安德烈-马里·安培André-Marie Ampère

安德烈-马里·安培的父亲让-雅克·安培是一个富裕的人，在里昂拥有一所住宅，在距里昂仅10公里的波莱米厄拥有一座乡间别墅。直到安培七岁，这个家庭一年中的大部分时间都在里昂度过，只有夏季的几个月在波莱米厄度过。然而，在1782年，波莱米厄的住宅成了他们的主要居所，因为安培的父亲希望花更多时间在儿子的教育上。只有在冬季的短暂时光才在里昂度过，那时安培的父亲处理他的商业事务。

尽管没有上学，安培还是得到了极好的教育。他在自传体著作中描述了这种教育（相当奇怪地用第三人称指代自己）：-

他的父亲从未停止过对拉丁和法国文学以及几个科学分支的研习，在离他出生城市不远的乡下亲自抚养他。他从不要求他学习任何东西，但他知道如何激发他的求知欲。在能够阅读之前，年轻的安培最大的乐趣就是听布丰的自然史中的段落。

安培阅读了L'Encyclopédie中的文章，多年后弗朗索瓦·阿拉戈评论说，其中许多文章他在晚年都能全文背诵。弗朗索瓦·阿拉戈还声称，安培从第1卷开始阅读Encyclopédie，并按字母顺序阅读文章。安培后来对所有学科的分类欲望是源于这种教育，还是因为他喜欢布丰和Encyclopédie而自然喜欢分类，很难说。

有人声称安培在十二岁时就已经掌握了所有已知的数学，但这似乎有些夸张，因为根据安培自己的说法，他直到13岁才开始阅读初等数学书籍。然而安培总是对自己的能力非常自信，他确实很快就开始发展自己的数学思想，并开始撰写一篇关于conic sections的论文。安培与任何具有深厚数学知识的人都没有接触，因此他觉得自己的想法是原创的也就不足为奇了。

当安培还只有13岁时，他向里昂科学院提交了他的第一篇论文。这项工作试图解决构造一条与圆弧等长的线段的问题。他的方法涉及使用无穷小，但由于安培没有学过微积分，这篇论文被认为不值得发表。写完这篇文章后不久，安培开始阅读让·勒朗·达朗贝尔在Encyclopédie上关于微分学的文章，并意识到他必须学习更多的数学。

在里昂从一位修士那里上了几节微分和积分课后，安培开始研究莱昂哈德·欧拉和雅各布·伯努利的著作。然后他获得了1788年版的约瑟夫·拉格朗日的Mécanique analytiqueⓉ（分析力学），并开始认真研究这部著作。安培写道（再次用第三人称写自己）：-

……阅读[分析力学]使他焕发出新的热情。他重复了其中的所有计算……

然而他的生活很快就被打破了。法国大革命以1789年7月14日攻占巴士底狱开始，但起初对波利米厄地区的影响并不很大。安培的父亲一直平安无事，直到1791年末他接受了里昂治安法官的职位。这个职位使他几乎无法避免麻烦，但家庭遭遇的第一个悲剧是在1792年，安培的姐妹去世了。里昂市拒绝执行巴黎的指令，城市被围困了两个月。城市陷落后，安培的父亲因对后来被处死的雅各宾派骑士发出逮捕令而被捕。安培的父亲以非凡的镇定走向断头台，在狱中给安培的母亲写道：

我希望我的死成为我们所有兄弟之间全面和解的印记；我原谅那些为此欢欣的人，那些挑起此事的人，以及那些下令这样做的人……

父亲的死对安培的打击是毁灭性的。他放弃了Mécanique analytique的研究，有18个月没有回到数学研究。直到他遇到一个女孩朱莉，并深深爱上了她，他才恢复到接近从前的样子。朱莉似乎对安培不太感兴趣：

