1,260 research outputs found
The origin of scale-scale correlations of the density perturbations during inflation
We show that scale-scale correlations are a generic feature of slow-roll
inflation theories. These correlations result from the long-time tails
characteristic of the time dependent correlations because the long wavelength
density perturbation modes are diffusion-like. A relationship between the
scale-scale correlations and time-correlations is established providing a way
to reveal the time correlations of the perturbations during inflation. This
mechanism provides for a testable prediction that the scale-scale correlations
at two different spatial points will vanish.Comment: Accepted for publication, International Journal of Modern Physics,
vol. 8 No.6 (Dec 1999
Nonabelian Fields in Exact String Solutions
Within the framework of "anomalously gauged" Wess-Zumino-Witten (WZW) models,
we construct solutions which include nonabelian fields. Both compact and
noncompact groups are discussed. In the case of compact groups, as an example
of background containing nonabelian fields, we discuss conformal theory on the
coset, which is the natural generalization of the 2D monopole
theory corresponding to the coset. In noncompact case, we
consider examples with and cosets.Comment: 15 pages, Late
Rapid Thermalization in Field Theory from Gravitational Collapse
Motivated by the duality with thermalization in field theory, we study
gravitational collapse of a minimally coupled massless scalar field in Einstein
gravity with a negative cosmological constant. We investigate the system
numerically and establish that for small values of the initial amplitude of the
scalar field there is no black hole formation, rather, the scalar field
performs an oscillatory motion typical of geodesics in AdS. For large enough
values of the amplitude of the scalar field we find black hole formation which
we detect numerically as the emergence of an apparent horizon. Using the time
of formation as an estimate for thermalization in the field theory we conclude
that thermalization occurs very rapidly, close to the causal bound for a very
wide range of black hole masses. We further study the thermalization time in
more detail as a function of the amplitude and the width of the initial
Gaussian scalar field profile and detect a rather mild structure.Comment: 5 pages, 4 figures. v2: References added, improved most grids by a
factor of 8, main results unchanged. v3 PRD versio
Analisis Pengakuan, Pengukuran dan Pengungkapan Pendapatan dan Beban Berdasarkan PSAK No. 36 pada Ajb Bumiputera 1912 Manado
PSAK No.36 adalah standar akuntansi yang mengatur pendapatan, beban, liabilitas dan aset reasuransi dalam asuransi jiwa. AJB Bumiputera 1912 Manado menerapkan premi selain kontrak jangka pendek, pendapatan lain, klaim telah disetujui, klaim dalam proses penyelesaian dan klaim yang terjadi namun belum dilaporkan, AJB Bumiputera tidak menerapkan pengungkapan catatan atas laporan keuangan dalam Perusahaan dan pengakuan pendapatan premi kontrak jangka pendek. Tujuan penelitian ini untuk mengetahui bagaimana pengakuan, pengukuran dan pengungkapan pendapatan dan beban pada AJB Bumiputera 1912 Manado. Teknik pengumpulan data dilakukan dengan teknik wawancara dan studi pustaka. Menggunakan metode analisis deskriptif, teknik analisis data yaitu membandingkan teori dengan prosedur yang ditetapkan Perusahaan. Hasil penelitian diketahui bahwa manajemen Perusahaan telah menerapkan premi selain jangka pendek, pendapatan lain, dan beban klaim berdasarkan PSAK No.36, juga belum menerapkan premi jangka pendek dan pengungkapan catatan atas laporan keuangan berdasarkan PSAK No.36. Sebaiknya manajemen AJB Bumiputera untuk terus mengikuti standar PSAK No.36 dalam pengakuan, pengukuran dan pengungkapan pendapatan dan beban pada asuransi jiwa. Kata kunci : pengakuan, pengukuran, pengungkapan, pendapatan, beba
Optimal frequency-response sensitivity of compressible flow over roughness elements
