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The nature of light: what is a photon?

Chandrasekhar Roychoudhuri, Kracklauer, AF, Creath, Kathy

Published Jan 1, 2008• 82 citations
OpenAlex

Abstract

Focusing on the unresolved debate between Newton and Huygens from 300 years ago, The Nature of Light: What is a Photon? discusses the reality behind enigmatic photons. It explores the fundamental issues pertaining to light that still exist today. Gathering contributions from globally recognized specialists in electrodynamics and quantum optics, the book begins by clearly presenting the mainstream view of the nature of light and photons. It then provides a new and challenging scientific epistemology that explains how to overcome the prevailing paradoxes and confusions arising from the accepted definition of a photon as a monochromatic Fourier mode of the vacuum. The book concludes with an array of experiments that demonstrate the innovative thinking needed to examine the wave-particle duality of photons. Looking at photons from both mainstream and out-of-box viewpoints, this volume is sure to inspire the next generation of quantum optics scientists and engineers to go beyond the Copenhagen interpretation and formulate new conceptual ideas about light-matter interactions and substantiate them through inventive applications.

Related papers

What is light?

Have you ever tried to define light? If so, your definition is probably related to vision, the ability to see things. The Merriam-Webster English dictionary defines light as “something that makes vision possible”. However, the definition of the “nature of light” is a complex term already discussed by philosophers of Ancient Greece. In the 17th century, the debate on the matter focused on whether light was a particle or a wave, based on the different properties of light that had been gradually discovered over time. Isaac Newton (1642−1727) was a defender of the corpuscular theory of light, which considered light to be formed by particles, i.e., small pieces of matter, like dust or grains of sand. He was the author of Opticks (1706), the front cover of which appears in Fig. 1.1. Christian Huygens (1629–1695), on the other hand, supported the theory that light is a wave. These are two completely different definitions of the same physical concept. A range of experiments were developed to attempt to clarify this dilemma, but it was only until 1900 when Max Planck (1858-1947) introduced the basis of a theory that would go on to revolutionize scientific thinking, marking the beginning of modern physics: quantum theory. Developed during the 20th century thanks to advances made by scientists such as Niels Bohr, Born, Heisenberg, Schrödinger, Pauli, Dirac, Einstein or de Broglie, quantum theory clarified that light is neither a particle nor a wave, but that it has a dual nature: it behaves like a wave as it spreads but like a particle in its interactions with matter. In this book, we will specify where necessary whether light behaves as a particle or as a wave, although in most cases we refer to rays of light, which always represent the direction of propagation of light.

SPIE eBooks•May 6, 2021•0 citations

The Concept of the Photon—Revisited

Ashok Muthukrishnan, Marlan O. Scully, Muhammad Suhail Zubairy

concept is one of the most debated issues in the history of physical science. Some thirty years ago, we published an article in Physics Today entitled The Concept of the Photon, 1 in which we described the photon as a classical electromagnetic field plus the fluctuations associated with the vacuum. However, subsequent developments required us to envision the as an intrinsically quantum mechanical entity, whose basic physics is much deeper than can be explained by the simple 'classical wave plus vacuum fluctuations' picture. These ideas and the extensions of our conceptual understanding are discussed in detail in our recent quantum optics book. 2 In this article we revisit the concept based on examples from these sources and more.

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Fundamentals of Photon Physics