他没有风度；他笨拙、害羞，表现得不好。

尽管有这种冷淡，他们还是在1797年订婚了，安培决定最好表明自己能谋生，于是开始在里昂教授数学。他于1799年与朱莉结婚，他们的儿子让-雅克于1800年出生。安培继续教授数学，直到1802年被任命为布尔中央学校的物理和化学教授。这对安培来说是一段艰难的时期，因为朱莉在他搬到布尔之前就生病了，把她留在了波利米厄。

安培在布尔格时，花了很多时间教授物理和化学，但他的研究是在数学方面。这项研究使他撰写了一篇关于probability的论文The Mathematical Theory of Games，他于1803年提交给了巴黎科学院。皮埃尔·西蒙·拉普拉斯发现了一个错误，在信中向安培解释了该错误，安培得以纠正，论文重新印刷。事实上，这篇论文被修改了多次，安培不愿称其完成，担心可能需要进一步修改。这项工作之后是1803年关于变分法的一篇论文。

在布尔待了一年后，安培在让·巴蒂斯特·约瑟夫·德朗布尔的推荐下被任命到里昂的中学担任数学职位，搬到了离波利米厄更近的地方。由于妻子健康状况持续恶化，他在里昂的时光变得艰难。在数学上，他继续产出优秀的工作，这次是一篇关于解析几何的有趣论文。像许多其他数学家一样，安培似乎能够专注于他的定理，尽管身边有个人悲剧，而且遗憾的是，在他不幸的一生中，这将是需要他做到的。1803年7月妻子去世后，安培被内疚感所困扰，因为在他们短暂的婚姻中，他大部分时间都与妻子分居。他决定离开里昂去巴黎。霍夫曼在[4]中关于他妻子去世后的感受写道：

他随后的抑郁促使他决定尽早离开里昂，前往巴黎的新环境。后来他会后悔这个决定。他痛苦地怀念那些试图填补朱莉去世留下的情感空虚的里昂朋友们。尽管安培逐渐适应了巴黎科学界的优先权争议和内斗，但他始终渴望回到他在里昂所经历的智识生活。

此时，安培作为数学教师和研究数学家已有相当声誉，凭借这一声誉，他于1804年被任命为巴黎综合理工学院的分析学 répétiteur（基本上是辅导教师）。没有正规教育和正式资格，他的任命令人惊讶，但表明他的潜力在这一阶段得到了认可。他的生活已经包含许多悲剧，并未改善，他陷入了一场灾难性的婚姻。约瑟夫·拉格朗日和让·巴蒂斯特·约瑟夫·德朗布尔参加了他于1806年8月1日与珍妮的婚礼，但在他们女儿于1807年7月6日出生之前，这对夫妇已分居且互不交谈。他们于1808年合法分居，安培获得了他们女儿阿尔比娜的监护权。

1809年被任命为巴黎综合理工学院的数学教授，他在那里任职直到1828年。安培和奥古斯丁·路易·柯西共同教授分析和力学，两者之间有很大对比，奥古斯丁·路易·柯西的严格分析教学带来了巨大的数学进步，但学生发现极其困难，他们更喜欢安培更传统的分析和力学方法。安培于1826年被任命为法兰西大学的讲席，他担任该职位直到去世。

安培在广泛的主题上工作。虽然是数学教授，但他的兴趣除了数学外，还包括形而上学、物理和化学。在数学方面，他研究偏微分方程，产生了一个分类，他于1814年提交给研究所。这似乎是他在1814年11月当选为国家科学研究所成员的关键一步，当时他击败了奥古斯丁·路易·柯西，获得了56票中的28票。

安培也在化学方面做出了重大贡献。1811年，他提出两年前制备的一种无水酸是氢与一种未知元素的化合物，类似于氯，他建议将其命名为氟。在专注于数学以寻求进入研究所后，安培在1814年当选后回到化学，并于1816年产生了元素的分类。

安培还研究光的理论，1815年发表了关于光的折射。到1816年，他强烈主张光的波动理论，同意奥古斯丁·菲涅耳，反对让-巴蒂斯特·毕奥和皮埃尔·西蒙·拉普拉斯主张的微粒理论。奥古斯丁·菲涅耳成为安培的好朋友，并从1822年起寄宿在安培家中，直到1827年去世。

