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Schrodinger was born in Vienna on 1887 and entered the University there to read physics in 1906. He worked there as an assistant from 1910 till his war service and again after the war.
 
Some shorts appointments at Jena, Stuttgart and Breslau led up to his appointment to the chair of theoretical physics in Zurich in 1921. His six papers founding wave mechanics came at the end of his Zurich years, and in 1927 he went to the chair in Berlin, to remain there till the advent of Hitler in 1933.
 
He chose to leave, though his own position could have been secure. He spent a short and rather unhappy time in Oxford, even though 1933 was also the year in which he shared the Nobel prize with Dirac.
 
He was offered a chair in Graz in 1936. Believing that there was no real danger of an Anschluss, he accepted, only to have to leave hastily in 1938 for Rome.
 
In that year he had some preliminary discussions with Eamon de Valera, and in 1940 the Eire Government established the Dublin Institute for Advanced Studies with Schrodinger as Director of the School of Theoretical Physics.
 
Fifteen fruitful years followed, his last five years were spent in his native land, where he died at Alpbach (Tyrol) on 1961.
 
— ''C.W Kilmister (1987) "Schrodinger : Centenary Celebration of a Polymath" Cambridge : Cambridge University Press - page 1.''
 
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Schrodinger was born in Austria in 1887 and was educated in Vienna.
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Switzerland had avoided the horrors of the First World War. There was no hyperinflation. The salary and pension offered were more attractive than those Schrodinger had been receiving at the German universities. At the relatively young age for a full professor, Zurich was an ideal appointment. Even though he was well aware he had not yet made a research contribution at the very top level. This was Schrodinger's opportunity to settle down and produce his great work.
 
=== Arosa ===
As soon as he started at the University of Zurich in October 1921, Schrodinger became ill with a serious bout of bronchitis. Five appointments in five different cities in two and a half years were taking their toll. Tuberculosis was suspected and he needed to move to a high altitude to recuperate. The Schrodingers went to Arosa, a town in the Swiss Alps.
 
In Arosa, Schrodinger wrote two papers that continued his progress with quantum theory. The first was on the quantization of vibrations to calculate the specific heats of solids at high temperatures. The second was on the quantized Bohr orbits of an electron. He mentioned the possible need for the use of complex number in the description of the Bohr orbits.
 
After nine months, Schrodinger was feeling well enough to return to Zurich. As a full professor at the University of Zurich, Schrodinger had to give an inaugural lecture. He chose the title "What is a Natural Law?" In this lecture, he emphasised the statistical nature of matter.
 
=== 4th Solvay Conference ===
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Following his first paper on wave mechanics, and encouraged by the acclaim he had received, Schrodinger went on to publish one new paper on his equation in nearly every month in 1926 until the summer. This was the most intense period for research in his life. In his final paper in the series, Schrodinger proposed a version of his equation in which his wave function depends on time. This paper was his final burst of genius and Schrodinger did not again publish an original paper at this very top level.
 
Later, he worked very energetically to promote his new theory to audiences around the world. In the summer of 1926, he lectured in his old universities of Jena and Stuttgart, and also in Munich and Berlin. The reception to his lecture from the senior scientists in Berlin, including Planck, Einstein, Nernst and von Laue was very favourable. Planck even invited him to a reception in his house.
=== US Tour ===
 
He worked very energetically to promote his new theory to audiences around the world. In the summer of 1926, he lectured in his old universities of Jena and Stuttgart, and also in Munich and Berlin. The reception to his lecture from the senior scientists in Berlin, including Planck, Einstein, Nernst and von Laue was very favourable. Planck even invited him to a reception in his house.
 
Schrodinger also received an invitation from Danish scientist Niels Bohr, who had won the Nobel Prize four years before. Bohr met Schrodinger at Copenhagen railway station in October 1296 and could not leave the lecturer alone for several days in intense discussion of the new theory. The strain was too much for him and he took to his bed in Bohr's house. It was the tradition in those days for the host to invite a distinguished speaker to stay at their own house. Bohr could not resist coming to Schrodinger's bedside to continue the discussion.
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On returning to Berlin, Schrodinger was thrown into a major course of lectures covering several areas of physics but with emphasis on electron theory. He was an eloquent and popular lecturer. At that time in Berlin, there was a remarkable range of lectures that the fortunate students could attend. Planck was still lecturing, Lise Meitner gave a course on nuclear physics, Nernst on experimental physics, Ladenburg on spectroscopy, Fritz London on chemical bonding.
 
=== Extending Schrodinger's Theory ===
In 1926, Fritz London had become aware of Schrodinger's papers. Following Sommerfeld's encouragement and support, he received a grant from the Rockefeller Foundation to work in Zurich with Schrodinger. London arrived in Zurich early in April 1927, when Schrodinger was in the USA. In Zurich, London met Walter Heitler. Just like London, Heitler was also very keen to learn more about Schrodinger's paper and transferred his grant to Zurich.
 
However, Schrodinger's style was to carry out research on his own. In contrast to Sommerfeld and Born, who ran large research groups, Schrodinger was not interested in supervising the research of students or postdoctoral fellows. Almost as soon as Schrodinger returned to Zurich, Schrodinger was making the arrangements to go to Berlin. Both London and Heitler, finding themselves unsupervised in Zurich, decided instead to collaborate together on extending Schrodinger's theory.
 
