Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

CRC Press eBooks

Quantum Theory of Light: Field Quantization and Photon

Yanhua H. Shih

Published Dec 16, 2020• 0 citations
Publisher

Abstract

The quantum theory of light began in the early 20th century. The successful introduction of the concept of photon, or light quantum, stimulated a new foundation of physics, namely, the quantum theory. Today, quantum theory has turned out to be the overarching principle of modern physics. It would be difficult to find a single subject among the physical sciences which is not affected in its foundations or in its applications by quantum theory. The photon is a wave: it has no mass, it travels at the highest speed in the universe, and it interferes with itself. The photon is a particle: it has well-defined values of momentum and energy, and it even “spins” like a particle. Around the year of 1900, an unexpected observation happened in experimental physics. It was found that the experimentally observed spectral distribution of blackbody radiation disagreed with the theoretical predications of classical physics.

DOI
10.1201/9781003130604-2

Related papers

Quantum Theory of Light: Light Quantum and Field Quantization

Yanhua H. Shih

In the beginning of 20th century, the successful introduction of the concept of light quantum, or photon, inspired a new foundation of physics, namely, the quantum theory. Today, quantum theory has turned out to be the overarching principle of modern physics. It would be difficult to find a single subject among the physical sciences which is not affected in its foundations or in its applications by quantum theory.

•Nov 1, 2025•0 citations

From the Light Quantum to the Photon: The Evolution of a Physical Concept

Aaron Collavini, Valentina Bologna, Francesco Longo +2 more

This work examines the physical and conceptual evolution of the light quantum from Planck's blackbody theory to the theoretical and experimental developments that led to the quantization of the electromagnetic field. The present study shows that the decisive transition occurred in Einstein's quantum theory of radiation (1916-1917). Absorption, stimulated emission, and spontaneous emission were formulated as elementary probabilistic mechanisms whose statistical balance alone reproduces the blackbody spectrum. In particular, spontaneous emission requires the emission of a light quantum, thereby implicitly proving its physical necessity before its theoretical status was clarified. At the same time, the already existing term photon began to acquire a stable usage following Lewis's 1926 proposal and became increasingly associated with Einstein's light quantum. By the mid-1920s, the central problem had shifted from whether light quanta were physically required to how radiation could be incorporated into the emerging quantum-mechanical formalism. This transition marks a key stage, illustrating how initial debates about the existence of light quanta gave way to their integration into a comprehensive theoretical structure. The resulting asymmetry between the novel quantum description of matter and the still-classical description of radiation, called into question by the phenomenon of spontaneous emission, identifies the physical problem that led to the quantization of the electromagnetic field.

physics.hist-phCross-listedarXiv:2609.04985•Sep 7, 2026

Quantum Theory: An Approach Quantized on its Evolution - Part I

Fernanda K. C. Félix, Pedro G. B. Bonfim, Lucas Samuel Soares dos Santos +1 more

The Interest in the interaction of electromagnetic radiation with matter was the first impulse to structure a series of formulas, postulates and theories that would become the foundation for quantum physics.Under the shadow of statistical determinism, in the XIX and XX centuries, started the studies on the blackbody radiation, a consequent reformulation of various theories of classical physics and the introduction of the concepts of energy quantization, radiation and particles.This article will deal, briefly and chronologically, with the evolution of the old quantum theory.

Revista Virtual de Química•Jan 1, 2016•0 citations

Quantum Revolution, Speed Up of Time, and Crisis in Philosophy

Anil Rajimwale

The quantum revolution in physics of the 20th century has completely transformed the nature not only of physics and science in general, but also of philosophy and our worldview. Quantum revolution began in the early 19th century with the discovery of ‘quantum’ (plural ‘quanta’) principally by Max Planck, and with theories and discoveries in the field of relativity, linked inseparably with the name of Albert Einstein. Max Planck came across the quanta when he was studying what is known as the ‘blackbody radiation’. In classical physics in particular and the classical world in general, there was no serious problems with objects, objectivity and ontology. In classical physics, particles and fields have an existence independent of the observer. In broader view, everything, the world, exists independent of the observer and of the consciousness. The first quantum-mechanical theories on electron in mid-1920s did not take into account the effect of velocity of light, and were therefore non-relativistic.

Routledge eBooks•Jul 22, 2022•0 citations

1A Brief Overview of the Quantum Theory of Electromagnetic Fields

Michael A. Parker

The study of light through the centuries has produced a number of theories and experiments. Newton advanced the corpuscular theory, building on the early Greek view of matter composed of atoms. Then Young essentially proved the wave nature of light through the interference experiments. Maxwell provided the firm theoretical basis for the wave nature. During the late 1800s and early 1900s, further experiments showed predictions based on a continuous wave led to the well-known ultraviolet catastrophe. Plank and Einstein originated and developed the notion of the photon as an elementary quantum of propagating electromagnetic (EM) energy. The first half of the 20th century saw the development of the field quantization and the quantum electrodynamics (QED). Feynmann labeled QED as ‘‘the best theory we have’’ to describe the matter-light interaction. The second half of the 20th century witnessed the development of the coherent and squeezed optical states attributable to Glauber and Yuen. The study of light and electromagnetic fields has a long history. This chapter explores the nature of light in terms of quantum optics.

