The celestial trajectory of Jean-Pierre Luminet

Interviews 31.05.2021

With his interest in the sciences and the arts, his observation and experimentation, Jean-Pierre Luminet seems to be in the tradition of the great humanists of the Renaissance. A world-renowned specialist in black holes and cosmology, he is director of research at the CNRS and a member of the Laboratoire d'astrophysique de Marseille, after having been a member of the Laboratoire Univers et Théories (LUTH) at the Paris-Meudon Observatory.

We met him on the occasion of the release of his new book on his relationship with music, the contents of which he reveals to us in preview.

Jean-Pierre Luminet, you are an astrophysicist, a writer, a poet and a musician (you read music, you say): how do all these disciplines combine and unite in your life?
This has to do with a particular kind of mindset that goes back to my childhood; very early on I became passionate about a large number of different disciplines, and not just artistic ones either; as a child I lived in the countryside and I was already a great observer of nature: I was attentive to the life of animals, I looked at the sky and I was interested in astronomy, without thinking that one day I would become an astronomer! I loved, and still do, literature, poetry and painting; music came a little later, when I was twelve or thirteen. What has always attracted me are the various forms of creative thought; and, in parallel with my career as an astrophysicist at the CNRS, I have pursued these other activities with the same impetus; astrophysics, music, literature and painting form a whole that allows me to try to think about the world in different registers, since one does not describe it in the same way when one is working out mathematical equations or when one is in an artistic process. But in both cases, there is a creative process and imagination, and that's what interests me. A researcher in theoretical physics needs imagination as much as a musician, a writer or a poet; that is why I practice all these disciplines, convinced that these different ways of apprehending the world enrich each other and fertilise each other in a subterranean way. I devote a chapter of my latest book to this phenomenon of interaction between all these disciplines of the mind.

In addition to this, there is the aesthetic connotation, which is very important to me; I would remind you that the term "aesthetic" originates from the Greek word for cosmos, which, before designating the universe, referred to beauty, order and meaning. We have also kept the term cosmetology! Since Pythagoras, we have been trying to find relationships between the organisation of the cosmos in terms of just proportions, beauty and elegance; Pythagoras' experiment with vibrating strings made us understand that the intervals of musical harmony were also a relationship of just proportions between whole numbers. The ancients established subtle and profound links between mathematics, geometry and music - although literature and poetry also play an important role in musical inspiration. All these areas enrich the mind when one practices, as I do, fundamental physics, and aesthetics is part of the search to express the laws of the cosmos.      

You say you "place music above other forms of artistic expression". Can you elaborate on this?
This is a strictly personal opinion, linked to what has just been said above; compared to other forms of artistic expression (which I have practised), music is perhaps the most abstract language, most often using a score, the codes of which you have to know in order to read it. In this sense, music is similar to mathematics, expressed in equations that must be deciphered to make sense of them. Yet it is from this very abstract form that emotion arises, where everything is contained: an extraordinary outpouring that contrasts with the abstraction and formalisation of musical thought. I am particularly moved by music, although I am also moved by literary texts and by painting. Composers are said to hear their music before they write it; I don't think this is the case in other artistic fields. And to draw a comparison with mathematics, I find the score to be a relatively concise form of writing, a condensation of emotions in abstract form, like Einstein's equations that allow us to decode the mysteries of space-time and black holes...  

You have worked with many composers, including Gérard Grisey for Le noir de l'étoile. Was this your first collaboration with a musician? Can you tell us more about the realisation of such a project?
I tell all this in one of the biggest chapters of my book, which is due to be published next autumn. Let's say that there are three levels of interaction with composers: a real work in common with some, not on the level of musical writing but in the fact of integrating astrophysics as a support to the elaboration of the work; this was the case with Gérard Grisey and Hèctor Parra. Another kind of collaboration has been established around my texts, poems and scientific works which have inspired certain composers who have set them to music. Finally, there are the encounters I have had with personalities such as Henri Dutilleux or André Boucourechliev, with whom I have been able to exchange ideas and create bonds of friendship. In total, I must have worked with about fifteen composers. 

Gérard Grisey was the first. He had just returned from Berkeley, where he had taught for a number of years; this was in 1988; one of my Californian colleagues had played him some tape recordings that radio astronomers were playing with the cosmic rhythms that propagate in space. The most interesting ones are those of pulsars, which sound like African percussion when transposed acoustically. Gérard wanted to do something with these sounds; he didn't know me but had read my article on pulsars in the Encyclopédia Universalis; so he wrote me a letter without knowing that I was very fond of today's music and that I knew him, having a vinyl of spectral music in my record library; I answered him immediately; we became friends very quickly and began our collaboration without further delay; he came several times to the Meudon observatory to choose the type of celestial objects that interested him; there were other astronomical phenomena than pulsars that could be used acoustically, but the nature of these implacable rhythms that could interact with human rhythms particularly motivated him; I introduced him to my colleagues specialised in radio astronomy (which is not my field) and it went wonderfully well. I myself went to Berkeley in '89, when he started the score; he kept me informed of his progress and asked me to write an introductory text, which is an integral part of the work and which is recorded, although I sometimes said it orally at the beginning of certain concerts; it can also be read by actors. Gérard was very curious about advanced scientific research. I had spoken to him about some very theoretical ideas that were beginning to be evoked at the time, which I called "the foam of space-time", a term which, thirty years later, became the title of one of my last books; he was struck by this concept, which seemed to him to be in line with the dimensions of spectral music: to make the grain of sound, the foam of sound, heard; it so happened that he was in the process of writing a large piece for orchestra which he called Le temps et l'écume . Then came Le Noir de l'étoile , and I have since followed all his work.

