14,588 research outputs found
Mistaken Identity and Mirror Images: Albert and Carl Einstein, Leiden and Berlin, Relativity and Revolution
Albert Einstein accepted a 'special' visiting professorship at the University
of Leiden in the Netherlands in February 1920. Although his appointment should
have been a mere formality, it took until October of that year before Einstein
could occupy his special chair. Why the delay? The explanation involves a case
of mistaken identity with Carl Einstein, Dadaist art, and a particular Dutch
fear of revolutions. But what revolution was one afraid of? The story of
Einstein's Leiden chair throws new light on the reception of relativity and its
creator in the Netherlands and in Germany
Reactionaries and Einstein's Fame: "German Scientists for the Preservation of Pure Science," Relativity, and the Bad Nauheim Meeting
Two important and unpleasant events occurred in Albert Einstein's life in
1920: That August an antirelativity rally was held in the large auditorium of
the Berlin Philharmonic, and a few weeks later Einstein was drawn into a tense
and highly publicized debate with Philipp Lenard on the merits of relativity at
a meeting in Bad Nauheim, Germany. I review these events and discuss how they
affected Einstein in light of new documentary evidence that has become
available through the publication of Volume 10 of the Collected Papers of
Albert Einstein.Comment: 18 page
The reception of relativity in the Netherlands
This article reviews the early academic and public reception of Albert
Einstein's theory of relativity in the Netherlands, particularly after Arthur
Eddington's eclipse experiments of 1919. Initially, not much attention was
given to relativity, as it did not seem an improvement over Hendrik A. Lorentz'
work. This changed after the arrival in Leiden of Paul Ehrenfest. Soon
relativity was much studied and lead to controversy among a number of
conservative intellectuals, as elsewhere in Europe. The tone of Dutch critics
was much more mild, however. This can be understood when one considers Dutch
neutrality during World War I. Einstein's political positions were generally
positively perceived in Holland, which Dutch academics put to use in their
efforts at international reconciliation abroad, and the presentation of
theoretical physics at home
Break it Down: An Alternative Approach to Measuring Effectiveness in Counterterrorism
This paper will review the ways in which the effectiveness of counterterrorism measures and policies has been assessed and argue that they suffer largely from the same difficulties. For many of the chosen indicators it is not clear whether they represent what they are supposed to represent and whether shifts in the scores can be attributed to counterterrorism. After having discussed these problems, a different way of measuring counterterrorism effectiveness is outlined. It rests on the assumption that counterterrorism should be broken down into separate components that should all be evaluated separately. For all components, a causal chain from cause (measure) to effect (shift in indicator) should be formulated to solve the meaning and attribution problems.
On Einstein's opponents, and other crackpots
Essay Review of "Einsteins Gegner. Die \"offentliche Kontroverse um die
Relativit\"atstheorie in den 1920er Jahren" by Milena Wazeck.Comment: 6 page
Production and persistency of red clover (Trifolium pratense) varieties when grown in mixtures
In the Netherlands organic and conventional dairy farmers are taking an increasing interest in grass and red clover mixtures for ley pastures (cutting only). A constraint to the adoption of such mixtures is the persistency of the red clover (Trifolium pratense L.) varieties presently used in the Netherlands; Rotra, Barfiola, Violetta and Merviot. The latter being the most persistent under practical circumstances. Testing of red clover varieties in Switzerland showed a high degree of persistency of the so-called ‘mattenklee’ varieties such as Astur and Pica (Suter et al., 2004). We compared eight red clover varieties including 2 ‘mattenklee’ varieties in mixtures with perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), and a mixture containing white clover and perennial ryegrass only.
Red clover mixtures out yielded the white clover mixtures by 5.4 t dry matter (DM) ha -1 . ULC 1715186 and Astur were the most productive red clover varieties. The development of the clover content of Astur showed that this variety scored highest on persistency
Scalable discovery of hybrid process models in a cloud computing environment
Process descriptions are used to create products and deliver services. To lead better processes and services, the first step
is to learn a process model. Process discovery is such a technique which can automatically extract process models from event logs.
Although various discovery techniques have been proposed, they focus on either constructing formal models which are very powerful
but complex, or creating informal models which are intuitive but lack semantics. In this work, we introduce a novel method that returns
hybrid process models to bridge this gap. Moreover, to cope with today’s big event logs, we propose an efficient method, called f-HMD,
aims at scalable hybrid model discovery in a cloud computing environment. We present the detailed implementation of our approach
over the Spark framework, and our experimental results demonstrate that the proposed method is efficient and scalabl
Orbital-selective Mott transitions in two-band Hubbard models
The anisotropic two-orbital Hubbard model is investigated at low temperatures
using high-precision quantum Monte Carlo (QMC) simulations within dynamical
mean-field theory (DMFT). We demonstrate that two distinct orbital-selective
Mott transitions (OSMTs) occur for a bandwidth ratio of 2 even without
spin-flip contributions to the Hund exchange, and we quantify numerical errors
in earlier QMC data which had obscured the second transition. The limit of
small inter-orbital coupling is introduced via a new generalized Hamiltonian
and studied using QMC and Potthoff's self-energy functional method, yielding
insight into the nature of the OSMTs and the non-Fermi-liquid OSM phase and
opening the possibility for a new quantum-critical point.Comment: 2 pages, 4 figures, presented at ICM2006 and accepted for JMM
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