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The interaction between particles and the electromagnetic field induces decoherence generating a small suppression of fringes in an interference experiment. We show that if a double slit-like experiment is performed in the vicinity of a conducting plane, the fringe visibility depends on the position (and orientation) of the experiment relative to the conductor's plane. This phenomenon is due to the change in the structure of vacuum induced by the conductor and is closely related to the Casimir effect. We estimate the fringe visibility both for charged and for neutral particles with a permanent dipole moment. The presence of the conductor may tend to increase decoherence in some cases and to reduce it in others. A simple explanation for this peculiar behavior is presented.The interaction of a quantum system with its environment is responsible for the process of decoherence, which is one of the main ingredients to understand the quantum-classical transition [1]. In some cases, the interaction with the environment cannot be switched off. This is the case for charged particles that unavoidably interact with the electromagnetic field. As this interaction is fundamental, its effect is present in any interference experiment. In this letter we will analyze the influence of a conducting boundary in the decay of the visibility of interference fringes in a double slit experiment performed with charged particles (or neutral particles with a dipole moment). The reduction of fringe visibility is induced by the interaction between the particles and the electromagnetic field. Some aspects of this problem have been analyzed before. In fact, it is known that for charged particles, the interaction between the system (the particle) and the environment (the electromagnetic field) induces a rather small decoherence effect even if the initial state of the field is the vacuum [2,3,4,5,6,7,8]. A particularly simple expression for the decay in the fringe visibility was obtained in [2,3]: Assuming an electron in harmonic motion (with frequency Ω) along the relevant trajectories of the double slit experiment, the fringe visibility decays by a factor (1− P ) 2 where P is the probability that a dipole p = eR oscillating at frequency Ω emits a photon (R is the characteristic size of the trajectory). This result is in accordance with the idea that decoherence becomes effective when a record of the state of the system is irreversibly imprinted in the environment. In this case, after photon emission, if the electron follows the trajectory X 1 (t) of the double slit experiment (see Figure 1) it becomes correlated with a state of the environment |E 1 (t) . This state is different from the one with which the electron correlates if it follows the trajectory X 2 (t). The absolute value of the overlap between these two different states is precisely given by (1 − P )2 .In this letter we will analyze how the fringe visibility is modified when performing a double slit interference experiment in the vicinity of a conducting plane. Our analysis will serve ...

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Washing machines have in recent years incorporated programmes that are very energy-and waterefficient, but this entails a long programme duration, often beyond 4 h. These are also the programmes that the manufactures use to define, test and declare the overall water and energy efficiency of the machines. In response to these developments, there is evidence that consumers are reluctant to use excessively lengthy programmes, even if they are aware that the programmes are more energy-efficient.This paper analyses this divergence of programme offer and programme use, which jeopardises the energy efficiency policy objectives for these appliances in the European Union (EU). The paper explores several policy measures to address this divergence, discussed in the context of the revision of the Ecodesign and Energy Labelling regulations that apply to washing machines in the EU.Three different measures are studied: the provision of information about the programme duration on the energy label, the inclusion of time as an intrinsic parameter of the energy efficiency index calculations and the setting of a programme duration cap.The paper concludes that introducing programme duration as an additional parameter of the energy efficiency index would result in the highest energy savings. However, this scenario is associated with significant uncertainties since competition among the manufacturers for a better energy label classification will not solely focus on energy efficiency aspects, and the outcome of such competition is unclear. The other two measures investigated are less effective but would also deliver savings. A programme duration cap would bring energy savings if consumers are aware of their existence and select the now shorter yet energy-efficient programmes more often. The provision of programme duration information on the energy label would also be effective but requires that consumers are able to correctly understand it.

From an enactive perspective, one should be able to explain how perception and actions, constituted in patterns of interactions with the world, evolve into the capacities for social coordination and social understanding distinctive of human beings. Traditional accounts of our social understanding skills, focusing on the role of intentionality as the ''aboutness'' associated with the use of symbolic language, make this sort of explanation difficult to articulate. A satisfactory explanation should start with the recognition that intentionality is not a monolithic phenomenon and that more basic kinds of intentionality embodied in material culture have played a crucial role in allowing for the complexity of human social cognition. We argue for the importance of kinds of bottom-up intentionality, which arise from the world as it is experienced, dynamically structuring and directing our cognitive capacities toward possibilities of (joint) action. Musicality (our capacity for being musical) is a particularly rich kind of cultural expression, in which intentionality embodied in material culture can be studied and its significance for the structure of our deeply social cognition can be explored.