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This is the draft version of a textbook on "real-world" applications of the AdS/CFT duality for beginning graduate students in particle physics and for researchers in the other fields. The aim of this book is to provide background materials such as string theory, general relativity, nuclear physics, nonequilibrium physics, and condensed-matter physics as well as some key applications of the AdS/CFT duality in a single textbook. Contents: (1) Introduction, (2) General relativity and black holes, (3) Black holes and thermodynamics, (4) Strong interaction and gauge theories, (5) The road to AdS/CFT, (6) The AdS spacetime, (7) AdS/CFT - equilibrium, ( AdS/CFT - adding probes, (9) Basics of nonequilibrium physics, (10) AdS/CFT - nonequilibrium, (11) Other AdS spacetimes, (12) Applications to quark-gluon plasma, (13) Basics of phase transition, (14) AdS/CFT - phase transition.
Weyl-invariant extensions of three-dimensional New Massive Gravity, generic n-dimensional Quadratic Curvature Gravity theories and three-dimensional Born-Infeld gravity theory are analyzed in details. As required by Weyl-invariance, the actions of these gauge theories do not contain any dimensionful parameter hence the local symmetry is spontaneously broken in (Anti) de Sitter vacua in complete analogy with the Standard Model Higgs mechanism. In flat vacuum, symmetry breaking mechanism is more complicated: The dimensionful parameters come from dimensional transmutation in the quantum field theory; therefore, the conformal symmetry is radiatively broken (at two loop level in 3-dimensions and at one-loop level in 4-dimensions) \`{a} la Coleman-Weinberg mechanism. In the broken phases, save for New Massive Gravity, the theories generically propagate with a unitary (tachyon and ghost-free) massless tensor, massive (or massless) vector and massless scalar particles for the particular intervals of the dimensionless parameters. For New Massive Gravity, there is a massive Fierz-Pauli-type graviton. Finally, it is shown that n-dimensional Weyl-invariant Einstein-Gauss-Bonnet theory is the only unitary higher dimensional Weyl-invariant Quadratic Curvature Gravity theory.
We apply a homogenization process to the acoustic velocity potential wave equation. The study of various examples shows that the resulting effective properties are different from those of the homogenized pressure wave equation for the same underlying acoustic parameters. A careful analysis reveals that a given set of inhomogeneous parameters represents an entirely different physical system depending on the considered equation. Our findings unveil a different way of tailoring acoustic properties through gradients of the static pressure. In contrast to standard metafluids based on isobaric composites, this alternative kind of metafluids is suitable for the implementation of transformational devices designed via the velocity potential equation. This includes acoustic systems in a moving background or arising from general space-time transformations. As an example, we design a device able to cloak the acoustic velocity potential.
Цитата и на BICEP2 грав волны нашли Мужики сумлеваются
и на BICEP2 грав волны нашли
We investigate the prior dependence on the inferred spectrum of primordial tensor perturbations, in light of recent results from BICEP2 and taking into account a possible dust contribution to polarized anisotropies. We highlight an optimized parameterization of the tensor power spectrum, and adoption of a logarithmic prior on its amplitude AT, leading to results that transform more evenly under change of pivot scale. In the absence of foregrounds the tension between the results of BICEP2 and Planck drives the tensor spectral index nT to be blue-tilted in a joint analysis, which would be in contradiction to the standard inflation prediction (nT<0). When foregrounds are accounted for, the BICEP2 results no longer require non-standard inflationary parameter regions. We present limits on primordial AT and nT, adopting foreground scenarios put forward by Mortonson & Seljak and motivated by Planck 353 GHz observations, and assess what dust contribution leaves a detectable cosmological signal. We find that if there is sufficient dust for the signal to be compatible with standard inflation, then the primordial signal is too weak to be robustly detected by BICEP2 if Planck+WMAP upper limits from temperature and E-mode polarization are correct.
Tensors, BICEP2, prior dependence, and dust
Это новая работа по исследованию гравитации?
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum Cosmology (gr-qc)
По существу: открывает закрытый (утвердительно) вопрос о существовании гравитационных волн.