CRC Press eBooks•Oct 3, 2018•0 citations

Quantum Mechanics

Carlos Calle

Einstein’s 1905 paper on the photoelectric effect, in which he considered Planck’s idea of quanta of energy to be a universal characteristic of light, marks the beginning of quantum theory. For over ten years Einstein stood alone on the issue of energy quantization of light; and although in 1915 experimental conrmation of his photoelectric effect came from painstaking experiments performed by Millikan, acceptance of the idea that light was composed of particles was far from universal. Millikan himself wrote in 1915: “Despite … the apparent complete success of the Einstein equation, the physical theory of which it was designed to be the symbolic expression is found so untenable that Einstein himself, I believe, no longer holds to it.” Einstein did hold to it. It was only in the mid 1920s, when Heisenberg, Schrödinger, Dirac, and others developed the rst forms of quantum theory, that serious discussions concerning the particle nature of light and the meaning of the new theory began. Discussions about the meaning of quantum theory continue today.

CRC Press eBooks•Dec 22, 2009•0 citations
The quantum theory of light began in the early 20th century. The successful introduction of the concept of photon, or light quantum, stimulated a new foundation of physics, namely, the quantum theory. Today, quantum theory has turned out to be the overarching principle of modern physics. It would be difficult to find a single subject among the physical sciences which is not affected in its foundations or in its applications by quantum theory. The photon is a wave: it has no mass, it travels at the highest speed in the universe, and it interferes with itself. The photon is a particle: it has well-defined values of momentum and energy, and it even “spins” like a particle. Around the year of 1900, an unexpected observation happened in experimental physics. It was found that the experimentally observed spectral distribution of blackbody radiation disagreed with the theoretical predications of classical physics.
This work examines the physical and conceptual evolution of the light quantum from Planck's blackbody theory to the theoretical and experimental developments that led to the quantization of the electromagnetic field. The present study shows that the decisive transition occurred in Einstein's quantum theory of radiation (1916-1917). Absorption, stimulated emission, and spontaneous emission were formulated as elementary probabilistic mechanisms whose statistical balance alone reproduces the blackbody spectrum. In particular, spontaneous emission requires the emission of a light quantum, thereby implicitly proving its physical necessity before its theoretical status was clarified. At the same time, the already existing term photon began to acquire a stable usage following Lewis's 1926 proposal and became increasingly associated with Einstein's light quantum. By the mid-1920s, the central problem had shifted from whether light quanta were physically required to how radiation could be incorporated into the emerging quantum-mechanical formalism. This transition marks a key stage, illustrating how initial debates about the existence of light quanta gave way to their integration into a comprehensive theoretical structure. The resulting asymmetry between the novel quantum description of matter and the still-classical description of radiation, called into question by the phenomenon of spontaneous emission, identifies the physical problem that led to the quantization of the electromagnetic field.
The Interest in the interaction of electromagnetic radiation with matter was the first impulse to structure a series of formulas, postulates and theories that would become the foundation for quantum physics.Under the shadow of statistical determinism, in the XIX and XX centuries, started the studies on the blackbody radiation, a consequent reformulation of various theories of classical physics and the introduction of the concepts of energy quantization, radiation and particles.This article will deal, briefly and chronologically, with the evolution of the old quantum theory.
The quantum revolution in physics of the 20th century has completely transformed the nature not only of physics and science in general, but also of philosophy and our worldview. Quantum revolution began in the early 19th century with the discovery of ‘quantum’ (plural ‘quanta’) principally by Max Planck, and with theories and discoveries in the field of relativity, linked inseparably with the name of Albert Einstein. Max Planck came across the quanta when he was studying what is known as the ‘blackbody radiation’. In classical physics in particular and the classical world in general, there was no serious problems with objects, objectivity and ontology. In classical physics, particles and fields have an existence independent of the observer. In broader view, everything, the world, exists independent of the observer and of the consciousness. The first quantum-mechanical theories on electron in mid-1920s did not take into account the effect of velocity of light, and were therefore non-relativistic.
The study of light through the centuries has produced a number of theories and experiments. Newton advanced the corpuscular theory, building on the early Greek view of matter composed of atoms. Then Young essentially proved the wave nature of light through the interference experiments. Maxwell provided the firm theoretical basis for the wave nature. During the late 1800s and early 1900s, further experiments showed predictions based on a continuous wave led to the well-known ultraviolet catastrophe. Plank and Einstein originated and developed the notion of the photon as an elementary quantum of propagating electromagnetic (EM) energy. The first half of the 20th century saw the development of the field quantization and the quantum electrodynamics (QED). Feynmann labeled QED as ‘‘the best theory we have’’ to describe the matter-light interaction. The second half of the 20th century witnessed the development of the coherent and squeezed optical states attributable to Glauber and Yuen. The study of light and electromagnetic fields has a long history. This chapter explores the nature of light in terms of quantum optics.
Einstein’s 1905 paper on the photoelectric effect, in which he considered Planck’s idea of quanta of energy to be a universal characteristic of light, marks the beginning of quantum theory. For over ten years Einstein stood alone on the issue of energy quantization of light; and although in 1915 experimental conrmation of his photoelectric effect came from painstaking experiments performed by Millikan, acceptance of the idea that light was composed of particles was far from universal. Millikan himself wrote in 1915: “Despite … the apparent complete success of the Einstein equation, the physical theory of which it was designed to be the symbolic expression is found so untenable that Einstein himself, I believe, no longer holds to it.” Einstein did hold to it. It was only in the mid 1920s, when Heisenberg, Schrödinger, Dirac, and others developed the rst forms of quantum theory, that serious discussions concerning the particle nature of light and the meaning of the new theory began. Discussions about the meaning of quantum theory continue today.