埃尔温·薛定谔Erwin Schrödinger

埃尔温·薛定谔 的父亲 Rudolf Schrödinger 经营着一家从他自己的父亲那里继承来的小油毡工厂。薛定谔 的母亲 Emily Bauer 有一半英国血统，这一方家族来自 Leamington Spa，另一半是奥地利血统，她的父亲来自维也纳。

薛定谔几乎同时学习英语和德语，因为家里两种语言都有人说。他没有被送去上小学，而是由一位私人教师在家里授课直到十岁。随后，他于1898年秋季进入Akademisches 文理中学（Gymnasium），这比通常的入学时间要晚，因为他在本应入学的时候在英国度过了一个长假。他后来写到了自己在文理中学的时光：-

我在所有科目上都是好学生，热爱数学和物理，但也喜欢古代语法的严格逻辑，只讨厌死记硬背偶然的日期和事实。在德国诗人中，我尤其喜爱剧作家，但讨厌对他们作品进行迂腐的剖析。

在[16]中，有以下引自薛定谔学校同班同学的一段话：-

特别是在物理学和数学方面，薛定谔有一种理解的天赋，使他无需任何课外作业，就能在课堂上立即直接理解所有材料并加以应用。课后……[我们的教授]可以立即把薛定谔叫到黑板前，给他出题，他都能轻松自如地解出。

薛定谔于1906年从文理中学毕业，并于同年进入维也纳大学。在理论物理方面，他学习了分析力学、偏微分方程在动力学中的应用、eigenvalue问题、詹姆斯·克拉克·麦克斯韦方程和电磁理论、光学、热力学以及统计力学。对薛定谔影响最大的是Fritz Hasenöhrl的理论物理讲座。在数学方面，弗朗茨·梅滕斯教他微积分和代数，威廉·维廷格教他函数论、微分方程和数理统计（他觉得这位讲师并不鼓舞人心）。他还听了Gustav Kohn讲授的射影几何、代数曲线和continuous groups。

1910年5月20日，薛定谔因学位论文On the conduction of electricity on the surface of insulators in moist air获得博士学位。此后，他在要塞炮兵中自愿服兵役。然后，他被任命为维也纳的助理，但相当令人意外的是，是在实验物理而非理论物理方面。他后来说，自己进行实验的经历证明对他的理论工作是一笔无价财富，因为这给了他一个实践性的哲学框架，用来安置他的理论思想。

完成教授资格论文（Habilitation）的工作后，他于1914年9月1日获得学位。委员会在推荐授予他学位时并非一致同意，这表明它并非一项杰出的工作。正如Moore在[8]中所写：-

薛定谔早期的科学工作受到阻碍，因为维也纳缺乏一批一流理论家，他本可以通过每日争论和相互批评来磨砺自己的技能。

1914年，薛定谔发表了第一篇重要论文，发展了路德维希·玻尔兹曼的思想。然而，随着第一次世界大战爆发，薛定谔接到命令，前往意大利边境服役。就研究而言，他的服役时间并没有浪费，因为他继续从事理论工作，从意大利前线的岗位上提交了另一篇论文。1915年，他被调往匈牙利服役，并从那里提交了更多论文供发表。在被送回意大利前线后，薛定谔因在战斗中指挥一个炮兵连的出色表现而受到嘉奖。

1917年春天，薛定谔被送回维也纳，受命教授一门气象学课程。他得以继续研究，正是在此时他发表了他关于quantum theory的首批成果。战争结束后，他继续在维也纳工作。从1918年到1920年，他对色觉理论做出了重大贡献。

薛定谔曾在维也纳研究放射性，证明了放射性衰变的统计性质。他还在固体动力学理论方面做出了重要贡献，研究了晶格的动力学。凭借他的工作，1920年1月他被授予维也纳的副教授职位，但此时他希望与Anny Bertel结婚。他们已于1919年订婚，Anny已来到维也纳担任秘书，月薪超过薛定谔的年收入。随后他被授予副教授职位，但薪水仍不足以养活一个不工作的妻子，因此他拒绝了。