在19世纪20年代初，安培在听说丹麦物理学家Hans Christian Orsted的实验结果后，试图给出电与磁的统一理论。安培提出了电路力定律，并通过假设磁化物质内部存在小闭合电路来处理磁性。

值得评论的是，安培多么迅速地产生了这一理论，他一听说Orsted的实验结果就立刻受到了启发。Orsted的工作于1820年9月4日由弗朗索瓦·阿拉戈在巴黎的科学院上报告，一周后弗朗索瓦·阿拉戈在科学院会议上重复了Orsted的实验。在接下来的几周里，安培向科学院演示了各种磁/电效应，并在9月底之前发现了线性导线之间的电动力。他于1820年11月6日在科学院上讲述了他的电动力相加定律，并在下个月讲述了对称性原理。安培以惊人的速度写下了他向科学院描述的工作，并发表在Annales de Chimie et de Physique上。

在接下来的几年里，安培的工作得到了菲力克斯·瓦利的协助，后者在让安培撰写其成果方面提供了宝贵帮助[4]：-

……从他于1823年初完成的回忆录开始，菲力克斯·瓦利现在做出了更具创造性的贡献。但比他的创造力更有价值的是菲力克斯·瓦利的纪律性和长时间专注于特定问题的能力，这对安培尤其宝贵。有理由推测，如果没有菲力克斯·瓦利的帮助，安培可能永远找不到时间完成将其力定律应用于磁现象所需的详细计算。

安培并不是唯一对弗朗索瓦·阿拉戈关于奥斯特实验的报告迅速做出反应的人。让-巴蒂斯特·毕奥和他的助手菲利克斯·沙伐也迅速进行了实验，并于1820年10月向科学院报告。这导致了让-巴蒂斯特·毕奥-菲利克斯·沙伐定律。当时另一位研究磁学的人是西莫恩·德尼·泊松，他坚持在不涉及电的情况下处理磁学。西莫恩·德尼·泊松已经写了两篇关于电的重要回忆录，并于1826年发表了两篇关于磁学的回忆录。

安培关于电和磁的最重要出版物也于1826年出版。它被称为Memoir on the Mathematical Theory of Electrodynamic Phenomena, Uniquely Deduced from Experience，包含电动力定律的数学推导，并描述了四个实验。詹姆斯·克拉克·麦克斯韦在1879年撰写关于这篇回忆录的文章时说：-

我们几乎无法相信安培真的通过他所描述的那些实验发现了作用定律。我们不禁怀疑——事实上，他自己也告诉我们——他是通过某种他没有向我们展示的过程发现了这一定律，而当他后来构建出完美的证明时，他移除了所有支撑起这一证明的脚手架痕迹。

安培的理论成为19世纪电学和磁学发展的基础。麦可·法拉第于1821年发现了电磁感应，安培最初在1822年认为自己独立发现了这一效应，但后来同意这一发现的全部功劳应归于麦可·法拉第。威廉·韦伯也发展了安培的思想，开尔文和詹姆斯·克拉克·麦克斯韦也是如此。

1826年，安培开始在法兰西学院任教。在这里，他能够教授自己设计的课程，而不是在巴黎综合理工学院，那里的主题是固定的。因此，安培在法兰西学院教授电动力学，这门课程在1826-27年由约瑟夫·刘维尔选修。这是安培第二次教约瑟夫·刘维尔，因为约瑟夫·刘维尔在上一学期选修了安培在巴黎综合理工学院的课程。约瑟夫·刘维尔通过编辑一套从安培讲座中记录的笔记，对安培的电动力学课程做出了重要贡献。

鉴于安培生活中的悲剧，人们或许曾希望他的孩子们能给他带来一些快乐。他的儿子确实作为一位研究西欧语言文化起源的历史学家和语文学家而获得了名声。他于1830年被任命为索邦大学外国文学史讲席。然而他与父亲的关系却很困难。Hofmann在[4]中写道：-

