Foams in contact with solid boundaries: equilibrium conditions and conformal invariance

A liquid foam in contact with a solid surface forms a two-dimensional foam on the surface. We derive the equilibrium equations for this 2D foam when the solid surface is curved and smooth, generalising the standard case of flat Hele Shaw cells. The equilibrium conditions at the vertices in 2D, at the edges in 3D, are invariant by conformal transformations. Regarding the films, conformal invariance only holds with restrictions, which we explicit for 3D and flat 2D foams. Considering foams confined in thin interstices between two non parallel plates, normal incidence and Laplace's law lead to an approximate equation relating the plate profile to the conformal map. Solutions are given for the logarithm and power laws in the case of constant pressure. The paper concludes on a comparison with available experimental data.Comment: 10 pages, 7 figure

Deformed versus undeformed cat states encoding qubit

We study the possibility of exploiting superpositions of coherent states to encode qubit. A comparison between the use of deformed and undeformed bosonic algebra is made in connection with the amplitude damping errors.Comment: 6 pages, 2 eps figures, to appear in J. Opt.

Reconstructing the density operator by using generalized field quadratures

The Wigner function for one and two-mode quantum systems is explicitely expressed in terms of the marginal distribution for the generic linearly transformed quadratures. Then, also the density operator of those systems is written in terms of the marginal distribution of these quadratures. Some examples to apply this formalism, and a reduction to the usual optical homodyne tomography are considered.Comment: 17 pages, Latex,accepted by Quantum and Semiclassical Optic

Motional Squashed States

We show that by using a feedback loop it is possible to reduce the fluctuations in one quadrature of the vibrational degree of freedom of a trapped ion below the quantum limit. The stationary state is not a proper squeezed state, but rather a ``squashed'' state, since the uncertainty in the orthogonal quadrature, which is larger than the standard quantum limit, is unaffected by the feedback action.Comment: 8 pages, 2 figures, to appear in the special Issue "Quantum Correlations and Fluctuations" of J. Opt.

Quantum State Reconstruction of a Bose-Einstein Condensate

We propose a tomographic scheme to reconstruct the quantum state of a Bose-Einstein condensate, exploiting the radiation field as a probe and considering the atomic internal degrees of freedom. The density matrix in the number state basis can be directly retrieved from the atom counting probabilities.Comment: 11 pages, LaTeX file, no figures, to appear in Europhysics Letter

Synthesis and characterization of entangled mesoscopic superpositions for a trapped electron

We propose a scheme for the generation and reconstruction of entangled states between the internal and external (motional) degrees of freedom of a trapped electron. Such states also exhibit quantum coherence at a mesoscopic level.Comment: 4 pages, 1 figure, RevTeX (twocolumn

To what extent are consumers' perception and acceptance of alternative meat production systems affected by information? The case of cultured meat

Meat grown in labs, also known as cultured meat, is currently under development and will likely soon be available on supermarket shelves. Such new meat-based products may tackle some of the most controversial societal concerns related to the industry, in particular animal wellbeing and environmental impacts, with further potential improvements concerning food security. However, due to its high degree of novelty, it remains unclear how consumers view this type of food product, particularly in terms of beliefs regarding its intrinsic attributes such as safety, nutrients and flavor characterization, and its positive externalities concerning the environment, animal welfare, and food security. The present study aims at unveiling the perception, acceptance, and willingness to try, buy, and pay a premium price for cultured meat in the Italian context, deconvoluting the effect of providing positive information to consumers. Such investigation offers new insights for the development of targeted marketing strategies by deepening the understanding of consumers' perception of this lab-grown food product. Indeed, the study reveals that positive information affects the consumers' perception towards safety and nutritional characteristics of cultured meat and the willingness to pay a premium price for this new food product accordingly. The global meat production system is currently under pressure, particularly for its environmental and animal wellbeing impacts, as well as for the increasing protein demand worldwide. In this regard, cultured meat is currently a hot topic in the industrial, political, and societal arenas, revealing itself as the potential relief for the issues above. However, its high degree of novelty may hamper the extent of consumers' acceptance. This research assesses for which beliefs concerning intrinsic attributes and positive externalities, the provision of information is a sufficient tool for affecting the perception and acceptance of cultured meat on a panel of Italian consumers. Changes in perception and willingness to try, buy, and pay are assessed by measuring the variation before and after the provision of positive information related to the product. The results show that perception is affected by positive information concerning safety and nutritional characteristics, whereas the opposite occurs regarding the product flavor. Furthermore, findings reveal that, while the willingness to buy increases after providing positive information, the willingness to try does not. Finally, information on intrinsic attributes and positive externalities of the cultured meat would have to be combined with different approaches for further enhancement of consumers' perception and acceptance

Decorated vertices with 3-edged cells in 2D foams: exact solutions and properties

The energy, area and excess energy of a decorated vertex in a 2D foam are calculated. The general shape of the vertex and its decoration are described analytically by a reference pattern mapped by a parametric Moebius transformation. A single parameter of control allows to describe, in a common framework, different types of decorations, by liquid triangles or 3-sided bubbles, and other non-conventional cells. A solution is proposed to explain the stability threshold in the flower problem.Comment: 13 pages, 17 figure

Beyond the Standard "Marginalizations" of Wigner Function

We discuss the problem of finding "marginal" distributions within different tomographic approaches to quantum state measurement, and we establish analytical connections among them.Comment: 12 pages, LaTex, no figures, to appear in Quantum and Semiclass. Op