3,409 research outputs found
Adorno’s Critique of the New Right-Wing Extremism: How (Not) to Face the Past, Present, and Future
This paper serves three purposes relating to a lecture Adorno gave in 1967 on “the new right-wing extremism” that was on the rise then in West Germany; in 2019, the lecture was published in print for the first time in German, to wide acclaim, followed by an English translation that appeared in 2020. First, it is important to situate the lecture in its historical and political context, and to relate it to Adorno’s status as a critical theorist in West Germany. Secondly, Adorno’s diagnosis of the new right-wing extremism (and related forms of populism) and his conclusions about how to resist and counteract it are relevant to the current political situation in the United States, even though he presented his analysis more than half a century ago. Thirdly, Adorno’s lecture provided the model for a type of education that is oriented toward enabling students to face unpleasant facts about modern social life in constructive ways, including recognizing and resisting right-wing populism and extremism, in an age that imposes greater and greater uncertainty and challenges on individuals. In conclusion, it is evident that in a rapidly changing world, the “tricks” of right-wing populists and extremists are astonishingly unoriginal and static, which in part may explain their appeal and effectiveness. Reading the pedagogy Adorno suggested as a practical application of his critical theory highlights the importance of enabling individuals to recognize the “normalcy” of proliferating experiences of cognitive dissonance, and to respond to such experiences by adopting a productive rather than defeatist stance with regard to the increasing complexity and the intensifying contradictions of modern societies in the twenty-first century, as they are accompanied by myriad possibilities and threats
Stable superhydrophobic aluminum surfaces based on laser-fabricated hierarchical textures
Laser-microtextured surfaces have gained an increasing interest due to their enormous spectrum of applications and industrial scalability. Direct laser interference patterning (DLIP) and the well-established direct laser writing (DLW) methods are suitable as a powerful combination for the fabrication of single (DLW or DLIP) and multi-scale (DLW+DLIP) textures. In this work, four-beam DLIP and DLW were used independently and combined to produce functional textures on aluminum. The influence of the laser processing parameters, such as the applied laser fluence and the number of pulses, on the resulting topography was analyzed by confocal microscopy and scanning electron microscopy. The static long-term and dynamic wettability characteristics of the laser-textured surfaces were determined through water contact angle and hysteresis measurements, revealing superhydrophobic properties with static contact angles up to 163° and hysteresis as low as 9°. The classical Cassie-Baxter and Wenzel models were applied, permitting a deeper understanding of the observed wetting behaviors. Finally, mechanical stability tests revealed that the DLW elements in the multi-scale structure protects the smaller DLIP features under tribological conditions.Fil: Milles, Stephan. Technische Universität Dresden; AlemaniaFil: Dahms, Johannes. Technische Universität Dresden; AlemaniaFil: Soldera, Marcos Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Lasagni, Andrés F.. Technische Universität Dresden; Alemani
Heavy-flavor dynamics in nucleus-nucleus collisions: from RHIC to LHC
The stochastic dynamics of c and b quarks in the fireball created in
nucleus-nucleus collisions at RHIC and LHC is studied employing a relativistic
Langevin equation, based on a picture of multiple uncorrelated random
collisions with the medium. Heavy-quark transport coefficients are evaluated
within a pQCD approach, with a proper HTL resummation of medium effects for
soft scatterings. The Langevin equation is embedded in a multi-step setup
developed to study heavy-flavor observables in pp and AA collisions, starting
from a NLO pQCD calculation of initial heavy-quark yields, complemented in the
nuclear case by shadowing corrections, k_T-broadening and nuclear geometry
effects. Then, only for AA collisions, the Langevin equation is solved
numerically in a background medium described by relativistic hydrodynamics.
