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4: Example of "invisibility" achieved through a hall of mirrors. An object placed in the concealed region, between the observer and the apple, would be not visible.
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Metamaterials are artificial materials, made by microscopic unit cells and projected to exhibit specific macroscopic properties, e.g. they can be designed in order to show a negative refractive index or a superluminal wave propagation. During the last decade, the interest in electromagnetic
metamaterials has been grown because of their possible app...
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Finite-difference is the most popular method to illustrate the wave propagation in elastic media. By using it, we can freely manipulate the discrete number as a waveform in our domain model. In this paper, we try to explain clearly, step by step, from source excitation, main scheme, parameterization, stability condition, until results. The combinat...
Citations
... circulating currents), and thus an arbitrary-high dynamic-resistivity can be installed also within highly-conducting substrates. This behaviour is one of the most important differences between circuit and antenna-theory (see [Gonano, 2015]). ...
... When a material analysis readily constrains the orientation of the electric field along an internal boundary in a time-independent fashion, maxwell's equations provide a tool for understanding how currents have to flow in order to fulfil the known boundary-conditions (for a detailed analysis of electromagnetic boundary-conditions and their implication, consult [Gonano, 2015]). ...
... • In accordance to the previous point, and considering that spines the interior volume of the spines is patterned by a nano-metric actin mesh (see [Patirniche et al., 2018]), spines can be treated as photonic crystals, since their resonant spectrum lies in the optical regime (see [Joannopoulos et al., 2011]). the form of an actin cytoskeleton, having a much finer geometric structure (see [Patirniche et al., 2018]), dendritic spines (and in fact all cells) can be classified as metamaterials (see [Gonano, 2015]). This means that not only are spines resonating at optical frequencies, but when they do, the solid volumetric cytoskeletal mesh that maintains their shape, will introduce supplemental resonating modes. ...
Living beings are finite, self-sustaining, material architectures, capable of executing directed functions. Since both the architectural, as well as the behavioural (i.e. dynamic) aspects of living beings are highly stereotypical, we first introduce a geometric framework that is able to capture the natural organisation of living beings, to then inspect basic electrical events known to occur in-vivo, aided by the introduced constructs. Within this manuscript, a formal attempt is thus made to express the global dynamics occurring within living beings in an ontologically-consistent manner. From this perspective, multicellular organisms appear to function as nested electromagnetic systems, suggesting that indeed, neuronal architectures are much more complex than the usually ascribed cables, namely intricately-patterned, and therefore highly-exotic antennae. The basic mechanism that we investigate is the excitatory synaptic transmission process, involving three distinct compartments: a presynaptic axon along which an ordinary electrical pulse is transported, a postsynaptic cell with which the axon forms a synapse, and the extracellular space engulfing these two cells. Assuming that during this dynamical event neurotransmitters are released when the action potential is in the vicinity of the synapse, leading to the opening of ion-channels in the postsynaptic cell, Maxwell's equations predict a fundamentally different electrical regime than what is commonly described in textbooks. As such, we follow this route and discuss some immediate implications that result from treating biological organisms as a hierarchy of nested antennae, without appealing to stochastic events, thereby providing a fully deterministic perspective on biological processes.
Neuroscience often assumes that the electrical events in the brain are well described with an electrostatic formalism. However, by adopting a geometric attitude and observing a propagating action potential, it becomes immediately clear that inductive effects are to be expected at the synaptic level, inviting thus to ponder about the possible electromagnetic effects unfolding within any living being.
