Newton's and Huygens' Theories of Light

11 Key excerpts on "Newton's and Huygens' Theories of Light"

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  Light and Video Microscopy

  • Randy O. Wayne(Author)
  • 2019(Publication Date)
  • Academic Press

    (Publisher)

  The vibrations were equivalent to periodic changes in the density of the ether, and these variations put the light corpuscles into “easy fits of reflection or transmission.” Newton could not believe that light was a wave because he felt that if light in fact did travel as a wave, it should not only bend away from an opaque object, but it should also bend into the geometrical shadow. By contrast, Robert Hooke (Birch, 1968) thought: That light is a vibrating or tremulous motion of the medium, (which is thence called pellucid) produced from a like motion in the luminous body, after the same manner as sound was then generally explained by a tremulous motion of the medium conveying sound, produced therein by a tremulous motion of the sounding body: and that, as there are produced in sounds several harmonies by proportionate vibrations, so there are produced in light several curious and pleasant colours, by the proportionate and harmonium motions of vibrations intermingled; and as those of one are sensated by the ear, so those of the other are by the eye. As a consequence of the great achievements of Isaac Newton and the hagiographic attitude and less than critical thoughts of the followers of this great man, the corpuscular theory of light predominated, and Huygens’ and Hooke's wave theory of light lay fallow for almost 100 years (Tait, 1884, 1889). The wave theory was revived by Thomas Young (1794, 1800, 1801a), a botanist, a translator of the Rosetta stone, and a physician who was trying his hand at teaching Natural Philosophy at the Royal Institution (Peacock, 1855). While preparing his lectures, Young reviewed the similarities between sound and light, and reexamined the objections that Newton had made to the wave theory of light. Young, who studied the master, not the followers, apes, epigons, imitators, or votaries, concluded that the wave theory in fact could describe what happens to light when it undergoes diffraction as well as reflection and refraction

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  Light and Video Microscopy

  • Randy O. Wayne(Author)
  • 2013(Publication Date)
  • Academic Press

    (Publisher)

  The vibrations were equivalent to periodic changes in the density of the ether, and these variations put the light corpuscles into “easy fits of reflection or transmission.” Newton could not believe that light was a wave because he felt that if light in fact did travel as a wave, it should not only bend away from an opaque object, but it should also bend into the geometrical shadow. By contrast, Robert Hooke (Birch, 1968) thought: That light is a vibrating or tremulous motion of the medium, (which is thence called pellucid) produced from a like motion in the luminous body, after the same manner as sound was then generally explained by a tremulous motion of the medium conveying sound, produced therein by a tremulous motion of the sounding body: and that, as there are produced in sounds several harmonies by proportionate vibrations, so there are produced in light several curious and pleasant colours, by the proportionate and harmonium motions of vibrations intermingled; and as those of one are sensated by the ear, so those of the other are by the eye. As a consequence of the great achievements of Isaac Newton and the hagiographic attitude and less than critical thoughts of the followers of this great man, the corpuscular theory of light predominated, and Huygens’ and Hooke’s wave theory of light lay fallow for almost 100 years (Tait, 1884, 1889). The wave theory was revived by Thomas Young (1794, 1800, 1801a), a botanist, a translator of the Rosetta stone, and a physician who was trying his hand at teaching Natural Philosophy at the Royal Institution (Peacock, 1855). While preparing his lectures, Young reviewed the similarities between sound and light, and reexamined the objections that Newton had made to the wave theory of light. Young, who studied the master, not the followers, apes, epigones, imitators, or votaries, concluded that the wave theory in fact could describe what happens to light when it undergoes diffraction as well as reflection and refraction

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  Arthur Haas: Introduction to Theoretical Physics. Volume 1

  • Arthur Haas, T. Verschoyle(Authors)
  • 2020(Publication Date)
  • De Gruyter

    (Publisher)

