The Fabric of the Cosmos
Encyclopedia
The Fabric of the Cosmos: Space, Time, and the Texture of Reality (2004) is the second book on theoretical physics
Theoretical physics
Theoretical physics is a branch of physics which employs mathematical models and abstractions of physics to rationalize, explain and predict natural phenomena...

, cosmology
Physical cosmology
Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of the universe and is concerned with fundamental questions about its formation and evolution. For most of human history, it was a branch of metaphysics and religion...

, and string theory
String theory
String theory is an active research framework in particle physics that attempts to reconcile quantum mechanics and general relativity. It is a contender for a theory of everything , a manner of describing the known fundamental forces and matter in a mathematically complete system...

 written by Brian Greene
Brian Greene
Brian Greene is an American theoretical physicist and string theorist. He has been a professor at Columbia University since 1996. Greene has worked on mirror symmetry, relating two different Calabi-Yau manifolds...

, professor and co-director of Columbia's
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...

 Institute for Strings, Cosmology, and Astroparticle Physics (ISCAP).

Introduction

Greene begins with the key question: What is reality
Reality
In philosophy, reality is the state of things as they actually exist, rather than as they may appear or might be imagined. In a wider definition, reality includes everything that is and has been, whether or not it is observable or comprehensible...

? Or more specifically: What is spacetime
Spacetime
In physics, spacetime is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as being three-dimensional and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions...

? He sets out to describe the features he finds both exciting and essential to forming a full picture of the reality painted by modern science
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

. In almost every chapter, Greene introduces its basic concepts and then slowly builds to a climax, which is usually a scientific breakthrough. Greene then attempts to connect with his reader by posing simple analogies to help explain the meaning of a scientific concept without oversimplifying the theory behind it.

In the preface, Greene acknowledges that some parts of the book are controversial among scientists. Greene discusses the leading viewpoints in the main text, and points of contention in the end notes. Greene has striven for balanced treatment of the controversial topics. In the end notes, the diligent reader will find more complete explanations relevant to points he has simplified in the main text.

Part 1: Reality's Arena

The main focus of part one is space
Space
Space is the boundless, three-dimensional extent in which objects and events occur and have relative position and direction. Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, with time, to be part of a boundless four-dimensional continuum...

 and time
Time
Time is a part of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify rates of change such as the motions of objects....

.

Chapter one is an introduction of what is to come later in the book, such as discussions revolving around classical physics
Classical physics
What "classical physics" refers to depends on the context. When discussing special relativity, it refers to the Newtonian physics which preceded relativity, i.e. the branches of physics based on principles developed before the rise of relativity and quantum mechanics...

, quantum mechanics
Quantum mechanics
Quantum mechanics, also known as quantum physics or quantum theory, is a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. It departs from classical mechanics primarily at the atomic and subatomic...

 and cosmological
Physical cosmology
Physical cosmology, as a branch of astronomy, is the study of the largest-scale structures and dynamics of the universe and is concerned with fundamental questions about its formation and evolution. For most of human history, it was a branch of metaphysics and religion...

 physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...

.

The second chapter, The Universe and the Bucket, features space as its key point. The question posed by Greene is this: "Is space a human abstraction, or is it a physical entity?" The key thought experiment
Thought experiment
A thought experiment or Gedankenexperiment considers some hypothesis, theory, or principle for the purpose of thinking through its consequences...

 is a spinning bucket of water
Bucket argument
Isaac Newton's rotating bucket argument was designed to demonstrate that true rotational motion cannot be defined as the relative rotation of the body with respect to the immediately surrounding bodies...

, designed to make one think about what creates the force felt inside the bucket when it is spinning. The ideas of Isaac Newton
Isaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...

, Ernst Mach
Ernst Mach
Ernst Mach was an Austrian physicist and philosopher, noted for his contributions to physics such as the Mach number and the study of shock waves...

, and Gottfried Leibniz
Gottfried Leibniz
Gottfried Wilhelm Leibniz was a German philosopher and mathematician. He wrote in different languages, primarily in Latin , French and German ....

 on this thought experiment are discussed in detail.

Chapter three, Relativity and the Absolute, makes spacetime
Spacetime
In physics, spacetime is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as being three-dimensional and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions...

 its focal point. The question now becomes, "Is spacetime an Einsteinian abstraction or a physical entity?" In this chapter, concepts of both special relativity
Special relativity
Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's...

 and general relativity
General relativity
General relativity or the general theory of relativity is the geometric theory of gravitation published by Albert Einstein in 1916. It is the current description of gravitation in modern physics...

 are discussed as well as their importance to the meaning of spacetime.

