Journal articles: 'Local Casimir effect'

1

Herdegen, Andrzej, and Mariusz Stopa. "Global Versus Local Casimir Effect." Annales Henri Poincaré 11, no. 6 (October 21, 2010): 1171–200. http://dx.doi.org/10.1007/s00023-010-0053-4.

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Fermi, Davide, and Livio Pizzocchero. "Local Zeta Regularization and the Casimir Effect." Progress of Theoretical Physics 126, no. 3 (September 2011): 419–34. http://dx.doi.org/10.1143/ptp.126.419.

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Saharian, Aram, and Giampiero Esposito. "Casimir effect with non-local boundary conditions." Journal of Physics A: Mathematical and General 39, no. 18 (April 19, 2006): 5233–47. http://dx.doi.org/10.1088/0305-4470/39/18/032.

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SETARE, M. R., and A. H. REZAEIAN. "TRACE ANOMALY AND CASIMIR EFFECT." Modern Physics Letters A 15, no. 35 (November 20, 2000): 2159–64. http://dx.doi.org/10.1142/s0217732300002449.

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The Casimir energy for scalar field of two parallel conductors in two-dimensional domain wall background, with Dirichlet boundary conditions, is calculated by making use of general properties of renormalized stress–tensor. We show that vacuum expectation values of stress–tensor contain two terms which come from the boundary conditions and the gravitational background. In two dimensions the minimal coupling reduces to the conformal coupling and stress–tensor can be obtained by the local and nonlocal contributions of the anomalous trace. This work shows that there exists a subtle and deep connection between Casimir effect and trace anomaly in curved space–time.

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GIES, H., and A. WEBER. "GEOMETRY-TEMPERATURE INTERPLAY IN THE CASIMIR EFFECT." International Journal of Modern Physics A 25, no. 11 (April 30, 2010): 2279–92. http://dx.doi.org/10.1142/s0217751x10049554.

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We discuss Casimir phenomena which are dominated by long-range fluctuations. A prime example is given by "geothermal" Casimir phenomena where thermal fluctuations in open Casimir geometries can induce significantly enhanced thermal corrections. We illustrate the underlying mechanism with the aid of the inclined-plates configuration, giving rise to enhanced power-law temperature dependences compared to the parallel-plates case. In limiting cases, we find numerical evidence even for fractional power laws induced by long-range fluctuations. We demonstrate that thermal energy densities for open geometries are typically distributed over length scales of 1/T. As an important consequence, approximation methods for thermal corrections based on local energy-density estimates such as the proximity-force approximation are expected to become unreliable even at small surface separations.

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Sorge, Francesco. "Casimir effect around an Ellis wormhole." International Journal of Modern Physics D 29, no. 01 (November 11, 2019): 2050002. http://dx.doi.org/10.1142/s0218271820500029.

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We discuss the Casimir effect in a small cavity, moving in a circular orbit around an Ellis wormhole. We show that the interplay between the spacetime geometry and the cavity orbital motion gives rise to a distortion in the Casimir energy density, causing a reduction of its absolute value. Quite interestingly, such effect can be observed also when the cavity moves on a circular geodesic (albeit unstable) orbit at the wormhole throat, where a comoving observer becomes locally inertial (namely, the observer’s reference frame reduces to a geodesic, Fermi-Walker transported one). In that respect, the discussed effect appears as a nonlocal quantum effect by means of which some properties of the underlying spacetime geometry, hidden to local classical measurements, can be captured and unveiled.

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Petruzziello, Luciano. "Casimir Effect as a Probe for New Physics Phenomenology." Physical Sciences Forum 2, no. 1 (February 22, 2021): 17. http://dx.doi.org/10.3390/ecu2021-09307.

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We show some recent cutting-edge results associated with the Casimir effect. Specifically, we focused our attention on the remarkable sensitivity of the Casimir effect to new physics phenomenology. Such an awareness can be readily discerned by virtue of the existence of extra contributions that the measurable quantities (such as the emergent pressure and strength within the experimental apparatus) acquire for a given physical setting. In particular, by relying on the above framework, we outlined the possibility of detecting the predictions of a novel quantum field theoretical description for particle mixing according to which the flavor and the mass vacuum are unitarily non-equivalent. Furthermore, by extending the very same formalism to curved backgrounds, the opportunity to probe extended models of gravity that encompass local Lorentz symmetry breaking and the strong equivalence principle violation was also discussed. Finally, the influence of quantum gravity on the Casimir effect was briefly tackled by means of heuristic considerations. In a similar scenario, the presence of a minimal length at the Planck scale was the source of the discrepancy with the standard outcomes.

