From 1922 until his retirement in 1952 Nathan Agmon worked in the central office of the Jewish National Fund in Jerusalem, directing its Youth and Information Departments. His early writings in Palestine described life in collective agricultural settlements.

He was best known for his dramatic works, many of which dealt with Jewish history and such controversial personalities as Judas Iscariot and Shabtai Tzvi. He also published books on South American Jewry and Zionism.

... to make the world a better place by educational activities, to be aware of injustice, to feel responsible for society's future and to volunteer in their community.

Since the Hebrew University's buildings are still occupied by Abdulla's Arab Legion, its 1,000 students are dispersed in seventeen buildings all over Jerusalem. At the University each student elects a specific program which is subject only to very general limitations. Usually only one yearly examination is given in each subject. A very general examination is given after four or five years' study before a master's degree is awarded. This examination may be taken whenever a student is ready for it and work may be completed at the student's own speed. At the Hebrew University all subjects including the sciences are taught in Hebrew.

The author announces a very general theorem, too complicated to reproduce here, giving an estimate for a function which is of exponential type in an angle and of prescribed growth on a sequence of points in the angle. A consequence is a similarly general estimate for the partial sums of the power series of a function with coefficients of prescribed growth.

If a power series has an infinity of gaps of length k, with a bounded distance between consecutive gaps, then it has at least k+1 singular points on the circle of convergence. The proof is outlined and a more general theorem is stated.

It should also be noted that some of the results obtained here were stated by us, in the case of Taylor series, in four Notes in Comptes rendus.

I express my sincere gratitude to M Mandelbrojt, who kindly took an interest in my work, allowing me to come and present it in Paris. I can never express my gratitude enough for his insightful advice and warm friendship.

I also want to thank M Denjoy for his kind introduction and M Montel for the trust he showed in me. I was infinitely touched by the excellent welcome I received from M Valiron and M Favard.

I cannot conclude without taking this opportunity to express my sincere gratitude to my Masters of Jerusalem, M Fekete and M Amira, whose encouragement has always been so invaluable to me.

Mandelbrojt taught at Rice in 1926, then returned to campus for a good part of World War II. His time here was incredibly productive. He taught both graduate students and undergraduates, gave lecture series which were later published, and was the speaker at every Math Department colloquium for the next four years. After the war ended he spent every spring semester at Rice for twenty years. It was on Mandelbrojt's advice that President Houston hired Agmon.

Dear Dr Houston: Thank you for your letter of 5 March 1949 informing me of my appointment as Lecturer in Mathematics at the Rice Institute for the coming academic year. It will be a great honour for me to lecture in your very distinguished university and I shall do my best to prove myself worthy of the confidence shown in me. Thank you, too, for the very kind suggestions regarding arrangements for travelling and living accommodation. I shall carry them out as you have indicated. I look forward with great pleasure to working with the Rice Institute.

Dr Agmon, who thinks that Rice is "a very nice place," was impressed by the Fondren Library. "The people here are very hospitable, very kind, and always helpful," he said. Dr Agmon is interested in music, swimming, and chess. He was once the youth chess champion in Israel.

Mrs Agmon holds a degree from Columbia and was formerly editor of an Israeli weekly. Dr Agmon's father, Nathan Bistrizky, is a well-known Zionist worker and writer. He has published novels and articles, and has had many of his plays produced in Israel.

This semester Dr Agmon will teach Math. 560 (Infinitely Differentiable Functions), a Math 300 section and a seminar.

Professor Shmuel Agmon is an outstanding Israeli mathematician who made fundamental contributions to analysis and partial differential equations. These contributions include highlights such as the general theory of elliptic boundary value problems (in collaboration with L Nirenberg and A Douglis), Agmon's method for proving exponential decay of eigenfunctions for elliptic operators, and spectral and scattering theory of Schrödinger operators.

Based on notes from a summer course in 1963, this book gives a very clear and thorough introduction to the theory. Many results of fundamental importance for the subject are here presented in a readily accessible form, often for the first time with detailed proofs and under minimal assumptions.

The first part deals with the existence of solutions to the Dirichlet problem for an elliptic equation of any order, and with differentiability properties of the solutions of elliptic equations. These two different topics are dealt with by the same tools of a priori estimates, weak derivatives, etc. After giving some results on general coerciveness and some special boundary conditions (other than the Dirichlet conditions), the author proceeds to solve eigenvalue problems in a setting which is applicable to general boundary conditions, both for self-adjoint and non-self-adjoint elliptic operators. The asymptotic behaviour of the eigenvalues and expansion theorems are derived. This treatment of the eigenvalue problem is an original contribution of the author.

