The Experts below are selected from a list of 66294 Experts worldwide ranked by ideXlab platform
Igor Lesanovsky - One of the best experts on this subject based on the ideXlab platform.
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engineering nonbinary rydberg interactions via phonons in an optical lattice
Physical Review Letters, 2020Co-Authors: F M Gambetta, F Schmidtkaler, Igor LesanovskyAbstract:Coupling electronic and vibrational degrees of freedom of Rydberg atoms held in optical tweezer arrays offers a Flexible Mechanism for creating and controlling atom-atom interactions. We find that the state-dependent coupling between Rydberg atoms and local oscillator modes gives rise to two- and three-body interactions which are controllable through the strength of the local confinement. This approach even permits the cancellation of two-body terms such that three-body interactions become dominant. We analyze the structure of these interactions on two-dimensional bipartite lattice geometries and explore the impact of three-body interactions on system ground state on a square lattice. Focusing specifically on a system of ^{87}Rb atoms, we show that the effects of the multibody interactions can be maximized via a tailored dressed potential within a trapping frequency range of the order of a few hundred kilohertz and for temperatures corresponding to a >90% occupation of the atomic vibrational ground state. These parameters, as well as the multibody induced timescales, are compatible with state-of-the-art arrays of optical tweezers. Our work shows a highly versatile handle for engineering multibody interactions of quantum many-body systems in most recent manifestations on Rydberg lattice quantum simulators.
D B Doan - One of the best experts on this subject based on the ideXlab platform.
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rigid and Flexible joint modelling in multibody dynamics using finite elements
Computer Methods in Applied Mechanics and Engineering, 1991Co-Authors: Alberto Cardona, Michel Geradin, D B DoanAbstract:Abstract This paper presents a finite element formulation of mechanical joints for multibody dynamics. The augmented Lagrangian procedure is used to express constraints of both holonomic and non-holonomic types. The method is first demonstrated on the holonomic case of the hinge joint. It is then used to develop a wheel capable of radial deformation, slipping, breaking and coupled lateral/torsional deformations. Both joints are formulated with the objective of being integrated into a multiple purpose finite element software for Flexible Mechanism analysis. Two application examples are presented to demonstrate the effectiveness of the method: the dynamic deployment of a curved reflector in space and the simulation of a nose landing gear during touch-down.
Richard S J Tol - One of the best experts on this subject based on the ideXlab platform.
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unilateral regulation of bilateral trade in greenhouse gas emission permits
Ecological Economics, 2005Co-Authors: Katrin Rehdanz, Richard S J TolAbstract:This paper considers the coordination of domestic markets for tradable emission permits where countries determine their own emission reduction targets, using a two-country model. Linking such schemes is beneficial to both countries but may cause the exporting country to decrease its emission reduction target and export more permits. This in turn would not only reduce the costs for both countries as less emissions have to be reduced, but it also lowers the environmental benefits of the importing country. One price instrument (tariff) and two quantity instruments (discount, quota) to prevent the exporting country from issuing more permits are examined. Each instrument restricts trade and alters the terms of trade for the two countries. The importing country (and regulator) prefers an import tariff and an import quota to a carbon discount. If the exporting country releases additional permits, the importing country should not try to keep total emissions constant, as that would be ineffective and maybe even counterproductive. Instead, the importing country should aim to keep the total import constant; this would impose costs on the exporting country that are independent of the policy instrument; an import quota would be the cheapest option for the importing country. An import quota would also stress the idea of supplementary of the Flexible Mechanism as it increases the share of emissions reduced domestically. Compliance and liability issues constrain the market further. However, both the importing and the exporting country would prefer that the permit seller is liable in case of non-compliance, as sellers' liability would less constrain the market.
Axel Cleeremans - One of the best experts on this subject based on the ideXlab platform.
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comparing self and hetero metacognition in the absence of verbal communication
PLOS ONE, 2020Co-Authors: Laurene Vuillaume, Jeanremy Martin, Jerome Sackur, Axel CleeremansAbstract:The ability to infer how confident other people are in their decisions is crucial for regulating social interactions. In many cooperative situations, verbal communication enables one to communicate one's confidence and to appraise that of others. However, in many circumstances, people either cannot explicitly communicate their confidence level (e.g., in an emergency situation) or may be intentionally deceitful (e.g., when playing poker). It is currently unclear whether one can read others' confidence in the absence of verbal communication, and whether one can infer it as accurately as for one's own confidence. To explore these questions, we used an auditory task in which participants either had to guess the confidence of someone else performing the task or to judge their own confidence, in different conditions (i.e., while performing the task themselves or while watching themselves perform the task on a pre-recorded video). Results demonstrate that people can read the confidence someone else has in their decision as accurately as they evaluate their own uncertainty in their decision. Crucially, we show that hetero-metacognition is a Flexible Mechanism that relies on different cues according to the context. Our results support the idea that metacognition leverages the same inference Mechanisms as those involved in theory of mind.
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comparing self and hetero metacognition in the absence of verbal communication
bioRxiv, 2019Co-Authors: Laurene Vuillaume, Jeanremy Martin, Jerome Sackur, Axel CleeremansAbstract:ABSTRACT The ability to infer how confident other people are in their decisions is crucial for regulating social interactions. It is unclear whether one can read others’ confidence in absence of verbal communication and whether one can infer it as accurately as for one’s own confidence. To address these questions, we used an auditory task in which participants had to guess the confidence of someone else performing the task or to judge their own confidence in different conditions (i.e., while performing the task themselves or while watching themselves performing the task on a pre-recorded video). Results show that participants are able to guess the confidence of other people as accurately as when judging their own. Crucially, we show that hetero-metacognition is a Flexible Mechanism relying on different cues according to the context. Our results support the idea that metacognition leverages the same inference Mechanisms as involved in theory of mind.
F M Gambetta - One of the best experts on this subject based on the ideXlab platform.
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engineering nonbinary rydberg interactions via phonons in an optical lattice
Physical Review Letters, 2020Co-Authors: F M Gambetta, F Schmidtkaler, Igor LesanovskyAbstract:Coupling electronic and vibrational degrees of freedom of Rydberg atoms held in optical tweezer arrays offers a Flexible Mechanism for creating and controlling atom-atom interactions. We find that the state-dependent coupling between Rydberg atoms and local oscillator modes gives rise to two- and three-body interactions which are controllable through the strength of the local confinement. This approach even permits the cancellation of two-body terms such that three-body interactions become dominant. We analyze the structure of these interactions on two-dimensional bipartite lattice geometries and explore the impact of three-body interactions on system ground state on a square lattice. Focusing specifically on a system of ^{87}Rb atoms, we show that the effects of the multibody interactions can be maximized via a tailored dressed potential within a trapping frequency range of the order of a few hundred kilohertz and for temperatures corresponding to a >90% occupation of the atomic vibrational ground state. These parameters, as well as the multibody induced timescales, are compatible with state-of-the-art arrays of optical tweezers. Our work shows a highly versatile handle for engineering multibody interactions of quantum many-body systems in most recent manifestations on Rydberg lattice quantum simulators.