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BLASI, A., R. COLLINA, and J. SASSARINI. "FINITE CASIMIR EFFECT IN QUANTUM FIELD THEORY." International Journal of Modern Physics A 09, no. 10 (April 20, 1994): 1677–702. http://dx.doi.org/10.1142/s0217751x94000728.

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The computation of the Casimir effect is directly linked to the modification of the vacuum energy due to the presence of boundaries. In order to have complete control of the short distance behavior also near the boundary, the analysis is performed in the precise framework of a local, renormalizable quantum field theory which includes the boundary contributions. We show that the presence of soft terms at the boundary, needed to implement Robin's conditions, introduces a free parameter in the final, finite answer, a parameter which has no natural normalization condition within the scheme. We discuss in detail a free massless scalar field in R3 with plane and cylindric boundaries; in particular the second case, where the boundary soft term is essential to remove sub-leading short distance divergencies, suffers the mentioned indeterminacy, which might be removed by a phenomenological interpretation relating the soft term to a microscopic description of the boundary.

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Elizalde, E., and S. D. Odintsov. "Bosonic string with antisymmetric fields and a non-local Casimir effect." Classical and Quantum Gravity 12, no. 12 (December 1, 1995): 2881–86. http://dx.doi.org/10.1088/0264-9381/12/12/006.

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10

MODANESE, GIOVANNI. "LOCAL CONTRIBUTION OF A QUANTUM CONDENSATE TO THE VACUUM ENERGY DENSITY." Modern Physics Letters A 18, no. 10 (March 28, 2003): 683–90. http://dx.doi.org/10.1142/s0217732303009812.

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We evaluate the local contribution gμνL of coherent matter with Lagrangian density L to the vacuum energy density. Focusing on the case of superconductors obeying the Ginzburg–Landau equation, we express the relativistic invariant density L in terms of low-energy quantities containing the pairs density. We discuss under which physical conditions the sign of the local contribution of the collective wave function to the vacuum energy density is positive or negative. Effects of this kind can play an important role in bringing the local changes in the amplitude of gravitational vacuum fluctuations — a phenomenon reminiscent of the Casimir effect in QED.

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11

Saharian, A. A., T. A. Petrosyan, S. V. Abajyan, and B. B. Nersisyan. "Scalar Casimir effect in a linearly expanding universe." International Journal of Geometric Methods in Modern Physics 15, no. 10 (October 2018): 1850177. http://dx.doi.org/10.1142/s0219887818501773.

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We investigate quantum vacuum effects for a massive scalar field, induced by two planar boundaries in background of a linearly expanding spatially flat Friedmann–Robertson–Walker spacetime for an arbitrary number of spatial dimensions. For the Robin boundary conditions and for general curvature coupling parameter, a complete set of mode functions is presented and the related Hadamard function is evaluated. The results are specified for the most important special cases of the adiabatic and conformal vacuum states. The vacuum expectation values of the field squared and of the energy–momentum tensor are investigated for a massive conformally coupled field. The vacuum energy–momentum tensor, in addition to the diagonal components, has nonzero off-diagonal component describing energy flux along the direction perpendicular to the plates. The influence of the gravitational field on the local characteristics of the vacuum state is essential at distances from the boundaries larger than the curvature radius of the background spacetime. In contrast to the Minkowskian bulk, at large distances the boundary-induced expectation values follow as power law for both massless and massive fields. Another difference is that the Casimir forces acting on the separate plates do not coincide if the corresponding Robin coefficients are different. At large separations between the plates the decay of the forces is power law. We show that during the cosmological expansion the forces may change the sign.

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12

Fermi, Davide, and Livio Pizzocchero. "Local Casimir Effect for a Scalar Field in Presence of a Point Impurity." Symmetry 10, no. 2 (January 26, 2018): 38. http://dx.doi.org/10.3390/sym10020038.

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13

Nesterenko, V. V., G. Lambiase, and G. Scarpetta. "Casimir Effect for a Perfectly Conducting Wedge in Terms of Local Zeta Function." Annals of Physics 298, no. 2 (June 2002): 403–20. http://dx.doi.org/10.1006/aphy.2002.6261.