两人都性情多变，常常长时间沉思，随后又会爆发愤怒。安培的家根本不够宽敞，无法让两人长期同住。

安培与女儿的关系更加困难。她于1827年嫁给了拿破仑的一名中尉，但他是个酒鬼，婚姻很快陷入困境。安培的女儿于1830年逃到父亲家中，几天后，安培又允许她的丈夫也住到他那里。这被证明是一个困难的局面，导致了警察介入，也给安培带来了许多不幸。

André-Marie Ampère's father, Jean-Jacques Ampère, was a prosperous man who owned a home in Lyon and a country house in Poleymieux, which is only 10 km from Lyon. Up till André-Marie was seven years old the family spent most of the year in Lyon except the summer months which were spent at Poleymieux. However, in 1782, the home at Poleymieux became their main residence since André-Marie's father wished to spend more time on his son's education. Only a short time in winter was spent at Lyon where André-Marie's father saw to his business interests.

Despite not attending school, André-Marie was to be given an excellent education. He describes this education in autobiographical writings (rather strangely referring to himself in the third person):-

His father, who had never ceased to cultivate Latin and French literature, as well as several branches of science, raised him himself in the country near the city where he was born. He never required him to study anything, but he knew how to inspire in him a desire to know. Before being able to read, the young Ampère's greatest pleasure was to listen to passages from Buffon's natural history.

Ampère read articles from L'Encyclopédie many of which, Arago remarked many years later, he could recite in full in later life. Arago also claims that Ampère read the Encyclopédie starting at volume 1 and reading the articles in alphabetical order. Whether Ampère's later desire for classification in all subjects arose from this education, or whether he enjoyed Buffon and the Encyclopédie because of a natural liking for classifying, is hard to say.

It has been claimed that Ampère had mastered all known mathematics by the age of twelve years but this seems somewhat of an exaggeration since, by Ampère's own account, he did not start to read elementary mathematics books until he was 13 years old. However Ampère was always one to feel very confident in his own abilities and he certainly began to develop his own mathematical ideas very quickly and he began to write a treatise on conic sections. Ampère had no contacts with anyone with any depth of mathematical knowledge so it is not surprising that he felt that his ideas were original.

While still only 13 years old Ampère submitted his first paper to the Académie de Lyon. This work attempted to solve the problem of constructing a line of the same length as an arc of a circle. His method involves the use of infinitesimals but since Ampère had not studied the calculus the paper was not found worthy of publication. Shortly after writing the article Ampère began to read d'Alembert's article on the differential calculus in the Encyclopédie and realised that he must learn more mathematics.

After taking a few lessons in the differential and integral calculus from a monk in Lyon, Ampère began to study works by Euler and Bernoulli. He then acquired a copy of the 1788 edition of Lagrange's Mécanique analytique Ⓣ and began serious study of the work. Ampère writes (again writing about himself in the third person):-

... the reading of [Mécanique analytique] had animated him with a new ardour. He repeated all the calculations in it ...

However his life was soon to be shattered. The French Revolution began with the storming of the Bastille on 14 July 1789 but the effect on the Poleymieux region was not very great at first. Ampère's father kept out of trouble until late in 1791 when he accepted the position of Justice of the Peace in Lyon. This post made it virtually impossible for him to avoid trouble but the first tragedy to hit the family was in 1792 when André-Marie's sister died. The city of Lyon refused to carry out instructions from Paris and the city was besieged for two months. On the fall of the city Ampère's father was arrested for issuing an arrest warrant for the Jacobin Chevalier who had then been put to death. Ampère's father went to the guillotine with remarkable composure writing to Ampère's mother from his cell:-

I desire my death to be the seal of a general reconciliation between all our brothers; I pardon those who rejoice in it, those who provoked it, and those who ordered it....

The effect on Ampère of his father's death was devastating. He gave up his studies of Mécanique analytique and did not return to the study of mathematics for 18 months. He only returned to something like his old self when he met a girl, Julie, whom he fell deeply in love with. Julie seemed less attracted to Ampère:-

He has no manners; he is awkward, shy and presents himself poorly.