Compressible flow over a flat plate with two localised and well-separated roughness elements is analysed by global frequency-response analysis. This analysis reveals a sustained feedback loop consisting of a convectively unstable shear-layer instability, triggered at the upstream roughness, and an upstream-propagating acoustic wave, originating at the downstream roughness and regenerating the shear-layer instability at the upstream protrusion. A typical multi-peaked frequency response is recovered from the numerical simulations. In addition, the optimal forcing and response clearly extract the components of this feedback loop and isolate flow regions of pronounced sensitivity and amplification. An efficient parametric-sensitivity framework is introduced and applied to the reference case which shows that first-order increases in Reynolds number and roughness height act destabilising on the flow, while changes in Mach number or roughness separation cause corresponding shifts in the peak frequencies. This information is gained with negligible effort beyond the reference case and can easily be applied to more complex flows
Scientific Bounty Among Meteorites Recovered from the Dominion Range, Transantarctic Mountains
The US Antarctic Meteorite Pro-gram has visited the Dominion Range in the Transantarctic Mountains during several different sea-sons, including 1985, 2003, 2008, 2010, 2014 and 2018. Total recovered meteorites from this region is close to 3000. The 1985 (11 samples), 2003 (141 samples), 2008 (521 samples), 2010 (901 samples), 2014 (562 samples) seasons have been fully classified, and 2018 (865 samples) are in the process of being classified and characterized. Given that close to 2200 samples have been classified so far, with more expected in 2020, now is a good time to summarize the state of the collection. Here we describe the significant samples documented from this area, as well as a large meteorite shower that dominates the statistics of the region
Tensions and Luscher Terms for (2+1)-dimensional k-strings from Holographic Models
The leading term for the energy of a bound state of k-quarks and k-antiquarks
is proportional to its separation L. These k-string configurations have a
Luscher term associated with their quantum fluctuations which is typically a
1/L correction to the energy. We review the status of tensions and Luscher
terms in the context of lattice gauge theory, Hamiltonian methods, and
gauge/gravity correspondence. Furthermore we explore how different
representations of the k-string manifest themselves in the gauge/gravity
duality. We calculate the Luscher term for a strongly coupled SU(N) gauge
theory in (2+1) dimensions using the gauge/gravity correspondence. Namely, we
compute one-loop corrections to a probe D4-brane embedded in the Cvetic,
Gibbons, Lu, and Pope supergravity background. We investigate quantum
fluctuations of both the bosonic and the fermionic sectors.Comment: 39 pages, reference added, same version to be published in JHE
Black Holes in Cascading Theories: Confinement/Deconfinement Transition and other Thermal Properties
We present numerical evidence for a transition between the Klebanov-Strassler
background and a solution describing a black hole in the class of cascading
solutions in the chirally restored phase. We also present a number of
properties of this solution, including the running of the coupling constant,
the viscosity to entropy ratio and the drag force on a quark moving in this
background.Comment: 34 pages, 7 figures. Version to be published by JHE
Antarctic Meteorites: A Statistical Look at a Uniquely Valuable Resource
As of the end of the 2018-19 field season, the U.S. Antarctic meteorite program has surpassed 23,000 meteorites collected. The U.S. collection is valuable in that it is classified in its entirety. The systematic methods employed to collect the meteorites have provided meteorites of more than 40 types, many of which are the first of their type ever recognized. One of the early drivers for consistent and methodical characterization of the entire U.S. Antarctic collection was to allow statistical comparisons. Early statistical assessments of the U.S. Antarctic collection examined mass distributions and the relative frequency of meteorite types as well as comparisons to a defined set of modern falls. Using these statistics argued that the flux of H chondrites changed over time used model size distributions to deconstruct the contribution of wind movement, meteorite supply and search losses to the Antarctic collection. Mass-based statistics and size distribution comparisons were examined by investigated various aspects of the statistics, including comparison with modern falls/Saharan finds. Also discuss geospatial statistics provides a comprehensive overview of the statistics of the Antarctic collections for the first 35 seasons of U.S. collection by ANSMET. Here we build upon that assessment and that from
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