The classic double-slit experiment, first performed by Young in 1801, is often cited as proving the dual wave-particle nature of light, with an emphasis on the wave aspect. In fact, when first conducted, the conclusion refuted Newton’s postulate of a corpuscular nature to light in favor of light being purely a wave. Not until the discovery of the photoelectric effect did light’s potential behavior as a particle become rejuvenated. This paper examines a possibly enhanced role for light’s corpuscular nature beyond what is currently assigned as a result of the double-slit experimental results in hope of opening yet another avenue of exploration into the still mysterious nature of light.
The classic double-slit experiment, first performed by Young in 1801, is often cited as proving the dual wave-particle nature of light, with an emphasis on the wave aspect. In fact, when first conducted, the conclusion refuted Newton’s postulate of a corpuscular nature to light in favor of light being purely a wave. Not until the discovery of the photoelectric effect did light’s potential behavior as a particle become rejuvenated. This paper examines a possibly enhanced role for light’s corpuscular nature beyond what is currently assigned as a result of the double-slit experimental results in hope of opening yet another avenue of exploration into the still mysterious nature of light.
The double-slit experiment in quantum mechanics is an experiment devised by physicist Thomas Young. It shows that light has both a wave nature or characteristic and a particle nature or characteristic, and that these natures are inseparable. So light is said to have wave–particle duality rather than be only a wave or only a particle. The same is true of electrons and other quantum particles. Although Christiaan Huygens thought that light was a wave, Isaac Newton did not. Newton felt that there were other explanations for color, and for the interference and diffraction effects that were observable at the time. Owing to Newton’s tremendous stature, his view generally prevailed. The fact that Huygens’s principle worked was not considered evidence that was direct enough to prove that light is a wave. The acceptance of the wave character of light came many years later when, in 1801, the English physicist and physician Thomas Young (1773–1829) did his now-classic double slit experiment
The evolution of light theories began with Isaac Newton's corpuscular model, which explained reflection and refraction but could not account for diffraction and interference. In contrast, Christiaan Huygens proposed a wave theory, explaining light's behavior through an ether-based medium, supported by his principle that each point in a wavefront acts as a secondary source. This idea was experimentally supported in the early nineteenth century when Thomas Young's double-slit experiment revealed an interference pattern, affirming light's wave nature. Later, James Clerk Maxwell unified electricity and magnetism, establishing light as an electromagnetic wave and extending the electromagnetic spectrum beyond visible light. In the twentieth century, Einstein's photoelectric effect introduced the concept of wave-particle duality, demonstrating that light behaves as discrete photons. Soon after, Louis de Broglie extended the idea of wave-particle duality to matter, a prediction confirmed in 1927 when Clinton Davisson and Lester Germer observed electron diffraction from a crystal and, independently, G.P. Thomson demonstrated electron diffraction through thin films, both proving that electrons also exhibit wave-like properties. This concept was dramatically visualized by Claus Jonsson's 1961 electron double-slit experiment. Recently, the ALICE collaboration observed quantum interference patterns at the femtometer scale in ultra-relativistic nuclear collisions, pushing quantum interference studies to new frontiers.
One of my favorite physics experiments was conducted by Thomas Young (1773-1829) when he demonstrated that light consists of waves by showing that the distribution of brightness by interfering beams could be explained by the additive and subtractive interference of the wavefronts. Young's experiment, performed in the early 1800s, played a vital role in the acceptance of the wave theory of light, defeating Isaac Newton's corpuscular theory which had been the accepted model of light propagation at that time. Although, a later observation by Heinrich Hertz (1857-1894) demonstrated that under different circumstances, the photoelectric effect can cause light to behave as if it is composed of discrete particles. These seemingly contradictory discoveries made it necessary to go beyond classical physics and eventually consider the quantum nature of light.
Young's double slit experiments representing the mystery of quantum mechanics have been descripted by wave theories. To study the mystery, the double slit experiments were extended to the cross-double slit experiments. A description should explain all the double slit and cross-double slit experiments consistently. To test the wave description, the two postulates are proposed, which state that before passing through the double slit and before landing on the detector, photons behave as particles, but not as waves. To test the two postulates, the comprehensive double slit/cross-double slit experiments are proposed and performed. By placing shields and/or blockers near the detector/screen, the comprehensive double slit/cross-double slit experiments show that the fringes are created independently and partially, which discloses the particle nature of photons in the double slit/crossdouble slit experiments and violates the wave descriptions. The comprehensive double slit/cross-double slit experiments provide the comprehensive phenomena for developing theoretical model to study the mystery of double slit, complementarity principle, wave-particle duality, and wave theory of light.
Science, as it is generally described at school, starts with experimental data. Scientists then have to find some hypothesis which explains these results. Using this hypothesis, a prediction is made about what might happen in a slightly different experiment. The double-slit experiment is a modified version of the setup first used by Thomas Young in 1801. Young’s version is a classic experiment that, at the time, seemed to have settled the dispute between wave and particle views of light decisively in favour of waves. The idea that particles might display some wavelike properties dates to the mid-1920s when a young PhD student called Louis De Broglie was thinking about the dual wave/particle nature of light. A quantum mechanical description of the double-slit experiment must involve a set of amplitudes governing the passage of an electron through the slits to the far detector.
Young’s double slit experiments have been descripted by wave theories, i.e., before and after passing a double slit, the light is waves. Now, we extend the double slit experiments to the comprehensive double slit experiments by utilizing Shield (showing the light is not wave), Metal tube (showing the light is not EM wves), Blocker (showing the light is particles), combination of Shield and Blocker (showing the light is particles), Photon-Chamber (showing the light is particles which produce both non-interference patterns and interference patterns), and Lens (showing the light is particles which produce non-wave and wave patterns). We propose two Postulates: “Postulate on light: light is photons before and after passing through double slit” and “Postulate on lens: light behaves same before and after passing through lens”. Then, we show the novel phenomena of the comprehensive double slit experiments: (1) the light is photons before and after passing through a double slit; (2) photons form both the non-interference patterns and the interference patterns; (3) the non-interference patterns gradually evolve to the interference patterns in the same experiment. We refer to the novel phenomena as “PhotoWave phenomena” that are universal. The comprehensive double slit experiments provide the novel phenomena for developing theoretical model further to study: (1) the nature of the light; (2) the Feynman’s mystery of the double slit; (3) the wave-particle duality; and (4) the wave theories of the light; (5) applications. A complete description should explain all the comprehensive double slit experiments consistently.