David Elbaz is a French novelist and observational astrophysicist, specializing in

galaxy formation and evolution The study of galaxy formation and evolution is concerned with the processes that formed a heterogeneous universe from a homogeneous beginning, the formation of the first galaxies, the way galaxies change over time, and the processes that have ge ...

. He has been a researcher at the Astrophysics Division (AIM) of the Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA-Saclay) since 1994, where he is currently the Director of Research. He was in charge of directing the "Cosmology and Evolution of Galaxies" laboratory at AIM/CEA-Saclay for about a decade. He has also worked as the scientific advisor to the

European Space Agency , owners = , headquarters = Paris, Île-de-France, France , coordinates = , spaceport = Guiana Space Centre , seal = File:ESA emblem seal.png , seal_size = 130px , image = Views in the Main Control Room (1205 ...

for the selection of its future space missions (Astronomy Working Group) and was a member of the evaluation committee on space research and exploration for the

Centre National d'Etudes Spatiales The (CNES; French: ''Centre national d'études spatiales'') is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is und ...

(CNES) in France.

Biography

Elbaz's grandparents moved to France from

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...

at the beginning of the 20th century. He was born and raised in the

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

Métro area. He repeated a school year twice in high school. He also attended the École Nationale Supérieure de Physique (ENSPG) in

Grenoble lat, Gratianopolis , commune status = Prefecture and commune , image = Panorama grenoble.png , image size = , caption = From upper left: Panorama of the city, Grenoble’s cable cars, place Saint- ...

, where he obtained his undergraduate degree as an Engineer in 1990. He completed his

PhD PHD or PhD may refer to: * Doctor of Philosophy (PhD), an academic qualification Entertainment * '' PhD: Phantasy Degree'', a Korean comic series * ''Piled Higher and Deeper'', a web comic * Ph.D. (band), a 1980s British group ** Ph.D. (Ph.D. albu ...

in Astrophysics in 1994 at the

Université Joseph Fourier Joseph Fourier University (UJF, french: Université Joseph Fourier, also known as Grenoble I) was a French university situated in the city of Grenoble and focused on the fields of sciences, technologies and health. It is now part of the Universit ...

in Grenoble with a thesis entitled "''Origine du fer dans le milieu intra-amas et distribution du gaz X dans les amas de galaxies''". His supervisors were James Lequeux and Monique Arnaud. In 2005, he was awarded his

habilitation Habilitation is the highest university degree, or the procedure by which it is achieved, in many European countries. The candidate fulfills a university's set criteria of excellence in research, teaching and further education, usually including a ...

from the

University of Paris XI Paris-Sud University (French: ''Université Paris-Sud''), also known as University of Paris — XI (or as Université d'Orsay before 1971), was a French research university distributed among several campuses in the southern suburbs of Paris, in ...

. Elbaz has supervised 14

postdoctoral researcher A postdoctoral fellow, postdoctoral researcher, or simply postdoc, is a person professionally conducting research after the completion of their doctoral studies (typically a PhD). The ultimate goal of a postdoctoral research position is to p ...

s and 7

PhD student A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

s, two of whom received awards for their dissertations: H. Aussel (1999) and C. Schreiber (2015). Since 2005 he has taught the "Galaxy Evolution" course in the Master program, "''Recherche Astronomie, Astrophysique et Ingénierie Spatiale de Paris''".

Research areas

Elbaz has made contributions in observational extragalactic astrophysics using mostly space infrared and

submillimeter Submillimetre astronomy or submillimeter astronomy (see spelling differences) is the branch of observational astronomy that is conducted at submillimetre wavelengths (i.e., terahertz radiation) of the electromagnetic spectrum. Astronomers plac ...

observations. He has been recognized as an

ISI Highly Cited The Institute for Scientific Information (ISI) was an academic publishing service, founded by Eugene Garfield in Philadelphia in 1956. ISI offered scientometric and bibliographic database services. Its specialty was citation indexing and analysis, ...

researcher by

Clarivate Analytics Clarivate Plc is a British-American publicly traded analytics company that operates a collection of subscription-based services, in the areas of bibliometrics and scientometrics; business / market intelligence, and competitive profiling for p ...