Ole Keller

The photon, an abstract concept belonging to a global vacuum, only manifests itself during interaction with matter. Fundamentals of Photon Physics describes the richly faceted, basic theory of photon-matter interaction, selecting a wide number of topics. Together with the author’s book Light -- The Physics of the Photon (CRC, 2014), both written on a scholarly level, the reader is given a comprehensive exposition of photon wave mechanics, quantum optics and quantum electrodynamics (QED). Divided into 10 parts, the book begins by exploring the relation between photon wave mechanics and quantum field theory. It then describes the theories of zero- and one-photon states and that of bi-photons. After discussing conservation laws, Lagrangian formulations, geometric phase and topology, the author turns towards the theory of photon scattering, emphasizing a density matrix operator approach and the role of microscopic extinction theorems. The book next focuses on mesoscopic QED, devoting particular attention to collective jellium excitations and photon-spin interactions. Special attention is given to the basics of the photon-magnon interaction and nonlinear superconductor electrodynamics, including the nonlinear Meissner rectification phenomenon, before studying the theory of transverse photons tied to (dressing) massive particles. The last three parts take the reader on a journey to topics usually not treated in books on photon- matter interaction. Beginning with photons in curved space-time structures and in spatially curved media, e.g. Möbius bands, the author discusses the extension of QED to the electro-weak interaction at an introductory level. Fundamentals of Photon Physics ends with the establishment of the set of isovector Maxwell equations in non-Abelian SO(3) gauge theory, leading to the celebrated hedgehog monopole model. Ole Keller is professor emeritus of theoretical physics at Aalborg University, Denmark. He earned his Licentiate (∼ PhD) degree in semiconductor physics from the Danish Technical University in Copenhagen in 1972, and the Doctor of Science degree from the University of Aarhus (1996). In 1989 he was appointed as the first professor in physics at Aalborg University by Margrethe Den Anden, queen of Denmark. The same year he was admitted to Kraks Blaa Bog, a prestigious Danish biographical dictionary which (citatum) ”Includes men and women, whose life story could have an interest for a wider public”. He is a fellow of the Optical Society of America. He has written the books entitled Quantum Theory of Near-Field Electrodynamics (Springer, 2011) and LIGHT - The Physics of the Photon (CRC, 2014), as well as the monographs Local Fields in the Electrodynamics of Mesoscopic Media (Physics Reports, 1996) and On the Theory of Spatial Localization of Photons (Physics Reports, 2005). He is the editor of the books Nonlinear Optics in Solids (Springer, 1990), Studies in Classical and Quantum Nonlinear Optics (Nova Science, 1995) and Notions and Perspectives of Nonlinear Optics (World Scientific, 1996). In recent years he has carried out theoretical research in fundamental photon physics, microscopic few-photon diffraction, mesoscopic and Möbius band electrodynamics, and studied magnetic monopole theory based on QED and the isovector Maxwell equations in non-Abelian gauge symmetry.

CRC Press eBooks•Aug 6, 2024•3 citations

The essence of light

Physicist Zheng shengming

In the process of exploring the essence of light, Newton initially agreed with the particle interpretation of light while Huygens argued for the wave theory. Hence, these two theories had been disputed in Newton's time. In the beginning people accepted the particle theory, but after Thomas Young's experiment and Augustin Jean Fresnel's experiment, people began to accept the wave theory. Until Einstein proposed the quanta concept, which was later called photon, and, even later, De Broglie proposed the wave nature of matter, subsequently, people began using particle-wave duality to explicate all phenomena in micro world. Thus here appears a paradox: how can one particle exist in two forms? To solve this enigma, I have done some experiments; discover that moving photons create force; this effect reveal the phenomenon of light wave property - the inference fringes is caused by force which moving photons produced. The essence of light is particle but not particle-wave duality.

•Oct 6, 2021•0 citations

The essence of light

Physicist Zheng shengming

In the process of exploring the essence of light, Newton initially agreed with the particle interpretation of light while Huygens argued for the wave theory. Hence, these two theories had been disputed in Newton’s time. In the beginning people accepted the particle theory, but after Thomas Young’s experiment and Augustin Jean Fresnel’s experiment, people began to accept the wave theory. Until Einstein proposed the quanta concept, which was later called photon, and, even later, De Broglie proposed the wave nature of matter, subsequently, people began using particle-wave duality to explicate all phenomena in micro world. Thus here appears a paradox: how can one particle exist in two forms? To solve this enigma, I have done some experiments; discover that moving photons create force; this effect reveal the phenomenon of light wave property - the inference fringes is caused by force which moving photons produced. The essence of light is particle but not particle-wave duality.