They chose a key problem in chemistry : the bonding of the hydrogen molecule. They wrote down an approximate form for the wave function of this two-electron system in terms of a product of the hydrogen atom wave functions (orbitals) for the electron centered on each atom. This "valence bond" form of the wave function gave some electron density in the region between the two atoms to produce a chemical bond. After some non-trivial calculations, they were able to compute the strength of this chemical bond.
 
This work was submitted for publication almost exactly one year after the submission of Schrodinger's first paper on wave mechanics. It was the first advance in applying Schrodinger's quantum mechanics to a molecule with more than one electron. It remains a major paper in quantum chemistry.
 
This work also illustrates well how the application of Schrodinger's theory to molecules with more than one electron, which is what made him so famous to the wide scientific world. It was done by others, and not by Schrodinger himself. He was aware of this important developments and took Fritz London as an assistant when he moved from Zurich to Berlin. Later, he also arranged for Heitler to join his Institute for Advanced Studies in Dublin in 1941, where he eventually took over from Schrodinger as Director. Heitler took up Irish citizenship and was elected a Fellow of the Royal Society.
 
When Fritz London took his Rockefeller grant to Berlin with Schrodinger, he found the appointment surprisingly congenial. He discovered that Schrodinger's attitude of not interfering with his research had the big advantage that he could work independently. London's work with Heitler on chemical bonding was becoming well known. They had received major compliments on it from no less than Heisenberg, von Laue and Born. Taking quantum mechanics beyond the hydrogen molecule proved difficult at that time because of the computations involved. Meanwhile, London found he could simplify the calculations using the powerful methods of group theory. This work became influential.
 
London also applied a perturbation theory approach to Schrodinger's wave functions to provide a theoretical framework for the long-range dispersion forces between atoms. These "London forces" are significant for the properties of liquids and gases and even for the structures taken up by biological molecules.
 
Tempting offers to Fritz London came from Born in Gottingen and Sommerfeld in Munich, but he preferred the dynamic scientific scene then prevalent in Berlin, which was at its peak in the late 1920s. He much enjoyed the seminars where the highly promising younger members like himself, Viktor Wisskopf, Max Delbruck, Eugene Wigner and Leo Szilard could present their latest ideas to the great senior physicists present, including Planck, Einstein, Schrodinger, von Laue, and Nernst. With quantum mechanics starting to influence chemistry, researchers such as Michael Polanyi, Lise Meitner and Otto Hahn would also come over from the Kaiser Wilhelm Institute for Chemistry. Afte the seminar, the participants would often adjourn to a local tavern to continue the discussions. Sometimes, the Schrodingers would invite the group back to their apartment for Viennese sausage parties.
 
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"Berlin was the most wonderful and absolutely unique atmosphere for all the scientists. They knew it all and they appreciated it all. One had a bit forgotten the first war, and before the second, so it was absolutely a wonderful time. The theatre was at the height, the music was at the height, and science with all the scientific institutes, the industry. And the most famous colloquium, the Berlin Academy had published lectures which were very famous too. There were lots of friends who came together, not on a special day. It was absolutely a very social life. My husband like it very much indeed. "
 
- Anne Schrodinger
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Another young scientist who came to Zurich to work with Schrodinger was the American Linus Pauling. He had won a Guggenheim grant, which enabled him to come to Europe to learn about the new ideas in quantum mechanics in several centres. He stopped off in Munich to see Sommerfeld, visited Born in Gottingen, and then went to Zurich to learn wave mechanics.
 
Like Heitler and London, Pauling found Schrodinger elusive in Zurich. But he immediately realised the potential of the work of Heitler and London regarding chemical bond. As a chemist, he could see how the Heitler-London valence bond theory could be extended to calculate the structure and properties of many important molecules -- including those of interest in organic chemistry --. In due course, he used this theory to explain the tetrahedral shape of the methane molecule and the strong bonding in aromatic molecules like benzene. His book, "The Nature of the Chemical Bond", brought this research together. Later, he was awarded the Nobel Prize for Chemistry in 1954. Years later, Pauling was also involved with movements to stop nuclear testing. In 1962, he was awarded a second Nobel Prize, this time for Peace.
 
=== Lectures in London ===
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After his visits to London, Cambridge and Oxford, Schrodinger and Anny made their way to Leiden in the Netherlands. There, Paul Ehrenfest, who had taken the Chair of Lorentz, held a lecture series to rival the Kapitsa Club in Cambridge. After a good dinner, Ehrenfest would fire probing questions at the visiting speaker who would be staying in the guest room of his house at 57 Witte Rozenstraat. The speaker would then write their signature on the wall in the hall just outside the guest room. Many of the great theoretical physicists had signed in this way, including Einstein, Planck, Bohr and Dirac. Schrodinger added his signature on 21 March 1928.
 
=== Monte Carlo ===
Being so much in demand for lectures did not enhance Schrodinger's scientific productivity for new publications. He produced few papers of notes during the six years he spent in Berlin. His six-month burst of creativity of 1926 was not to be repeated again. He only published two papers in 1928 with just some reviews and short essays in 1929. It is true his annus mirabilis of 1926 was an almost impossible act to follow, but Schrodinger was reluctant to get into the details of extending his theory of wave mechanics in more practical way achieved by others such as Born, London, Heitler and Pauling. In the very competitive scientific atmosphere of Berlin in the late 1920s, this lack of productivity was getting noticed. For example, Leo Szilard said : "Unfortunately, Schroding is doing too much reading and not writing anything".
 