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14

GUERREIRO, A. "On the quantum space–time structure of light." Journal of Plasma Physics 76, no. 6 (August 17, 2010): 833–43. http://dx.doi.org/10.1017/s0022377810000425.

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AbstractWe extend the quantum theory of Time Refraction for a generic spatial and temporal modulation of the optical properties of a medium, such as a dielectric or a gravitational field. The derivation of the local Bogoliubov transformations relating the global electromagnetic modes (valid over the entire span of space and time) with the local modes (valid for the vicinity of each spatial and temporal position) is presented and used in the evaluation of vacuum photon creation by the optical modulations of the medium. We use this approach to relate and review the results of different quantum effects such as the dynamical Casimir effect, space and Time Refraction, the Unruh effect and radiation from superluminal non-accelerated optical boundaries.

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Fermi, Davide, and Livio Pizzocchero. "Local zeta regularization and the scalar Casimir effect IV: The case of a rectangular box." International Journal of Modern Physics A 31, no. 04n05 (February 3, 2016): 1650003. http://dx.doi.org/10.1142/s0217751x16500032.

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Applying the general framework for local zeta regularization proposed in Part I of this series of papers, we compute the renormalized vacuum expectation value of several observables (in particular, of the stress–energy tensor) for a massless scalar field confined within a rectangular box of arbitrary dimension.

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Francescato, Yan, Simon R. Pocock, and Vincenzo Giannini. "On the Non-Local Surface Plasmons’ Contribution to the Casimir Force between Graphene Sheets." Physics 2, no. 1 (January 19, 2020): 22–31. http://dx.doi.org/10.3390/physics2010003.

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Herein we demonstrate the dramatic effect of non-locality on the plasmons which contribute to the Casimir forces, with a graphene sandwich as a case study. The simplicity of this system allowed us to trace each contribution independently, as we observed that interband processes, although dominating the forces at short separations, are poorly accounted for in the framework of the Dirac cone approximation alone, and should be supplemented with other descriptions for energies higher than 2.5 eV. Finally, we proved that distances smaller than 200 nm, despite being extremely relevant to state-of-the-art measurements and nanotechnology applications, are inaccessible with closed-form response function calculations at present.

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Fermi, Davide, and Livio Pizzocchero. "Local zeta regularization and the scalar Casimir effect III. The case with a background harmonic potential." International Journal of Modern Physics A 30, no. 35 (December 20, 2015): 1550213. http://dx.doi.org/10.1142/s0217751x15502139.

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Applying the general framework for local zeta regularization proposed in Part I of this series of papers, we renormalize the vacuum expectation value of the stress-energy tensor (and of the total energy) for a scalar field in presence of an external harmonic potential.

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Tanaka, Satoshi, and Kazuki Kanki. "The Dynamical Casimir Effect in a Dissipative Optomechanical Cavity Interacting with Photonic Crystal." Physics 2, no. 1 (February 7, 2020): 34–48. http://dx.doi.org/10.3390/physics2010005.

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We theoretically study the dynamical Casimir effect (DCE), i.e., parametric amplification of a quantum vacuum, in an optomechanical cavity interacting with a photonic crystal, which is considered to be an ideal system to study the microscopic dissipation effect on the DCE. Starting from a total Hamiltonian including the photonic band system as well as the optomechanical cavity, we have derived an effective Floquet–Liouvillian by applying the Floquet method and Brillouin–Wigner–Feshbach projection method. The microscopic dissipation effect is rigorously taken into account in terms of the energy-dependent self-energy. The obtained effective Floquet–Liouvillian exhibits the two competing instabilities, i.e., parametric and resonance instabilities, which determine the stationary mode as a result of the balance between them in the dissipative DCE. Solving the complex eigenvalue problem of the Floquet–Liouvillian, we have determined the stationary mode with vanishing values of the imaginary parts of the eigenvalues. We find a new non-local multimode DCE represented by a multimode Bogoliubov transformation of the cavity mode and the photon band. We show the practical advantage for the observation of DCE in that we can largely reduce the pump frequency when the cavity system is embedded in a narrow band photonic crystal with a bandgap.

