Casimir Effect Research Papers - Academia.edu (original) (raw)

Traditional studies of human consciousness assume the necessitation of dynamic, time-varying metabolic processes often without consideration of the properties of and interactions with the spatial environment within which these processes... more

Traditional studies of human consciousness assume the necessitation of dynamic, time-varying metabolic processes often without consideration of the properties of and interactions with the spatial environment within which these processes occur. Quantitative electroencephalographic (QEEG) measurements were obtained from an adult human brain specimen, preserved in ethanol-formalin-acetic acid (EFA). Probes were inserted into gyri approximating areas which underlie QEEG channels corresponding to the 10-20 International System of Electrode Placement and referenced to a living human ear. Before measurements were obtained, the specimen was submerged for 20 min in EFA (pH<3) or distilled H2O (pH > 5). During measurements, the brain was either placed on a flat surface, within a polystyrene box, or within a polyethylene human replica skull. Baseline measures were obtained with applied filters so as to eliminate ambient electromagnetic noise. Independent Component Analysis (ICA) performed upon the QEEG data revealed two major activation patterns. The first activation pattern consisted of a right temporo-occipital profile, which dominated all conditions. However, a second pattern emerged: bilateral frontal lobe and left supramarginal gyrus activation. This second pattern was only observed when the experimental conditions approximated those that would be expected to closely simulate the human body (i.e. brain pH approached neutrality and was contained within a skull). In order to identify a potential mechanism, environmental electrodynamics were considered. Raw data from all conditions as well as data collected from an induction coil which measures Schumann oscillations from the Earth’s geomagnetic field were extracted and spectral analyzed. Correlational analyses of spectral densities within the frequency band corresponding to the fundamental mode of the Schumann field (7Hz – 9Hz) revealed significant relationships that were present only when the brain was contained within a skull (r = -.25, p<.01) or approached pH neutrality (r = -.29, p< .001). These results are indicative of a
relationship between the Earth’s magnetic field, the human skull, water, and areas of the brain associated with the construction of the sense of self.

Over the last decade, there has been a respectable level of scientific interest regarding the concept of a warp drive. This is a hypothetical propulsion device that could theoretically circumvent the traditional limitations of special... more

Over the last decade, there has been a respectable level of scientific interest regarding the concept of a warp drive. This is a hypothetical propulsion device that could theoretically circumvent the traditional limitations of special relativity which restricts spacecraft to sub-light velocities. Any breakthrough in this field would revolutionize space exploration and open the doorway to interstellar travel. This article discusses a novel approach to generating the warp bubble necessary for such propulsion; the mathematical details of this theory are discussed in an article published in the Journal of the British Interpanetary Society. The theory is based on some of the exciting predictions coming out of string theory and it is the aim of this article to introduce the warp drive idea from a non-mathematical perspective that should be accessible to a wide range of readers.

– Quantum fluctuations of the electromagnetic field in the medium surrounding two discharged macroscopic polarizable bodies induce a force between the two bodies, the so called Casimir force. In the last two decades many experiments have... more

– Quantum fluctuations of the electromagnetic field in the medium surrounding two discharged macroscopic polarizable bodies induce a force between the two bodies, the so called Casimir force. In the last two decades many experiments have accurately measured this force, and significant efforts are made to harness it in the actuation of micro and nano machines. The inherent many body character of the Casimir force makes its computation very difficult in non-planar geometries, like the standard experimental sphere-plate configuration. Here we derive an approximate semi-analytic formula for the sphere-plate Casimir force, which is both easy to compute numerically and very accurate at all distances. By a comparison with the fully converged exact scattering formula, we show that the error made by the approximate formula is indeed much smaller than the uncertainty of present and foreseeable Casimir experiments.

An analysis of the physical implications of abstractness reveals the reality of three interconnected modes of existence: abstract, virtual and concrete. This triple-aspect monism clarifies the ontological status of subatomic quantum... more

An analysis of the physical implications of abstractness reveals the reality of three interconnected modes of existence: abstract, virtual and concrete. This triple-aspect monism clarifies the ontological status of subatomic quantum particles. It also provides a non-spooky solution to the weirdness of quantum physics and a new outlook for the mind-body problem. The ontological implications are profound for both physics and philosophy.