He did, however, publish a novel idea, in which he compared his Schrodinger equation to the diffusion equation for Brownian motion with an imaginary diffusion coefficient. In the present day, this suggestion has been turned into a very powerful "Diffusion Monte Carlo" algorithm, as the diffusion equatiton can be solved with a simple random walk procedure, which is very easy to apply on modern electronic computers. This approach is enabling the Schrodinger equation to be solved numerically for quite complicated multi-dimensional systems, which are hard to tackle with alternative approaches.
 
=== Academy of Science ===
The Prussian Academy of Sciences was a highly prestigious scientific society based in Berlin. There were just five physicists in the academy in 1929 : Planck, Einstein, von Laue, Warburg and Paschen. Schrodinger was elected that year and was the youngest member aged 42. It was expected that members would write papers for the academy. Schrodinger published two papers in 1930 on Heisenberg's uncertainty relations and on relativistic wave mechanics. The Acadmy would come to play an important role in the political storm that would soon overwhelm German science.
 
In 1931 Schrodinger was delighted to be elected a member of the Royal Irish Academy. He was well aware of the many distinguished mathematicians and theoretical physisicsts who had come from Ireland including George Boole, William Hamilton, Joseph Larmor, George Stokes and Lord Kelvin. Schrodinger equation built on the work of Hamilton. He often found that the distinguished academies he was elected to would be useful to him in his subsequent career.
 
=== World War II ===
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Later, Einstein had a major influence on the British attempts to assist the many refugee scientists who left Germany in the 1930s.
 
=== RefugeMoving to Britain ===
Shortly after the Nazis came to power, the Academic Assistance Council was set up in Britain by several notable people, including Lord Rutherford. This Council over the next few years helped over 2,600 academic refugees to come to Britain. As many as 16 later won Nobel Prizes, 74 became Fellows of the Royal Society, and 34 Fellows of the British Academy. Furthermore, after being rescued by Britain, several of these scientific refugees moved on to the USA.
 
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Schrodinger deposited his 85,000 Swedish Kroner Nobel Prize cheque in a Swedish bank account. This meant that when he later had to leave Austria in a hurry in September 1938, the Nazis were unable to confiscate his prize money, which they did with other Nobel Prize winners who were forced to leave Austria.
 
=== UnhappySchrodinger's Time in OxfordCat ===
While in Oxford, Schrodinger published four papers which have been very influential. These papers extended the debate on the appropriate interpretation of quantum mechanics.
In Berlin, Schrodinger had attended the remarkable seminars in theoretical physics together with world-leading stars such as Einstein, Planck, Nernst, von Laue and with highly promising younger colleagues including Delbruck, Szilard, Wigner and Weisskopf. In Zurich, Schrodinger had also attended seminars together with brilliant ETH professors such as Debye and Weyl. This had inspired him to dream up his equation. But there was no such seminar of this quality at Oxford. Schrodinger's friend, Karl Popper wrote :
 
The first of these papers was submitted to the Mathematical Proceedings of the Cambridge Philosophical Society on 14 August 1935. It was communicated by Max Born. "Communicated" refers to the process by which a scientific paper is submitted to a journal for publication by a third party, who is typically an established member of the academic community. Born acted as a mediator between the author of the paper and the journal. He would have reviewed the paper and deemed it appropriate for publication in the journal, and then submitted it on behalf of the author. In those days, to ensure the integrity of a paper submitted to a journal of a learned society, it needed to be communicated by a member of the society.
 
The paper, written in English, had the title "Discussion of Probability Relations between Separated Systems". It stated :
 
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When two systems, of which we know the states by their respective representatives, enter into temporary physical interaction due to known forces between them, and when after the time of mutual influence the systems separate again, they can no longer be described in the same way as before, viz, by endowing each of them with a representative of its own.
In Oxford I met Schrodinger and had long conversations with him. He was very unhappy in Oxford... In Oxford, he had been very hospitably received. He could not of course expect a seminar of giants, but what he did miss was the passionate interest in theoretical physics, among students and teachers alike.
 
I would not call that "one", but rather "the" characteristic trait of quantum mechanics. The one that enforces its entire departure from classical lines of thought.
 
By the interaction, the two representatives (or ψ-functions) have become entangled. To disentangle them we must gather further information by experiment.
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This problem had become quite well known in quantum chemistry. When two electronic wave functions (orbitals) based on different atoms in a molecule which are placed quite far apart can still be mixed together if there is an interaction between them. The mixing becomes strongers if the two original states have similar energies, even if they are quite far apart in distance.
His wife Anny summarised things rather succinctly
 
This paper has become highly cited in modern times as it is an early work discussing some of the principles behind quantum information processing and quantum computation. It also introduced the word "entangled" into quantum mechanics. The problem expressed in the final sentence above, with regards to disentangling the states in a practical experiment, remains one of the key challenges in quantum computation.
 
The paper referenced one published by Einstein, Podolsky and Rosen, in which it was argued that quantum mechancis provides an incomplete description of physical reality. That paper had considered two interacting particles. If the position of the first particle was measured, under the principles of quantum mechanics, the result of measuring the position of the second particle could be predicted. However, they claimed this was unsatisfactory as no action taken on the first particle could instantaneously influence the other particle, as information would then be transmitted faster than light.
 