  These phenomena included the diffraction of light, discovered by Grimaldi ; double refraction, discovered by Bartholinus ; the observation of the colours of thin films, first noted by Hoolce ; and the so-called Newton's rings. The obvious consequence of such a series of newly discovered fundamental phenomena (to which must be added that of dispersion, also discovered by Newton) was to lead physicists to form definite conceptions of the nature of light. Thus, almost simultaneously (about 1670), the two leading phy-cists, Newton and Huygens, came to the important conclu-sion that light must be a periodic process both as regards time and space. Huygens gave a sharper definition to the periodicity of light than Newton, by referring light to processes of mechanical vibrations. Inasmuch, however, as light is transmitted from the sun to the earth through a space which is obviously free from ponderable matter, for it would also be difficult other-wise to explain the immense value of the velocity of light, the latter could not be regarded as a wave motion of any ordinary substance. Huygens had thus no alternative but to make a hypothetical (Ether the carrier of the waves of light, such as had been previously conceived by other thinkers 256 THEORETICAL PHYSICS for other reasons. 3 As in solid or liquid bodies, so also in the aether, according to Huygens' idea, it should be possible to have elastic waves which we perceive as light. Science owes a great and lasting debt to Newton and Huygens, for they were the first to recognize the space-time periodicity and thus (in the wider sense of the word) the wave nature of light. The fact that optical waves were regarded in particular as mechanical ones is due, historically, to the tendency in physics at that time of reducing every-thing to mechanics, but this was in no way necessary.

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  The History of the Laser

  • Mario Bertolotti(Author)
  • 2004(Publication Date)
  • CRC Press

    (Publisher)

  CHAPTER 1

  WAVE AND CORPUSCULAR THEORIES OF LIGHT

  The three characters who played a central role in the history of the theory of light were Hooke, Huygens and Newton. Hooke and Newton were from Britain; Huygens was Dutch. They made notable contributions to several fields of physics, and established the basis for a modern understanding of light even though they proposed contradictory theories. One was based on a wave interpretation, while the other considered light to be composed of small particles. The two theories, which seemed irreconcilable, aroused fierce discussion and argument among both the protagonists and their supporters. A torrent of words has been written about this dispute; here we will not go deeply into the subject but limit ourselves to the most important facts.

  Robert Hooke

  Robert Hooke was born in Freshwater on the Isle of Wight in 1635 and died in London in 1703. He was a single-minded man who designed and built a number of instruments and devices: we owe to him, for example, the innovative use of the spiral spring in the balance mechanism of clocks, which allows their accurate operation. He expressed the law of proportionality between elastic deformations and strain which bears his name, performed a number of astronomical observations, and vindicated some of the work of Newton regarding the discovery of the Law of Gravitation, of which he really had only a vague intuition.

  Through meticulous observations with a 20 m long telescope that vibrated in the slightest breeze, he was the first to describe the shadow that Saturn’s ring cast on the planet and to make detailed maps of the Moon’s craters. He was an accomplished surveyor and architect who helped to rebuild London after the Great Fire of 1666. He was one of the first to articulate the concept of extinction and who suggested evolution two centuries before Charles Darwin.

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  Nineteenth-Century Aether Theories

  The Commonwealth and International Library: Selected Readings in Physics

  • Kenneth F. Schaffner, D. Ter Haar(Authors)
  • 2016(Publication Date)
  • Pergamon

    (Publisher)

  Explanations of refraction and even double refrac-tion were founded on these ieas, and worked out by Huygens using his own recently discovered principle of secondary wave propagation. For Huygens, light waves were very much like sound waves, for even though they were propagated with a considerably higher velocity than sound, they were strictly longitudinal in form. Isaac Newton, whose optical investigations both preceded and postdated Huygens' work, could not accept a wave theory of light as he was unable to see how well-defined rays and sharp shadows could be explained by such a theory. Newton favored a corpuscular theory of light, such as Huygens had rejected, which did not require an aether for quite the same reasons that Huygens' theory did, though Newton, as noted above, did use an aether for other pur-poses in his optics. Later, in 1717, Newton felt confirmed in the wisdom of his rejection of the wave theory when he discovered 2· 10 NINETEENTH-CENTURY AETHER THEORIES that a ray of light which had been obtained by double refraction differed from ordinary light in that the former possessed a direc-tional orientational property the latter did not have. Newton talks of the ray obtained from double refraction as having Sides, such as may be possessed by a rectangle but not by a circle. (Later Malus termed this property polarization.) Newton was quite convinced that a wave theory of light could not explain such a property, though a corpuscular theory might, as corpuscles them-selves could have sides. Such objections, together with Newton's growing authority in physics, brought hard days on the proponents of the wave theory of light during the eighteenth century, and accordingly on the development and acceptance of aether theories in which the aether functioned as the light medium.