•Oct 6, 2021•8 citations

The Enigma that is Light

Jeremy Dunning-Davies, Richard Lawrence Norman

The presently accepted notion of wave/particle duality, especially when applied to light, is undoubtedly a cause of great unease for many. Here the issue is examined afresh in the light of ideas put forward in recent years, especially by Mayants, while not forgetting the contributions of those great scientists of the past. Explanations and interpretations are then offered to account for seemingly paradoxical effects.

•Jun 1, 2016•0 citations
Focusing on the unresolved debate between Newton and Huygens from 300 years ago, The Nature of Light: What is a Photon? discusses the reality behind enigmatic photons. It explores the fundamental issues pertaining to light that still exist today. Gathering contributions from globally recognized specialists in electrodynamics and quantum optics, the book begins by clearly presenting the mainstream view of the nature of light and photons. It then provides a new and challenging scientific epistemology that explains how to overcome the prevailing paradoxes and confusions arising from the accepted definition of a photon as a monochromatic Fourier mode of the vacuum. The book concludes with an array of experiments that demonstrate the innovative thinking needed to examine the wave-particle duality of photons. Looking at photons from both mainstream and out-of-box viewpoints, this volume is sure to inspire the next generation of quantum optics scientists and engineers to go beyond the Copenhagen interpretation and formulate new conceptual ideas about light-matter interactions and substantiate them through inventive applications.
Have you ever tried to define light? If so, your definition is probably related to vision, the ability to see things. The Merriam-Webster English dictionary defines light as “something that makes vision possible”. However, the definition of the “nature of light” is a complex term already discussed by philosophers of Ancient Greece. In the 17th century, the debate on the matter focused on whether light was a particle or a wave, based on the different properties of light that had been gradually discovered over time. Isaac Newton (1642−1727) was a defender of the corpuscular theory of light, which considered light to be formed by particles, i.e., small pieces of matter, like dust or grains of sand. He was the author of Opticks (1706), the front cover of which appears in Fig. 1.1. Christian Huygens (1629–1695), on the other hand, supported the theory that light is a wave. These are two completely different definitions of the same physical concept. A range of experiments were developed to attempt to clarify this dilemma, but it was only until 1900 when Max Planck (1858-1947) introduced the basis of a theory that would go on to revolutionize scientific thinking, marking the beginning of modern physics: quantum theory. Developed during the 20th century thanks to advances made by scientists such as Niels Bohr, Born, Heisenberg, Schrödinger, Pauli, Dirac, Einstein or de Broglie, quantum theory clarified that light is neither a particle nor a wave, but that it has a dual nature: it behaves like a wave as it spreads but like a particle in its interactions with matter. In this book, we will specify where necessary whether light behaves as a particle or as a wave, although in most cases we refer to rays of light, which always represent the direction of propagation of light.
concept is one of the most debated issues in the history of physical science. Some thirty years ago, we published an article in Physics Today entitled The Concept of the Photon, 1 in which we described the photon as a classical electromagnetic field plus the fluctuations associated with the vacuum. However, subsequent developments required us to envision the as an intrinsically quantum mechanical entity, whose basic physics is much deeper than can be explained by the simple 'classical wave plus vacuum fluctuations' picture. These ideas and the extensions of our conceptual understanding are discussed in detail in our recent quantum optics book. 2 In this article we revisit the concept based on examples from these sources and more.