Scrodinger then followed up his first paper on entanglement with a second one to the same journal entitled "Probability relations between separated systems". In this case, the paper was communicated to the Cambridge Philosophical Society by Paul Dirac. This paper develops the concept of mixtures of states that had been introduced by John von Neumann. The paper concludes by stating on mixed states that : "These conclusions, unavoidable within the present theory but repugnant to some physiscists including the author, are caused by applying non-relativistic quantum mechanics beyond its legitimate range".
 
The third paper from Schrodinger in Oxford was published on 29 November 1935 in Die Naturwissenschaften, the popular science journal whose editor had been Schrodinger's close friend, Arnold Berliner. In the paper, Schrodinger stated :
 
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A cat is penned in a steel chamber, along with a tiny bit of radioactive substance in a Geiger counter, which must be secured against direct interference by the cat. The radioactive substance is so small that perhaps in the course of the hour one of the atoms decay, but also, with equal probability, perhaps none of the atoms decay. If it decays, the counter tube discharges. Then, through a relay, it releases a hammer which shatters a small flask of hydrocyanic acid.
In Oxford he was not so happy becaue Oxford is no scientific centre. He really was paid for nothing, just because he was Schrodinger. Of course, they gave him a high salary, but he had no duties whatsoever. He couldn't even give a lecture because the lectures are all made out. The scientific centre was Cambridge, of course, and not Oxford. He always called his high salary in Oxford, 'I feel like a charity case.'
 
If one has left this entire system to itself for an hour, one would say that the cat still lives, if meanwhile no atom has decayed.
 
The ψ-function of the entire system would express this by having in it the living and (pardon the expression) dead cat mixed or smeared out in equal parts.
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Because Schrodinger used the example of the life or death of a cat, it has caught the imagination of the public more than any other of his works to the present day. Accordingly, "Schrodinger's Cat states" is also a phrase used by physicists in connection with a microscopic quantum effect having an influence on a macroscopic phenomenon.
There are several other reasons why Schrodinger to find it hard to settle in Oxford. He was an independent and informal character. He did not like traditions, rules and formal dress, which are still prevalent in Oxford. He was a lone scientist and not a collaborator. Furthermore, as a Nobel Prize winner, he was at once distracted by many invitations to visit departments overseas. The emphasis at Oxford was also very much teaching and lectures to undergraduates followed up by written examniations. Schrodinger was not used to teaching in this way and preferred high-level lectures on the latest research.
 
=== MarchBack to Austria ===
Schrodinger visited Austria in 1935 to give his guest lectures in Vienna. He also visited Graz where his old friend Kohlrausch was based. The possibility of a post there was discussed further. After returning to Oxford, he wrote to Hans Thirring on 1936:
The ICI financial support was also used to bring Arthur March to Oxford on leave from Innsbruck. March retained a junior professorial position at the University of Innsbruck, but he would need extra funds to live in Oxford. The justification for funding March was that he would collaborate with Schrodinger on a book on wave mechanics and would do research relevant to the interest of ICI.
 
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In his three-year period in Oxford from 1933 - 1936 March did not have a college position and also did not have a formal position in the Physics Department. He did publish one scientific paper in 1935 in the "Transactions of the Faraday Society". This paper, written in English, describes the forces between colloidal particles. This area of research was of commercial interest to ICI. He did not provide an institution or address with his paper. This may have been intentional due to the ambiguity of his position at the time. At the end of his paper, he did express the acknowledgement : "I have much pleasure in thanking the Imperial Chemical Industries, whose generosity enabled me to carry out this investigation.
In the last four weeks (and more) I have let the Austrian affair go through my head and I regretted that after the visit to Graz and the second conversation in the Ministry I could no longer talk to you in a frank manner.
 
The following dream has now developed for me. Couldn't you get people around to turn the professorship in Graz into something that plays between Graz and Vienna? I don't want to officially accept a full teaching commitment in Graz, but would like to do a small amount also in Vienna.
When March returned to Innsbruck in 1936 with his family, he did not publish again on colloids, reverting to his more fundamental theoretical work. He stayed in Innsbruck for the rest for his career, leading a department in theoretical physics.
 
I would like to go back. I felt so warm and at home in Austria during the weeks I was there.
=== Offer from US ===
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Following the confirmation in 1919 of his General Theory of Relativity in astronomical observations by the Cambridge astrophysicist Arthur Eddington, Einstein had become a scientific superstar known the world over. His informal appearance and regular comments to the press added to his fame. Lindemann had arranged funding from the Rhodes Trust to support a visit by Einstein in May 1931 collected him from a boat arriving at Southampton docks. His chauffeur drove Einstein to Oxford. Einstein stayed for nearly one month and gave a lecture to a packed Rhodes House of over 500 students and faculty. After returning to Berlin, Einstein did write a letter of thanks to Lindemann emphasising "the wonderful weeks he had spent in Oxford".
 
By the spring of 1936, Schrodinger was having detailed negotiations with the federal authorities about a position back in Austria. And finally by the summer of 1936, Schrodinger had settled the arrangements for a Chair at the University of Graz and an Honorary Professorship at the University of Vienna.
However, in the 1931, the political situation in Germany was changing rapidly. Encouraged by the success of the visit, the huge publicity it received, and the emerging problems in Germany, Lindemann managed to persuade his colleagues in Christ Church to offer Einstein a Studentship with a stipend of £400 per annum, a dining allowance and a set of rooms for five years. The condition associated with this offer was that Einstein would spend a month each year in Oxford.
=== Anschluss ===
Schrodinger had been working away from Austria for 16 years when he returned in 1936. His home country had seen many changes during this period.
 
