839 research outputs found

    A Proposal for the Classical Limit in Bohm's Theory

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    In this paper, I describe a general strategy for deriving Newtonian mechanics from Bohm’s theory in the classical macroscopic regime. The strategy is based on two main steps: (i) the use of open systems, leading to the formation of independent subsystems; (ii) the analysis of the quantum potential for the emergent subsystems. The first step leads to and explains (within the Bohmian framework) the well-known phenomenon of decoherence. The second one provides a precise criterion for the emergence of Newtonian trajectories. In particular, I will show that, under reasonable classicality conditions, the quantum potential of the emergent subsystems become negligible and, consequently, they will follow an approximately Newtonian dynamics

    Multi-field and Bohm’s theory

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    In the recent literature, it has been shown that the wave function in the de Broglie–Bohm theory can be regarded as a new kind of field, i.e., a "multi-field", in three-dimensional space. In this paper, I argue that the natural framework for the multi-field is the original second-order Bohm’s theory. In this context, it is possible: i) to construe the multi-field as a real-valued scalar field; ii) to explain the physical interaction between the multi-field and the Bohmian particles; and iii) to clarify the status of the energy-momentum conservation and the dynamics of the theory

    Electronic system for drift clock calculation and synchronization for seafloor observatory

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    The paper describes a new electronic device that allows an easily measurement of the drift between a reference time source (usually GPS) and an atomic rubidium clock which is normally used in seafloor observatories. The Rubidium clock is used in autonomous seafloor observatories to supply reference time for data acquisition with the precision of milliseconds. During the deployment of seafloor observatory the clock is synchronized with GPS. It is critical to evaluate the time drift between the clock and the GPS, when the observatory is recovered. In fact, thanks to an accurate drift measurement it’s possible to have a correct timestamp for data series collected by seafloor observatory’s instruments. The device described in this paper is composed by an Arduino mega shield integrated with other electronic circuits. The device is easily customizable for different clocks in fact Arduino IDE allows development of the desired features for the rubidium clock used in the specific application.Peer Reviewe

    The Wave-Function Is a Multi-Field

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    It is generally argued that if the wave-function in the de Broglie--Bohm theory is a physical field, it must be a field in configuration space. Nevertheless, it is possible to interpret the wave-function as a multi-field in three-dimensional space. This approach hasn't received the attention yet it really deserves. The aim of this paper is threefold: first, we show that the wave-function is naturally and straightforwardly construed as a multi-field; second, we show why this interpretation is superior to other field interpretations; third, we clarify common misconceptions

    The Wave-Function Is a Multi-Field

    Get PDF
    It is generally argued that if the wave-function in the de Broglie--Bohm theory is a physical field, it must be a field in configuration space. Nevertheless, it is possible to interpret the wave-function as a multi-field in three-dimensional space. This approach hasn't received the attention yet it really deserves. The aim of this paper is threefold: first, we show that the wave-function is naturally and straightforwardly construed as a multi-field; second, we show why this interpretation is superior to other field interpretations; third, we clarify common misconceptions

    The Wave-Function Is a Multi-Field

    Get PDF
    It is generally argued that if the wave-function in the de Broglie--Bohm theory is a physical field, it must be a field in configuration space. Nevertheless, it is possible to interpret the wave-function as a multi-field in three-dimensional space. This approach hasn't received the attention yet it really deserves. The aim of this paper is threefold: first, we show that the wave-function is naturally and straightforwardly construed as a multi-field; second, we show why this interpretation is superior to other field interpretations; third, we clarify common misconceptions

    COVID-19 AdenoviralVector Vaccine and Central Retinal Vein Occlusion

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    Purpose: The purpose of this article is to report a case of sudden onset ischemic retinal central vein occlusion after a second dose of COVID-19 adenoviral vector vaccine.Case report/observations: A 54-year-old woman with systemic arterial hypertension developed ischemic central retinal vein occlusion in her right eye on day 2 after the second dose of COVID-19 adenoviral vector vaccine ChAdOx1 nCoV-19/AZD1222, Oxford-AstraZeneca.Conclusion: Adenoviral vector vaccine promotes both cellular and humoral immune responses, increasing the level of inflammatory cytokines. These cytokines are the same implied in the possible pathogenesis of central retinal vein occlusion. Subsequently, we recommend informing patients at risk of possible ocular adverse events, which require urgent evaluation

    A decoherence-based approach to the classical limit in Bohm's theory

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    The paper explains why the de Broglie-Bohm theory reduces to Newtonian mechanics in the macroscopic classical limit. The quantum-to-classical transition is based on three steps: (i) interaction with the environment produces effectively factorized states, leading to the formation of effective wave functions and hence decoherence; (ii) the effective wave functions selected by the environment–the pointer states of decoherence theory–will be well-localized wave packets, typically Gaussian states; (iii) the quantum potential of a Gaussian state becomes negligible under standard classicality conditions; therefore, the effective wave function will move according to Newtonian mechanics in the correct classical limit. As a result, a Bohmian system in interaction with the environment will be described by an effective Gaussian state and–when the system is macroscopic–it will move according to Newtonian mechanics
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