Author | Nick Herbert |
---|---|
Cover artist | Mort Weiss, Tita Nasol |
Subject | Quantum physics |
Published | 1985 (Anchor Books/ Doubleday) |
Pages | 268 |
ISBN | 978-0-385-18704-6 |
530.1'2 82-46033 | |
LC Class | QC174.12.H47 1985 |
Quantum Reality is a 1985 popular science book by physicist Nick Herbert, a member of the Fundamental Fysiks Group which was formed to explore the philosophical implications of quantum theory. [1] The book attempts to address the ontology of quantum objects, their attributes, and their interactions, without reliance on advanced mathematical concepts. Herbert discusses the most common interpretations of quantum mechanics and their consequences in turn, highlighting the conceptual advantages and drawbacks of each. [2]
Following a brief summary of the experimental crises (such as the ultraviolet catastrophe) which motivated quantum theory, Herbert identifies four major formulations of quantum theory: Werner Heisenberg's matrix mechanics, Erwin Schrödinger's wave mechanics, Paul Dirac's transformation theory, and Richard Feynman's sum-over-histories formulation. [2]: 41–53
In introducing quantum objects (which he dubs "quons"), Herbert describes how quantum properties inhere in a wave function, which serves as a proxy for the measurement of these properties. He likens the quantum measurement process to mathematically treating the wave function as a summation of waveforms of a particular family, with various families corresponding to particular properties. The bandwidth of the spectrum of these waveforms represents the uncertainty in the quantum measurement. Herbert shows that for pairs of conjugate variables, such as position and momentum, these bandwidths are linked such that their product has a finite lower bound, thereby illustrating the basis of Heisenberg's uncertainty principle: any single property can be measured to arbitrary precision, but conjugate properties cannot simultaneously be known to arbitrary precision. [2]: 71–112
Herbert identifies two philosophical problems presented by quantum theory—the interpretation question, concerning the physical nature of the reality underlying observation; and the measurement problem, concerning the apparently special role of the measurement act in quantum theory, and various approaches to formally defining the measurement act. [2]: 113–156
Herbert identifies eight interpretations of quantum mechanics, all consistent with observation and with the aforementioned mathematical formalisms. He likens these different interpretations to the story of the blind men and an elephant—different approaches to the same underlying reality, which yield remarkably different (but often overlapping) pictures. The interpretations identified by Herbert are:
Adding a further wrinkle to the nature of quantum reality, Herbert presents the EPR paradox, and its resolution in the form of Bell's theorem. The EPR paradox, resting on the long-held assumption of locality, suggests the existence of "elements of reality"—unmeasured quantum attributes which are nonetheless real—which are not predicted by quantum theory. Bell's theorem resolves this paradox by proving that locality is ruled out by observation—that any model of reality consistent with observation must allow for non-local interaction. However, Herbert is careful to note, Bell's theorem does not entail any prediction of experimentally observable non-local phenomena, nor does it allow for superluminal communication. [2]: 211–231
Herbert then re-evaluates the aforementioned interpretations of quantum reality in light of Bell's theorem:
Herbert concludes that, although Bell's theorem does not preclude any of the aforementioned interpretations of quantum mechanics, it insists that any valid interpretation must allow for non-local interaction. [2]: 245
In its review of Quantum Reality, The New York Times praised Herbert's efforts at making the subject matter comprehensible to a lay audience. [3] Physicist Heinz Pagels called Quantum Reality "a great place for the general reader to begin to learn about quantum physics". [4] Kirkus Reviews, however, concluded that Quantum Reality, while engaging, may leave lay readers confused. [5]
Post-anarchist writer Hakim Bey used Quantum Reality as the basis for an analysis of the field of quantum physics in terms of the social paradigms that it may influence, and from which it may draw its metaphors. [6]
Physicist David Kaiser, who has written about the Fundamental Fysiks Group to which Herbert belonged, claims that the book is used in undergraduate physics courses. [1]
Quantum Reality has been translated into German, Japanese, and Portuguese. [7]
