〈Articles〉The History of Quantum Theory; its Conceptual Development and the Philosophical Implications―From the Black-Body Radiation to the Planck's Quantum Hypothesis―
[概要]量子力学は, 現代の科学技術文明にとってもっとも重要な理論である. 量子なる概念は, 二十世紀初頭に出現した. これを量子革命と称する. われわれは, 本論で量子論の発展過程を見てゆく. とりわけ本論が主題とするのは, 黒体放射の問題がいかに解き明かされてプランクの放射公式に結実したか, ということである. かかる議論の過程で, われわれは, 量子の二重性がどのようにして出現したのかが明確にされるのを見るであろう. 言い替えれば, 量子の二面性の根源が, 完成された理論のどこに潜んでいるかを見いだすであろう. また, 本論は, 量子の認識論に関して, その哲学的含意についても若干の議論をすることになる. [Abstract] Quantum mechanics is the most important theory for the modern scientific and technological civilization. The notion of quantum had been emerged at the beginning of the 20th century that is called quantum revolution. We will see the process of the development of the quantum theory in this paper. Especially, we will see and discuss how the black-body problem had been solved by the Planck's formula for radiation. This discussion will make a clear understanding to the emergence of the so-called wave-particle duality. That is to say, we will see the origins of the quantum duality that are hid behind of the accomplished theory. And we discuss a few philosophical implications that are about the epistemology of quantum.
[概要]量子力学は, 現代の科学技術文明にとってもっとも重要な理論である. 量子なる概念は, 二十世紀初頭に出現した. これを量子革命と称する. われわれは, 本論で量子論の発展過程を見てゆく. とりわけ本論が主題とするのは, 黒体放射の問題がいかに解き明かされてプランクの放射公式に結実したか, ということである. かかる議論の過程で, われわれは, 量子の二重性がどのようにして出現したのかが明確にされるのを見るであろう. 言い替えれば, 量子の二面性の根源が, 完成された理論のどこに潜んでいるかを見いだすであろう. また, 本論は, 量子の認識論に関して, その哲学的含意についても若干の議論をすることになる. [Abstract] Quantum mechanics is the most important theory for the modern scientific and technological civilization. The notion of quantum had been emerged at the beginning of the 20th century that is called quantum revolution. We will see the process of the development of the quantum theory in this paper. Especially, we will see and discuss how the black-body problem had been solved by the Planck's formula for radiation. This discussion will make a clear understanding to the emergence of the so-called wave-particle duality. That is to say, we will see the origins of the quantum duality that are hid behind of the accomplished theory. And we discuss a few philosophical implications that are about the epistemology of quantum.
[概要] 量子なる概念は, プランクの放射公式によって議論に俎上した. しかし, それは未だ単なる関数的関係にすぎず, リアルで現実的な物理的実体ではなかった. プランクの量子は現実存在ではないのである. これに対してアインシュタインは, 光量子仮説を導入することで, 量子をリアルでビビッドな存在とし, 量子は実体となった. これは, 量子を粒子として実体化することでもあった. われわれは, 本論において, このアインシュタインのアイデアと実体化の過程を詳細に追跡し, 幾ばくかの哲学的側面についての考察も行う. また, 考察の過程で波動一粒子の二重性の根源についての議論も行うこととなる. [Abstract] The concept of quantum came up in the discussions by the Planck's formula for radiation. However, it was a merely a functional relation, but not physical substance that is the reality. Planck's quantum does not have a real existence at all. In contrast with this, Einstein proposed the hypothesis of the light quanta as a real and with a vivid existence. Thus the quantum becomes a physical substance. This is also a substantiation of quantum as particles. We will see the process of this substantiation and the developments of the Einstein's idea in this article in details and have a few philosophical discussions about this process. We will see and also argue about the roots of the wave-particle duality.
[概要]本研究ノートは後続する量子論の歴史に対する序論である. 現代と19世紀の間にある種の深い断絶があるように量子論と古典物理学の間にも断絶が存在する. ここに量子の歴史をあらためて記してみる意義がある. 本論では, 19世紀の物理学（古典物理学）の世界観と量子を生み出す社会の直接的な要因と目されるその社会状況を概観しておく. また, 現代がいかに視角や展望を必要としているかについても若干の私論を展開しておくものである. [Abstract] This paper is an introduction for the history of quantum theory that I will write on the subsequent articles. To write the history of quantum is important because we are living in the modern scientific civilization. However, we have deep chasms between classical 19th century world and the modern world. There are also chasms between classical physics and the quantum modern physics. We will argue a world-picture of the classical physics and social circumstances which provided for the birth of the quantum in this paper. And this paper states and expounds the necessity of the perspective into our era as my personal views too.
