Astronomy

1. Claudia De Rham

The Beauty Of Falling

1. Felix , Würtenberger

Die Welt im freien Fall

Das Buch führt den Leser in 66 kurzen Kapiteln durch das wundersame Land der Kosmologie. Es erzählt von der gekrümmten Raumzeit, Schwarzen Löchern, Dunkler Energie, der Richtung der Zeit und der Unwahrscheinlichkeit unserer Existenz. Anders als die meisten populärwissenschaftlichen Bücher erklärt es interessierten Laien die dahinter liegenden physikalischen Theorien - Formeln inbegriffen! Ausgehend von einfacher Schulmathematik werden Schritt für Schritt alle Grundlagen gelegt, um das Universum in seiner ganzen Schönheit zu verstehen.

1. Scarlett , Alderidge

Silken Shadows of the Serpentine Labyrinth

Prepare to embark on a mind-bending odyssey through the cosmos with Silken Shadows of the Serpentine Labyrinth: An Existentialist Space Opera. Secure your passage to the stars!

1. Mohammad , Enayati
2. Anzhong , Wang
3. Hamed , Pejhan

The de Sitter (dS) Group and Its Representations

This Second Edition is a comprehensive update, integrating the latest research and theoretical advancements in the field of de Sitter (dS) group representations. Building on the success of the first edition, the book offers a more in-depth analysis of mathematical aspects, conceptual foundations, and practical implications related to the dS group, including its Lie manifold, Lie algebra, and co-adjoint orbits, viewing the latter as potential classical elementary systems within the context of dS spacetime. Additionally, the examination of unitary irreducible representations (UIRs) sheds light on the potential existence of quantum elementary systems within the dS spacetime framework. The authors emphasize consistency with Wigner's approach to elementary systems, incorporate Wigner's principles and exploring projective UIRs of the dS group, and provide a deeper insight into the nature of dS elementary systems. Particular attention is paid to: the ¿smooth¿ transition from classical to quantum theory, the physical content under vanishing curvature, and the thermal interpretation from a quantum perspective. The book also focuses on the physical interpretation of elementary systems in curved spacetimes, recognizing the limitations of traditional concepts derived from flat Minkowski spacetime and the Poincaré group.

1. Mohammad , Enayati
2. Anzhong , Wang
3. Hamed , Pejhan

The de Sitter (dS) Group and its Representations

This book reviews the construction of elementary systems living in de Sitter (dS) spacetime, in both the classical and quantum senses. Field theories on dS spacetime are among the most studied mathematical models of the Universe, whether for its earlier period (inflationary phase) or for its current phase of expansion acceleration (dark energy or cosmological constant). Classical elementary systems are Hamiltonian phase spaces, which are associated with co-adjoint orbits of the relativity group. On the other hand, quantum elementary systems are associated with (projective) unitary irreducible representations of the (possibly extended) relativity group (or one of its covering). This study emphasizes the conceptual issues arising in the formulation of such systems and discusses known results in a mathematically rigorous way. Particular attention is paid to: ¿smooth¿ transition from classical to quantum theory; physical content under vanishing curvature, from the point of view of a local(¿tangent¿) Minkowskian observer; and thermal interpretation (on the quantum level), in the sense of the Gibbons-Hawking temperature. Such a mathematical construction is of paramount importance to the understanding of the early Universe (due to the critical role that the dS metric plays in the inflationary cosmological scenarii) as well as to the construction of possible models for late-time cosmology (since a small positive cosmological constant or dark energy seems to be required by recent data). In this sense, this book uniquely blends mathematical physics (spacetime symmetry on classical and quantum levels) and theoretical physics (quantization, quantum field theory, and cosmology). Moreover, the level of exposition varies in different parts of the book so that both experts and beginners alike can utilize the book.

1. Alessandro , De Angelis

Cosmic Rays

In recent years, cosmic rays have become the protagonists of a new scientific revolution. We are able today to film the Universe with telescopes of completely novel conception, recording information from many different messengers and accessing previously unknown cosmic regions.Written by a recognized authority in physics, this book takes readers on a captivating journey through the world of cosmic rays, their role in the revolutionary field of multi-messenger astronomy, their production from powerful accelerators close to the surfaces of black holes and compact objects, reaching the highest levels of energy observed in nature, and the implications this has for our understanding of the Universe. Through the stories of pioneering scientists, explorations of cutting-edge technologies, and simple explanations related to particle physics, quantum mechanics, and astrophysics, the book provides an illuminating state-of-the-art introduction to the current state of high-energy astrophysics. The book was written in straightforward yet rigorous language, so as to be accessible to the greater public. For those curious about the cosmos and cosmic gamma rays, nuclei, neutrinos, and gravitational waves, from casual observers to professional astronomers and physicists, the book is a must-read, offering a thrilling adventure into the future of astronomy and particle physics.