Ну да, можно и так рассудить. Я-то почувствовал тепло в груди, увидев слово "пыль".
уже потеряли
Ещё бы и про длину волны что-то.
Цитата: Ly_S от 29 Сен 2014 [18:14:24]Ещё бы и про длину волны что-то.На уровне молекулярно-атомных колебаний, нет?
We describe the theoretical ideas, developed between the 1950s-1970s, which led to the prediction of the Higgs boson, the particle that was discovered in 2012. The forces of nature are based on symmetry principles. We explain the nature of these symmetries through an economic analogy. We also discuss the Higgs mechanism, which is necessary to avoid some of the naive consequences of these symmetries, and to explain various features of elementary particles.
Почти учебник от Хуа́н Марти́н Малдасе́на.
Цитата: Antarctic2054_VimanaProOctoberClone от 27 Окт 2014 [04:41:15]Почти учебник от Хуа́н Марти́н Малдасе́на.Как это читается, с таким ударением?
In cosmological models postulated on the premise of energy-momentum conservation and possibly time-varying global dimensionless quantities, the universe evolves dynamically. The shining example is the standard cosmological model, whose viability rests on a self-consistent retrodiction of several key observational properties, such as the Planckian character of the CMB, early universe nucleosynthesis, etc. In spite of the impressive success of the standard model, key puzzles -- such as the horizon, flatness, and topological defect `problems' -- necessitate the invocation of a brief period of exponential expansion which is presumed to be triggered by a (GUT?) phase transition. Even so, other puzzling features of the standard model remain; chief among these are the nature of dark energy (and its surprisingly low energy density) and of dark matter, and their comparable energy densities at the present epoch. Motivated by the need to resolve these issues, we reformulate general relativity as a conformally invariant scalar-tensor theory with varying G and particle masses; consequently, in a certain gauge the cosmological equations are algebraic rather than differential. We demonstrate the advantages of this theory by a stationary, spatially flat, cosmological model with time-independent angular scales. No flatness and horizon `problems' arise in this model; and therefore no need for an inflationary expansion phase. Dark energy and dark matter are accounted for by ultralight and superheavy scalar fields. Remarkably, energy densities of dark energy (ρDE), dark matter (ρDM), and baryons (ρb), are shown to be related by ρDE=2ρDM+3ρb, in agreement with current observations.
В космологических моделей постулируется на предпосылке сохранения энергии-импульса и, возможно, изменяющихся во времени глобальных безразмерных величин, Вселенная развивается динамично.Ярким примером является стандартная космологическая модель, чья жизнеспособность основывается на самосогласованной retrodiction нескольких ключевых наблюдений свойств, таких как планковской характер реликтового излучения, ранняя Вселенная нуклеосинтеза и т.д. Несмотря на впечатляющие успехи стандартной модели, ключевые головоломки - такие, как горизонт, плоскостности и топологический дефект `проблемы» - необходимость вызов на короткий период экспоненциального расширения, который предположительно быть вызвано фазового перехода (гуд?). Тем не менее, другие загадочные особенности стандартной модели остаются; Главными среди них являются природа темной энергии (и ее удивительно низкой плотностью энергии) и темной материи, и их сопоставимых плотностей энергии в современную эпоху. Руководствуясь необходимостью решить эти вопросы, мы переформулировать ОТО как конформно-инвариантной теории скалярного тензора с различным G и частиц массы; следовательно, в определенной датчика космологические уравнения являются алгебраическими, а не дифференциальными. Мы продемонстрировать преимущества этой теории стационарной пространственно плоской, космологической модели с не зависящими от времени угловых масштабах. Не возникает никаких плоскостности и горизонта `проблемы» в этой модели; и, следовательно, нет необходимости в инфляционной стадии расширения. Темная энергия и темная материя приходится на сверхлегких и сверхтяжелых скалярных полей. Примечательно, что плотность энергии темной энергии (ρDE), темной материи (ρDM), и барионов (ρb), показано, что они связаны ρDE = 2ρDM + 3ρb, в соответствии с текущими наблюдениями.