◇◇新语丝(www.xys.org)(xys.dxiong.com)(xys.3322.org)(xys.xlogit.com)◇◇ 也谈洛仑兹、爱因斯坦和狭义相对论(一) wangyu Hooklee网友热心提供了一些关于爱因斯坦和洛仑兹的“素材”,可惜美中不足 的是,这些“素材”仅仅限于表面(也是大家都基本知道的东西)而没有揭示出 深刻的东西,即爱因斯坦是否是独立得到了洛仑兹变换?或者说,洛仑兹的工作 到底对爱因斯坦的狭义相对论贡献有多大? 例如,Hooklee 提供的“确定无疑”的共识,本人和Mayfly并没有异议; Hooklee提供的“有争议的说法”,又没有一个明确的结论,而这正是我和 Mayfly引起争执并要弄清楚的地方。另外Hooklee提供的网址,国内的读者可能 很难链接上。 在这种事情上较真,非常浪费精力,因为如果要从原始文献开始去考证的话,不 啻是一篇科学史专业的硕士或博士论文了。我本来不想多说什么,但考虑到新语 丝在当前也是颇有影响的一个网站,如果在这个上面被误导的话,负面影响还是 挺大的,特别容易被某些别有用心的民科或反科学文化人利用。所以本人首先试 以权威的大不列颠百科全书作为资料来源,来说明爱因斯坦推导出洛仑兹变换肯 定是参考了洛仑兹以及其他人的工作。(由于我在内部网络内得到大不列颠百科 全书,可能其他读者无法获得,故将百科全书原始内容列于文后)。以下英文选 自百科全书原文,中文为本文作者所写。 先看看洛仑兹变换。 词条1: Lorentz transformations (洛仑兹变换,全文) set of equations in relativity physics that relate the space and time coordinates of two systems moving at a constant velocity relative to each other. Required to describe high-speed phenomena approaching the speed of light, Lorentz transformations formally express the relativity concepts that space and time are not absolute; that length, time, and mass depend on the relative motion of the observer; and that the speed of light in a vacuum is constant and independent of the motion of the observer or the source. The equations were developed by the Dutch physicist Hendrik Antoon Lorentz in 1904. See also Galilean transformations. 这段英文不难理解,请注意最后一句话说明了这些equations 是由荷兰物理学家 洛仑兹developed的。而根本没有提爱因斯坦什么事,如果是两人独立得出的结 论,那么权威的大不列颠应该提到一句爱因斯坦也独立地推导出这些equations。 词条2:Lorentz, Hendrik Antoon (洛仑兹,部分内容) Dutch physicist and joint winner (with Pieter Zeeman) of the Nobel Prize for Physics in 1902 for his theory of electromagnetic radiation, which, confirmed by findings of Zeeman, gave rise to Albert Einstein's special theory of relativity. 本段最后一句, gave rise 爱因斯坦的狭义相对论。Gave rise 怎么理解?期 待英文高手指教。是不是有这个意思,即洛仑兹(或他的理论)帮助了爱因斯坦, 使之升华到狭义相对论? (中间省略部分无关的百科全书原文内容) Lorentz' electron theory was not, however, successful in explaining the negative results of the Michelson-Morley experiment, an effort to measure the velocity of the Earth through the hypothetical luminiferous ether by comparing the velocities of light from different directions. In an attempt to overcome this difficulty he introduced in 1895 the idea of local time (different time rates in different locations). 请看,洛仑兹具体的研究工作始于1895年。Lorentz arrived at the notion that moving bodies approaching the velocity of light contract in the direction of motion. The Irish physicist George Francis FitzGerald had already arrived at this notion independently (see Lorentz-FitzGerald contraction, 请注意,爱尔兰的George Francis FitzGerald (菲茨杰尔德)也独立的得出了这个结论(运动物体收缩,是洛仑 兹变换的重要内容之一),百科全书特意提到了这点。and in 1904 Lorentz extended his work and developed the Lorentz transformations. These mathematical formulas describe the increase of mass, shortening of length, and dilation of time that are characteristic of a moving body and form the basis of Einstein's special theory of relativity. (这些 公式)form 了爱因斯坦的狭义相对论的基础。话已经说得很明白了。 既然提到了洛仑兹—菲茨杰尔德收缩,我们不妨再看看百科全书中这个词条。 词条3:Lorentz-FitzGerald contraction (洛仑兹—菲茨杰尔德收缩,全文) also called space contraction, in relativity physics, the shortening of an object along the direction of its motion relative to an observer. Dimensions in other directions are not contracted. The concept of the contraction was proposed by the Irish physicist George FitzGerald in 1889, and it was thereafter independently developed by Hendrik Lorentz of The Netherlands.这里也提到了菲茨杰尔德和洛仑兹两人 各自独立地得到了(收缩)的结论。 The Michelson-Morley experiment in the 1880s had challenged the postulates of classical physics by proving that the speed of light is the same for all observers, regardless of their relative motion. FitzGerald and Lorentz attempted to preserve the classical concepts by demonstrating the manner in which space contraction of the measuring apparatus would reduce the apparent constancy of the speed of light to the status of an experimental artifact. 