Despite this coolness they were engaged to be married in 1797 and Ampère decided he better show that he could earn a living so began tutoring mathematics in Lyon. He married Julie in 1799 and their son Jean-Jacques was born in 1800. Ampère continued tutoring mathematics until 1802 when he was appointed professor of physics and chemistry at Bourg École Centrale. This was a difficult time for Ampère since Julie became ill before he made the move to Bourg leaving her at Poleymieux.

While Ampère was in Bourg he spent much time teaching physics and chemistry but his research was in mathematics. This research resulted in him composing a treatise on probability, The Mathematical Theory of Games, which he submitted to the Paris Academy in 1803. Laplace noticed an error, explaining the error to Ampère in a letter, which Ampère was able to correct and the treatise was reprinted. In fact the treatise was modified a number of times and Ampère was reluctant to call it completed for fear that further changes might be required. This work was followed by one on the calculus of variations in 1803.

After a year in Bourg, Ampère moved closer to Poleymieux being appointed to a mathematics position at the Lycée in Lyon on Delambre's recommendation. His time spent in Lyon had been made difficult due to the continuing decline in his wife's health. Mathematically he continued to produce good work, this time an interesting treatise on analytic geometry. Like a number of other mathematicians, Ampère seemed able to concentrate on his theorems despite the personal tragedy around him and, sadly, this would be required of him throughout his unhappy life. After his wife died in July 1803, Ampère was left with feelings of guilt for he had lived apart from his wife during much of their short marriage. He decided to leave Lyon for Paris. Hofman writes in [4] regarding his feelings following his wife's death:-

His subsequent depression contributed to his decision to take the earliest opportunity to leave Lyon for new surroundings in Paris. Later he would regret this decision. The Lyon friends who attempted to fill the emotional void left by Julie's death were missed painfully. Although Ampère gradually adjusted to the priority disputes and infighting of the Parisian scientific community, he always longed for a return to the intellectual life he experienced in Lyon.

By this time Ampère had a fair reputation as both a teacher of mathematics and as a research mathematician and on the strength of this reputation he was appointed répétiteur (basically a tutor) in analysis at the École Polytechnique in 1804. Without a formal education and formal qualifications his appointment is surprising but shows that his potential was recognised at this stage. His life, already containing many tragedies, did not improve and he embarked on a disastrous marriage. Lagrange and Delambre attended his wedding to Jenny on 1 August 1806 but, before the birth of their daughter on 6 July 1807, the couple were living apart and were not on speaking terms. They were legally separated in 1808 and Ampère was given custody of their daughter Albine.

Appointed professor of mathematics at the École Polytechnique in 1809 he held posts there until 1828. Ampère and Cauchy shared the teaching of analysis and mechanics and there was a great contrast between the two with Cauchy's rigorous analysis teaching leading to great mathematical progress but found extremely difficult by students who greatly preferred Ampère's more conventional approach to analysis and mechanics. Ampère was appointed to a chair at Université de France in 1826 which he held until his death.

In Paris Ampère worked on a wide variety of topics. Although a mathematics professor, his interests included, in addition to mathematics, metaphysics, physics and chemistry. In mathematics he worked on partial differential equations, producing a classification which he presented to the Institut in 1814. This seems to have been a crucial step in his election to the Institut National des Sciences in November 1814 when he defeated Cauchy, receiving 28 of the 56 votes cast.

Ampère was also making significant contributions to chemistry. In 1811 he suggested that an anhydrous acid prepared two years earlier was a compound of hydrogen with an unknown element, analogous to chlorine, for which he suggested the name fluorine. After concentrating on mathematics as he sought admission to the Institut, Ampère returned to chemistry after his election in 1814 and produced a classification of elements in 1816.

Ampère also worked on the theory of light, publishing on refraction of light in 1815. By 1816 he was a strong advocate of a wave theory of light, agreeing with Fresnel and opposed to Biot and Laplace who advocated a corpuscular theory. Fresnel became a good friend of Ampère's and lodged at Ampère's home from 1822 until his death in 1827.

