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David S. Brown’s “In the Arena” is a captivating new biography of Teddy Roosevelt, exploring the life of America’s 26th president and his pivotal role in shaping the dawn of the American Century.
“In the Arena” is more than just an account of a presidency‚ it‚ an exploration of a life lived on the edge of greatness and is a must-read for anyone who wants to better understand this critical period of American history.
General relativity has entered a new phase of its development as technical advances have led to the direct detection of gravitational radiation from the merging of single pairs of stellar-sized black holes.
The exquisite sensitivity of pulsar signal timing measurements has also been exploited to reveal the presence of a background of gravitational waves, most likely arising from the mergers of supermassive black holes thought to be present at the center of most galaxies.
This book demonstrates how general relativity is central to understanding these and other observations.