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  Science In The Making

  Scientific Development As Chronicled Historic Papers In The Philosophical Magazine, with commentaries and illustrations

  • E. A. Davis(Author)
  • 1995(Publication Date)
  • CRC Press

    (Publisher)

  Part Five On the Nature of Light and Matter Part Five On the Nature of Light and Matter In the first years of the nineteenth century, Thomas Young (1773–1829) 1 demonstrated and reported several classical optical interference phænomena, thereby giving rebirth to the wave or undulatory theory of light that had been advocated much earlier—especially by Christian Huygens (1629–95), Robert Hooke (1635–1703) and Leonard Euler (1707– 83). Although the name of Sir Isaac Newton (1642–1727) is now universally associated with the opposing corpuscular or emission nature of light, Young maintained that his own conceptions had their origin in Newton’s researches. Strangely, perhaps because of faults of presentation, or because Newton’s principal objections to the wave theory—namely that it (then) failed to explain rectilinear propagation or polarization of light—held such sway amongst scientists in general, Young’s papers encountered severe criticism amongst his contemporaries in England. In France too, where Augustus J.Fresnel (1788–1827) had initiated a similar revival of the wave theory by providing very detailed mathematical descriptions of diffraction, protagonists of the corpuscular theory in that country—for example, Pierre S.de Laplace (1749–1827), Jean-Baptiste Biot (1774–1862) and Siméon D.Poisson (1781–1840)— refused to give quarter to the rival theory. Poisson in particular had deduced a seemingly untenable conclusion from Fresnel’s theory, namely that a bright spot should exist at the centre of the shadow of a small circular object. This prediction seemed so absurd to Poisson that he considered it ruled out Fresnel’s treatment altogether. Although such a bright spot was subsequently found experimentally by Dominique F.Arago (1786–1853), the wave theory continued to attract critics. Other strong experimental and theoretical support for the wave theory of light followed and, with hindsight, it seems surprising that the controversy lasted so long.

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  The Manual of Photography

  • Elizabeth Allen, Sophie Triantaphillidou(Authors)
  • 2012(Publication Date)
  • Routledge

    (Publisher)

  •  A revised interest in the study of optics in Europe after the thirteenth century led to the development of the refracting telescope. In 1621 Willebrord Snell developed the Law of Refraction, also known as Snell’s Law (page 104). Descartes independently derived the same law in 1637.

  •  Isaac Newton (1642–1727) considered light to be a stream of moving particles and this became known as corpuscular theory. The theory suggested that the particles travelled in straight lines, providing an explanation for both reflection and the casting of shadows. Famously, Newton also used a prism to disperse white light and concluded correctly that white light is made of a mixture of colours.

  •  Francesco Grimaldi (1618–1663) observed that shadows were slightly smaller than predicted due to ‘fringing’ at the edges (diffraction effects).

  •  Robert Hooke (1635–1703) proposed that light travelled in the form of a wave rather than a particle, which allowed diffraction effects to be explained as a result of constructive and destructive interference of the waves.

  •  Christian Huygens (1629–1695) further developed the idea that light was a wave in a universal medium, the ‘aether’.

  •  Thomas Young (1773–1829) experimented with shining coherent light through a pair of closely spaced slits in a screen to produce a diffraction pattern of bright and dark fringes. The results could not be easily explained by particle (corpuscular) theory and led him to further develop the wave theory of light, with the Principle of Interference. He was able to explain Newton’s results with dispersion of white light through a prism in terms of wave theory and even determined wavelengths for the colours.