In the early 1820s, Ampère attempted to give a combined theory of electricity and magnetism after hearing about experimental results by the Danish physicist Hans Christian Orsted. Ampère formulated a circuit force law and treated magnetism by postulating small closed circuits inside the magnetised substance.

It is worth commenting on how quickly Ampère produced this theory, the inspiration striking him immediately he heard of Orsted's experimental results. Orsted's work was reported the Academy in Paris on 4 September 1820 by Arago and a week later Arago repeated Orsted's experiment at an Academy meeting. Ampère demonstrated various magnetic / electrical effects to the Academy over the next weeks and he had discovered electrodynamical forces between linear wires before the end of September. He spoke on his law of addition of electrodynamical forces at the Academy on 6 November 1820 and on the symmetry principle in the following month. Ampère wrote up the work he had described to the Academy with remarkable speed and it was published in the Annales de Chimie et de Physique.

Ampère was assisted over the next few years in his work by Felix Savary whose help in getting Ampère to write up his results was invaluable [4]:-

... beginning with the memoir he completed early in 1823, Savary now made much more creative contributions. But more than his creativity, it was Savary's discipline and ability to concentrate at length on specific problems that proved especially valuable to Ampère. There is room to speculate that, without Savary's aid. Ampère might never have found time to complete the detailed calculations required to apply his force law to magnetic phenomena.

However Ampère was not the only one to react quickly to Arago's report of Orsted's experiment. Biot, with his assistant Savart, also quickly conducted experiments and reported to the Academy in October 1820. This led to the Biot-Savart Law. Another who worked on magnetism at this time was Poisson who insisted on treating magnetism without any reference to electricity. Poisson had already written two important memoirs on electricity and he published two on magnetism in 1826.

Ampère's most important publication on electricity and magnetism was also published in 1826. It is called Memoir on the Mathematical Theory of Electrodynamic Phenomena, Uniquely Deduced from Experience and contained a mathematical derivation of the electrodynamic force law and describes four experiments. Maxwell, writing about this Memoir in 1879, says:-

We can scarcely believe that Ampère really discovered the law of action by means of the experiments which he describes. We are led to suspect, what, indeed, he tells us himself, that he discovered the law by some process which he has not shown us, and that when he had afterwards built up a perfect demonstration he removed all traces of the scaffolding by which he had raised it.

Ampère's theory became fundamental for 19th century developments in electricity and magnetism. Faraday discovered electromagnetic induction in 1821 and, after initially believing that he had himself discovered the effect in 1822, Ampère agreed that full credit for the discovery should go to Faraday. Weber also developed Ampère's ideas as did Thomson and Maxwell.

In 1826 Ampère began to teach at the Collège de France. Here he was in a position to teach courses of his own design, rather than at the École Polytechnique were the topics were set down. Ampère therefore taught electrodynamics at the Collège de France and this course was taken by Liouville in 1826-27. This was the second time Ampère had taught Liouville since Liouville had taken Ampère's courses at the École Polytechnique in the previous session. Liouville made an important contribution to Ampère's electrodynamics course by editing a set of notes taken from Ampère's lectures.

Given the tragedy in Ampère's life it might have been hoped that his children would bring him some happiness. His son certainly achieved fame as a historian and philologist who studied the cultural origins of western European languages. He was appointed to a chair of history of foreign literature at the Sorbonne in 1830. However his relationship with his father was difficult. Hofmann in [4] writes:-

Both men were temperamental and subject to long periods of brooding followed by explosive outbursts of anger. Ampère's home simply was not expansive to house both of them for any extended period of time.

Ampère had an even more difficult time with his daughter. She married one of Napoleon's lieutenants in 1827 but he was an alcoholic and the marriage soon was in trouble. Ampère's daughter fled to her father's house in 1830 and, some days later, Ampère allowed her husband to live with him also. This proved a difficult situation, led to police intervention and much unhappiness for Ampère.