Author | Nick Herbert |
---|---|
Cover artist | Mort Weiss, Tita Nasol |
Subject | Quantum physics |
Published | 1985 (Anchor Books/ Doubleday) |
Pages | 268 |
ISBN | 978-0-385-18704-6 |
530.1'2 82-46033 | |
LC Class | QC174.12.H47 1985 |
Quantum Reality is a 1985 popular science book by physicist Nick Herbert, a member of the Fundamental Fysiks Group which was formed to explore the philosophical implications of quantum theory. [1] The book attempts to address the ontology of quantum objects, their attributes, and their interactions, without reliance on advanced mathematical concepts. Herbert discusses the most common interpretations of quantum mechanics and their consequences in turn, highlighting the conceptual advantages and drawbacks of each. [2]
Following a brief summary of the experimental crises (such as the ultraviolet catastrophe) which motivated quantum theory, Herbert identifies four major formulations of quantum theory: Werner Heisenberg's matrix mechanics, Erwin Schrödinger's wave mechanics, Paul Dirac's transformation theory, and Richard Feynman's sum-over-histories formulation. [2]: 41–53
In introducing quantum objects (which he dubs "quons"), Herbert describes how quantum properties inhere in a wave function, which serves as a proxy for the measurement of these properties. He likens the quantum measurement process to mathematically treating the wave function as a summation of waveforms of a particular family, with various families corresponding to particular properties. The bandwidth of the spectrum of these waveforms represents the uncertainty in the quantum measurement. Herbert shows that for pairs of conjugate variables, such as position and momentum, these bandwidths are linked such that their product has a finite lower bound, thereby illustrating the basis of Heisenberg's uncertainty principle: any single property can be measured to arbitrary precision, but conjugate properties cannot simultaneously be known to arbitrary precision. [2]: 71–112
Herbert identifies two philosophical problems presented by quantum theory—the interpretation question, concerning the physical nature of the reality underlying observation; and the measurement problem, concerning the apparently special role of the measurement act in quantum theory, and various approaches to formally defining the measurement act. [2]: 113–156
Herbert identifies eight interpretations of quantum mechanics, all consistent with observation and with the aforementioned mathematical formalisms. He likens these different interpretations to the story of the blind men and an elephant—different approaches to the same underlying reality, which yield remarkably different (but often overlapping) pictures. The interpretations identified by Herbert are:
Adding a further wrinkle to the nature of quantum reality, Herbert presents the EPR paradox, and its resolution in the form of Bell's theorem. The EPR paradox, resting on the long-held assumption of locality, suggests the existence of "elements of reality"—unmeasured quantum attributes which are nonetheless real—which are not predicted by quantum theory. Bell's theorem resolves this paradox by proving that locality is ruled out by observation—that any model of reality consistent with observation must allow for non-local interaction. However, Herbert is careful to note, Bell's theorem does not entail any prediction of experimentally observable non-local phenomena, nor does it allow for superluminal communication. [2]: 211–231
Herbert then re-evaluates the aforementioned interpretations of quantum reality in light of Bell's theorem:
Herbert concludes that, although Bell's theorem does not preclude any of the aforementioned interpretations of quantum mechanics, it insists that any valid interpretation must allow for non-local interaction. [2]: 245
In its review of Quantum Reality, The New York Times praised Herbert's efforts at making the subject matter comprehensible to a lay audience. [3] Physicist Heinz Pagels called Quantum Reality "a great place for the general reader to begin to learn about quantum physics". [4] Kirkus Reviews, however, concluded that Quantum Reality, while engaging, may leave lay readers confused. [5]
Post-anarchist writer Hakim Bey used Quantum Reality as the basis for an analysis of the field of quantum physics in terms of the social paradigms that it may influence, and from which it may draw its metaphors. [6]
Physicist David Kaiser, who has written about the Fundamental Fysiks Group to which Herbert belonged, claims that the book is used in undergraduate physics courses. [1]
Quantum Reality has been translated into German, Japanese, and Portuguese. [7]