The book under review is hard analysis with a vengeance (so those who, as a matter of principle, find connections with physicist's ways of doing things off-putting need not worry) and is in fact pitched at a rather high level. Of course the latter judgment on my part reflects the fact that no one would confuse me for a hard analyst: a monograph such as the present one, with inequalities seemingly populating every single page, is not my cup of tea. But this is a descriptive not a disparaging phrase: Lectures on Elliptic Boundary Value Problems is a wonderful and important book (indeed, a classic), and analysts of the right disposition should rush to get their copy, if they don't already have one (1965 being a long time ago, after all).

These lectures deal with a class of uniqueness problems in partial differential equations that can be treated by a unified method, consisting in the derivation of a second order ordinary differential inequality for a suitable norm of the solution. This inequality can be regarded as a general convexity property of the solution. Most of the uniqueness results that are dealt with are for ill-posed problems. All the problems are considered within the framework of abstract ordinary differential equations; more precisely, solutions of differential inequalities are studied in Hilbert space.

The first chapter contains some elementary lemmas concerning real solutions of certain second order differential inequalities. In the second chapter the author proves the first principal theorem on first order abstract equations and, as an application, proves Carleman's theorem on the uniqueness of the Cauchy problem for solutions of a first order linear partial differential system in two variables. Another application is the uniqueness of the Cauchy problem for parabolic problems in any number of variables. The third chapter is devoted to second order abstract differential equations or inequalities. An important application in this chapter is a simple proof of the uniqueness of the Cauchy problem for second order elliptic equations in any number of variables. Another application is the Aronszajn-Cordes unique continuation theorem (a solution of a second order elliptic equation possessing a zero of infinite order is identically zero) under minimal smoothness assumptions on the coefficients.

These are the written notes of Lectures supported by the Accademia Nazionale dei Lincei and given at the Scuola Normale Superiore of Pisa during March-April 1973. We propose to discuss here certain spectral properties of Schrödinger operators $H = -\Delta + V(x)$ ($\Delta$ the Laplacian and V a potential) which have application to scattering theory. We consider an operator H with potential V of class SR. We show that the positive point spectrum of H is a discrete set in $\mathbb{R}_{+}$. Eigenfunctions which correspond to positive eigenvalues are shown to decay rapidly. This property is shown to hold also for generalised eigenfunctions. We then establish the limiting absorbing principle, which is a basic tool in our study.

This volume presents an edited and slightly revised version of notes of lectures given at the University of Virginia in the fall of 1980. The subject of these lectures is the phenomenon of exponential decay of solutions of second order elliptic equations in unbounded domains. By way of introduction we discuss briefly the special problem of exponential decay of eigenfunctions of Schrödinger operators, a problem which motivated the present investigations.

The book is beautifully written, completely self-contained, and truly accessible to the proverbial sophisticated reader who knows only the calculus. Schrödinger operators are treated within the broader framework of second order elliptic equations with general coefficients. Included is an interesting somewhat nonstandard discussion of the selfadjointness problem for second order operators that is well worth reading. The book also contains the proof of a very general Harnack-type inequality for operators with complex coefficients which is needed to convert $L^{2}$ exponential bounds to pointwise bounds. To the best of my knowledge this is the only book devoted exclusively to the decay of eigenfunctions. It is useful both to the reader who wants to learn the subject and to the specialist who wants to know more about the general problem of the decay of solutions to second order differential equations.

Prof Shmuel Agmon is awarded the EMET Prize for paving new paths in the study of elliptic partial differential equations and their boundary value problems and for advancing the knowledge in this field, as well for his essential contribution to the development of the spectral and scattering theories of Schrödinger operators.

Shmuel Agmon ... was my instructor in the Complex Functions course during my undergraduate mathematics studies at the Hebrew University. Beyond his path-breaking contributions to mathematical research, which earned him prestigious prizes, he was, along with Micha Perles - who taught me Measure Theory - one of the two best teachers I had in my mathematics studies.

Both of them taught their courses somewhat like a television series (though one that requires a bit more concentration than those on Netflix), with a beginning, a developing storyline, and a finale. Every theorem that was proven was used to establish another, even more important and impressive theorem, leading up to a grand finale. More art than science.

The Einstein Institute of Mathematics is most pleased to send its congratulations and best wishes to Prof Emer Shmuel Agmon on his hundredth birthday. We wish you a happy birthday and many long years of happiness and good health!

The Einstein Institute expresses its condolences for the passing of Prof Shmuel Agmon, Israel Prize and EMT Award laureate, member of the Israel Academy of Sciences and Humanities, and a prominent researcher at the Institute with many celebrated results concerning Partial Differential Equations.