薛定谔转而接受了耶拿的助教职位，这使他得以于1920年3月24日与Anny结婚。在那里仅待了很短时间后，他转到斯图加特的讲席，在那里他与汉斯·赖兴巴赫交好。随后他转到布雷斯劳的讲席，这是他在十八个月内的第三次搬迁。然而不久后他再次搬迁，于1921年底接受了苏黎世的理论物理讲席。在这些辗转于各地之间的岁月里，薛定谔研究了生理光学，特别是他继续了他在色觉理论方面的工作。

赫尔曼·外尔是薛定谔在苏黎世最初几年最亲密的同事，他提供了深厚的数学知识，这些知识对薛定谔的工作大有帮助。苏黎世的学术氛围适合薛定谔，苏黎世也成为他做出最重要贡献的地方。从1921年起，他研究原子结构，然后在1924年开始研究量子统计。此后不久，他读了路易·德布罗意的学位论文，这成为他研究方向的一个转折点，并对他的思想产生了重大影响。1925年11月3日，薛定谔写信给阿尔伯特·爱因斯坦：-

几天前，我怀着极大的兴趣读了路易·德布罗意那篇巧妙的学位论文，我终于弄到了它……

11月16日，在另一封信中，薛定谔写道：-

这些天我一直全神贯注于路易·德布罗意的巧妙理论。它极其令人兴奋，但仍有一些非常严重的困难。

一周后，薛定谔就路易·德布罗意的工作举行了一次讨论会，听众中的一位阿诺·索末菲的学生提出应该有一个波动方程。几周之内，薛定谔就找到了他的波动方程。

1926年，薛定谔在一系列六篇论文中发表了他关于波动力学和广义相对论的开创性工作。在其最一般的形式中，含时的薛定谔方程将封闭量子物理系统的时间演化描述为

$i \hbar \Large\frac{\partial }{\partial t}\normalsize \psi(\textbf {r}, t) = \hat {H} \psi(\textbf {r}, t)$

其中$i$是虚数单位，$\Large\frac{\partial }{\partial t}\normalsize$是对时间的偏微分，$t, \psi$是量子系统的波函数，r和$t$分别是位置向量和时间，而$Ĥ$是表征量子系统总能量的哈密顿算符。

正如薛定谔在这些论文中提出的，波动力学是量子理论的第二种表述，第一种是维尔纳·海森堡提出的矩阵力学。波动力学与矩阵力学这两种表述之间的关系被薛定谔立即理解了，正如他1926年的一篇论文中的这段引文所示：-

在波动力学中，位置和动量坐标的每个函数都可能与一个矩阵相关联，使得这些矩阵在任何情况下都满足马克斯·玻恩和维尔纳·海森堡的形式计算规则。... 波动力学中这个微分方程的自然边值问题的解完全等价于维尔纳·海森堡的代数问题的解。

这项工作确实受到了极大的赞誉。马克斯·普朗克将其描述为：-

... 划时代的工作。

阿尔伯特·爱因斯坦写道：-

... 你工作的想法源于真正的天才...

然后，十天后阿尔伯特·爱因斯坦又写道：-

我相信你在量子条件的表述上取得了决定性的进展……

保罗·埃伦费斯特写道：-

我简直被你的[波方程]理论及其带来的奇妙新观点迷住了。过去两周，我们这个小团体每天都站在黑板前好几个小时，以训练自己掌握所有那些精彩的分支。

The Times中薛定谔讣告的作者写道[3]：-

波动力学的引入……作为薛定谔的丰碑，而且是当之无愧的丰碑。

薛定谔接受了威斯康星大学麦迪逊分校的讲学邀请，于1926年12月离开，以便在1927年1月和2月授课。在他离开之前，他被告知自己是柏林马克斯·普朗克讲席的主要候选人。在麦迪逊做了一系列精彩讲座后，他获得了那里的永久教授职位，但[8]：-