In chapter four, Entangling Space, Greene explores the revolution of the quantum mechanical era, focusing on what it means for objects to be separate and distinct in a universe dictated by quantum laws. This chapter provides an in-depth study of quantum mechanics, including the concepts of probability waves and interference patterns, particle spin
Spin (physics)
In quantum mechanics and particle physics, spin is a fundamental characteristic property of elementary particles, composite particles , and atomic nuclei.It is worth noting that the intrinsic property of subatomic particles called spin and discussed in this article, is related in some small ways,...

, the photon double slit experiment, and Heisenberg's uncertainty principle. The reader will also be informed of the challenges posed to quantum mechanics that were compiled by Albert Einstein
Albert Einstein
Albert Einstein was a German-born theoretical physicist who developed the theory of general relativity, effecting a revolution in physics. For this achievement, Einstein is often regarded as the father of modern physics and one of the most prolific intellects in human history...

, Boris Podolsky
Boris Podolsky
Boris Yakovlevich Podolsky , was an American physicist of Russian Jewish descent.-Education:In 1896, Boris Podolsky was born into a poor Jewish family in Taganrog, in what was then the Russian Empire, and he moved to the United States in 1913...

, and Nathan Rosen
Nathan Rosen
Nathan Rosen was an American-Israeli physicist noted for his study on the structure of the hydrogen molecule and his work with Albert Einstein and Boris Podolsky on entangled wave functions and the EPR paradox.-Background:Nathan Rosen was born into a Jewish family in Brooklyn, New York...

.

Part 2: Time and Experience

Part two begins by addressing the issue that time is a very familiar concept, yet it is one of humanity
Human Race
Human Race refers to the Human species.Human race may also refer to:*The Human Race, 79th episode of YuYu Hakusho* Human Race Theatre Company of Dayton Ohio* Human Race Machine, a computer graphics device...

's least understood concepts.

Chapter five, The Frozen River, deals with the question, "Does time flow?" One of the key points in this chapter deals with special relativity. Observers moving relative to each other have different conceptions of what exists at a given moment, and hence they have different conceptions of reality. The conclusion is that time does not flow, as all things simultaneously exist at the same time.

Chapter six, Chance and the Arrow, asks the question, "Does time have an arrow
Arrow of time
The arrow of time, or time’s arrow, is a term coined in 1927 by the British astronomer Arthur Eddington to describe the "one-way direction" or "asymmetry" of time...

?" The reader learns that the laws of physics apply both moving forward in time and backwards in time. Such a law is called time-reversal symmetry
T-symmetry
T Symmetry is the symmetry of physical laws under a time reversal transformation: T: t \mapsto -t.Although in restricted contexts one may find this symmetry, the observable universe itself does not show symmetry under time reversal, primarily due to the second law of thermodynamics.Time asymmetries...

. One of the major subjects of this chapter is entropy
Entropy
Entropy is a thermodynamic property that can be used to determine the energy available for useful work in a thermodynamic process, such as in energy conversion devices, engines, or machines. Such devices can only be driven by convertible energy, and have a theoretical maximum efficiency when...

. Various analogies are given to illustrate how entropy works and its apparent paradoxes. The climax of the chapter is the co-relation between entropy and gravity, and that the beginning of the universe must be the state of minimum entropy
Absolute zero
Absolute zero is the theoretical temperature at which entropy reaches its minimum value. The laws of thermodynamics state that absolute zero cannot be reached using only thermodynamic means....

.

In chapters five and six, time has been explained only in terms of pre-modern physics. Chapter seven, Time and the Quantum, gives insights into time's nature in the quantum realm
Quantum realm
Quantum realm is a term of art in physics referring to scales where quantum mechanical effects become important . Typically, this means distances of 100 nanometers or less. Not coincidentally, this is the same scale as nanotechnology....

. Probability plays a major role in this chapter because it is an inescapable part of quantum mechanics. The double slit experiment is revisited in a stunning way that reveals both interesting and shocking things about the past. Many other experiments are presented in this chapter, such as the delayed choice quantum eraser experiment
Quantum eraser experiment
In quantum mechanics, the quantum eraser experiment is a double-slit experiment that demonstrates several fundamental aspects of the quantum theory, including quantum entanglement and complementarity....

. Other major issues are brought to the reader's attention, such as quantum mechanics and experience, as well as quantum mechanics and the measurement problem
Measurement problem
The measurement problem in quantum mechanics is the unresolved problem of how wavefunction collapse occurs. The inability to observe this process directly has given rise to different interpretations of quantum mechanics, and poses a key set of questions that each interpretation must answer...

. Finally, this chapter thoroughly addresses the important subject of decoherence and its relevance towards the macroscopic
Macroscopic
The macroscopic scale is the length scale on which objects or processes are of a size which is measurable and observable by the naked eye.When applied to phenomena and abstract objects, the macroscopic scale describes existence in the world as we perceive it, often in contrast to experiences or...

 world.