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19

Spirin, Pavel. "Scalar Radiation in Interaction of Cosmic String with Point Charge." Universe 7, no. 7 (June 23, 2021): 206. http://dx.doi.org/10.3390/universe7070206.

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We consider the scalar bremsstrahlung of the spinless relativistic particle, which interacts with infinitely thin cosmic string by linearized gravity. With the iterational scheme, based on the Perturbaion Theory with respect to the Newtonian constant, we compute the radiation amplitude and the emitted energy due to collision. The general phenomenon of mutual cancellation of the leading terms on the local and non-local amplitude, known in the ultrarelativistic regime for several types of collision, also takes place here. Remarkably, this cancellation (destructive interference) is complete, and takes place for any particle’s velocity. We compute the spectral and angular distributions of the emitted waves. Particular attention is paid to the ultrarelativistic case. Due to the radiation emission, a string may lose its energy and decrease the tension; it may affect all field effects, including the vacuum polarization and the Casimir effect, in terms of physical problems with the real cosmic strings.

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Valchev, Galin. "On the effects from the simultaneous occurrence of the critical Casimir and dispersion forces between conical colloid particle and a thick plate immersed in nonpolar critical fluid." MATEC Web of Conferences 145 (2018): 01008. http://dx.doi.org/10.1051/matecconf/201814501008.

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Here we study the interplay between the van der Waals (vdWF) and critical Casimir forces (CCF), as well as the total force (TF) between a conical colloid particle and a thick planar slab. We do that using general scaling arguments and mean-field type calculations utilizing the so-called “surface integration approach”, a generalization of the well known Derjaguin approximation. Its usage in the present research, requires knowledge on the forces between two parallel slabs, confining in between some fluctuating fluid medium characterized by its temperature T and chemical potential μ. The surfaces of the colloid particle and the slab are assumed coated by thin layers exerting strong preference to the liquid phase of a simple fluid, or one of the components of a binary mixture, modeled by strong adsorbing local surface potentials, ensuring the so-called (+,+) boundary conditions. On the other hand, the core region of the slab and the particle, influence the fluid by long-ranged competing dispersion potentials. We demonstrate that for a suitable set of colloid-fluid, slab-fluid, and fluid-fluid coupling parameters the competition between the effects due to the coatings and the core regions of the objects, result, when one changes T or μ, in sign change of the Casimir force (CF) and the TF acting between the colloid and the slab. Such an effect can provide a strategy for solving problems with handling, feeding, trapping and fixing of microparts in nanotechnology.

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MOTTOLA, EMIL. "THE TRACE ANOMALY AND DYNAMICAL VACUUM ENERGY IN COSMOLOGY." International Journal of Modern Physics A 25, no. 11 (April 30, 2010): 2391–408. http://dx.doi.org/10.1142/s0217751x10049670.

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The trace anomaly of conformal matter implies the existence of massless scalar poles in physical amplitudes involving the stress-energy tensor. These poles may be described by a local effective action with massless scalar fields, which couple to classical sources, contribute to gravitational scattering processes, and can have long range gravitational effects at macroscopic scales. In an effective field theory approach, the effective action of the anomaly is an infrared relevant term that should be added to the Einstein-Hilbert action of classical General Relativity to take account of macroscopic quantum effects. The additional scalar degrees of freedom contained in this effective action may be understood as responsible for both the Casimir effect in flat spacetime and large quantum backreaction effects at the horizon scale of cosmological spacetimes. These effects of the trace anomaly imply that the cosmological vacuum energy is dynamical, and its value depends on macroscopic boundary conditions at the cosmological horizon scale, rather than sensitivity to the extreme ultraviolet Planck scale.

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Kauffman, Stuart A. "Quantum Gravity If Non-Locality Is Fundamental." Entropy 24, no. 4 (April 15, 2022): 554. http://dx.doi.org/10.3390/e24040554.