Finally, the propagated heavy quarks are made hadronize and decay into
electrons. Results for the nuclear modification factor R_AA of heavy-flavor
hadrons and electrons from their semi-leptonic decays are provided, both for
RHIC and LHC beam energies.Comment: 4 pages, 2 figures (3 eps files); submitted for publication in the
proceedings of "Quark Matter 2011", 23-28 May 2011, Annecy (France
Direct photons ~basis for characterizing heavy ion collisions~
After years of experimental and theoretical efforts, direct photons become a
strong and reliable tool to establish the basic characteristics of a hot and
dense matter produced in heavy ion collisions. The recent direct photon
measurements are reviewed and a future prospect is given.Comment: 8 pages, 8 figures, Invited plenary talk at Quark Matter 200
Symmetry-breaking transitions in networks of nonlinear circuit elements
We investigate a nonlinear circuit consisting of N tunnel diodes in series,
which shows close similarities to a semiconductor superlattice or to a neural
network. Each tunnel diode is modeled by a three-variable FitzHugh-Nagumo-like
system. The tunnel diodes are coupled globally through a load resistor. We find
complex bifurcation scenarios with symmetry-breaking transitions that generate
multiple fixed points off the synchronization manifold. We show that multiply
degenerate zero-eigenvalue bifurcations occur, which lead to multistable
current branches, and that these bifurcations are also degenerate with a Hopf
bifurcation. These predicted scenarios of multiple branches and degenerate
bifurcations are also found experimentally.Comment: 32 pages, 11 figures, 7 movies available as ancillary file
Dynamics of fully coupled rotators with unimodal and bimodal frequency distribution
We analyze the synchronization transition of a globally coupled network of N
phase oscillators with inertia (rotators) whose natural frequencies are
unimodally or bimodally distributed. In the unimodal case, the system exhibits
a discontinuous hysteretic transition from an incoherent to a partially
synchronized (PS) state. For sufficiently large inertia, the system reveals the
coexistence of a PS state and of a standing wave (SW) solution. In the bimodal
case, the hysteretic synchronization transition involves several states.
Namely, the system becomes coherent passing through traveling waves (TWs), SWs
and finally arriving to a PS regime. The transition to the PS state from the SW
occurs always at the same coupling, independently of the system size, while its
value increases linearly with the inertia. On the other hand the critical
coupling required to observe TWs and SWs increases with N suggesting that in
the thermodynamic limit the transition from incoherence to PS will occur
without any intermediate states. Finally a linear stability analysis reveals
that the system is hysteretic not only at the level of macroscopic indicators,
but also microscopically as verified by measuring the maximal Lyapunov
exponent.Comment: 22 pages, 11 figures, contribution for the book: Control of
Self-Organizing Nonlinear Systems, Springer Series in Energetics, eds E.
Schoell, S.H.L. Klapp, P. Hoeve
Towards net zero CO2 in 2050: an emission reduction pathway for organic soils in Germany
The Paris Agreement reflects the global endeavour to limit the increase of global average temperature to 2 °C, better 1.5 °C above pre-industrial levels to prevent dangerous climate change. This requires that global anthropogenic net carbon dioxide (CO2) emissions are reduced to zero around 2050. The German Climate Protection Plan substantiates this goal and explicitly mentions peatlands, which make up 5 % of the total area under land use and emit 5.7 % of total annual greenhouse gas emissions in Germany. Based on inventory reporting and assumptions of land use change probability, we have developed emission reduction pathways for organic soils in Germany that on a national level comply with the IPCC 1.5 °C pathways. The more gradual pathway 1 requires the following interim (2030, 2040) and ultimate (2050) milestones: Cropland use stopped and all Cropland converted to Grassland by 2030; Water tables raised to the soil surface on 15 % / 60 % / 100 % of all Grassland, on 50 % / 75 % / 100 % of all Forest land, and ultimately on 2/3 of all Settlements and on 100 % of all Wetlands. Also a more direct pathway 2 without interim ‘moist’ water tables and the climate effect (radiative forcing) of different scenarios is presente
e+e- Pairs: a clock and a thermometer of heavy ion collisions
Recently, there is growing evidence that a new state of matter is formed in
sqrt(s_NN)= 200 GeV Au+Au collisions at RHIC: a strongly coupled Quark Gluon
Plasma of partonic degrees of freedom which develops a collective motion.
Dilepton spectra are not affected by strong interaction and can therefore probe
the whole time evolution of the collision. Thus they may be sensitive to onset
of deconfinement, chiral symmetry restoration, as well as the production of
thermal photons. The PHENIX experiment measured the production of e+e- pairs in
p+p and Au+Au collisions at sqrt(s_NN)= 200 GeV. An enhanced dilepton yield in
the mass range 150<m_ee<750 MeV/c^2 is measured. The excess increases faster
with centrality than the number of participating nucleons and is concentrated
at p_T<1GeV/c. At higher p_T the excess below 300 MeV/c^2 has been related to
an enhanced production of direct photons possibly of thermal origin.Comment: Proceedings of Quark Matter 2008, 8 pages, 7 figure
- …