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The paper presents the band gap computation in one‐ and two‐dimensional photonic crystals built up from porous silicon. The frequency dispersion of the dielectric materials is taken into account.

The behavior of the light in a photonic crystal can be well described by the Maxwell equations. The finite difference time domain (FDTD) method is applied to determine the band structure. The frequency dependence of the dielectric constant is taken into account by a sum of second‐order Lorenz poles. The material parameters are determined applying a conjugate gradient‐based minimization procedure. Passing a light pulse of Gaussian distribution through the photonic crystal and analyzing the transmitted wave can explore the photonic bands.

The realized simulations and visualizations can lead to a much better understanding of the behavior of electromagnetic waves in dispersive photonic crystals, and can make possible to set up experimental conditions properly. The obtained results show again that silicon and porous silicon can be used for the fabrication of photonic crystals.

Due to the high computational requirements of the three‐dimensional case we plan to work out a parallel version of the presented FDTD algorithm.

This paper presents a simple way to take into account the frequency dispersion in the simulation of photonic crystals with the FDTD method.

The Hungarian Revolution of 1956 shook the Soviet Union to the core and provided the West with the iconic image of the freedom fighter willing to risk all for the cause of freedom. The pathos of the lost cause provided Hungarians with a new set of heroes akin to those of the failed 1848 Revolution, the best known being Prime Minister Imre Nagy who was executed for siding with the revolutionaries in their bid to establish a sovereign republic. His belated funeral on June 16, 1989 undermined the moral and political authority of the communist regime that had attempted to consign Nagy and his confederates to oblivion and seemed to mimic Emile Durkheim's analysis of piaculum and the conscience collective. But the spectacle of Nagy's funeral only temporarily shrouded significant differences between and within those factions demanding pluralist society, most recently revealed in the acrimonious celebration of the 50th anniversary of the Hungarian Revolution. These debates are rooted in Hungary's deeply troubled past that strongly questioned republican values in contrast to the authoritarian values of the Hapsburg monarchy, alliance with the Axis, genocide, and its relationship to communism in the wake of the disaster of World War II. Jacques Derrida tells us that it is not easy to exorcise our ghosts; instead, we are prompted to reconstruction. Memory studies, stimulated by studies of the Holocaust, transformed the sociological imagination (especially Friedlander, 1993; LaCapra, 1998a, 1998b, 1998c, 1998d). There has been what Michael Roth referred to as “a turning of oneself so as to be in relation to the past” as an act of witness. The traumatic memory of the 1956 Revolution provides yet another case in which a traumatic past is still salient to the political actors in the contemporary arena. This chapter immerses itself in the emergence of historical sociology and with it “memory studies,” that is: (1) the relationship between identity, memory, and embodiment; and (2) the relationship between historical circumstance and collective memory formation (described in diverse approaches such as Adorno, 1959; 1997; Nora, 1989; Postone, Martha, & Kobyashi 2009). In particular, there is in historical sociology an emergent interest in (1) commemorative practices, memorializing addresses, memento; and (2) the struggles over memory, remembering, and forgetting.