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I take non-locality to be the Michelson–Morley experiment of the early 21st century, assume its universal validity, and try to derive its consequences. Spacetime, with its locality, cannot be fundamental, but must somehow be emergent from entangled coherent quantum variables and their behaviors. There are, then, two immediate consequences: (i). if we start with non-locality, we need not explain non-locality. We must instead explain an emergence of locality and spacetime. (ii). There can be no emergence of spacetime without matter. These propositions flatly contradict General Relativity, which is foundationally local, can be formulated without matter, and in which there is no “emergence” of spacetime. If these be true, then quantum gravity cannot be a minor alteration of General Relativity but must demand its deep reformulation. This will almost inevitably lead to: matter not only curves spacetime, but “creates” spacetime. We will see independent grounds for the assertion that matter both curves and creates spacetime that may invite a new union of quantum gravity and General Relativity. This quantum creation of spacetime consists of: (i) fully non-local entangled coherent quantum variables. (ii) The onset of locality via decoherence. (iii) A metric in Hilbert space among entangled quantum variables by the sub-additive von Neumann entropy between pairs of variables. (iv) Mapping from metric distances in Hilbert space to metric distances in classical spacetime by episodic actualization events. (v) Discrete spacetime is the relations among these discrete actualization events. (vi) “Now” is the shared moment of actualization of one among the entangled variables when the amplitudes of the remaining entangled variables change instantaneously. (vii) The discrete, successive, episodic, irreversible actualization events constitute a quantum arrow of time. (viii) The arrow of time history of these events is recorded in the very structure of the spacetime constructed. (ix) Actual Time is a succession of two or more actual events. The theory inevitably yields a UV cutoff of a new type. The cutoff is a phase transition between continuous spacetime before the transition and discontinuous spacetime beyond the phase transition. This quantum creation of spacetime modifies General Relativity and may account for Dark Energy, Dark Matter, and the possible elimination of the singularities of General Relativity. Relations to Causal Set Theory, faithful Lorentzian manifolds, and past and future light cones joined at “Actual Now” are discussed. Possible observational and experimental tests based on: (i). the existence of Sub- Planckian photons, (ii). knee and ankle discontinuities in the high-energy gamma ray spectrum, and (iii). possible experiments to detect a creation of spacetime in the Casimir system are discussed. A quantum actualization enhancement of repulsive Casimir effect would be anti-gravitational and of possible practical use. The ideas and concepts discussed here are not yet a theory, but at most the start of a framework that may be useful.

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23

Scardicchio, A., and R. L. Jaffe. "Casimir effects: An optical approach II. Local observables and thermal corrections." Nuclear Physics B 743, no. 3 (May 2006): 249–75. http://dx.doi.org/10.1016/j.nuclphysb.2006.02.038.

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DEHGHAN, Z., and S. S. GOUSHEH. "CASIMIR ENERGY, FERMION FRACTIONALIZATION AND STABILITY OF A FERMI FIELD IN AN ELECTRIC POTENTIAL IN (1+1) DIMENSIONS." International Journal of Modern Physics A 27, no. 18 (July 17, 2012): 1250093. http://dx.doi.org/10.1142/s0217751x12500935.

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In this paper we compute and study the Casimir energy, vacuum polarization and the resulting fermion fractionalization, the phase shifts and the stability of the bound states of a Dirac field, all due to its interaction with an electric potential in (1+1) dimension. We also explore the inter-relation between these effects. All of these effects are different manifestations of one single source, which is the distortion of the fermionic spectrum and appears as spectral deficiencies in the continua and bound states. We compute and display the spatial densities of these deficiencies and those of the bound states, along with their associated energy densities. We find that in both cases the total spatial densities of states with E > 0 and E < 0 are exact mirror images of each other. Therefore these densities for the complete spectrum are unchanged as compared to the free case, and in particular they remain uniform. The densities of states with E < 0 are precisely the vacuum polarization density and the Casimir energy density, respectively. We find that the vacuum polarization is in general noninteger. We then compute and display the energy densities of the spectral deficiencies in the momentum space, and show that levels exiting or entering the continua leave their distinctive marks on these energy densities. We also use the phase shifts to calculate the Casimir energy and obtain the same result as in the direct calculation. In this problem the Casimir energy is always positive and is on the average an increasing function of the depth and width of the potential. It has a cusp whenever an energy level crosses E = 0. These cusps are local maxima in the extreme relativistic limits. Finally we show that the taking the Casimir energy into account, the total energy will be stable under small fluctuations in the parameters of the potential. However only the first two bound states are absolutely stable in the sense that their total energy is smaller than the mass.

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Attia, Mohamed A., and Salwa A. Mohamed. "Pull-In Instability of Functionally Graded Cantilever Nanoactuators Incorporating Effects of Microstructure, Surface Energy and Intermolecular Forces." International Journal of Applied Mechanics 10, no. 08 (September 2018): 1850091. http://dx.doi.org/10.1142/s1758825118500916.