Part 3: Spacetime and Cosmology

Part three deals with the macroscopic realm of the cosmos
Cosmos
In the general sense, a cosmos is an orderly or harmonious system. It originates from the Greek term κόσμος , meaning "order" or "ornament" and is antithetical to the concept of chaos. Today, the word is generally used as a synonym of the word Universe . The word cosmos originates from the same root...

.

Chapter eight, Of Snowflakes and Spacetime, tells the reader that the history of the universe is in fact the history of symmetry
Symmetry
Symmetry generally conveys two primary meanings. The first is an imprecise sense of harmonious or aesthetically pleasing proportionality and balance; such that it reflects beauty or perfection...

. Symmetry and its importance to cosmic evolution becomes the focus of this chapter. Again, general relativity is addressed as a stretching fabric of spacetime. Cosmology, symmetry, and the shape of space are put together in a unique way.

Chapter nine, Vaporizing the Vacuum
, introduces the theoretical idea of the Higgs boson
Higgs boson
The Higgs boson is a hypothetical massive elementary particle that is predicted to exist by the Standard Model of particle physics. Its existence is postulated as a means of resolving inconsistencies in the Standard Model...

. This chapter focuses on the critical first fraction of a second after the big bang
Big Bang
The Big Bang theory is the prevailing cosmological model that explains the early development of the Universe. According to the Big Bang theory, the Universe was once in an extremely hot and dense state which expanded rapidly. This rapid expansion caused the young Universe to cool and resulted in...

, when the amount of symmetry in the universe was thought to have changed abruptly by a process known as symmetry breaking
Symmetry breaking
Symmetry breaking in physics describes a phenomenon where small fluctuations acting on a system which is crossing a critical point decide the system's fate, by determining which branch of a bifurcation is taken. To an outside observer unaware of the fluctuations , the choice will appear arbitrary...

. This chapter also brings into play the theory of grand unification and entropy is also revisited.

Chapter ten, Deconstructing the Bang, makes inflationary cosmology the main point. General relativity and the discovery of dark energy
Dark energy
In physical cosmology, astronomy and celestial mechanics, dark energy is a hypothetical form of energy that permeates all of space and tends to accelerate the expansion of the universe. Dark energy is the most accepted theory to explain recent observations that the universe appears to be expanding...

 (repulsive gravity) are taken into account, as well as the cosmological constant
Cosmological constant
In physical cosmology, the cosmological constant was proposed by Albert Einstein as a modification of his original theory of general relativity to achieve a stationary universe...

. Certain problems that arise due to the standard big bang theory are addressed and new answers are given using inflationary cosmology. Such problems include the horizon problem
Horizon problem
The horizon problem is a problem with the standard cosmological model of the Big Bang which was identified in the 1970s. It points out that different regions of the universe have not "contacted" each other because of the great distances between them, but nevertheless they have the same temperature...

 and the flatness problem. Matter distribution throughout the cosmos is also discussed, and the concepts of dark matter
Dark matter
In astronomy and cosmology, dark matter is matter that neither emits nor scatters light or other electromagnetic radiation, and so cannot be directly detected via optical or radio astronomy...

 and dark energy come full circle.

Chapter eleven, Quanta in the Sky with Diamonds, continues with the topic of inflation, and the arrow of time is also discussed again. The chapter addresses three main developments, the formation of structures such as galaxies, the amount of energy required to spawn the universe we now see, and, of prime importance, the origin of time's arrow.

Part 4: Origins and Unification

Part four deals with new theoretical aspects of physics, particularly in the field of the author.

Chapter twelve, The World on a String, informs the reader of the structure of the fabric of space according to string theory
String theory
String theory is an active research framework in particle physics that attempts to reconcile quantum mechanics and general relativity. It is a contender for a theory of everything , a manner of describing the known fundamental forces and matter in a mathematically complete system...

. New concepts are introduced, including the Planck length and the Planck time
Planck time
In physics, the Planck time, , is the unit of time in the system of natural units known as Planck units. It is the time required for light to travel, in a vacuum, a distance of 1 Planck length...

, and ideas from
The Elegant Universe
The Elegant Universe
The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory is a book by Brian Greene published in 1999, which introduces string and superstring theory, and provides a comprehensive though non-technical assessment of the theory and some of its shortcomings...

are revisited. The reader will learn how string theory fills the gaps between general relativity and quantum mechanics.

Chapter thirteen,
The Universe on a Brane, expands on ideas from chapter twelve, particularly, a theory called M-theory
M-theory
In theoretical physics, M-theory is an extension of string theory in which 11 dimensions are identified. Because the dimensionality exceeds that of superstring theories in 10 dimensions, proponents believe that the 11-dimensional theory unites all five string theories...

