Mordehai Milgrom

Mordehai "Moti" Milgrom is an Israeli physicist and professor in the department of Particle Physics and Astrophysics at the Weizmann Institute in Rehovot, Israel.

Biography

He received his B.Sc. degree from the Hebrew University of Jerusalem in 1966. Later he studied at the Weizmann Institute of Science and completed his doctorate in 1972.Before 1980 he worked primarily on high-energy astrophysics and became well-known for his kinematical model of the star system SS 433.[1][2] In the academic years 1980–1981 and 1985–1986 he was at the Institute for Advanced Study in Princeton.[3] In 1983, he proposed Modified Newtonian dynamics (MOND) as an alternative to the dark matter and galaxy rotation curve problems.[4][5][6] Although preliminary work and discussions on this subject started as early as 1981.[7]
Milgrom and Modified Newtonian dynamics

Milgrom suggests that Newton's law of universal gravitation should be modified for very small accelerations, typically of the order of 10−11g and less.

"Modified Newtonian dynamics [an acceleration-based modification of dynamics or gravity] is solely the invention of Mordehai (Moti) Milgrom... it is safe to say that in the early 1980s no one but Milgrom had considered such a possible modification as an alternative to astrophysical dark matter. It was a brilliant stroke of insight to realize that astronomical systems were not only characterized by large scale but also by low internal accelerations and this could account for the known systematics in the kinematics and photometry of galactic systems. However, the idea was hardly greeted with overwhelming enthusiasm." (Sanders, R. H.)[1]

Recent findings

In 2022, a study about an astronomical observation of the tidal tails in five star clusters was published that might provide evidence of MOND.[8] Specifically, there is an uneven distribution of stars that shows no indication that any dark matter was involved in causing it.[9]
Personal life

Milgrom is married and has three daughters.
See also

Cosmic rays
Gamma-ray burst
Gamma ray and x-ray sources.

References

Sanders, R. H. (2014). "A historical perspective on modified Newtonian dynamics". Canadian Journal of Physics. 93 (2): 126–138. arXiv:1404.0531. Bibcode:2015CaJPh..93..126S. doi:10.1139/cjp-2014-0206. S2CID 119240769. page 5 of arXiv.org preprint
Milgrom, Mordehai (October 1979). "Thomson scattered lines in the spectrum of SS 433 - A powerful tool for studying the system". Astronomy and Astrophysics. 78 (3): L17–L20. Bibcode:1979A&A....78L..17M.
Mordehai, Milgrom, Community of Scholars Profile, IAS Archived 2016-03-07 at the Wayback Machine
Milgrom, Mordehai (July 1983). "A modification of the Newtonian dynamics as a possible alternative to the hidden mass hypothesis". Astrophysical Journal. 270: 365–370. Bibcode:1983ApJ...270..365M.
Milgrom, Mordehai (July 1983). "A modification of the Newtonian dynamics - Implications for galaxies". Astrophysical Journal. 270: 371–383. Bibcode:1983ApJ...270..371M.
Milgrom, Mordehai (July 1983). "A modification of the newtonian dynamics : implications for galaxy systems". Astrophysical Journal. 270: 384–389. Bibcode:1983ApJ...270..384M.
Sanders, RH (February 2015). "A modification of the newtonian dynamics : implications for galaxy systems". Canadian Journal of Physics. 93 (3): 126–138. Bibcode:2015CaJPh..93..126S.
Metcalfe, Tom (21 November 2022). "Lopsided star cluster may disprove Newton and Einstein, controversial new study claims". livescience.com. Retrieved 23 November 2022.

Kroupa, Pavel; Jerabkova, Tereza; Thies, Ingo; Pflamm-Altenburg, Jan; Famaey, Benoit; Boffin, Henri M J; Dabringhausen, Jörg; Beccari, Giacomo; Prusti, Timo; Boily, Christian; Haghi, Hosein; Wu, Xufen; Haas, Jaroslav; Zonoozi, Akram Hasani; Thomas, Guillaume; Šubr, Ladislav; Aarseth, Sverre J (26 October 2022). "Asymmetrical tidal tails of open star clusters: stars crossing their cluster's práh† challenge Newtonian gravitation". Monthly Notices of the Royal Astronomical Society. 517 (3): 3613–3639. arXiv:2210.13472. doi:10.1093/mnras/stac2563. Retrieved 23 November 2022.

Further reading
Milgrom, Mordehai (Aug 2002), "Does Dark Matter Really Exist?" (PDF), Scientific American, pp. 42–50, 52
Schilling, Govert (April 2007), "Battlefield Galactica: Dark Matter vs. MOND" (PDF), Sky & Telescope, pp. 30–36
Zhiping Li, Ran Li. (30 April 2014). "The relativistic astrodynamics of spiral tracks, localized equivalence principle and the dark matter problem of our Milky Way galaxy". Sciencepaper Online.

Physics Encyclopedia