  •  Michael Faraday (1791–1867) first established a relationship between light and electromagnetism. James Clerk Maxwell proved theoretically that electric and magnetic fields could continually propagate one another, travelling as a wave at a specific speed, close to experimentally determined values for the speed of light. This was a huge advance – enough to allow the theory that light was an electromagnetic wave to replace Newton’s corpuscular theory.

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  Exploring Quantum Physics through Hands-on Projects

  • David Prutchi(Author)
  • 2012(Publication Date)
  • Wiley

    (Publisher)

  Now, when a light particle travels within a medium, such as air or water, it is surrounded on all sides by the same number of matter particles. Newton explained that the attractive forces acting on a light particle would cancel each other out, allowing the light to travel in a straight line. However, near the air–water boundary, the light particle would feel more attracted by water than by air, given the water’s higher density of “matter particles.” Newton proposed that as the light particle moves into the water, it experiences an attractive force toward the water, which increases the light particle’s velocity component in the direction of the water, but not in the direction parallel to the water.

  This velocity increase in the direction perpendicular to the air–water boundary would deflect the light closer to perpendicular to the surface, which is exactly what is observed in experiments. Newton thus claimed that the velocity of light particles is different in different transparent materials, believing that light would travel faster in water than in air. (We now know this is not the case, but we’ll get to that in a minute.)

  Newton didn’t equate gravity with the attractive force between matter particles and light particles. He needed this force to be equal for all light particles crossing the boundary between two materials to explain how a prism separates white light into the colors of the rainbow. Newton proposed that the mass of a light particle depended on its color. In his view, red light particles would be more massive than violet light particles. Because of their increased inertia, red light particles would thus be deflected less when crossing the boundary between materials.

  Newton’s greatness conferred credibility to his theory, but it was not the only one around. Dutch physicist Christiaan Huygens had proposed an earlier, competing theory: light consists of waves. This was supported by the observation that two intersecting beams of light did not bounce off each other as would be expected if they were composed of particles. However, Huygens could not explain color, and the wave versus particle debate for the nature of light raged until decisive experiments were carried out in the nineteenth century.

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  Physics for O.N.C. Courses

  • R.A. Edwards(Author)
  • 2014(Publication Date)
  • Pergamon

    (Publisher)

  CHAPTER 24

  The Wave Nature of Light

  Publisher Summary

  This chapter presents the details of examination of the wave nature of light and the properties of different optical instruments. The resolving power of a telescope is the reciprocal of the smallest angle, which the line joining the two stars subtends at the objective of the telescope for which resolution of the images is just apparent. If a beam of polarized light is passed through solutions of certain substances, for example, sugar, the plane of vibration is turned through a certain angle that is proportional to the length of the path of light in the solution and to its concentration. It depends also on the nature of the substance in solution. The substance is said to be optically active. Some transparent substances become doubly refracting when subjected to stress. Examination under polarized light of models of structures made from such substances enables the amount of strain at certain points of the structure to be estimated.

  24.1 Huygens’ Wave Theory

  It was the Dutch scientist Christiaan Huygens who, in the late seventeenth century, first proposed the wave theory of light. The great rival theory of the time was the corpuscular theory of Isaac Newton who interpreted light propagation as a stream of “corpuscles” or tiny particles. This latter theory had the merit of satisfactorily explaining why light does not (at least apparently) bend round corners. Using Huygens’ theory it is more difficult to explain this fact, but as we have seen (Chapter 12 ) all wave phenomena exhibit diffraction effects and light is no exception.