这段话的大意是说这两人试图在经典的物理框架(即 保留牛顿的经典物理体系)内通过所谓的“空间收缩”来解释光(对于任何一个 惯性参照系)的速度不变的实验事实,紧接着下文提到爱因斯坦的革命性时空观 In 1905 the German-American physicist Albert Einstein reversed the classical view by proposing that the speed of light is indeed a universal constant and showing that space contraction then becomes a logical consequence of the relative motion of different observers. Significant at speeds approaching that of light, the contraction is a consequence of the properties of space and time and does not depend on compression, cooling, or any similar physical disturbance. See also time dilation.这段话的意思是说,爱因斯坦完全推翻了经典的观念,而认为应 该把“光速就是一个常数(对各种惯性参照系)”当作一个基本定律,这样“空 间收缩”(属于洛仑兹变换的重要内容之一)就是顺理成章的事情了,这实际上 是用崭新的物理观点重新诠释了(已有的,已发表的)洛仑兹变换。 词条4:FitzGerald, George Francis (菲茨杰尔德,部分) physicist who first suggested a method of producing radio waves, thus helping to lay the basis of wireless telegraphy. He also developed a theory, now known as the Lorentz–FitzGerald contraction, which Einstein used in his own special theory of relativity. 这里也提到了他 也developed了洛仑兹—菲茨杰尔德收缩(属于洛仑兹变换的一个重要内容), 并且被爱因斯坦用于其狭义相对论。 Independently of Hendrik A. Lorentz of The Netherlands, FitzGerald studied the results of the Michelson–Morley experiment (1887) and arrived at a similar conclusion. The experiment was an attempt to measure the Earth's motion relative to the pervasive luminiferous ether postulated as the medium within which light waves were propagated. The attempt failed to detect any such motion. In 1892 FitzGerald suggested that when in motion, a body is shorter (along its line of motion) than when at rest and that such a shortening, or contraction, affects the instruments used in the experiment. Lorentz arrived at this idea independently in 1895 and developed it considerably. 这段话 说明最早是菲茨杰尔德于1892年提出了“收缩”的概念。最后斜体字部分提到了 洛仑兹于1895年独立的得出了相同的结论,虽然洛仑兹时间晚3年左右,但是显 然有证据表明,洛仑兹原先并不知道菲茨杰尔德的工作,这也得到了业界的认可, 所以才会写入百科全书。A collection, The Scientific Writings of the Late George Francis FitzGerald, was published in 1902. 当然,我们还应该再看看爱因斯坦的词条(见附件),果然,一句话都没有提到 洛仑兹变换。 结论,老外的百科全书还是比较公正的,该有的贡献不会给你漏掉,没有的也不 会给你凭空加上。如果爱因斯坦确实是独立地推导出洛仑兹变换,那么按照学界 惯例,这个变换应该叫做“洛仑兹—爱因斯坦变换”。这一部分的研究都是从 1887年的Michelson–Morley experiment(迈克耳逊—莫雷实验)开始的,为了 解释该实验结果和经典物理完全相悖的事实,即光速对任意的惯性参照系都是常 数。最早地工作始于菲茨杰尔德和洛仑兹,后来参加的有彭加勒和爱因斯坦等。 实际上,爱因斯坦只是用崭新的物理观点重新诠释了(已有的,已发表的)洛仑 兹变换,但这,一点也不影响其光辉形象,相反,能提出革命性观点及理论(并 且其理论导出的结论在以后的物理实验中被证实)的人是相当伟大的。 附件:为方便某些读者,补齐本文中有关的大不列颠百科全书词条 1.Lorentz, Hendrik Antoon born July 18, 1853, Arnhem, Neth. died Feb. 4, 1928, Haarlem Dutch physicist and joint winner (with Pieter Zeeman) of the Nobel Prize for Physics in 1902 for his theory of electromagnetic radiation, which, confirmed by findings of Zeeman, gave rise to Albert Einstein's special theory of relativity. In his doctoral thesis at the University of Leiden (1875), Lorentz refined the electromagnetic theory of James C. Maxwell of England so that it more satisfactorily explained the reflection and refraction of light. He was appointed professor of mathematical physics at Leiden in 1878. His work in physics was wide in scope, but his central aim was to construct a single theory to explain the relationship of electricity, magnetism, and light. Although, according to Maxwell's theory, electromagnetic radiation is produced by the oscillation of electric charges, the charges that produce light were unknown. Since it was generally believed that an electric current was made up of charged particles, Lorentz later theorized that the atoms of matter might also consist of charged particles and suggested that the oscillations of these charged particles (electrons) inside the atom were the source of light. If this were true, then a strong magnetic field ought to have an effect on the oscillations and therefore on the wavelength of the light thus produced. In 1896 Zeeman, a pupil of Lorentz, demonstrated this phenomenon, known as the Zeeman effect, and in 1902 they were awarded the Nobel Prize. Lorentz' electron theory was not, however, successful in explaining the negative results of the Michelson-Morley experiment, an effort to measure the velocity of the