The creation of Le Noir de l'étoile in Brussels in 1991 was almost historic!
It was programmed to coincide with the passage of the pulsars, which the audience was able to hear 'live', if one can say that about sounds that are so far away from us. We went several times to the great French radio telescope in Nançay, in Sologne, with the technicians to check that the recordings could be made and that the pulsars would be there; they only pass at certain times of the year; you have to consult the ephemeris for this. So it was the passage of the pulsar that would dictate the time of the concert. At a given moment in the score, the performers - Les Percussions de Strasbourg, who created the work - stop playing to let the pulsar be heard; of the twelve or fifteen performances I attended, not all of them attempted to be 'live'; it's all very complicated and requires extreme precision. Eventually the concept was abandoned and the sound of the pulsar was fixed on a stand. 

"The pulsars will guide our musical navigation, let's listen to these cosmic clocks ticking away their seconds. We have an appointment with the guardians of time, it's a love appointment. Let us open the window and wait for the right time". Poem by J.P. Luminet

Are many musicians interested in astrophysics? Apart from Gérard Grisey and Hèctor Parra, to whom we will return, how did you come to meet your other musical collaborators?
There is quite a large list of composers with a passion for astrophysics, especially composers of today. There were not many of them before the second half of the XXᵉ century; the advent of electroacoustic music and, with it, a generation of composers sometimes trained as engineers, encouraged this craze; there is a veritable flowering of works inspired by astrophysics, in electroacoustic music as in instrumental music for that matter: They constitute a rather large catalogue of works that I list at the end of my chapter entitled Music of the Spheres, where I cover the entire history of music, from antiquity to the present day.
I realise that 1988 was a pivotal year in my musical career, corresponding to the publication of my first popular book on black holes, which had a certain impact because it was the first of its kind. The book generated many articles in the press, and it was at that time that I began to be contacted by several composers, Gérard Grisey but also Thérèse Brenet, a professor at the CNSM, who is fascinated by the sky and celestial harmony, which she likes to disrupt with storms. She used one of my poems and wrote a piece for wind band entitled 5523 Luminet because the asteroid 5523 is named after me! I would also mention Karol Beffa with his work for choir and organ on one of my poems.
And Regis Campo, an astrophysics enthusiast, who wrote a piece in 2017 on my poem Soleil pivotal de la Galaxie from the collection Itinéraire céleste.

Your next book on astrophysics and contemporary music is a reflection of several years I suppose? Can you introduce it to us?
I have entitled it From the piano to the stars and subtitled it "musical autobiography" because I talk about my musical journey. I tell the story of my life in relation to music in a large opening chapter that launches the themes that will be developed in the book: that of my collaborations with musicians, reserving whole chapters for Gérard Grisey and Hèctor Parra; a very large chapter is devoted to other musical encounters. I also come back to the records that have marked my musical career and my piano playing; the memories of memorable concerts, especially in the Paris region. It's a three hundred page book... and I couldn't say everything! As I am more and more invited to musical conferences, I hope to have the book in hand to present it soon at the Lisztomanias in Châteauroux.  

Hector Parra's Inscape for sixteen soloists, large orchestra and electronics is the result of a rich collaboration, and I quote, "for the purpose of conceiving a psychoacoustic journey through space-time bent by the gravity of a black hole and distorted by passage through a 'wormhole'". Do you consider the composer as a research partner? In other words, does the music help you advance your intuitions and discoveries, particularly through the librettos you write for composers?
These are extraordinarily rich collaborations with remarkable people, both Gérard Grisey and Hèctor Parra, with whom I have forged very strong ties of friendship. Even more versatile than Grisey, Parra is interested in astrophysics but also in biology; he has both an exceptional scientific and literary culture. Beyond that, I couldn't say that these works make me advance in my research; it's rather the opposite that happens; I fertilise the minds of composers with my texts, which certainly have a scientific content but remain, in terms of knowledge, very popular. On the other hand, this activity continues to nourish the aesthetic vision that I can have. I attended the four performances ofInscape and came away from each one shaken. Hector even revealed to me things written at the end of his score that I would never have suspected: a sort of musical metaphor of a rather complex cosmological model, the dodecahedral universe revealed at the end of the "wormhole", which he had perfectly assimilated.

Have other encounters of this type marked your career?
I would also like to mention my collaboration with Gérard Pape, which began before Hèctor and continues to this day. He is an American composer who has settled in France. He directed the Ateliers de l'UPIC (now CCMIX ) following Xenakis and in 2008 founded the electronic music ensemble CLSI (Cercle de la Libération du Son et de L'Image) with Paul Méfano, who I also talk about in my book. Pape contacted me in 2012 and asked me to write a booklet for him in which I combine science and poetry; we began to elaborate a project entitled Atome d'espace et de temps, taking up this idea discussed with Grisey of the possible granularity, the atomisation of space and time. The project was so ambitious that it could not be completed in time, but I believe that the work is being finalised and should be ready in 2022 for a premiere in Italy. The cast has changed a little. There will be a narrator, solo voices, some instruments and electroacoustic support.

You have been contacted to be part of the scientific committee of the European Music Centre on which I would like to close this interview...
This is a project of international scope which consists of rehabilitating this historic site in Bougival where Pauline Viardot and Ivan Tourgueniev lived, where Georges Bizet completed Carmen... For twenty years, Jorge Chaminé has been working on this project which has now become the European Music Centre(EMC ) of which he is the director. The construction of an auditorium with writing workshops, master classes and student residences is planned. When I accepted the invitation, I made it clear that I was there to defend the music of our time and creation.

Interview by Michèle Tosi