, of which string theory is a branch. This chapter is devoted to speculations on space and time according to M-theory. The collective insights of a number of physicists are presented, including those of Edward Witten
Edward Witten
Edward Witten is an American theoretical physicist with a focus on mathematical physics who is currently a professor of Mathematical Physics at the Institute for Advanced Study....

 and Paul Dirac
Paul Dirac
Paul Adrien Maurice Dirac, OM, FRS was an English theoretical physicist who made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics...

. The focal point of the chapter becomes gravity and its involvement with extra dimensions. Near the end of the chapter, a brief section is devoted to cyclic cosmology, otherwise known as the cyclic model
Cyclic model
A cyclic model is any of several cosmological models in which the universe follows infinite, self-sustaining cycles. For example, the oscillating universe theory briefly considered by Albert Einstein in 1930 theorized a universe following an eternal series of oscillations, each beginning with a...

.

Part 5: Reality and Imagination

Part five deals with many theoretical concepts, including space and time travel
Time travel
Time travel is the concept of moving between different points in time in a manner analogous to moving between different points in space. Time travel could hypothetically involve moving backward in time to a moment earlier than the starting point, or forward to the future of that point without the...

.

Chapter fourteen, Up in the Heavens and Down on the Earth, is about various experiments with space and time. Previous theories are brought back from previous chapters, such as Higgs theory, supersymmetry
Supersymmetry
In particle physics, supersymmetry is a symmetry that relates elementary particles of one spin to other particles that differ by half a unit of spin and are known as superpartners...

, and string theory. Future planned experiments are described in an attempt to verify many of the theoretical concepts discussed, including the constituents of dark matter and dark energy, the existence of the Higgs boson, and the verification of extra spacial dimensions.

Chapter fifteen, Teleporters and Time Machines, is about travelling through space and time using intriguing methods. Quantum mechanics is brought back into the picture when the reader comes across teleportation
Quantum teleportation
Quantum teleportation, or entanglement-assisted teleportation, is a process by which a qubit can be transmitted exactly from one location to another, without the qubit being transmitted through the intervening space...

. Puzzles of time travel are posed, such as the idea of time travel to the past being a possibility. The end of the chapter focuses on worm holes and the theory behind them.

Chapter sixteen, The Future of an Allusion, focuses on black hole
Black hole
A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that...

s and their relationship to entropy. The main idea of this chapter is that spacetime may not be the fundamental make up of the universe's fabric.

Reception

The Fabric of the Cosmos became the most popular science book among Amazon.com
Amazon.com
Amazon.com, Inc. is a multinational electronic commerce company headquartered in Seattle, Washington, United States. It is the world's largest online retailer. Amazon has separate websites for the following countries: United States, Canada, United Kingdom, Germany, France, Italy, Spain, Japan, and...

 customers in 2005 and was on the New York Times bestseller list - from its publication on February 10, 2004 it appeared 10 times in the Non-Fiction top 15, peaking at number 3 on April 4th, before dropping off the list on May 9. With a first printing of 125,000 and as a main selection of the Book of the Month Club
Book of the Month Club
The Book of the Month Club is a United States mail-order book sales club that offers a new book each month to customers.The Book of the Month Club is part of a larger company that runs many book clubs in the United States and Canada. It was formerly the flagship club of Book-of-the-Month Club, Inc...

, Knopf expected it to do well.
It currently (October 2011) has an average reviewer rating of 4½ stars (out of 5), with 175 out of the 254 reviewers having given it 5 stars.

Adaptation

NOVA
NOVA (TV series)
Nova is a popular science television series from the U.S. produced by WGBH Boston. It can be seen on the Public Broadcasting Service in the United States, and in more than 100 other countries...

 has made a sequel to the popular Elegant Universe adaptation based on The Fabric of the Cosmos and retaining the same name.

Publication data

  • The Fabric of the Cosmos: Space, Time, and the Texture of Reality (2004). Alfred A. Knopf
    Alfred A. Knopf
    Alfred A. Knopf, Inc. is a New York publishing house, founded by Alfred A. Knopf, Sr. in 1915. It was acquired by Random House in 1960 and is now part of the Knopf Doubleday Publishing Group at Random House. The publishing house is known for its borzoi trademark , which was designed by co-founder...

     division, Random House
    Random House
    Random House, Inc. is the largest general-interest trade book publisher in the world. It has been owned since 1998 by the German private media corporation Bertelsmann and has become the umbrella brand for Bertelsmann book publishing. Random House also has a movie production arm, Random House Films,...

    , ISBN 0-375-41288-3

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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