. In 2001, using new data from the

Infrared Space Observatory The Infrared Space Observatory (ISO) was a space telescope for infrared light designed and operated by the European Space Agency (ESA), in cooperation with ISAS (now part of JAXA) and NASA. The ISO was designed to study infrared light at wavelengt ...

, Elbaz and Ranga Chary produced a suite of galaxy

spectral energy distribution A spectral energy distribution (SED) is a plot of energy versus frequency or wavelength of light (not to be confused with a 'spectrum' of flux density vs frequency or wavelength). It is used in many branches of astronomy to characterize astron ...

templates. Along with the current knowledge of the galaxy

redshift In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...

distribution, they were able to interpret the

cosmic infrared background Cosmic infrared background is infrared radiation caused by stellar dust. History Recognizing the cosmological importance of the darkness of the night sky (Olbers' paradox) and the first speculations on an extragalactic background light dates ...

as being produced to at least 70% level from dust enshrouded

star formation Star formation is the process by which dense regions within molecular clouds in The "medium" is present further soon.-->interstellar space

luminous infrared galaxies Luminous infrared galaxies or LIRGs are galaxies with luminosities, the measurement of brightness, above . They are also referred to as submillimeter galaxies (SMGs) through their normal method of detection. LIRGs are more abundant than starburst ...

.). The advent of the

Spitzer Space Telescope The Spitzer Space Telescope, formerly the Space Infrared Telescope Facility (SIRTF), was an infrared space telescope launched in 2003. Operations ended on 30 January 2020. Spitzer was the third space telescope dedicated to infrared astronomy, f ...

in 2003 enabled extremely deep observations in mid-infrared. Elbaz and his collaborations analyzed observations from the

Great Observatories Origins Deep Survey The Great Observatories Origins Deep Survey, or GOODS, is an astronomical survey combining deep observations from three of NASA's Great Observatories: the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory, al ...

and demonstrated that the star formation rate of individual galaxies increases due to environmental effects up to a critical galaxy density at redshift one, above which it decreases again, suggesting that galaxy evolution is not independent from

structure formation In physical cosmology, structure formation is the formation of galaxies, galaxy clusters and larger structures from small early density fluctuations. The universe, as is now known from observations of the cosmic microwave background radiation, beg ...

at larger scales in the

universe The universe is all of space and time and their contents, including planets, stars, galaxies, and all other forms of matter and energy. The Big Bang theory is the prevailing cosmological description of the development of the universe. Acc ...

.). Five years later, using deep far infrared observations from the

Herschel Space Observatory The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA). It was active from 2009 to 2013, and was the largest infrared telescope ever launched until the launch of the James Webb Space Telesc ...

, Elbaz led a study that revealed that most

galaxies A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...

across cosmic time form

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

s in two main modes: one placing them in the "main sequence", where their star formation rate correlates tightly with their

stellar mass Stellar mass is a phrase that is used by astronomers to describe the mass of a star. It is usually enumerated in terms of the Sun's mass as a proportion of a solar mass (). Hence, the bright star Sirius has around . A star's mass will vary over its ...

, and the other where the galaxies are more compact and form stars more efficiently departing from this correlation.). More recently, using observations from ALMA, his group discovered a dominant population of optically invisible massive galaxies in the early Universe.

Awards

Elbaz has received several noteworthy awards, including: * Chrétien Award of the

American Astronomical Society The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC. The primary objective of the AAS is to promote the adv ...

(2000) * Prix Jaffé from the Foundation of the

Institut de France The (; ) is a French learned society, grouping five , including the Académie Française. It was established in 1795 at the direction of the National Convention. Located on the Quai de Conti in the 6th arrondissement of Paris, the institute m ...

(2017) * Member of the

Academia Europaea The Academia Europaea is a pan-European Academy of Humanities, Letters, Law, and Sciences. The Academia was founded in 1988 as a functioning Europe-wide Academy that encompasses all fields of scholarly inquiry. It acts as co-ordinator of Europea ...

(2019)

Administration and service

Elbaz's contributions to the international astrophysics' community include: * Managing Editor of Astronomy & Astrophysics Journal, 2018–present * Member of the ESA

SPICA Spica is the brightest object in the constellation of Virgo and one of the 20 brightest stars in the night sky. It has the Bayer designation α Virginis, which is Latinised to Alpha Virginis and abbreviated Alpha Vir or α Vir. Analys ...

