447 research outputs found
Non-Detection of X-Ray Emission From Sterile Neutrinos in Stacked Galaxy Spectra
We conduct a comprehensive search for X-ray emission lines from sterile
neutrino dark matter, motivated by recent claims of unidentified emission lines
in the stacked X-ray spectra of galaxy clusters and the centers of the Milky
Way and M31. Since the claimed emission lines lie around 3.5 keV, we focus on
galaxies and galaxy groups (masking the central regions), since these objects
emit very little radiation above keV and offer a clean background
against which to detect emission lines. We develop a formalism for maximizing
the signal-to-noise of decaying dark matter emission lines by weighing each
X-ray event according to the expected dark matter profile. In total, we examine
81 and 89 galaxies with Chandra and XMM-Newton respectively, totaling 15.0 and
14.6 Ms of integration time. We find no significant evidence of any emission
lines, placing strong constraints on the mixing angle of sterile neutrinos with
masses between 4.8-12.4 keV. In particular, if the 3.57 keV feature from Bulbul
et al. (2014) were due to 7.1 keV sterile neutrino emission, we would have
detected it at and in our two samples. The most
conservative estimates of the systematic uncertainties reduce these constraints
to and 7.8, or letting the line energy vary between 3.50
and 3.60 keV reduces these constraints to and
respectively. Unlike previous constraints, our measurements do not depend on
the model of the X-ray background or on the assumed logarithmic slope of the
center of the dark matter profile.Comment: accepted to MNRA
The Social and Political Conflict in Prussia 1858-1864
T HE present study developed out of a desire to understand the character of liberalism and conservatism in Prussia on the eve of German unification. Who were the liberals? Who were the Conservatives? What were their ideals and how did they conduct themselves in public? How powerful was each group in the state? In conflict throughout the Nineteenth Century, the opponents reached the peak of their antagonism in the years between 1858 and 1866, the the years of the New Era, the constitutional conflict, and the first two wars of German unification. Fundamental social, economic, and political ideals were at stake. One group would have aligned the country with the West; the other sought to preserve the Old Regime. Since the story of Bismarck\u27s crushing defeat of the liberals by his Realpolitik after 1864 is well known, the present analysis concentrates upon the internal crisis of 1858 to 1864 within Prussia; and in keeping with the nature of the subject, the method of treatment is topical rather than chronological. Analyses of social and institutional forces in conflict in the past century and a half should be made for each of the European countries. The Old Regime survived over much of the continent well into the Twentieth Century, and controversies like the one in Prussia occurred in every state. The present study can be justified not merely as a treatment of a crucial period in German history but as an essential chapter in the history of modern Europe. It should help toward making possible a comparative analysis of society and institutions in the modern world, by means of which we should, for example, be able to explain the remarkable difference between the course of development of Europe and that of the United States.
IN 1858 King Frederick William IV of Prussia became mentally deranged and had to relinquish the royal authority to his brother, Prince William. The Regent quickly ousted most of the Conservatives in the ministry and appointed right-wing liberals in their stead. The people of Prussia interpreted the Regent\u27s words and actions as an indication of liberalism. In the elections to the Lower House of the Landtag in the next year they threw out the Conservative majority in favor of the liberals. During the course of the next three years, popularly called the New Era because of the hope for the liberal refornl of Prussia and the national unification of Germany, the ruler and the liberal majority learned to their dismay that each wished something different from the other. The former harbored two aims, to reform and strengthen the army and to keep his absolute power, while the latter was equally determined to reform Prussia in a liberal sense and to unify Germany. Both William and the liberals confused reality with desire. The Prince thought that he was governing a Prussia like that of his beloved father, Frederick William III (d. 1840), but actually he faced a state in which society had considerably altered. The liberals believed that the Regent appreciated the needs of the time and could be led or pushed into a movement of reform. Through initial misunderstanding and subsequent refusal to compromise they drifted by 1862 into a constitutional conflict. The ruler, who became King on the death of his brother in January, 1861, dismissed the liberal ministers in the next year, again turned to the Conservatives, and in September, 1862, appointed Bismarck as Minister President. The selection of this Junker statesman signified that the controversy over the meaning of the constitution would be resolved by Machtpolitik. In spite of the fact that the elections to the Lower House in 1861 and in 1862 had almost eliminated the Conservatives, the government, through the exercise of all possible pressure upon the voters, tried in 1863 to replace the overwhelming liberal majority by Conservatives. The attempt failed; but the King and his Conservative ministers continued to rule, and as a result of their successful resistance to the liberals they imparted to the constitution the absolutistic interpretation that they wished. Apparently so promising at the beginning of the New Era, liberalism went down to crushing defeat. How did the conflict between the liberals on the one hand and the King and the Conservatives on the other come about? An explanation involves, first, a portrayal of the ruler\u27s character, second, a comparison between his aims and those of the liberals, and third, a summary of the economic and social changes that had occurred in Prussia since the formative years of the new ruler\u27s youth
Process versus Power: Studies in Modern Culture
The essays in this volume are concerned with the culture of a period of profound change. They are intended to serve the practical purpose of estimating what is the present state of our culture, what are its potentialities, and what are the major obstacles to the achievement of a good life. They deal above all with the problem of the character and the enemies of our industrial culture, in the hope of counteracting pessimism caused by desire for immediate perfection.