……他完全不为美国的职位所动，并以可能对柏林有承诺为由拒绝了。

接替马克斯·普朗克在柏林理论物理学讲席的候选人名单令人印象深刻。阿诺·索末菲排名第一，其次是薛定谔，马克斯·玻恩为第三选择。当阿诺·索末菲决定不离开慕尼黑时，职位提供给了薛定谔。他前往柏林，于1927年10月1日就职，并在那里成为阿尔伯特·爱因斯坦的同事。

尽管他是天主教徒，薛定谔在1933年决定他不能生活在一个迫害犹太人已成为国家政策的国家。Alexander Lindemann，牛津大学物理系主任，于1933年春天访问德国，试图为一些来自德国的年轻犹太科学家在英国安排职位。他与薛定谔谈论为他的一名助手提供职位，并惊讶地发现薛定谔本人有兴趣离开德国。薛定谔要求提供一名同事，阿瑟·马奇，作为他的助手。

要理解薛定谔对马奇的要求，我们必须稍作离题，评论薛定谔对女性的喜好。他与妻子的关系从未良好，并且在妻子知情的情况下有许多情人。安妮多年来有自己的情人，薛定谔的朋友赫尔曼·外尔。薛定谔要求马奇作为他的助手是因为，当时，他爱上了阿瑟·马奇的妻子希尔德。

许多离开德国的科学家在1933年夏天在南蒂罗尔度过。在这里，希尔德怀上了薛定谔的孩子。1933年11月4日，薛定谔、他的妻子和希尔德·马奇抵达牛津。薛定谔被选为马格达伦学院的会士。他们抵达牛津后不久，薛定谔听说，由于他在波动力学方面的工作，他被授予诺贝尔奖。

1934年春天，薛定谔被邀请到普林斯顿讲学，在那里他获得了永久职位的提供。回到牛津后，他就普林斯顿的工资和养老金条件进行了谈判，但最终没有接受。据认为，他希望与安妮和希尔德一起住在普林斯顿，共同抚养他的孩子，这一事实不被接受。薛定谔公开有两个妻子，即使其中一个嫁给了另一个男人，在牛津也不太受欢迎，但他的女儿露丝·乔治·埃里卡于1934年5月30日在那里出生。

1935年，薛定谔发表了一篇关于The present situation in quantum mechanics的三部分文章，其中出现了他著名的薛定谔猫悖论。这是一个思想实验，其中一只猫在封闭的盒子里根据量子事件是否发生而生存或死亡。悖论在于，两个宇宙，一个有一只死猫，一个有一只活猫，似乎平行存在，直到观察者打开盒子。

1936年，薛定谔获得了苏格兰爱丁堡大学的物理学讲席职位。他本可能接受这个职位，但由于内政部工作许可的长期拖延而未能成行。在等待期间，他收到了格拉茨大学的邀请，于是前往奥地利，在格拉茨度过了1936至1938年。随后，马克斯·玻恩获得了爱丁堡的职位，并迅速接受了。

然而，日益逼近的纳粹威胁再次在奥地利波及薛定谔。在德奥合并之后，德国人占领了格拉茨，并将大学更名为阿道夫·希特勒大学。薛定谔在新纳粹校长的建议下，给大学评议会写了一封信，称他：-

……直到最后都错误地判断了我国家的真正意志和真正命运。我自愿且欣喜地作出这一坦白……

这是一封他将终生后悔的信。大约一年后，他在给阿尔伯特·爱因斯坦的一封信中解释了原因：-

我想保持自由——而若不采取极大的两面手法，就无法做到这一点。

纳粹无法忘记他在1933年逃离柏林时给他们造成的侮辱，1938年8月26日，他因“政治不可靠”被解职。他去咨询维也纳的一位官员，那人告诉他，他必须在工业界找一份工作，而且不允许他去外国。他迅速与Anny一起逃离，这次去了罗马，从那里他以国际联盟主席的身份写信给埃蒙·德·瓦莱拉。埃蒙·德·瓦莱拉提出在都柏林为他安排一份工作，在他试图筹建的新高等研究院里。从罗马，薛定谔回到牛津，在那里他收到了根特大学为期一年的访问教授职位的邀请。