When he left Vienna to go to Jena in Germany with his new bride Anny in 1920, the Austro-Hungarian Empire had collapsed just two years before. A provisional assembly had drafted a constitution. Over 98% of the population in the border regions of the Tyrol and Salzburg were in favour of unification of Austria with Germany. But the Treaties of Versailles and Saint-Germain, signed by the victorious allies in 1919, forbade this Anschluss unification. Nevertheless, the first constitutions of the Weimer Repulic and the First Austrian Republic expressed a political goal for unification.
Meanwhile, Einstein was also having discussions with the California Institute of Technology on a similar visiting position, but Oxford was much closer to his home at that time. Einstein returned again to Oxford in May 1932 and gave the lecture. However, while in Oxford, Einstein had a visit from Abraham Flexner, the Director of the newly created Institute for Advanced Study (IAS) in Princeton, USA. Flexner raised the possibility of Einstein moving permanently to his Institute with a very high salary. By 1933, with the situation getting much more difficult back in Berlin with even his life under threat, Einstein gladly accepted this offer. Once Einstein had started at Princeton with his exceptional salary of $16,000 a year and an atmosphere of safety compared to the developing turmoil in Europe, he wrote to Lindemann saying he would be unable to continue to visit Christ Church.
 
In the 1920s, Austria and Germany both suffered severe economic problem which was exacerbated by the worldwide financial crash at the end of the decade. There were many political parties and changes of government. The ties of the more powerful Germany with Austria remained strong, particularly with the need for minerals and skilled labour. Hitler was born in Austria and his National Socialist Party had the firm aim of reuniting all Germans who lived in the countries neighbouring Germany. He had written in Mein Kampf that he wished to create a union between Austria and Germany.
 
The Christian Socialist Party, the dominant party in Austria in the late 1920s, did not favour an Anschluss or association with the Nazis. After Hitler was made Chancellor of Germany in 1933, there was considerable unrest in Austria from the Nazi groups there. There was civil war in 1934 and all political parties, except the Christian Socialist, were banned. Engelbert Dollfuss, the Cancellor of Austria, was assassinated by Austrian Nazis in an attempted coup in 1934. He was replaced by Kurt Schuschnigg, who was anti-Hitler.
 
By the summer of 1936, it seemed obvious to many observers that the political situation in Austria was rapidly deteriorating but Schrodinger failed to realise this. It seems that his friend Hans Thirring, who largely responsible for bringing him back to Austria, was not fully aware of this either. Schrodinger wife Any commented :
 
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It never occured to us that this step might turn out to be rather foolish, even dangerous. Many of our friends shook their heads and soon we understood their attitudes.
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Two years later, on January 1938, the headquarters of the Austrian National Socialist Party in Vienna was raided by the Austrian police who discovered a huge cache of arms and plans for a putsch.
 
Later, on 12 February 1938, Schusnigg, the Chancellor of Austria, had met with Hitler in his residence at Berchtesgaden. Hitler proposed that Nazi sympathiser be appointed to positions in the Austrian Government. This included making Arthur Seyss-Inquart the Minister of Public Security, which could control the police. In return, Hitler said the would affirm his support for Austrian sovereignty.
 
Chancellor Schuschnigg called a referendum on 9 March proposing to keep Austria independent of Germany. Hitler was furious and insisted that the referendum must be cancelled. Under much pressure of an invasion, Schuschnigg agreed on the cancellation. Hitler then demanded Schuschnigg's resignation and replacement by Seyss-Inquart.
 
Then, on 12 March 1938, German troops entered Austria and were greeted by jubilant crowds with Nazi salutes and flags. Seyss-Inquart, now the Chancellor, signed an act making Austria a province of Germany. Hitler himself then entered Austria. He went first to his birthplace of Braunau am Inn and then on to Linz, the town of his boyhood. After this, he went to Vienna. In front of a jubilant crowd of 200,000 in the Heldenplatz, he said : "The oldest eastern province of the German province, shall be, from this point on, the newest bastion of the German Reich". Heinrich Himmler and Reinhard Heydrich entered Austria with members of the SS and arrested several prominent politicians, political dissenters and Jewish citizen. Three weeks later Hitler returned again to Austria. He visited Graz on April 4. On the same day, the New York Times reported on his visit : "This Styrian Nazi stronghold (Graz) gave Chancellor Adolf Hitler a reception today that surpassed even his triumphal entry into Vienna a fortnight ago. The hurricane of "Heils" that greeted his arrival was the final outlet of the Styrian longing for unification with Germany".
 
The Magdalen Fellow in Politics, William Mackenzie, was travelling in Austria just after the Anschluss. At the suggestion of President Gordon, he managed to arrange a meeting with Schrodinger and Anny. Mackenzie wrote to Lindemann on 21 April 1938 :
 
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I was staying at the Seekarhaus in the Radstadter Tauern and took the chance of sending a postcard to Mrs. Schrodinger at Graz. I was rather surprised to get a phone call last Tuesday, the 12th, to say that they had just arrived at the nearest hotel, a couple of miles or so from the Seekarhaus. They both came up to lunch next day, the 15th, and were with me most of the afternoon. We had a very long talk about things in general.
 
