In retrospect: A personal view on Mosh e Flato's scientific legacy
When a talented sculptor is confronted with a block of marble , he is using tools that come from centuries of tradition and the training which he received from his masters. But from the first stroke he already has, in the back o f his mind, the design of the sculpture which he wants to extract from that block. Cr eating a masterpiece is a long and painful process, interspersed with surprises d u to the irregularities of the physical properties of the noble material he is using, an d the design continues to evolve with the artist’s maturing and subject to external in fluences. Only gradually does the shape emerge, at first visible to experts, then to the gen ral public. Beyond the technicalities, however important they may be, M oshé’s scientific life was a perfect illustration of this idea. His masterpiec e is not finished. Much polishing remains to be done, new elements still need to be ad d d to the main themes which he conceived, and entirely new themes are now be ginning to emerge from them. But a very partial view of what he had in mind can alr e dy be described. This is what I shall attempt here, based on my experience of ha ving, for about 35 years, participated with others in the elaboration of his id eas. All those who have been close to him know that he used to call me affectionately a n “idiot” more often than he used that expression for anybody else; this usu ally happened when my formulation of one of his ideas was not to his taste and need ed to be corrected, either because he did not like some of the ingredients I was ad ding or when, while striving for too precise a formulation, I obscured an essent ial point which he had purposedly stated ambiguously. François Mitterrand used to say, paraphrasing the Cardinal de Retz, “On ne sort de l’ambiguı̈té qu’à son dét riment”. In his case, this was smart politics, in Moshé’s, using seemingly ambiguous statements was the only way by which he could transmit the deep feeling which he h ad without the distortion of too precise, confining words. I hope that now, w ith him not around, my formulation will be faithful enough to the main ideas whic h he developed and often initiated. My purpose here is to show how, in retrospec t, one can look at the genesis and evolution of ideas and concepts in some of the fiel ds where Moshé made an impact that has only begun to be fully recognized. I sh all refrain from entering into technicalities, because they are covered in p art in the present volume and in recent review papers, and in order to make the ideas und erstandable to a general, scientifically educated audience. Towards the end of the 19 th century, physics seemed to have achieved a complete understanding of the world, with classical mechanics describing the motion of rigid bodies, electromagnetism waves and charged partic les, and the Lorentz force their interactions. It was only a plateau because then‘deformation dae-