在根特度过一段时间后，薛定谔于1939年秋前往都柏林。在那里，他研究电磁理论和相对论，并开始发表关于统一场论的论文。他关于这个主题的第一篇论文写于1943年。1946年，他就这个主题恢复了与阿尔伯特·爱因斯坦的通信。1947年1月，他相信自己取得了重大突破[8]：-

薛定谔对他的新理论如此着迷，以至于他抛开了谨慎，放弃了任何批判性分析的伪装，尽管他的新理论还几乎没有成形，他还是把它作为划时代的进展提交给了科学院和爱尔兰媒体。

Irish Times第二天刊登了对薛定谔的采访，他在采访中说：-

这就是推广。现在阿尔伯特·爱因斯坦理论仅仅成为一个特例……我相信我是对的，如果我错了，我会显得像个十足的傻瓜。

然而，阿尔伯特·爱因斯坦立刻意识到薛定谔的“新理论”[8]毫无价值：-

[薛定谔]甚至在考虑获得第二次诺贝尔奖的可能性。无论如何，整个事件暴露了判断上的失误，而当他真正读到阿尔伯特·爱因斯坦的评论时，他感到极度沮丧。

阿尔伯特·爱因斯坦立即写信说，他将中断他们关于统一场论的通信。然而，统一场论并不是他在都柏林高等研究院爱德华·斯图迪期间唯一感兴趣的课题。他对希腊科学和哲学的研究总结在Nature and the Greeks（1954年）中，那是他在都柏林期间写的。这一时期写成的另一部重要著作是What is life?（1944年），它推动了生物学的进展。

在个人生活方面，薛定谔在都柏林期间又与两位不同的爱尔兰女性育有两个女儿。他一直留在都柏林，直到1956年退休，随后返回维也纳，写下了他的最后一本书Meine Weltansicht Ⓣ（我的世界观）（1961年），表达了他自己的形而上学观点。

在最后几年里，薛定谔仍然对数学物理感兴趣，并继续研究广义相对论、统一场论和介子物理。

Erwin Schrödinger's father, Rudolf Schrödinger, ran a small linoleum factory which he had inherited from his own father. Erwin's mother, Emily Bauer, was half English, this side of the family coming from Leamington Spa, and half Austrian with her father coming from Vienna.

Schrödinger learnt English and German almost at the same time due to the fact that both were spoken in the household. He was not sent to elementary school, but received lessons at home from a private tutor up to the age of ten. He then entered the Akademisches Gymnasium in the autumn of 1898, rather later than was usual since he spent a long holiday in England around the time he might have entered the school. He wrote later about his time at the Gymnasium:-

I was a good student in all subjects, loved mathematics and physics, but also the strict logic of the ancient grammars, hated only memorising incidental dates and facts. Of the German poets, I loved especially the dramatists, but hated the pedantic dissection of their works.

In [16] there is the following quotation from a student in Schrödinger's class at school:-

Especially in physics and mathematics, Schrödinger had a gift for understanding that allowed him, without any homework, immediately and directly to comprehend all the material during the class hours and to apply it. After the lecture ... it was possible for [our professor] to call Schrödinger immediately to the blackboard and to set him problems, which he solved with playful facility.