Science Team, 2018–2021 * Member of the Euclid France steering committee, 2013–present * Member of the ESA Astronomy Working Group, 2015–2018 * President of the International Space Advisory Board for the SPICA satellite for

JAXA The is the Japanese national air and space agency. Through the merger of three previously independent organizations, JAXA was formed on 1 October 2003. JAXA is responsible for research, technology development and launch of satellites into orb ...

, 2015–2016

Public outreach

Elbaz is active in public outreach activities and has been interviewed regularly on various topics of modern astrophysics by French media, including "

Le Monde ''Le Monde'' (; ) is a French daily afternoon newspaper. It is the main publication of Le Monde Group and reported an average circulation of 323,039 copies per issue in 2009, about 40,000 of which were sold abroad. It has had its own website si ...

", "

France Culture France Culture is a French public radio channel and part of Radio France. Its programming encompasses a wide variety of features on historical, philosophical, sociopolitical, and scientific themes (including debates, discussions, and documentari ...

", "

Sciences et Avenir ''Sciences et Avenir'' (meaning ''Science and Future'' in English) is a monthly French popular science magazine, owned by Claude Perdriel. Its distribution in 2019 was 231,000 copies. The editorial team also publish about 15 articles per day on th ...

", and "

France Inter France Inter () is a major French public radio channel and part of Radio France. It is a "generalist" station, aiming to provide a wide national audience with a full service of news and spoken-word programming, both serious and entertaining, li ...

". Among his presentations are "Is the Universe an illusion?" (French: ''L’Univers est-il une illusion''), "Do we live in a black hole?" (French: ''Habitons-nous dans un trou noir ?'') and "In search of the killer of galaxies" (French: ''A la recherche du tueur de galaxies'') that was presented at the Conférence Cyclope in February 2020. Elbaz has written the scenario and participated in shows that involve science and art that have been presented in various theatres in France., including: * "La tête dans les étoiles" (with the

neurobiologist A neuroscientist (or neurobiologist) is a scientist who has specialised knowledge in neuroscience, a branch of biology that deals with the physiology, biochemistry, psychology, anatomy and molecular biology of neurons, neural circuits, and glial c ...

Alain Destexhe and the

magician Magician or The Magician may refer to: Performers * A practitioner of magic (supernatural) * A practitioner of magic (illusion) * Magician (fantasy), a character in a fictional fantasy context Entertainment Books * ''The Magician'', an 18th-ce ...

Marc Feld) * "Magicosmologie" (with Marc Feld) * "Jonglerie Astrale" (with the

juggler Juggling is a physical skill, performed by a juggler, involving the manipulation of objects for recreation, entertainment, art or sport. The most recognizable form of juggling is toss juggling. Juggling can be the manipulation of one object o ...

Vincent de Lavenère)

Publications

Elbaz has published extensively in various areas of extragalactic observational astrophysics. He has been recognised as an

researcher by

. Elbaz has also authored three books: * ''"A la recherche de l'univers invisible: matière noire, énergie sombre, trous noirs"'', 2016, éditions

Odile Jacob Odile Jacob is a French publisher who founded ''Les Éditions Odile Jacob'' in the middle of the 1980s. She is also a trained scientist, studying the workings of the brain, the mind and thought. She is a member of Le Siècle.Frédéric Saliba, 'L ...

that popularises science and received also received in 2017 the "Prix Sciences et Philosophie" in 2017. *"Αναζητώντας το αόρατο σύμπαν: σκοτεινή ύλη, σκοτεινή ενέργεια, μαύρες τρύπες", 2021, Crete University Press * ''"Le vase de Pépi"'', 2007, éditions

. * ''"...et Alice Tao se souvint du futur"'', 2010, éditions

. *"''La plus belle ruse de la lumière''", 2021, éditions

References

External links

David Elbaz - Astrophysicien - YouTube channel
{{DEFAULTSORT:Elbaz, David 1966 births Living people French astrophysicists French Alternative Energies and Atomic Energy Commission Members of Academia Europaea Scientists from Paris