The Experts below are selected from a list of 294 Experts worldwide ranked by ideXlab platform
Mauro Antezza - One of the best experts on this subject based on the ideXlab platform.
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Steady entanglement out of Thermal Equilibrium
EPL - Europhysics Letters, 2013Co-Authors: Bruno Bellomo, Mauro AntezzaAbstract:We study two two-level atomic quantum systems (qubits) placed close to a body held at a temperature different from that of the surrounding walls. While at Thermal Equilibrium the two-qubit dynamics is characterized by non-entangled steady Thermal states, we show that the absence of Thermal Equilibrium may bring to the generation of entangled steady states. Remarkably, this entanglement emerges from the two-qubit dissipative dynamic itself, without any further external action on the two qubits, suggesting a new protocol to create and protect entanglement which is intrinsically robust to environmental effects.
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Steady entanglement out of Thermal Equilibrium
EPL (Europhysics Letters), 2013Co-Authors: Bruno Bellomo, Mauro AntezzaAbstract:We study two two-level atomic quantum systems (qubits) placed close to a body held at a temperature different from that of the surrounding walls. While at Thermal Equilibrium the two-qubit dynamics is characterized by not entangled steady Thermal states, we show that absence of Thermal Equilibrium may bring to the generation of entangled steady states. Remarkably, this entanglement emerges from the two-qubit dissipative dynamic itself, without any further external action on the two qubits, suggesting a new protocol to produce and protect entanglement which is intrinsically robust to environmental effects.
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Casimir-Lifshitz Force Out of Thermal Equilibrium and Asymptotic Nonadditivity
Physical review letters, 2006Co-Authors: Mauro Antezza, Lev P. Pitaevskii, Sandro Stringari, Vitaly B. SvetovoyAbstract:We investigate the force acting between two parallel plates held at different temperatures. The force reproduces, as limiting cases, the well-known Casimir-Lifshitz surface-surface force at Thermal Equilibrium and the surface-atom force out of Thermal Equilibrium recently derived by M. Antezza et al., Phys. Rev. Lett. 95, 113202 (2005). The asymptotic behavior of the force at large distances is explicitly discussed. In particular when one of the two bodies is a rarefied gas the force is not additive, being proportional to the square root of the density. Nontrivial crossover regions at large distances are also identified.
Bassam Abu-hijleh - One of the best experts on this subject based on the ideXlab platform.
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Thermal Equilibrium in Transient Forced Convection Porous Channel Flow
Transport in Porous Media, 2004Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in the transient forced convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio αR, the volumetric Nusselt number Nu, the dimensionless channel length ξmax, Peclet number Pe, and the solid to fluid total Thermal capacity ratio CR. The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.
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Thermal Equilibrium IN TRANSIENT CONJUGATED FORCED-CONVECTION CHANNEL FLOW
Numerical Heat Transfer Part A-applications, 2003Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in transient conjugated forced-convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio f R , the Biot number Bi, the dimensionless channel length \xi_{\max} , the Peclet number Pe, and the solid-to-fluid total Thermal capacity ratio C R . The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.
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Validation of Thermal Equilibrium Assumption in Transient Forced Convection Flow in Porous Channel
Transport in Porous Media, 2002Co-Authors: Moh’d A. Al-nimr, Bassam Abu-hijlehAbstract:The validity of the local Thermal Equilibrium assumption in the transient forced convection channel flow is investigated analytically. Closed form expressions are presented for the temperatures of the fluid and solid domains and for the criterion which insures the validity of the local Thermal Equilibrium assumption. It is found that four dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the porosity ∈, the volumetric Biot number Bi, the dimensionless channel length ξ_max and the solid to fluid total Thermal capacity ratio C _R. The qualitative and quantitative aspects of the effects of these four parameters on the channel Thermal Equilibrium relaxation time are investigated.
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Validation of the Thermal Equilibrium assumption in the transient conjugated forced convection channel flow
Heat and Mass Transfer, 2001Co-Authors: Moh’d A. Al-nimr, Bassam Abu-hijlehAbstract:The validity of the local Thermal Equilibrium assumption in the transient conjugated forced convection channel flow is investigated analytically. Closed form expressions are presented for the temperatures of the fluid and solid domains and for the criterion which insure the validity of the local Thermal Equilibrium assumption. It is found that three dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Biot number Bi, the dimensionless channel length ξmax and the solid to fluid total Thermal capacity ratio C R. The qualitative and quantitative aspects of the effects of these three parameters on the channel Thermalization time are investigated.
Moh’d A. Al-nimr - One of the best experts on this subject based on the ideXlab platform.
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Validation of the Thermal Equilibrium Assumption in Periodic Natural Convection in Porous Domains
International Journal of Thermophysics, 2005Co-Authors: A. F. Khadrawi, Montasser S. Tahat, Moh’d A. Al-nimrAbstract:The validity of the local Thermal Equilibrium assumption in the periodic free convection channel flow is investigated analytically. Two cases are considered where in the first case transverse conduction in the solid domain is included while in the second case transverse conduction in the fluid domain is included. The periodic disturbance in the free convection flow is due to a periodic Thermal disturbance imposed on the channel walls. The Darcy–Brinkman model is used to model the flow inside the porous domain. It is found that four dimensionless parameters control the local Thermal Equilibrium assumption in the first case and five parameters control the local Equilibrium assumption in the second case. The criteria that secure the validity of the local Thermal Equilibrium assumption are derived.