We live in a period of such cultural diversity as man has never known. Within the past half century or less we have participated in the destruction of almost all the social organizations surviving from the Old Regime of the Eighteenth Century; we have seen develop and function the systems of Communism, Fascism and Nazism, together with numerous other authoritarian variants; we have grown acutely aware of the existence of primitive societies in Europe as well as elsewhere, of societies composed of almost self-dependent agricultural localities; we have experienced the unique process of industrialization and seen the elaboration of the social and institutional bases for a culture of freedom such as not even the Athens of Pericles could have imagined. Industrialism, two world wars, and a world economic depression have brought these cultures into such intimate contact that an understanding and evaluation of each type becomes not merely an intellectual exercise but a practical necessity. Supplementing the variety of cultures in the modern period has been the diversity of speed of action. Events have never proceeded at a faster tempo. The machine process, power politics and war and revolution have accelerated the rate of change to a degree to which so far man has been unable to adapt himself and remain in control of the course of events. Some parts of the transformation, like that of the establishment of the Bolshevik regime in Russia, escaped the influence of the overwhelming majority of society; before man was aware of the fact, a new and hostile culture had been founded. Man has acquired his habits of social behavior in the slow, even tempo of an agrarian culture. While crises did occur in that kind of society, they came at infrequent intervals and allowed much more time for adjustment than we have had at our disposal. One of the most startling facts about our age is the contrast between the social implication of the peaceful, steady, slow rate of change of a Victorian England and that of the furious rate of cultural crisis like the one of this century. We have to recognize the basic significance of rate of change in conditioning the character of a situation. There is such a thing as a cultural crisis, and it evokes qualities and types of action different from those of a peaceful period
The Social and Political Conflict in Prussia 1858-1864
T HE present study developed out of a desire to understand the character of liberalism and conservatism in Prussia on the eve of German unification. Who were the liberals? Who were the Conservatives? What were their ideals and how did they conduct themselves in public? How powerful was each group in the state? In conflict throughout the Nineteenth Century, the opponents reached the peak of their antagonism in the years between 1858 and 1866, the the years of the New Era, the constitutional conflict, and the first two wars of German unification. Fundamental social, economic, and political ideals were at stake. One group would have aligned the country with the West; the other sought to preserve the Old Regime. Since the story of Bismarck\u27s crushing defeat of the liberals by his Realpolitik after 1864 is well known, the present analysis concentrates upon the internal crisis of 1858 to 1864 within Prussia; and in keeping with the nature of the subject, the method of treatment is topical rather than chronological. Analyses of social and institutional forces in conflict in the past century and a half should be made for each of the European countries. The Old Regime survived over much of the continent well into the Twentieth Century, and controversies like the one in Prussia occurred in every state. The present study can be justified not merely as a treatment of a crucial period in German history but as an essential chapter in the history of modern Europe. It should help toward making possible a comparative analysis of society and institutions in the modern world, by means of which we should, for example, be able to explain the remarkable difference between the course of development of Europe and that of the United States.