This narrative review traces the conceptual and experimental evolution of quantum mechanics, beginning from the inadequacies of classical physics to explain phenomena like blackbody radiation and the photoelectric effect. It highlights pivotal developments, including Planck?s quantum hypothesis, Einstein?s photon theory, Bohr?s atomic model, and the establishment of wave-particle duality through de Broglie and Schr?dinger?s work. The review also delves into the philosophical implications of quantum theory, including the observer effect, uncertainty principle, and quantum entanglement. Through a cohesive historical lens, the article articulates the transformative journey of quantum mechanics into a fundamental pillar of modern physics.
The theory of relativity is essentially the culmination of classical physics. Although revisions in our concepts of space and time are necessitated by both the special and general theories of relativity, the notion of causality, in which a cause precedes its effect, remains intact in the relativistic formulations of electrodynamics and mechanics and of gravitation. An upper limit is set on the speed of bodies, and of the propagation of energy, and physical quantities are often defined operationally, but once we adjust ourselves to these new rules, our representations of physical processes proceed pretty much as they did in classical physics. On the other hand, quantum theory seems to require a much more profound philosophical revision of our thought patterns. Even the viability of the usual meaning of a causal connection between one event and another is there called into question. SOME HISTORICAL BACKGROUND We begin with a brief and highly selective review of the experimental and theoretical problems that formed the conceptual backdrop to the emergence of quantum theory. We focus attention first on an important phenomenon – blackbody radiation – that was instrumental for the formulation of quantum mechanics. A blackbody is defined as a surface that absorbs all of the electromagnetic radiation that falls onto it. It is picturesquely so named since any light incident on such a body would be absorbed, making it appear black (at least at typical temperatures in our environment). A blackbody also emits radiation.
Quantum mechanics is one of the great success stories of modern physics, making sense of the very small just as Einstein's theory of relativity made sense of the very large. But, for most students, the ideas that make quantum mechanics powerful can be confusing and counterintuitive. This volume in the Greenwood Guides to Great Ideas in Science series provides a history of quantum mechanics from the early breakthroughs of Planck and Einstein, at the beginning of the 20th century, to the present frontiers of quantum computing and quantum gravity. The approach is entirely non-technical, and is aimed at the general reader who may not have much mathematical background but who has a strong curiosity about some of the most important developments in modern science. Quantum Mechanics: A Historical Perspectivetraces the history of this powerful theory, including: ; The early discoveries by Max Planck and Albert Einstein regarding the quantization of radiation ; The early quantum theory, including Neils Bohr's theory of the atom ; The birth of modern quantum mechanics through the work of Heisenberg, Schrodinger, Born, Dirac and others ; Applications of quantum mechanics in chemistry, nuclear physics, electronics, and many other areas ; Recent work in quantum computation and quantum information theory The book emphasizes the fact that despite the great success of quantum mechanics, many exciting intellectual frontiers remain open for further researchers to explore. It includes a glossary, a timeline, and a bibliography of accessible resources for further research.
The quantum revolutions: from concepts to technology The development of quantum mechanics in the beginning of the twentieth century was a unique intellectual adventure, which obliged scientists and philosophers to change radically the concepts they used to describe the world. After these heroic efforts, it became possible to understand the stability of matter, the mechanical and thermal properties of materials, the interaction between radiation and matter, and many other properties of the microscopic world that had been impossible to understand with classical physics. A few decades later, that conceptual revolution enabled a technological revolution , at the root of our information-based society. It is indeed with the quantum mechanical understanding of the structure and properties of matter that physicists and engineers were able to invent and develop the transistor and the laser – two key technologies that now permit the high-bandwidth circulation of information, as well as many other scientific and commercial applications. After such an accumulation of conceptual – and eventually technological – successes, one might think that by 1960 all the interesting questions about quantum mechanics had been raised and answered. However, in his now-famous paper of 1964 – one of the most remarkable papers in the history of physics – John Bell drew the attention of physicists to the extraordinary features of entanglement: quantum mechanics describes a pair of entangled objects as a single global quantum system, impossible to be thought of as two individual objects, even if the two components are far apart.