Scientific American / Farrar, Straus and Giroux

18 West 18th Street, New York 10011

Copyright © 2012 by Caleb Scharf

All rights reserved

First edition, 2012

A portion of chapter 8 originally appeared, in slightly different form, in Scientific American.

Library of Congress Cataloging-in-Publication Data

Scharf, Caleb A., 1968–

   Gravity’s engines : how bubble-blowing black holes rule galaxies, stars, and life in the cosmos / Caleb Scharf.

       p. cm.

   Includes index.

   ISBN 978-0-374-11412-1 (hardback)

   1.  Black holes (Astronomy)   2.  Gravity.   3.  Cosmology.   I.  Title.

QB843.B55 S33 2012

523.8'875—dc23

2011047089

eISBN 9780374709754

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