In this work a generalization of the Bogoliubov transformation is developed to describe a space compactified fermionic field. The method is the fermion counterpart of the formalism introduced earlier for bosons (J. C. da Silva, A. Matos... more

In this work a generalization of the Bogoliubov transformation is developed to describe a space compactified fermionic field. The method is the fermion counterpart of the formalism introduced earlier for bosons (J. C. da Silva, A. Matos Neto, F.C. Khanna and A.E. Santana, Phys. Rev. A 66 (2002) 052101), and is based on the thermofield dynamics approach. We analyze the energy-momentum tensor for the Casimir effect of a free massless fermion system in a N-dimensional box in contact with a heat bath. As a particular situation we calculate the Casimir energy and pressure for the field in a 3-dimensional box. One interesting result is that the attractive or repulsive nature of the Casimir pressure can change depending on the rate among the sizes. This fact is analyzed with specific examples.

PREFACE Gravitation (the attractive force existing between any two objects present in the universe that have mass) refers to one of the four fundamental forces in physics that are responsible for the attraction between masses. The other... more

PREFACE Gravitation (the attractive force existing between any two objects present in the universe that have mass) refers to one of the four fundamental forces in physics that are responsible for the attraction between masses. The other three fundamental forces are strong nuclear power, weak nuclear power and electromagnetism. In comparison to these other three forces, gravitation is certainly the "odd" one. While there is one single theory called the "Grand Unified Theory" that describes the other three forces, gravitation is explained solely by Einstein's general theory of relativity. According to that general theory of relativity, masses cause a distortion of the space-time structure around them. Any other mass that comes closer will experience the warping of space-time, and this appears to us as an attractive force between two masses. We will reason that this view is the wrong side of the coin. By turning over that same coin, another possibility appears that has a much stronger argument and brings out the true nature of gravitation. In that search, a number of fixed assumptions were reviewed and there, too, surprising new insights emerged. The phenomenon of the "spin" of elementary particles finally gets a plausible explanation, the reason for the expansion of the universe and the consequences involved showing a different reality, and the key in the lock of the Grand Unification theory has been turned, opening up a new dimension in physics. Let us take a first step : " … Einstein himself believed that the theory of general relativity could not properly function without a medium … " so the big question is where to look for that nebulous concept and determine what its energetic signature is?

The problem of estimating the thermal corrections to the Casimir and Casimir-Polder interactions in systems involving conducting plates has attracted considerable attention in the recent literature on dispersion forces. Alternative... more

The problem of estimating the thermal corrections to the Casimir and Casimir-Polder interactions in systems
involving conducting plates has attracted considerable attention in the recent literature on dispersion forces.
Alternative theoretical models, based on distinct low-frequency extrapolations of the plate’s reflection coefficient
for transverse electric TE modes, provide widely different predictions for the magnitude of this correction.
In this paper we examine the most widely used prescriptions for this reflection coefficient from the point
of view of their consistency with the Bohr–van Leeuwen theorem of classical statistical physics, stating that at
thermal equilibrium transverse electromagnetic fields decouple from matter in the classical limit. We find that
the theorem is satisfied if and only if the TE reflection coefficient vanishes at zero frequency in the classical
limit. This criterion appears to rule out some of the models that have been considered recently for describing
the thermal correction to the Casimir pressure with nonmagnetic metallic plates.

Within the frame of macroscopic QED in linear, causal media, we study the radiation force of Casimir-Polder type acting on an atom which is positioned near dispersing and absorbing magnetodielectric bodies and initially prepared in an... more

Within the frame of macroscopic QED in linear, causal media, we study the radiation force of Casimir-Polder type acting on an atom which is positioned near dispersing and absorbing magnetodielectric bodies and initially prepared in an arbitrary electronic state. It is shown that minimal and multipolar coupling lead to essentially the same lowest-order perturbative result for the force acting on an atom in an energy eigenstate. To go beyond perturbation theory, the calculations are based on the exact center-of-mass equation of motion. For a nondriven atom in the weak-coupling regime, the force as a function of time is a superposition of force components that are related to the electronic density-matrix elements at a chosen time. Even the force component associated with the ground state is not derivable from a potential in the ususal way, because of the position dependence of the atomic polarizability. Further, when the atom is initially prepared in a coherent superposition of energy eigenstates, then temporally oscillating force components are observed, which are due to the interaction of the atom with both electric and magnetic fields.