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Thermal Equilibrium in Transient Forced Convection Porous Channel Flow
Transport in Porous Media, 2004Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in the transient forced convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio αR, the volumetric Nusselt number Nu, the dimensionless channel length ξmax, Peclet number Pe, and the solid to fluid total Thermal capacity ratio CR. The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.
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Examination of the Thermal Equilibrium Assumption in Transient Natural Convection Flow in Porous Channel
Transport in Porous Media, 2003Co-Authors: A. F. Khadrawi, Moh’d A. Al-nimrAbstract:The local Thermal Equilibrium assumption in the transient natural convection channel flow is investigated numerically. The Darcy–Brinkman–Forchheimer model is used to model the flow inside the porous domain. The effect of different parameters on the validity of the local Thermal Equilibrium assumption is examined. It is found that the volumetric Nusselt number has the most significant effect on the local Thermal Equilibrium assumption.
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Thermal Equilibrium IN TRANSIENT CONJUGATED FORCED-CONVECTION CHANNEL FLOW
Numerical Heat Transfer Part A-applications, 2003Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in transient conjugated forced-convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio f R , the Biot number Bi, the dimensionless channel length \xi_{\max} , the Peclet number Pe, and the solid-to-fluid total Thermal capacity ratio C R . The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.
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Validation of Thermal Equilibrium Assumption in Transient Forced Convection Flow in Porous Channel
Transport in Porous Media, 2002Co-Authors: Moh’d A. Al-nimr, Bassam Abu-hijlehAbstract:The validity of the local Thermal Equilibrium assumption in the transient forced convection channel flow is investigated analytically. Closed form expressions are presented for the temperatures of the fluid and solid domains and for the criterion which insures the validity of the local Thermal Equilibrium assumption. It is found that four dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the porosity ∈, the volumetric Biot number Bi, the dimensionless channel length ξ_max and the solid to fluid total Thermal capacity ratio C _R. The qualitative and quantitative aspects of the effects of these four parameters on the channel Thermal Equilibrium relaxation time are investigated.
Jeremy J. Goodman - One of the best experts on this subject based on the ideXlab platform.
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Ruling out bosonic repulsive dark matter in Thermal Equilibrium
Monthly Notices of the Royal Astronomical Society, 2012Co-Authors: Zachary Slepian, Jeremy J. GoodmanAbstract:Self-interacting dark matter, especially bosonic, has been considered a promising candidate to replace cold dark matter (CDM) as it resolves some of the problems associated with CDM. Here, we rule out the possibility that dark matter is a repulsive boson in Thermal Equilibrium. We develop the model first proposed by Goodman in 2000 and derive the equation of state at finite temperature. IsoThermal spherical halo models indicate a Bose–Einstein condensed core surrounded by a non-degenerate envelope, with an abrupt density drop marking the boundary between the two phases. Comparing this feature with observed rotation curves constrains the interaction strength of our model's dark matter particle, and Bullet Cluster measurements constrain the scattering cross-section. Both ultimately can be cast as constraints on the particle's mass. We find these two constraints cannot be satisfied simultaneously in any realistic halo model – and hence dark matter cannot be a repulsive boson in Thermal Equilibrium. It is still left open that dark matter may be a repulsive boson provided it is not in Thermal Equilibrium; this requires that the mass of the particle be significantly less than a millivolt.
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ruling out bosonic repulsive dark matter in Thermal Equilibrium
arXiv: Cosmology and Nongalactic Astrophysics, 2011Co-Authors: Zachary Slepian, Jeremy J. GoodmanAbstract:Self-interacting dark matter (SIDM), especially bosonic, has been considered a promising candidate to replace cold dark matter (CDM) as it resolves some of the problems associated with CDM. Here, we rule out the possibility that dark matter is a repulsive boson in Thermal Equilibrium. We develop the model first proposed by Goodman (2000) and derive the equation of state at finite temperature. IsoThermal spherical halo models indicate a Bose-Einstein condensed core surrounded by a non-degenerate envelope, with an abrupt density drop marking the boundary between the two phases. Comparing this feature with observed rotation curves constrains the interaction strength of our model's DM particle, and Bullet Cluster measurements constrain the scattering cross section. Both ultimately can be cast as constraints on the particle's mass. We find these two constraints cannot be satisfied simultaneously in any realistic halo model---and hence dark matter cannot be a repulsive boson in Thermal Equilibrium. It is still left open that DM may be a repulsive boson provided it is not in Thermal Equilibrium; this requires that the mass of the particle be significantly less than a millivolt.
Maria A. Häder - One of the best experts on this subject based on the ideXlab platform.
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Thermal Equilibrium in Transient Forced Convection Porous Channel Flow
Transport in Porous Media, 2004Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in the transient forced convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio αR, the volumetric Nusselt number Nu, the dimensionless channel length ξmax, Peclet number Pe, and the solid to fluid total Thermal capacity ratio CR. The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.
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Thermal Equilibrium IN TRANSIENT CONJUGATED FORCED-CONVECTION CHANNEL FLOW
Numerical Heat Transfer Part A-applications, 2003Co-Authors: Bassam Abu-hijleh, Moh’d A. Al-nimr, Maria A. HäderAbstract:The validity of the local Thermal Equilibrium assumption in transient conjugated forced-convection channel flow is investigated numerically. Axial conduction in both fluid and solid domains is included. It is found that five dimensionless parameters control the local Thermal Equilibrium assumption. These parameters are the Thermal diffusivity ratio f R , the Biot number Bi, the dimensionless channel length \xi_{\max} , the Peclet number Pe, and the solid-to-fluid total Thermal capacity ratio C R . The qualitative and quantitative aspects of the effects of these five parameters on the channel Thermalization time are investigated.