Schrödinger graduated from the Akademisches Gymnasium in 1906 and, in that year, entered the University of Vienna. In theoretical physics he studied analytical mechanics, applications of partial differential equations to dynamics, eigenvalue problems, Maxwell's equations and electromagnetic theory, optics, thermodynamics, and statistical mechanics. It was Fritz Hasenöhrl's lectures on theoretical physics which had the greatest influence on Schrödinger. In mathematics he was taught calculus and algebra by Franz Mertens, function theory, differential equations and mathematical statistics by Wilhelm Wirtinger (whom he found uninspiring as a lecturer). He also studied projective geometry, algebraic curves and continuous groups in lectures given by Gustav Kohn.

On 20 May 1910, Schrödinger was awarded his doctorate for the dissertation On the conduction of electricity on the surface of insulators in moist air. After this he undertook voluntary military service in the fortress artillery. Then he was appointed to an assistantship at Vienna but, rather surprisingly, in experimental physics rather than theoretical physics. He later said that his experiences conducting experiments proved an invaluable asset to his theoretical work since it gave him a practical philosophical framework in which to set his theoretical ideas.

Having completed the work for his habilitation, he was awarded the degree on 1 September 1914. That it was not an outstanding piece of work is shown by the fact that the committee was not unanimous in recommending him for the degree. As Moore writes in [8]:-

Schrödinger's early scientific work was inhibited by the absence of a group of first-class theoreticians in Vienna, against whom he could sharpen his skills by daily argument and mutual criticism.

In 1914 Schrödinger's first important paper was published developing ideas of Boltzmann. However, with the outbreak of World War I, Schrödinger received orders to take up duty on the Italian border. His time of active service was not wasted as far as research was concerned, however, for he continued his theoretical work, submitting another paper from his position on the Italian front. In 1915 he was transferred to duty in Hungary and from there he submitted further papers for publication. After being sent back to the Italian front, Schrödinger received a citation for outstanding service commanding a battery during a battle.

In the spring of 1917 Schrödinger was sent back to Vienna and assigned to teach a course in meteorology. He was able to continue research and it was at this time that he published his first results on quantum theory. After the end of the war he continued working at Vienna. From 1918 to 1920 he made substantial contributions to the theory of colour vision.

Schrödinger had worked at Vienna on radioactivity, proving the statistical nature of radioactive decay. He had also made important contributions to the kinetic theory of solids, studying the dynamics of crystal lattices. On the strength of his work he was offered an associate professorship at Vienna in January 1920 but by this time he wished to marry Anny Bertel. They had become engaged in 1919 and Anny had come to work as a secretary in Vienna on a monthly salary which was more than Schrödinger's annual income. Then he was offered an associate professorship, still not at a salary large enough to support a non-working wife, so he declined.

Schrödinger accepted instead an assistantship in Jena and this allowed him to marry Anny on 24 March 1920. After only a short time there, he moved to a chair in Stuttgart where he became friendly with Hans Reichenbach. He then moved to a chair at Breslau, his third move in eighteen months. Soon however he was to move yet again, accepting the chair of theoretical physics in Zürich in late 1921. During these years of changing from one place to another, Schrödinger studied physiological optics, in particular he continued his work on the theory of colour vision.

Weyl was Schrödinger's closest colleague in his first years in Zürich and he was to provide the deep mathematical knowledge which would prove so helpful to Schrödinger in his work. The intellectual atmosphere in Zürich suited Schrödinger and Zürich was to be the place where he made his most important contributions. From 1921 he studied atomic structure, then in 1924 he began to study quantum statistics. Soon after this he read de Broglie's thesis which became a turning point in the direction of his research and had a major influence on his thinking. On 3 November 1925 Schrödinger wrote to Einstein:-

A few days ago I read with great interest the ingenious thesis of Louis de Broglie, which I finally got hold of...

On 16 November, in another letter, Schrödinger wrote:-

I have been intensely concerned these days with Louis de Broglie's ingenious theory. It is extraordinarily exciting, but still has some very grave difficulties.

One week later Schrödinger gave a seminar on de Broglie's work and a member of the audience, a student of Sommerfeld's, suggested that there should be a wave equation. Within a few weeks Schrödinger had found his wave equation.