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In this paper, an integrated non-classical continuum model is developed to investigate the pull-in instability of electrostatically actuated functionally graded nanocantilevers. The model accounts for the simultaneous effects of local-microstructure, surface elasticity and surface residual in the presence of fringing field as well as Casimir and van der Waals forces. The modified couple stress and Gurtin–Murdoch surface elasticity theories are employed to conduct the scaling effects of microstructure and surface energy, respectively, in the context of Euler–Bernoulli beam hypothesis. Bulk and surface material properties are varied according to the power-law distribution through the beam thickness. The physical neutral axis position for mentioned FG nanobeams is considered. Hamilton principle is employed to derive the nonlinear size-dependent governing equations and the non-classical boundary conditions. The resulting nonlinear differential equations are solved utilizing the generalized differential quadrature method (GDQM). In addition, the non-classical boundary conditions of nanocantilever beams due to surface residual stress are exactly implemented. After validation of the obtained results by previously available data in the literature, the influences of different geometrical and material parameters on the pull-in instability of the FG nanocantilevers are examined in detail. It is concluded that the pull-in behavior of electrically actuated FG micro/nanocantilevers is significantly influenced by the material distribution, material length scale parameter, surface elasticity constant, surface residual stress, initial gap, slenderness ratio, Casimir, and van der Waals forces. The obtained results can be considered for modeling and analysis of electrically actuated FG nanocantilevers.

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Dedkov, G. V. "Nonequilibrium Casimir–Lifshitz friction force and anomalous radiation heating of a small particle." Applied Physics Letters 121, no. 23 (December 5, 2022): 231603. http://dx.doi.org/10.1063/5.0115748.

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This paper presents the results of calculating the Casimir–Lifshitz friction force and the heating rate of a small metal particle moving above a metal surface (thick plate) in the case of their different local temperatures. The case of normal nonmagnetic metals (Au) is considered. There is a strong interplay of temperatures, particle velocity, and separation distance, which leads to an anomalous direction of the heat flow between bodies and a peak temperature dependence of the friction force at sufficiently low temperatures of the order of 1–10 K. In particular, a “hot” moving particle can additionally receive heat from a “cold” surface. The conditions for experimental measurement of these effects are discussed.

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Saharian, Aram A. "Quantum Vacuum Effects in Braneworlds on AdS Bulk." Universe 6, no. 10 (October 15, 2020): 181. http://dx.doi.org/10.3390/universe6100181.

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We review the results of investigations for brane-induced effects on the local properties of quantum vacuum in background of AdS spacetime. Two geometries are considered: a brane parallel to the AdS boundary and a brane intersecting the AdS boundary. For both cases, the contribution in the vacuum expectation value (VEV) of the energy–momentum tensor is separated explicitly and its behavior in various asymptotic regions of the parameters is studied. It is shown that the influence of the gravitational field on the local properties of the quantum vacuum is essential at distance from the brane larger than the AdS curvature radius. In the geometry with a brane parallel to the AdS boundary, the VEV of the energy–momentum tensor is considered for scalar field with the Robin boundary condition, for Dirac field with the bag boundary condition and for the electromagnetic field. In the latter case, two types of boundary conditions are discussed. The first one is a generalization of the perfect conductor boundary condition and the second one corresponds to the confining boundary condition used in QCD for gluons. For the geometry of a brane intersecting the AdS boundary, the case of a scalar field is considered. The corresponding energy–momentum tensor, apart from the diagonal components, has nonzero off-diagonal component. As a consequence of the latter, in addition to the normal component, the Casimir force acquires a component parallel to the brane.

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Nazari, Borzoo. "Quasi-local stress-tensor formalism and the Casimir effect." Modern Physics Letters A, October 7, 2022. http://dx.doi.org/10.1142/s0217732322501607.

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We apply the quasi-local stress–energy tensor formalism to the Casimir effect of a scalar field confined between conducting planes located in a static spacetime. We show that the surface energy vanishes for both Neumann and Dirichlet boundary conditions and consequently the volume Casimir energy reduces to the famous zero point energy of the quantum field, i.e. [Formula: see text]. This enables us to reinforce previous results in the literature and extend the calculations to the case of massive and arbitrarily coupled scalar field. We found that there exists a first-order perturbation correction to the Casimir energy contrary to previous claims which state that it vanishes. This shows many orders of magnitude greater than previous estimations for the energy corrections and makes it detectable by near future experiments.