Schrodinger himself is in good health, has not at any time been under arrest and has not been personally molested. His correspondence, however, is probably being tempered with. No letter from him is to be taken at its face value. Anything sent to him should be as colourless as possible.
 
The University had been shut since the disturbances in February. After the Nazis took over, several of the professors were arrested. The University reopens this week, but Schrodinger's personal position is one of complete uncertainty. He summed it up by saying that they ought logically either promote him to a better job, or put him in a concentration camp. He had no idea which it would be and he doesn't know who is responsible for deciding his fate. Nor what his attitude to the regime is supposed to be. Nor whether he is debarred completely from leaving the country. At least, for the present, he certainly cannot come to Oxford to lecture without specific authorisation from some high power. He doesn't even know whether he needs permission to travel to Berlin.
 
In regard to future plans, he would on the whole like to make his peace with the regime if they will let him. So that his policy is to establish a reputation as a non-political person.
 
We had four or five hours of talk. Naturally, there was a great deal more than this said, but I think these are the main points.
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Lindemann wrote back to thank Mackenzie on 22 April 1938. He had an additional worrying query about a letter from Schrodinger published in the German papers. Lindemann was referring to a letter that had been published under Schrodinger's name on 30 March 1938. The local newspaper, the Grazer Tagespost, gave the letter the headline "Acclamation of the Fuhrer : A Leading Scientist offers himself for the Service of Nation and Fatherland". His scientific colleagues in Europe and America felt particularly let down by the statement. Some of his former colleagues and associates never forgave him. He also had to do a lot of explaining with close friends, including Einstein, Born and Dirac, when he met or corresponded with them personally in the years to come. Later, he wrote to Einstein with an explanation : "I hope you did not seriously denounce my subsequent, certainly quite cowardly, behaviour. I wanted to stay free. I couldn't do it without gross hypocrisy".
 
The German Consulate in Graz had also seen Schrodinger's public statement seeming to support Hitler. They had forwarded it to the Department of Foreign Affairs in Berlin. The response came that : "The question of withdrawing his Professorship might still be addressed by the local administration". Finally, Schrodinger received a leater from the dean of University of Vienna :
 
<blockquote>
On the basis of the decree of the Austrian Ministry of Education of 22 April 1938, No 12474/I/1b, your authorisation to participate in instruction in the Philosophical Faculty of the University of Vienna is withdrawn. You are, therefore, to refrain from any professorial or other duties falling on you within the scope of your former appointment or especially assigned to you.
</blockquote>
 
Following Schrodinger's dismissal from the University of Vienna, it would not be long before the same occured from the University of Graz. On 26 August 1938, the Ministry of Education in Vienna wrote :
 
<blockquote>
On the basis of Sect 4. Paragraph 1 of the ordinance for renovation of the Austrian civil service of 31 May 1938, RGBI.I S. 607, you are dismissed. The dismissal is effective as of the day of arrival of this notice. You have no right to any legal recourse against this dimissal.
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=== Escape from Austria ===
The formal description of the ordinance was "the retirement or dismissal of politically unreliable civil servants." For the first time, the alarm bells were truly ringing in the ears of Schrodinger and Anny. Anny described what happened next.
 
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When the Nazis came to Austria, my husband got several invitations to foreign countries.
 
He was not allowed to get the telegrams himself. They were brought to the university. He was called to the university and he was told : "Of course, you have to refuse. You can't go to Brussels or so." So it was really absolutely like a prison.
 
Only through de Valera we were secured. He knew that we were in danger. But it was absolutely sure he could not write to my husband because everything was censored. So he asked Whittaker to ask born. Born wrote to our friend Professor Richard Bar in Zurich. He told a Dutchman, who then came to Vienna. He came to my mother and told her this important thing. He wrote down in just a few lines that de Valera wanted to create an Institute for Advanced Study and whether he would come, in principle. My mother sent this little piece of paper to Graz. We saw it, we read it three times, and then destroyed it, put it into the fire, and told nobody about it at all.
 
Later, I went with my car with Thirring as far as Munich. I went to Switzerland to Constance. I met our friends there and I told them : "Yes, in principle, he will come. But nothing should be done that will let anybody know that we are going away." My friends wrote that to Born, Born told Whittaker, Whittaker told de Valera.
 
My husband never spoke to de Valera. He Never knew de Valera. Nothing at all. But when this missive came, he was perfectly sure that he must leave Austria at once.
</blockquote>
 
Eamon de Valera was a prominent Irish politician who had been a commander in the 1916 Dublin Easter Rising. He had been the Taoiseach (Head of Government) of Ireland since 1937. He had graduated from the Royal University of Ireland and taught mathematics at several schools. He had heard about the Institute for Advanced Study in Princeton. He was impressed by the recruitment there of Einstein and Weyl. With the distinguished refugees leaving Germany and Austria in large numbers, he had the vision of creating a similar Institute for Advanced Studies in Ireland through recruitment at the top level.
 
Sir Edmund Whittaker, who Schrodinger had met one year before in Rome when they were made founding members of the Pontifical Academy of Science, was a close friend and advisor to de Valera. He had discussed the idea of the Institute for Advanced Studies in detail with de Valera and was a good choice to act as a go-between from De Valera to Max Born and other quiet and careful contacts.
 