Schrödinger published his revolutionary work relating to wave mechanics and the general theory of relativity in a series of six papers in 1926. In its most general form, the time-dependent Schrödinger equation describes the time evolution of closed quantum physical systems as

$i \hbar \Large\frac{\partial }{\partial t}\normalsize \psi(\textbf {r}, t) = \hat {H} \psi(\textbf {r}, t)$

where $i$ is the imaginary unit, $\Large\frac{\partial }{\partial t}\normalsize$ is partial differentiation with respect to time $t, \psi$ is the wave function of the quantum system, r and $t$ are the position vector and time respectively, and $Ĥ$ is the Hamiltonian operator characterizing the total energy of the quantum system.

Wave mechanics, as proposed by Schrödinger in these papers, was the second formulation of quantum theory, the first being matrix mechanics due to Heisenberg. The relation between the two formulations of wave mechanics and matrix mechanics was understood by Schrödinger immediately as this quotation from one of his 1926 papers shows:-

To each function of the position- and momentum- coordinates in wave mechanics there may be related a matrix in such a way that these matrices, in every case satisfy the formal calculation rules of Born and Heisenberg. ... The solution of the natural boundary value problem of this differential equation in wave mechanics is completely equivalent to the solution of Heisenberg's algebraic problem.

The work was indeed received with great acclaim. Planck described it as:-

... epoch-making work.

Einstein wrote:-

... the idea of your work springs from true genius...

Then, ten days later Einstein wrote again:-

I am convinced that you have made a decisive advance with your formulation of the quantum condition...

Ehrenfest wrote:-

I am simply fascinated by your [wave equation] theory and the wonderful new viewpoint it brings. Every day for the past two weeks our little group has been standing for hours at a time in front of the blackboard in order to train itself in all the splendid ramifications.

The author of Schrödinger's obituary in The Times wrote [3]:-

The introduction of wave mechanics stands ... as Schrödinger's monument and a worthy one.

Schrödinger accepted an invitation to lecture at the University of Wisconsin, Madison, leaving in December 1926 to give his lectures in January and February 1927. Before he left he was told he was the leading candidate for Planck's chair in Berlin. After giving a brilliant series of lectures in Madison he was offered a permanent professorship there but [8]:-

... he was not at all tempted by an American position, and he declined on the basis of a possible commitment to Berlin.

The list of candidates to succeed Planck in the chair of theoretical physics at Berlin was impressive. Sommerfeld was ranked in first place, followed by Schrödinger, with Born as the third choice. When Sommerfeld decided not to leave Munich, the offer was made to Schrödinger. He went to Berlin, taking up the post on 1 October 1927 and there he became a colleague of Einstein's.

Although he was a Catholic, Schrödinger decided in 1933 that he could not live in a country in which persecution of Jews had become a national policy. Alexander Lindemann, the head of physics at Oxford University, visited Germany in the spring of 1933 to try to arrange positions in England for some young Jewish scientists from Germany. He spoke to Schrödinger about posts for one of his assistants and was surprised to discover that Schrödinger himself was interested in leaving Germany. Schrödinger asked for a colleague, Arthur March, to be offered a post as his assistant.

To understand Schrödinger's request for March we must digress a little and comment on Schrödinger's liking for women. His relations with his wife had never been good and he had had many lovers with his wife's knowledge. Anny had her own lover for many years, Schrödinger's friend Weyl. Schrödinger's request for March to be his assistant was because, at that time, he was in love with Arthur March's wife Hilde.

Many of the scientists who had left Germany spent the summer of 1933 in the South Tyrol. Here Hilde became pregnant with Schrödinger's child. On 4 November 1933 Schrödinger, his wife and Hilde March arrived in Oxford. Schrödinger had been elected a fellow of Magdalen College. Soon after they arrived in Oxford, Schrödinger heard that, for his work on wave mechanics, he had been awarded the Nobel prize.