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Juárez Aubry, Benito Alberto, and Ricardo Weder. "A short review of the Casimir effect with emphasis on dynamical boundary conditions." Suplemento de la Revista Mexicana de Física 3, no. 2 (April 5, 2022). http://dx.doi.org/10.31349/suplrevmexfis.3.020714.

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We give a short review on the static and dynamical Casimir effects, recalling their historical prediction, as well as their more recent experimental verifications. We emphasise on the central role played by so-called dynamical boundary conditions (for which the boundary condition depends on a second time derivative of the field) in the experimental verification of the dynamical Casimir effect by Wilson et al. We then go on to review our previous work on the static Casimir effect with dynamical boundary conditions, providing an overview on how to compute the so-called local Casimir energy, the total Casimir energy and the Casimir force. We give as a future perspective the direction in which this work should be generalised to put the theoretical predictions of the dynamical Casimir effect experiments on a rigorous footing.

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Escobar, C. A., Leonardo Medel, and A. Martín-Ruiz. "Casimir effect in Lorentz-violating scalar field theory: A local approach." Physical Review D 101, no. 9 (May 11, 2020). http://dx.doi.org/10.1103/physrevd.101.095011.

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31

Fischetti, Sebastian, Lucas Wallis, and Toby Wiseman. "Does the round sphere maximize the free energy of (2+1)-dimensional QFTs?" Journal of High Energy Physics 2020, no. 10 (October 2020). http://dx.doi.org/10.1007/jhep10(2020)078.

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Abstract We examine the renormalized free energy of the free Dirac fermion and the free scalar on a (2+1)-dimensional geometry ℝ × Σ, with Σ having spherical topology and prescribed area. Using heat kernel methods, we perturbatively compute this energy when Σ is a small deformation of the round sphere, finding that at any temperature the round sphere is a local maximum. At low temperature the free energy difference is due to the Casimir effect. We then numerically compute this free energy for a class of large axisymmetric deformations, providing evidence that the round sphere globally maximizes it, and we show that the free energy difference relative to the round sphere is unbounded below as the geometry on Σ becomes singular. Both our perturbative and numerical results in fact stem from the stronger finding that the difference between the heat kernels of the round sphere and a deformed sphere always appears to have definite sign. We investigate the relevance of our results to physical systems like monolayer graphene consisting of a membrane supporting relativistic QFT degrees of freedom.

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Persinger, Michael A. "Translocations In Space-Time and Simultaneous States of the Universe: Convergent Quantifications and Alternative Solutions from the Principles of Physics for the Challenges of â€œTime Travelâ€ and â€œParallel Universesâ€." JOURNAL OF ADVANCES IN PHYSICS, July 30, 2016, 4058–69. http://dx.doi.org/10.24297/jap.v11i8.195.

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Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Translation of four dimensional axes anywhere within the spatial and temporal boundaries of the universe would require quantitative values from convergence between parameters that reflect these limits. The presence of entanglement and volumetric velocities indicates that the initiating energy for displacement and transposition of axes would be within the upper limit of the rest mass of a single photon which is the same order of magnitude as a macroscopic Hamiltonian of the modified SchrÃ¶dinger wave function. The representative metaphor is that any local 4-D geometry, rather than displaying restricted movement through Minkowskian space, would instead expand to the total universal space-time volume before re-converging into another location where it would be subject to cause-effect. Within this transient context the contributions from the anisotropic features of entropy and the laws of thermodynamics would be minimal.Â The central operation of a fundamental unit of 10-20 J, the hydrogen line frequency, and the Bohr orbital time for ground state electrons would be required for the relocalized manifestation. Similar quantified convergence occurs for the ~1012 parallel states within space per Planckâ€™s time which solve for phase-shift increments where Casimir and magnetic forces intersect. Â Experimental support for these interpretations and potential applications is considered. The multiple, convergent solutions of basic universal quantities suggest that translations of spatial axes into adjacent spatial states and the transposition of four dimensional configurations any where and any time within the universe may be accessed but would require alternative perspectives and technologies.

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Journal articles on the topic 'Local Casimir effect'

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