Itihas Kaal Aur Adikalin Bharat

In this book, Romila Thapar examines the link between time and history through the use of cyclic and linear concepts of time. While the former occurs in a cosmological context, the latter is found in familiar historical forms. The author argues for the existence of historical consciousness in early India, on the evidence of early texts. This is the Hindi edition translated from English.

In this book, Romila Thapar examines the link between time and history through the use of cyclic and linear concepts of time. While the former occurs in a cosmological context, the latter is found in familiar historical forms. The author argues for the existence of historical consciousness in early India, on the evidence of early texts. This is the Hindi edition translated from English.

Ancient Indian history has always been mystical; more so a virtual utopia for historians and researchers. This scholarly text narrates the ancient Indian history from the genesis of civilisations to the early middle ages. It examines the sources, chronology of civilisations and authoritatively details the facts, feats, triumphs and religious crusades of the period. It unveils the rich cultural, religious and social diversity that is uniquely and peculiarly Indian. The book is of immense use to students and scholars of history and for candidates preparing for civil services examinations.

This graduate textbook on optimal spacecraft trajectories demonstrates the theory and applications of using the minimum amount of propellant possible to reach a target destination. The author aims to produce the only comprehensive treatment of various aspects of this topic. It includes problems at the ends of the chapters and some of the appendices. But it is also suitable as a scholarly reference book as it includes recent research from the author and his colleagues.

Illustrated with breathtaking images of the Solar System and of the Universe around it, this book explores how the discoveries within the Solar System and of exoplanets far beyond it come together to help us understand the habitability of Earth, and how these findings guide the search for exoplanets that could support life. The author highlights how, within two decades of the discovery of the first planets outside the Solar System in the 1990s, scientists concluded that planets are so common that most stars are orbited by them. The lives of exoplanets and their stars, as of our Solar System and its Sun, are inextricably interwoven. Stars are the seeds around which planets form, and they provide light and warmth for as long as they shine. At the end of their lives, stars expel massive amounts of newly forged elements into deep space, and that ejected material is incorporated into subsequent generations of planets. How do we learn about these distant worlds? What does the exploration of other planets tell us about Earth? Can we find out what the distant future may have in store for us? What do we know about exoworlds and starbirth, and where do migrating hot Jupiters, polluted white dwarfs, and free-roaming nomad planets fit in? And what does all that have to do with the habitability of Earth, the possibility of finding extraterrestrial life, and the operation of the globe-spanning network of the sciences?

The Les Houches Summer School in August 2015 covered the emerging fields of cavity optomechanics and quantum nanomechanics. Optomechanics is flourishing and its concepts and techniques are now applied to a wide range of topics. Modern quantum optomechanics was born in the late 1970s in the framework of gravitational wave interferometry, with an initial focus on the quantum limits of displacement measurements. Carlton Caves, Vladimir Braginsky, and others realized that the sensitivity of the anticipated large-scale gravitational-wave interferometers (GWI) was fundamentally limited by the quantum fluctuations of the measurement laser beam. After tremendous experimental progress, the sensitivity of the upcoming next generation of GWI will effectively be limited by quantum noise. In this way, quantum-optomechanical effects will directly affect the operation of what is arguably the world's most impressive precision experiment. However, optomechanics has also gained a life of its own with a focus on the quantum aspects of moving mirrors. Laser light can be used to cool mechanical resonators well below the temperature of its environment. After proof-of-principle demonstrations of this cooling in 2006, a number of systems were used as the field gradually merged with its condensed matter cousin (nanomechanical systems) to try to reach the mechanical quantum ground state, eventually demonstrated in 2010 by pure cryogenic techniques and just one year later by a combination of cryogenic and radiation-pressure cooling. The book covers all aspects -- historical, theoretical, experimental -- of the field, with its applications to quantum measurement, foundations of quantum mechanics and quantum information. It is an essential read for any new researcher in the field.