In the spring of 1934 Schrödinger was invited to lecture at Princeton and while there he was made an offer of a permanent position. On his return to Oxford he negotiated about salary and pension conditions at Princeton but in the end he did not accept. It is thought that the fact that he wished to live at Princeton with Anny and Hilde both sharing the upbringing of his child was not found acceptable. The fact that Schrödinger openly had two wives, even if one of them was married to another man, did not go down too well in Oxford either, but his daughter Ruth Georgie Erica was born there on 30 May 1934.

In 1935 Schrödinger published a three-part essay on The present situation in quantum mechanics in which his famous Schrödinger's cat paradox appears. This was a thought experiment where a cat in a closed box either lived or died according to whether a quantum event occurred. The paradox was that both universes, one with a dead cat and one with a live one, seemed to exist in parallel until an observer opened the box.

In 1936 Schrödinger was offered the chair of physics at the University of Edinburgh in Scotland. He may have accepted that post but for a long delay in obtaining a work permit from the Home Office. While he was waiting he received an offer from the University of Graz and he went to Austria and spent the years 1936-1938 in Graz. Born was then offered the Edinburgh post which he quickly accepted.

However the advancing Nazi threat caught up with Schrödinger again in Austria. After the Anschluss the Germans occupied Graz and renamed the university Adolf Hitler University. Schrödinger wrote a letter to the University Senate, on the advice on the new Nazi rector, saying that he had:-

... misjudged up to the last the true will and the true destiny of my country. I make this confession willingly and joyfully...

It was a letter he was to regret for the rest of his life. He explained the reason to Einstein in a letter written about a year later:-

I wanted to remain free - and could not do so without great duplicity.

The Nazis could not forget the insult he had caused them when he fled from Berlin in 1933 and on 26 August 1938 he was dismissed from his post for 'political unreliability'. He went to consult an official in Vienna who told him that he must get a job in industry and that he would not be allowed to go to a foreign country. He fled quickly with Anny, this time to Rome from where he wrote to de Valera as President of the League of Nations. De Valera offered to arrange a job for him in Dublin in the new Institute for Advanced Studies he was trying to set up. From Rome, Schrödinger went back to Oxford, and there he received an offer of a one year visiting professorship at the University of Gent.

After his time in Gent, Schrödinger went to Dublin in the autumn of 1939. There he studied electromagnetic theory and relativity and began to publish on a unified field theory. His first paper on this topic was written in 1943. In 1946 he renewed his correspondence with Einstein on this topic. In January 1947 he believed he had made a major breakthrough [8]:-

Schrödinger was so entranced by his new theory that he threw caution to the winds, abandoned any pretence of critical analysis, and even though his new theory was scarcely hatched, he presented it to the Academy and to the Irish press as an epoch-making advance.

The Irish Times carried an interview with Schrödinger the next day in which he said:-

This is the generalisation. Now the Einstein Theory becomes simply a special case... I believe I am right, I shall look an awful fool if I am wrong.

Einstein, however, realised immediately that there was nothing of merit in Schrödinger's 'new theory' [8]:-

[Schrödinger] was even thinking of the possibility of receiving a second Nobel prize. In any case, the entire episode reveals a lapse in judgment, and when he actually read Einstein's comment, he was devastated.

Einstein wrote immediately saying that he was breaking off their correspondence on unified field theory. Unified field theory was, however, not the only topic to interest him during his time at the Institute for Advanced Study in Dublin. His study of Greek science and philosophy is summarised in Nature and the Greeks (1954) which he wrote while in Dublin. Another important book written during this period was What is life? (1944) which led to progress in biology.

On the personal side Schrödinger had two further daughters while in Dublin, to two different Irish women. He remained in Dublin until he retired in 1956 when he returned to Vienna and wrote his last book Meine Weltansicht Ⓣ (1961) expressing his own metaphysical outlook.

During his last few years Schrödinger remained interested in mathematical physics and continued to work on general relativity, unified field theory and meson physics.