To Eliana, who can light up the world with her smile

Published in 2016 by Cavendish Square Publishing, LLC
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Copyright © 2016 by Cavendish Square Publishing, LLC

First Edition

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Library of Congress Cataloging-in-Publication Data

Fields, B. H.

Understanding photons / by B. H. Fields and Fred Bortz.

p. cm. — (Exploring the subatomic world)

Includes index.

ISBN 978-1-50260-544-3 (hardcover) ISBN 978-1-50260-545-0 (ebook)

1. Photons — Juvenile literature. I. Fields, B. H. II. Title.

QC793.5.P42 F48 2016

539.7′217—d23

Editorial Director: David McNamara

Editor: Andrew Coddington

Copy Editor: Cynthia Roby

Art Director: Jeffrey Talbot

Designer: Stephanie Flecha

Senior Production Manager: Jennifer Ryder-Talbot

Production Editor: Renni Johnson

Photo Research: J8 Media

The photographs in this book are used by permission and through the courtesy of: Pictafolio/E+/Getty Images, cover; asharkyu/Shutterstock.com, throughout; Wellcome Images (http://wellcomeimages.org), a website operated by Wellcome Trust, a global charitable foundation based in the United Kingdom/File:Sir Isaac Newton. Wellcome V0006785EL.jpg/Wikimedia Commons, 6; Thomas Forget, 7; Public Domain/ File:Christiaan Huygens, by Caspar Netscher.jpg/Wikimedia Commons, 8; Thomas Forget, 11; Public Domain/File:James Clerk Maxwell profile.jpg/Wikimedia Commons, 12; Jonathan Nackstrand/AFP/ Getty Images, 14; Hulton Archive/Getty Images, 17; Thomas Forget, 19; Public Domain File:Cavendish Experiment.png/Wikimedia Commons, 20; Thomas Forget, 22-23; Johan Hagemeyer, Bancroft Library, University of California Berkeley, courtesy AIP Emilio Segre Visual Archives, 25; Topical Press Agency/ Getty Images, 26; Public Domain/File:Niels Bohr 1935.jpg /Wikimedia Commons, 31; Thomas Forget, 32; Wellcome Images (http://wellcomeimages.org), a website operated by Wellcome Trust, a global charitable foundation based in the United Kingdom/File:Louis Victor Pierre Raymond, Duc de Broglie. Photograph by H Wellcome V0028118.jpg/Wikimedia Commons, 33; W. F. Meggers Collection/AIP Emilio Segre Visual Archives, 34; Robertson. Smithsonian Institution/File:Erwin Schrödinger profile.jpg/Wikimedia Commons, 36; Thomas Forget, 38; Friedrich Hund/File:Heisenberg, Werner 1926.jpeg/Wikimedia Commons, 40; George Frey/Getty Images, 44-45; Forestpath/Shutterstock.com, 47; File:Ernest Rutherford 1905.jpg/Wikimedia Commons, 48; The Air Force Research Laboratory’s Directed Energy Directorate/ File:Lasertests.jpg/Wikimedia Commons, 50; Andrey Bayda/Shutterstock.com, 53.

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