<blockquote>
So in three days we packed everything. Three suitcases, we had nothing more. We left everything in Graz behind, took a return ticket to Rome, because everybody knew us in Graz. We didn't dare to take a taxi, so that they knew what we have got with us. With my car I brought the luggage to the station, and then I brought it back to the garage, and I said that they should wash the car. I never saw the car at all again of course. I never saw the other things either because they were confiscated. And with ten marks in our pocket, we left Graz.
</blockquote>
 
Schrodinger had to leave all of his personal documents behind when he fled from Austria. This included his Nobel and Max Planck gold medals. They left Graz on 14 September 1938, taking the day-long train ride to Rome. At that time, it was possible to cross the border from Austria to Italy without a visa. Once the Schrodingers arrived in Rome, they headed for the Vatican, where Schrodinger had been received at the Pontifical Academy of Science.
 
<blockquote>
We didn't have the money to pay the porter in Rome. There Fermi told us : "Don't write from Rome because it is already dangerous. It might be censored."
 
From Vatican City, where the Papal Academy is situated, my husband wrote three letters. One was to Lindemann to tell him that we left Graz. One to our friends in Zurich to get us some money, because we had to borrow money from Fermi. The third one to de Valera, who was the President of the League of Nations at that time. That was a Saturday when we posted the letters in Vatican City.
 
On Monday morning we went again to the Academy. After half an hour's time, came a servant who told us that his excellency was wanted at the telephone. The Irish envoy was at telephone and he said de Valera rang up this morning from Geneva. He told him to do everything for us to bring us as soon as possible into Geneva. We should be at the legation in the afternoon and there de Valera would phone.
 
So, we were there. This was the first time my husband heard de Valera speaking. He said that he was glad that we were out of Austria. He also said that we should come to Geneva to discuss a few things. But as soon as possible, we should go to England or Ireland, because there was such a great danger of war in 1938. The Munich Conference, you know.
</blockquote>
 
The Munich conference was going to be held at the end of September 1938. It involved the leaders of Britain and France, meeting with Hitler and Mussolini. The question was the transfer of the German-speaking Sudeten part of Czechoslovakia to Germany. After much discussion, the transfer was agreed with an international commission to consider the future of other disputed areas. On his return, the British PM Chamberlain famously announced, "Peace for our time." Lord Halifax, who did not go with Chamberlain to Germany, informed the House of Lords that the agreement made was a "lesser of two evils".
 
Anny continued the description of their movements
 
<blockquote>
So de Valera tried to get everything ready for us. We couldn't take any money out of Italy, but he gave us a pound each and gave us first class tickets and off we went. I was quite happy already. I felt already safe, but my husband didn't feel safe at all.
 
In Domodossola they looked at our passports and the luggage. They hardly looked at the luggage at all, but the passports were all right. Then, before we came to Iselle, a carabinieri came into our compartment. He had a piece of paper with our name written on it and we had to leave the compartment with all our luggage. They had looked at our passports. We already had visas for all of Europe because de Valera had said that if we can't go through France, we must go through Spain or Portugal or something.
 
Then, we were asked if we had some money. We said that we had one pound. They thought that we had to smuggle something, because one can't go through Europe on one pound.
</blockquote>
 
Finally, after another 24-hour train trip, they arrived in Geneva. Schrodinger met with de Valera. Then, they stayed for three days in his hotel and then rode on.
 
<blockquote>
There was a blackout in Switzerland. On the other side of the Rhine, one could see the bright lights of Germany.
 
Trains were overflowing and greatly delayed. In France we passed airports with countless airplanes standing ready. All bridges and tunnels were under military guard.
 
In England in Hyde Park, bomb shelters were being feverishly prepared. Anti-aircraft guns pointed to the sky. Everyone had gas masks. In Paddington, we heard reports about the Four Power Conference in Munich. That day, 80,000 children were evacuated.
 
On the 28 September 1938, we reached Oxford.
</blockquote>
 
It was becoming clear that, due to his letter seemingly supporting the Fuhrer, Schrodinger was not nearly as welcome in Oxford as he had been. The Schrodingers were fortunate to be able to stay in the spacious house of J.H.C Whitehead. Whitehead and Schrodinger had run their joint seminar in Oxford some three years before and had become good friends.
 
Following his flight from Austria and Italy, Schrodinger had no personal resources except his Nobel money in Sweden. That was not even readily available. With just the small grant from Magdalen to live on in Oxford, the Schrodingers were living almost hand to mouth. However, de Valera remained very enthusiastic and provided funds for Schrodinger to travel to Dublin to meet him.
 
There, De Valera explained that it would take about a year to get the legislation passed through the Irish Parliament to set up the Institute for Advanced Studies. De Valera also had an interest in Celtic Studies. He constructed an Act to "make provision for the establishment and maintenance in Dublin of an Institute for Advanced Studies, consisting a School of Celtic Studies and a School of Theoretical Physics". The strange mix of Celtic Studies and Theoretical Physics was to produce some criticism from the opposition members in the Irish Parliament that would delay the passing of the Act.
 
