Die vorliegende Schrift behandelt die Kalenderlehre unter bewuBter Ausscheidung aller historischen Betrachtungen. Liegt darin einerseits e: ne Beschrankung, so glaubt der Ver fasser andererseits durch die Loslosung von der vielverschlungenen und daher mit mancherlei Ballast behafteten Entwickelungs geschichte des Kalenderwesens dessen mathematischen Kern sozusagen reinlicher herausschalen zu konnen, als es bei einer historischen Darstellung moglich ware. Die Schrift wendet sich an einen sehr allgemeinen Leser kreis. Sie mochte jedem Gebildeten zuganglich sein, der mathe matischen Oberlegungen einfachster Art Interesse entgegen bringt. Da und dort mag vieHeicht der Historiker bei chrono logischen Untersuchungen aus ihr Nutzen ziehen konnen. Eine besondere Freude ware es dem V erfasser, wenn zuweilen ein Feldgrauer nach dem Schriftchen griffe; weiB er doch aus eigener Erfahrung, wie es Zeiten gibt, in denen der Soldat nach irgendwelcher geistigen Anregung hungert - ganz ab gesehen davon, daB es im Felde von praktischem Interesse sein kann, nach kurzer Dberlegung zu wissen, welche Mondphase einem gegebenen Datum zukommt. Aber dariiber hinaus mochte das Biichlein auch dem an gehenden Mathematiker etwas zu sagen haben, und vor aHem dem Unterricht an hoheren Schulen dienen. Sollte die Schrift einem so verschiedenartigen Leserkreise gerecht werden, so war dies nur moglich durch eine besondere Behandlungsweise des Stoffes: die Darstellung zerfallt gewisser maBen in mehrere "Kreise," deren jeder in sich geschlossen und verstandlich ist. Der engste erfordert kaum mehr, als die Kennt nis der vier Grundrechnungsarten. Der nachste setzt schon Vorwort."

Unlike many textbooks or popular science books, A Simple Guide to Popular Physics has truly been crafted for the uninitiated or those spooked by the subject's complexity. Harris's inviting guide promises to give "absolute beginners" from "teens to centenarians" a basic grounding in particle physics, quantum physics, and cosmology-all without making readers do math. With the goal of introducing the basics and encouraging readers to explore more deeply afterwards, Harris notes "Like the fish we have no notion of what is beyond the boundaries of our knowledge, but unlike the fish, we know there is something." He starts by presenting those boundaries, the fundamentals of classic physics (Newton's law, states of matter, types of energy), with crisp clarity before laying out an accessible explanation of Einstein's theory of relativity, the structure of the atom, the mysteries of quantum mechanics and cosmology. Readers will not need to search online for key terms or explanations of concepts that have been glossed over. Instead, one by one, with patience and good humor, Harris introduces each of these building blocks of our universe, taking a little time to invite readers to contemplate the momentousness of the information, as in the chapter titled nothing less than "What Is Reality?" The watchword, here, is clarity, which Harris offers throughout, with professional illustrations and illuminating accounts of experiments and breakthroughs, offering a solid foundation for understanding and future reading.

If you move at high speed, time slows down, space squashes up and you get heavier. Travel fast enough and you could weigh as much as a jumbo jet, be flattened thinner than a CD without feeling a thing-and live forever As for the angles of a triangle, they do not always have to add up to 180 degrees. And then, of course, there are black holes. These are but a few of the extraordinary consequences of Einstein's theory of relativity. It is now over a hundred years since he made these discoveries, and yet the general public is still largely unaware of them. Filled with illuminating anecdotes and fascinating accounts of experiments, this book aims to introduce the interested lay person to the subject of relativity in a way which is accessible and engaging and at the same time scientifically rigorous. With relatively few mathematical equations--nothing more complicated than the Pythagoras's Theorem--this VSI packs a lot time into very little space, and for anyone who has felt intimidated by Einstein's groundbreaking theory, it offers the perfect place to start.
About the Series: Combining authority with wit, accessibility, and style, Very Short Introductions offer an introduction to some of life's most interesting topics. Written by experts for the newcomer, they demonstrate the finest contemporary thinking about the central problems and issues in hundreds of key topics, from philosophy to Freud, quantum theory to Islam.