Using von Neumann’s continuous geometry in conjunction with A. Connes’ noncommutative geometry an exact mathematical-topological picture of quantum spacetime is developed ab initio. The final result coincides with the general conclusion... more

Using von Neumann’s continuous geometry in conjunction with A. Connes’ noncommutative geometry an exact mathematical-topological picture of quantum spacetime is developed ab initio. The final result coincides with the general conclusion of E-infinity theory and previous results obtained in the realm of high energy physics. In particular it is concluded that the quantum particle and the quantum wave spans quantum spacetime and conversely quantum particles and waves mutates from quantum spacetime.

The purpose of this paper is to investigate the possibility that the Casimir effect, normally very weak, is strong enough to be significant on the scale of nuclear forces around 1 femtometer (fm = 10-15m). Computations were performed for... more

The purpose of this paper is to investigate the possibility that the Casimir effect, normally very weak, is strong enough to be significant on the scale of nuclear forces around 1 femtometer (fm = 10-15m). Computations were performed for the Casimir effect between two spheres using a proximity force approximation. It was found that at 2.6 fm the computed Casimir force is strong enough to overcome Coulomb repulsion and at 0.8 fm it is 20 times stronger than Coulomb repulsion. These values indicate that this strong Casimir force is important on scales of distance consistent with the nuclear force. With refinement it appears likely that the strong Casimir force can account for the nuclear force in its entirety allowing unification of the nuclear force with quantum electrodynamic theory.

The derivation of Casimir forces between dielectrics can be simplified by ignoring absorption, calculating energy changes due to displacements of the dielectrics, and only then admitting absorption by allowing permittivities to be... more

The derivation of Casimir forces between dielectrics can be simplified by ignoring absorption, calculating energy changes due to displacements of the dielectrics, and only then admitting absorption by allowing permittivities to be complex. As a first step towards a better understanding of this situation we consider in this paper the model of a dielectric as a collection of oscillators, each of which is coupled to a reservoir giving rise to damping and Langevin forces on the oscillators and a noise polarization acting as a source of a fluctuating electromagnetic (EM) field in the dielectric. The model leads naturally to expressions for the quantized EM fields that are consistent with those obtained by different approaches, and also results in a fluctuation-dissipation relation between the noise polarization and the imaginary part of the permittivity. Our main result is the derivation of an expression for the QED energy density of a uniform dispersive, absorbing media in thermal equil...

Analog models can be used to investigate aspects of a target system we might not have easy empirical access to. Evidence from an analog model has, under certain strict conditions, been used to argue for the confirmation of a target theory... more

Analog models can be used to investigate aspects of a target system we might not have easy empirical access to. Evidence from an analog model has, under certain strict conditions, been used to argue for the confirmation of a target theory (Unruh (2008), Dardashti et al. (2017)). We investigate what a Bayesian account of such confirmation might require, and illustrate the details by discussing a water-wave analog system of the quantum Casimir effect. We argue that the analogical reasoning involved in this case cannot be sufficiently expressed by traditional Bayesian networks , and therefore employ an extension of (causal) Bayes nets to more capably handle the case study. Our formalization of the concept of analogy provides a novel reconstruction of Bayesian confirmation from ana-log models, which crucially preserves the essential symmetry involved in analogies. Finally, we take our formal analysis of the Casimir effect case to shed new light onto theoretical pre-unification via analogical reasoning.

We describe a superconducting Casimir apparatus inspired by a recently proposed setup involving magnetic surfaces (Bimonte G 2014 Phys. Rev. Lett. 112 240401). The present setup consists of a superconducting Nb sphere and a flat gold... more

We describe a superconducting Casimir apparatus inspired by a recently proposed setup
involving magnetic surfaces (Bimonte G 2014 Phys. Rev. Lett. 112 240401). The present
setup consists of a superconducting Nb sphere and a flat gold plate including in its interior a
superconducting Nb strip. The experimental scheme involves a differential measurement of
the Casimir force at a point of the gold plate above the Nb strip and away from it. We show
that similar to the previous setup, the superconducting system considered here implies widely
different modulations of the Casimir force, depending on whether the thermal force is
computed using the Drude or the plasma model, thus paving the way to an unambiguous
discrimination between these alternative prescriptions.