Things were now very uncertain for Schrodinger and Anny. However, as has frequently been the case in Schrodinger's story when he was unsure about his future, he then received a very welcome letter. This was from the Fondation Francqui in Belgium offering him a Visiting Professorship at the University of Ghent. He at once accepted. As was often his method to announce the next move in his career, Schrodinger arranged for Nature on 31 December 1938 to report :
 
<blockquote>
Professor Erwin Schrodinger has been appointed by the Fondation Francqui as a Visiting Professor for the next six months to a "Chaire Francqui" in the University of Ghent. His address is Laboratory of Physics, Plateaustraat 22, Gand, Belgium.
</blockquote>
 
=== Moving to Ireland ===
The summer of 1939 was a very tense time for the whole of Europe. Schrodinger was waiting more and more anxiously for the call to come to Dublin. On 1 September, German troops invaded Poland and on 3 September Britain and France declared war on Germany. At that time, Belgium was remaining neutral, but it was very vulnerable and had a border with Germany. Schrodinger still had German nationality that once caused a difficulty with the authorities in Belgium. With the announcement of war, de Valera realised he had to act very quickly. He informed Schrodinger he should come to Dublin as soon as possible, even though his Institute for Advanced Studies had not yet been approved by the Irish Parliament. A temporary professorship was being arranged for him.
 
De Valera's promise to assist with travel permits and visas came through. Schrodinger left Belgium on 4 October 1939. First taking a ferry from Ostend to Dover. After arriving in England, the Schrodinger party then travelled to London, leaving from there at 9 pm to Liverpool, going on to Holyhead in Wales and then taking another boat at 4 am to Dublin.
 
Upon his arrival in Ireland, Schrodinger was being funded on a temporary basis by University College Dublin and the Royal Irish Academy. Irish politics, was volatile. De Valera could easily have lost his position of Taoiseach and his proposed Institute for Advanced Studies. Nevertheless, Schrodinger's reception in Dublin was much more enthusiastic than he had been the case in Oxford. In Dublin, he was an academic superstar who was head and shoulders above other academics in the country in terms of his international repuation.
 
He had developed a popular style of lecturing in almost perfect English and in general terms with no mathematics. He was invited to give many public lectures which were enthusiastically received, advertised and reported in the national Irish press. The Irish Independent on 4 November 1939 reported :
 
<blockquote>
Prof. Erwin Schrodinger, Nobel Prize Winner who formerly held an academic chair in Vienna and was just dismissed from his post by the Nazis, began a course of lectures on the latest form of the Quantum Theory at University College Dublin, yesterday.
 
The lecturer paid a tribute to the work of the late Sir William Rowan Hamilton, Astronomer Royal and former President of the Royal Irish Academy. He had been deeply impressed by his work, he said, long before he had come to Ireland.
</blockquote>
 
By 1940, the German army had invaded Belgium, the Netherlands and Denmark. Chamberlain had resigned and Winston Churchill had become Prime Minister of Great Britain. The situation was getting critical just over the Irish Sea. Meanwhile, the bill to create the Dublin Institute for Advanced Studies was finally passed by the Irish Parliament on 19 June 1940. The first appointment to be made was Professor Erwin Schrodinger as Senior Professor in the School of Physics. He was also appointed to the Council of the Institute for Advanced Studies. So finally Schrodinger had his permanent appointment in a safe place away from the war ravaging close by in Europe. The annual salary was £1,200. This allowed him to cover the living expenses for himself and his family in reasonable comfort.
With the dramatic advances in theoretical physics in Europe, the leaders of American universities were very keen to make appointments in this field of research. In the 1930s American universities were expanding and wanted urgently to become internationally competitive in the sciences. It was realised that with the mass exodus of the leading theoretical physicist from Germany a significant opportunity was arising. In 1934, the University of Princeton felt it had to keep up with its Ivy League competitors and appoint a famous expert in quantum mechanics. In typical American style they decided to go straight to the top. Luther Eisenhart, the Dean of the Graduate School, had named Heisenberg and Schrodinger as the leading candidates. Schrodinger was invited by Dean Eisenhart to visit Princeton to give some lectures for a month. He left England on 8 March 1934 on the ship President Harling. On 29 March 1934 Schrodinger wrote from Princeton to Lindemann on the possibility of Einstein returning again to Oxford, which is a definite no. He also added some news regarding an offer from Princeton.
 
After a succession of nine moves in 20 years with appointments in Jena, Stuttgart, Breslau, Zurich, Berlin, Oxford, Graz, Ghent and Dublin, he did not anticipate that he would be living in Ireland for as long as 17 years. During his 17 years in Ireland, Schrodinger was hugely popular with the public and with the press. As time moved on, he chose more and more general title for his public lectures such as "What is Life", "Science at Play", and "Fun in Science". They were sell-outs. He had become the public face of science in Ireland. Every new prize, election to an academy, new appointment or Honorary Degree, was reported in complementary terms in the "Irish Press".
Shortly after Schrodinger's visit, Paul Dirac was invited for a whole year to the Institute for Advanced Study at Princeton with a generous stipend. There was the hope that he would be able to interact closely with Albert Einstein. However, their characters and ways of working did not mix well. Dirac spent the time writing his definitive book "The Principles of Quantum Mechanics"
 
De Valera himself had founded the "Irish Press" newspaper, which always reported very positively on the Taoiseach and his colleagues. Accordingly, Schrodinger was regularly asked by the Irish Press to comment on almost any subject. Even when he went on cycling holidays, it was reported in the press. It seems that any movement he made or any comment he expressed was reported. There were non-sensational reports on his life at home with his family with no difficult questions asked. After the Second World War, he was also in regular demand to speak on highly serious topics such as the nuclear bomb, or how to deal with German or Austrian Nazis.
Later, Schrodinger then wrote to Flexner, Director of the Institute for Advance Study, on 25 June 1934, from Oxford, telling that he could not accept the offer of the professorship offered to him by the University of Princeton.
 
== Wave Mechanics ==