The photon, an abstract concept belonging to a global vacuum, only manifests itself during interaction with matter. Fundamentals of Photon Physics describes the richly faceted, basic theory of photon-matter interaction, selecting a wide number of topics. Together with the author’s book Light -- The Physics of the Photon (CRC, 2014), both written on a scholarly level, the reader is given a comprehensive exposition of photon wave mechanics, quantum optics and quantum electrodynamics (QED). Divided into 10 parts, the book begins by exploring the relation between photon wave mechanics and quantum field theory. It then describes the theories of zero- and one-photon states and that of bi-photons. After discussing conservation laws, Lagrangian formulations, geometric phase and topology, the author turns towards the theory of photon scattering, emphasizing a density matrix operator approach and the role of microscopic extinction theorems. The book next focuses on mesoscopic QED, devoting particular attention to collective jellium excitations and photon-spin interactions. Special attention is given to the basics of the photon-magnon interaction and nonlinear superconductor electrodynamics, including the nonlinear Meissner rectification phenomenon, before studying the theory of transverse photons tied to (dressing) massive particles. The last three parts take the reader on a journey to topics usually not treated in books on photon- matter interaction. Beginning with photons in curved space-time structures and in spatially curved media, e.g. Möbius bands, the author discusses the extension of QED to the electro-weak interaction at an introductory level. Fundamentals of Photon Physics ends with the establishment of the set of isovector Maxwell equations in non-Abelian SO(3) gauge theory, leading to the celebrated hedgehog monopole model. Ole Keller is professor emeritus of theoretical physics at Aalborg University, Denmark. He earned his Licentiate (∼ PhD) degree in semiconductor physics from the Danish Technical University in Copenhagen in 1972, and the Doctor of Science degree from the University of Aarhus (1996). In 1989 he was appointed as the first professor in physics at Aalborg University by Margrethe Den Anden, queen of Denmark. The same year he was admitted to Kraks Blaa Bog, a prestigious Danish biographical dictionary which (citatum) ”Includes men and women, whose life story could have an interest for a wider public”. He is a fellow of the Optical Society of America. He has written the books entitled Quantum Theory of Near-Field Electrodynamics (Springer, 2011) and LIGHT - The Physics of the Photon (CRC, 2014), as well as the monographs Local Fields in the Electrodynamics of Mesoscopic Media (Physics Reports, 1996) and On the Theory of Spatial Localization of Photons (Physics Reports, 2005). He is the editor of the books Nonlinear Optics in Solids (Springer, 1990), Studies in Classical and Quantum Nonlinear Optics (Nova Science, 1995) and Notions and Perspectives of Nonlinear Optics (World Scientific, 1996). In recent years he has carried out theoretical research in fundamental photon physics, microscopic few-photon diffraction, mesoscopic and Möbius band electrodynamics, and studied magnetic monopole theory based on QED and the isovector Maxwell equations in non-Abelian gauge symmetry.
In the process of exploring the essence of light, Newton initially agreed with the particle interpretation of light while Huygens argued for the wave theory. Hence, these two theories had been disputed in Newton's time. In the beginning people accepted the particle theory, but after Thomas Young's experiment and Augustin Jean Fresnel's experiment, people began to accept the wave theory. Until Einstein proposed the quanta concept, which was later called photon, and, even later, De Broglie proposed the wave nature of matter, subsequently, people began using particle-wave duality to explicate all phenomena in micro world. Thus here appears a paradox: how can one particle exist in two forms? To solve this enigma, I have done some experiments; discover that moving photons create force; this effect reveal the phenomenon of light wave property - the inference fringes is caused by force which moving photons produced. The essence of light is particle but not particle-wave duality.
In the process of exploring the essence of light, Newton initially agreed with the particle interpretation of light while Huygens argued for the wave theory. Hence, these two theories had been disputed in Newton’s time. In the beginning people accepted the particle theory, but after Thomas Young’s experiment and Augustin Jean Fresnel’s experiment, people began to accept the wave theory. Until Einstein proposed the quanta concept, which was later called photon, and, even later, De Broglie proposed the wave nature of matter, subsequently, people began using particle-wave duality to explicate all phenomena in micro world. Thus here appears a paradox: how can one particle exist in two forms? To solve this enigma, I have done some experiments; discover that moving photons create force; this effect reveal the phenomenon of light wave property - the inference fringes is caused by force which moving photons produced. The essence of light is particle but not particle-wave duality.