IN 1858 King Frederick William IV of Prussia became mentally deranged and had to relinquish the royal authority to his brother, Prince William. The Regent quickly ousted most of the Conservatives in the ministry and appointed right-wing liberals in their stead. The people of Prussia interpreted the Regent\u27s words and actions as an indication of liberalism. In the elections to the Lower House of the Landtag in the next year they threw out the Conservative majority in favor of the liberals. During the course of the next three years, popularly called the New Era because of the hope for the liberal refornl of Prussia and the national unification of Germany, the ruler and the liberal majority learned to their dismay that each wished something different from the other. The former harbored two aims, to reform and strengthen the army and to keep his absolute power, while the latter was equally determined to reform Prussia in a liberal sense and to unify Germany. Both William and the liberals confused reality with desire. The Prince thought that he was governing a Prussia like that of his beloved father, Frederick William III (d. 1840), but actually he faced a state in which society had considerably altered. The liberals believed that the Regent appreciated the needs of the time and could be led or pushed into a movement of reform. Through initial misunderstanding and subsequent refusal to compromise they drifted by 1862 into a constitutional conflict. The ruler, who became King on the death of his brother in January, 1861, dismissed the liberal ministers in the next year, again turned to the Conservatives, and in September, 1862, appointed Bismarck as Minister President. The selection of this Junker statesman signified that the controversy over the meaning of the constitution would be resolved by Machtpolitik. In spite of the fact that the elections to the Lower House in 1861 and in 1862 had almost eliminated the Conservatives, the government, through the exercise of all possible pressure upon the voters, tried in 1863 to replace the overwhelming liberal majority by Conservatives. The attempt failed; but the King and his Conservative ministers continued to rule, and as a result of their successful resistance to the liberals they imparted to the constitution the absolutistic interpretation that they wished. Apparently so promising at the beginning of the New Era, liberalism went down to crushing defeat. How did the conflict between the liberals on the one hand and the King and the Conservatives on the other come about? An explanation involves, first, a portrayal of the ruler\u27s character, second, a comparison between his aims and those of the liberals, and third, a summary of the economic and social changes that had occurred in Prussia since the formative years of the new ruler\u27s youth
Crossroads of Cuisine
Crossroads of Cuisine provides a history of foods, and foodways in terms of exchanges taking place in Central Asia and in surrounding areas such as China, Korea or Iran during the last 5000 years, stressing the manner in which East and West, West and East grew together through food. It provides a discussion of geographical foundations, and an interlocking historical and cultural overview going down to the present day, with a comparative country by country survey of foods and recipes. An ethnographic photo essay embracing all parts of the book binds it all together, and helps make topics discussed vivid and approachable. The book is important for explaining key relationships that have not always been made clear in past scholarship
Theoretical and experimental infrared spectra of hydrated and dehydrated sulfonated poly(ether ether ketone)
Time-dependent FT-IR spectra of sulfonated poly(ether ether ketone) during dehydration show diminishing 1081 cm−1 and 1023 cm−1 band intensities concurrent with the emergence and shifting of bands at 1362 cm−1 and 898 cm−1. Animations of density functional theory calculated normal modes enable assignment of the 1081 cm−1 and 1023 cm−1 bands as group modes that include a sulfonate exchange site with C3v local symmetry, while the 1362 cm−1 and 898 cm−1 bands are assigned as group modes that include an associated sulfonic acid with no local symmetry (C1). In contrast to analogously assigned Nafion group mode bands, the SPEEK C3v and C1 bands coexist throughout the entire dehydration–hydration cycle, suggesting the presence of associated and dissociated exchange sites in SPEEK at all states-of-hydration. This supports a morphological model for SPEEK featuring branched hydrophilic domains and dead-end aqueous confines
Non-Fermi Liquid Behavior In Quantum Critical Systems
The problem of an electron gas interacting via exchanging transverse gauge
bosons is studied using the renormalization group method. The long wavelength
behavior of the gauge field is shown to be in the Gaussian universality class
with a dynamical exponent in dimensions .
This implies that the gauge coupling constant is exactly marginal. Scattering
of the electrons by the gauge mode leads to non-Fermi liquid behavior in . The asymptotic electron and gauge Green's functions, interaction
vertex, specific heat and resistivity are presented.Comment: 9 pages in REVTEX 2.0. Submitted to Phys. Rev. Lett. 3 figures in
postscript files can be obtained at [email protected]. The filename is
gan.figures.tar.z and it's compressed. You can uncompress it by using
commands: "uncompress gan.figures.tar.z" and "tar xvf gan.figures.tar
Pi excitation of the t-J model
In this paper, we present analytical and numerical calculations of the pi
resonance in the t-J model. We show in detail how the pi resonance in the
particle-particle channel couples to and appears in the dynamical spin
correlation function in a superconducting state. The contribution of the pi
resonance to the spin excitation spectrum can be estimated from general
model-independent sum rules, and it agrees with our detailed calculations. The
results are in overall agreement with the exact diagonalization studies of the
t-J model. Earlier calculations predicted the correct doping dependence of the
neutron resonance peak in the YBCO superconductor, and in this paper detailed
energy and momentum dependence of the spin correlation function is presented.
The microscopic equations of motion obtained within current formalism agree
with that of the SO(5) nonlinear sigma model, where the pi resonance is
interpreted as a pseudo Goldstone mode of the spontaneous SO(5) symmetry
breaking.Comment: 33 pages, LATEX, 14 eps fig
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