Earth through the hypothetical luminiferous ether by comparing the velocities of light from different directions. In an attempt to overcome this difficulty he introduced in 1895 the idea of local time (different time rates in different locations). Lorentz arrived at the notion that moving bodies approaching the velocity of light contract in the direction of motion. The Irish physicist George Francis FitzGerald had already arrived at this notion independently (see Lorentz-FitzGerald contraction, and in 1904 Lorentz extended his work and developed the Lorentz transformations. These mathematical formulas describe the increase of mass, shortening of length, and dilation of time that are characteristic of a moving body and form the basis of Einstein's special theory of relativity. In 1912 Lorentz became director of research at the Teyler Institute, Haarlem, though he remained honorary professor at Leiden, where he gave weekly lectures. 2.FitzGerald, George Francis born Aug. 3, 1851, Dublin died Feb. 22, 1901, Dublin physicist who first suggested a method of producing radio waves, thus helping to lay the basis of wireless telegraphy. He also developed a theory, now known as the Lorentz–FitzGerald contraction, which Einstein used in his own special theory of relativity. FitzGerald became a tutor at Trinity College in Dublin in 1877 and professor of natural and experimental philosophy in 1881. From his studies of radiation he concluded that an oscillating electric current would produce electromagnetic waves. This finding was later verified experimentally by Heinrich R. Hertz of Germany and used in the development of wireless telegraphy. Independently of Hendrik A. Lorentz of The Netherlands, FitzGerald studied the results of the Michelson–Morley experiment (1887) and arrived at a similar conclusion. The experiment was an attempt to measure the Earth's motion relative to the pervasive luminiferous ether postulated as the medium within which light waves were propagated. The attempt failed to detect any such motion. In 1892 FitzGerald suggested that when in motion, a body is shorter (along its line of motion) than when at rest and that such a shortening, or contraction, affects the instruments used in the experiment. Lorentz arrived at this idea independently in 1895 and developed it considerably. A collection, The Scientific Writings of the Late George Francis FitzGerald, was published in 1902. 3.Einstein, Albert born March 14, 1879, Ulm, Württemberg, Germany died April 18, 1955, Princeton, New Jersey, U.S. German-American physicist who developed the special and general theories of relativity and won the Nobel Prize for Physics in 1921 for his explanation of the photoelectric effect. In the first 15 years of the 20th century, Einstein—recognized in his own time as one of the most creative intellects in human history—advanced a series of theories that proposed entirely new ways of thinking about space, time, and gravitation. His theories of relativity and gravitation were a profound advance over the old Newtonian physics and revolutionized scientific and philosophical inquiry. Herein lay the unique drama of Einstein's life. He was a self-confessed lone traveler; his mind and heart soared with the cosmos, yet he could not armour himself against the intrusion of the often horrendous events of the human community. Almost reluctantly he admitted that he had a “passionate sense of social justice and social responsibility.” His celebrity gave him an influential voice that he used to champion such causes as pacifism, liberalism, and Zionism. The irony for this idealistic man was that his famous postulation of an energy-mass equation, which states that a particle of matter can be converted into an enormous quantity of energy, had its spectacular proof in the creation of the atomic and hydrogen bombs, the most destructive weapons ever known. (XYS20060730) ◇◇新语丝(www.xys.org)(xys.dxiong.com)(xys.3322.org)(xys.xlogit.com)◇◇