Arnab Rai Choudhuri – författare

The cycle of day and night and the cycle of seasons are two familiar natural cycles around which many human activities are organized. But is there a third natural cycle of importance for us humans? On 13 March 1989, six million people in Canada went without electricity for many hours: a large explosion on the sun was discovered as the cause of this blackout. Such explosions occur above sunspots, dark features on the surface of the Sun that have been observed through telescopes since the time of Galileo.The number of sunspots has been found to wax and wane over a period of 11 years. Although this cycle was discovered less than two centuries ago, it is becoming increasingly important for us as human society becomes more dependent on technology. For nearly a century after its discovery, the cause of the sunspot cycle remained completely shrouded in mystery. The 1908 discovery of strong magnetic fields in sunspots made it clear that the 11-year cycle is the magnetic cycle of the sun. It is only during the last few decades that major developments in plasma physics have at last given us the clue to the origins of the cycle and how the large explosions affecting the earth arise.Nature's Third Cycle discusses the fascinating science behind the sunspot cycle, and gives an insider's perspective of this cutting-edge scientific research from one of the leaders of the field.

The cycle of day and night and the cycle of seasons are two familiar natural cycles around which many human activities are organized. But is there a third natural cycle of importance for us humans? On 13 March 1989, six million people in Canada went without electricity for many hours: a large explosion on the sun was discovered as the cause of this blackout. Such explosions occur above sunspots, dark features on the surface of the Sun that have been observed through telescopes since the time of Galileo. The number of sunspots has been found to wax and wane over a period of 11 years. Although this cycle was discovered less than two centuries ago, it is becoming increasingly important for us as human society becomes more dependent on technology. For nearly a century after its discovery, the cause of the sunspot cycle remained completely shrouded in mystery. The 1908 discovery of strong magnetic fields in sunspots made it clear that the 11-year cycle is the magnetic cycle of the sun. It is only during the last few decades that major developments in plasma physics have at last given us the clue to the origins of the cycle and how the large explosions affecting the earth arise.Nature's Third Cycle discusses the fascinating science behind the sunspot cycle, and gives an insider's perspective of this cutting-edge scientific research from one of the leaders of the field.

A good working knowledge of fluid mechanics and plasma physics is essential for the modern astrophysicist. This graduate textbook provides a clear, pedagogical introduction to these core subjects. Assuming an undergraduate background in physics, this book develops fluid mechanics and plasma physics from first principles. This book is unique because it presents neutral fluids and plasmas in a unified scheme, clearly indicating both their similarities and their differences. Also, both the macroscopic (continuum) and microscopic (particle) theories are developed, establishing the connections between them. Throughout, key examples from astrophysics are used, though no previous knowledge of astronomy is assumed. Exercises are included at the end of chapters to test the reader's understanding. This textbook is aimed primarily at astrophysics graduate students. It will also be of interest to advanced students in physics and applied mathematics seeking a unified view of fluid mechanics and plasma physics, encompassing both the microscopic and macroscopic theories.

Designed for teaching astrophysics to physics students at advanced undergraduate or beginning graduate level, this textbook also provides an overview of astrophysics for astrophysics graduate students, before they delve into more specialized volumes. Assuming background knowledge at the level of a physics major, the textbook develops astrophysics from the basics without requiring any previous study in astronomy or astrophysics. Physical concepts, mathematical derivations and observational data are combined in a balanced way to provide a unified treatment. Topics such as general relativity and plasma physics, which are not usually covered in physics courses but used extensively in astrophysics, are developed from first principles. While the emphasis is on developing the fundamentals thoroughly, recent important discoveries are highlighted at every stage.

This textbook provides a comprehensive one-semester course on advanced electromagnetic theory written from the modern perspective covering all important topics that a professional physicist needs to know.