  HUYGENS’ CONSTRUCTION

  Suppose S represents a very small (“point”) source of light (Fig. 24.1 ). Rays may be drawn in all directions from S representing the directions in which the light travels from it. The dotted lines represent successive positions, after equal intervals of time, of what are called wave fronts . A surface containing all points of the medium where the phase of the disturbance is instantaneously the same, as the wave advances, may be regarded as a wave front. Thus any particular “crest” or “trough” of the advancing wave can be considered as a wave front. From a point source these surfaces are spheres, concentric about the point source, and represented as circles in the figure. In the case of a parallel beam of light the successive positions of a wave front are plane surfaces normal to the direction in which the light is travelling, i.e. normal to the rays. Huygens suggested that each and every point of a wave front is to be regarded as a source of secondary wavelets and that the new position of the wave front after some interval of time t is such that it touches, tangentially, all the secondary wavelets originating from the previous position, t units of time earlier. Thus the front W (Fig. 24.2 ) advances to W′ after a time t where the radius of all the secondary wavelets from W is ct, c being the velocity of light. W′ is the “envelope” of all the secondary wavelets, i.e. W′

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  Optical Physics

  • Ariel Lipson, Stephen G. Lipson, Henry Lipson(Authors)
  • 2010(Publication Date)
  • Cambridge University Press

    (Publisher)

  He even worked out the lengths of these ‘fits’ (which came close to what we now know as half the wavelength). But the idea was very cumbersome and was not really satisfying. His contemporary Huygens (1629–95) was a supporter of the wave theory. With it he could account for diffraction and for the behaviour of two sets of waves in a crystal, without explaining how the two sets arose. Both he and Newton thought that light waves, if they existed, must be like sound waves, which are longitudinal. It is surprising that two of the greatest minds in science should have had this blind spot; if they had thought of transverse waves, the difficulties of explaining double refraction would have disappeared. 1.1.3 Triumph of the wave theory Newton’s authority kept the corpuscular theory going until the end of the eighteenth century, but by then ideas were coming forward that could not be suppressed. In 1801 Young (1773–1829) demonstrated interference fringes between waves from two sources (Fig. 1.2) – an experiment so simple to carry out and interpret that the results were incontrovertible. In 1815 Fresnel (1788–1827) worked out the theory of the Grimaldi–Hooke fringes (§7.1) and in 1821 Fraunhofer (1787–1826) invented the diffraction grating and produced diffraction patterns in parallel light for which the theory was much simpler (§9.2). These three men laid the foundation of the wave theory that is still the basis of what is now called physical optics. 5 1.2 Speed of light Figure 1.3 Fresnel and Arago’s experiment: the bright spot at the centre of the shadow of a disc. The experimental arrangement was similar to that of Young, shown in Fig. 1.2. The defeat of the corpuscular theory, at least until the days of quantum ideas, came in 1818.

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  University Physics Volume 3

  • William Moebs, Samuel J. Ling, Jeff Sanny(Authors)
  • 2016(Publication Date)
  • Openstax

    (Publisher)

  The idea that light can display both wave and particle characteristics is called wave-particle duality, which is examined in Photons and Matter Waves. In this chapter, we study the basic properties of light. In the next few chapters, we investigate the behavior of light when it interacts with optical devices such as mirrors, lenses, and apertures. Chapter 1 | The Nature of Light 7 1.1 | The Propagation of Light Learning Objectives By the end of this section, you will be able to: • Determine the index of refraction, given the speed of light in a medium • List the ways in which light travels from a source to another location The speed of light in a vacuum c is one of the fundamental constants of physics. As you will see when you reach Relativity, it is a central concept in Einstein’s theory of relativity. As the accuracy of the measurements of the speed of light improved, it was found that different observers, even those moving at large velocities with respect to each other, measure the same value for the speed of light. However, the speed of light does vary in a precise manner with the material it traverses. These facts have far-reaching implications, as we will see in later chapters. The Speed of Light: Early Measurements The first measurement of the speed of light was made by the Danish astronomer Ole Roemer (1644–1710) in 1675. He studied the orbit of Io, one of the four large moons of Jupiter, and found that it had a period of revolution of 42.5 h around Jupiter. He also discovered that this value fluctuated by a few seconds, depending on the position of Earth in its orbit around the Sun. Roemer realized that this fluctuation was due to the finite speed of light and could be used to determine c. Roemer found the period of revolution of Io by measuring the time interval between successive eclipses by Jupiter. Figure 1.2(a) shows the planetary configurations when such a measurement is made from Earth in the part of its orbit where it is receding from Jupiter.

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