, resulting in the cancellation of many live events and the closure of several cinemas. This has increased demand for online entertainment options, such as streaming services and virtual events. Finally, the restrictions imposed by the COVID-19 pandemic substantially impacted physical stores and fairs, suspending exhibitions for more than two years. This has further driven consumers to rely on e-commerce to fulfill their purchasing and companies to increasingly take advantage of new technologies such as augmented reality. In this suddenly disrupted scenario, new technologies have the potential to fill the gap generated by the pandemic, functioning as an interactive bridge to connect people. This Ph.D. thesis explored the potential of interactive technologies in mitigating the challenges posed by the COVID-19 pandemic in various contexts of use in the above-mentioned areas. Specifically, three lines of research were investigated by conducting different studies using a mixed approach in the Human-Computer Interaction field. The first research line focused on the study of immersive virtual reality training, with a particular interest in flood emergencies, a growing phenomenon. The goal was to implement engaging and efficient training for citizens that live near rivers through a human-centric design approach. The second line of research explored innovative ways to improve social interaction and collaboration in the entertainment sector, highlighting guidelines for the design of shared streaming experiences. In particular, three different communication modalities were studied during group viewing of an interactive film on a streaming platform. Finally, the third research line focused on the retail sector. On the one hand, the focus consisted of understanding which aspects of the 3D web and AR technology are helpful for supporting small businesses and trade fairs. On the other hand, the focus was to investigate how to support consumers during an AR shopping experience when interacting with 3D virtual products of different sizes. Overall, this project provides suggestions and guidelines for designing systems that can both increasingly connect people at a distance and offer new hybrid worlds. In addition, this project expands state-of-the-art related to interactive technologies and offers generalizable results outside the crisis created by COVID-19. These technologies, now increasingly integrated into everyday life, can be a tool for empowerment and resilience, improving people's lives

Internal structure and tectonic evolution of an underthrust tectonic m\ue9lange: the Sestola-Vidiciatico tectonic unit of the Northern Apennines, Italy

The Sestola-Vidiciatico Tectonic Unit (SVTU) in the Northern Apennines is an underthrust tectonic melange presently sandwiched between the Tuscan-Umbrian foredeep units and the overlying Ligurian/Subligurian thrust-nappe. The SVTU has been generated during the collision between the European and the Adria plates and now it separates the former oceanic accretionary wedge -Ligurian/Subligurian thrust nappe-from the underlying fold-and-thrust belt formed by Adria sedimentary units. The collision caused an eastward migrating foredeep basin and the overthrusting of the frontal part of the Ligurian/Subligurian thrust-nappe on the subducting Adria margin. Part of the inner lower-slope sediments of the migrating foredeep basin have been unconformably deposited on a frontal prism formed by material already accreted in the Ligurian/Subligurian prism gravitationally and tectonically reworked. The frontal prism and its sedimentary cover have been progressively dragged down along the plate boundary zone generating the SVTU. The lower-slope sediments have been incorporated in the melange as they were not completely lithified, and they show a long deformation history ranging from continuous and pervasive soft-sediment deformation to discontinuous brittle deformation concentrated along faults and mainly controlled by cycles of fluid pressure as testified by the presence of crack-and-seal texture and implosion breccia in the veins

A lambda calculus for quantum computation with classical control

The objective of this paper is to develop a functional programming language for quantum computers. We develop a lambda calculus for the classical control model, following the first author's work on quantum flow-charts. We define a call-by-value operational semantics, and we give a type system using affine intuitionistic linear logic. The main results of this paper are the safety properties of the language and the development of a type inference algorithm.Comment: 15 pages, submitted to TLCA'05. Note: this is basically the work done during the first author master, his thesis can be found on his webpage. Modifications: almost everything reformulated; recursion removed since the way it was stated didn't satisfy lemma 11; type inference algorithm added; example of an implementation of quantum teleportation adde

IL-12– and IL-23–induced T helper cell subsets: birds of the same feather flock together

Traditionally, CD4+ T cells have been separated into two different subsets named T helper (Th)1 and Th2. A new IL-23–driven subset of Th cells called ThIL-17 has now been described. The data suggest that IL-23 plays an important role in the differentiation of autoreactive pathogenic T cells. Whether these IL-23–induced ThIL-17 cells are a unique subset or are related to other Th subsets is discussed