Augusto Sagnotti

Last updated
Augusto Sagnotti
Cern Sagnotti.jpg
(2014)
Born1955
Nationality Italian
Alma materUniversity of Rome "La Sapienza", California Institute of Technology
Known forUltraviolet divergences of Einstein gravity, orientifolds, higher spins
Scientific career
Fields Theoretical physics
Institutions Scuola Normale Superiore
Doctoral advisor John H. Schwarz

Augusto Sagnotti (born 1955) is an Italian theoretical physicist at Scuola Normale (since 2005).

Contents

Biography

Sagnotti earned a Laurea in Electrical Engineering from the University of Rome "La Sapienza" in 1978 (advisors: Bruno Crosignani and Paolo Di Porto); and a Ph.D. in Theoretical Physics from Caltech in 1983 (advisor: John H. Schwarz). He was Post-Doctoral Fellow at Caltech (1983–84) and Miller Research Fellow at U.C. Berkeley (1984–86).[ citation needed ]

Sagnotti was Junior Faculty at the University of Rome "Tor Vergata" from 1986 to 1994, then Associate Professor (1994–99) and Professor (2000-2005).[ citation needed ] His research activity has been devoted to the quantization of the gravitational field, to String Theory, to Conformal Field Theory and to Higher-Spin Gauge Fields.[ citation needed ]

Sagnotti's main contribution to physics is perhaps the analysis of the 2-loop divergences in Einstein's theory of General Relativity. [1] [2] Moreover, he was the first to propose, in 1987, that the type I string theory can be obtained as an orientifold of type IIB string theory, [3] with 32 half-D9-branes added in the vacuum to cancel various anomalies [4] [5] and offered the elucidation of the key properties of orientifold constructions and of Conformal Field Theory on non-orientable surfaces. [6] [7] [8] [9] [10] He also discovered the 10D "0B' string", including both open and closed strings, non supersymmetric but free of tachyons. [11] [12] He has worked extensively on higher spins, arriving at a geometric formulation of their free field equations in terms of higher-spin curvatures. [13]

More recently, Sagnotti has been working on the proposal of a possible link between "brane supersymmetry breaking", [14] [15] [16] [17] and the onset of the inflationary phase, and on the exploration of some of its possible imprints on the CMB, [18] in particular, the proposal that the low value of the CMB quadrupole [19] and a first peak for l ~5 [20] be a manifestation of the onset of the inflationary phase.

Awards and honors

Sagnotti received the Carosio Prize from the University of Rome “La Sapienza” in 1979, a Miller Fellowship from U.C. Berkeley in 1984, shared with Massimo Bianchi the 1994 SIGRAV Prize of the Italian Society for General Relativity and Gravitation, [21] and received the Margherita Hack Prize for Science in 2014 for his work on the quantization of gravity and a Humboldt Research Award in 2018. [22] He was also Andrejewski Lecturer at Humboldt Universitat in Berlin in 1999.

Books

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References

  1. Goroff, M. H.; Sagnotti, A. (1985). "Quantum gravity at two loops". Physics Letters B . 160 (1–3): 81. Bibcode:1985PhLB..160...81G. doi:10.1016/0370-2693(85)91470-4.
  2. Goroff, M. H.; Sagnotti, A. (1986). "The ultraviolet behavior of Einstein gravity". Nuclear Physics B . 266 (3–4): 709. Bibcode:1986NuPhB.266..709G. doi:10.1016/0550-3213(86)90193-8.
  3. Sagnotti, A. (1988). "Open strings and their symmetry groups". In 't Hooft, G.; Jaffe, A.; Mack, G.; Mitter, P. K.; Stora, R. (eds.). Nonperturbative Quantum Field Theory. Plenum Publishing Corporation. pp. 521–528. arXiv: hep-th/0208020 . Bibcode:2002hep.th....8020S.
  4. Sagnotti, A. (1992). "A note on the GreenSchwarz mechanism in open-string theories". Physics Letters B . 294 (2): 196–203. arXiv: hep-th/9210127 . Bibcode:1992PhLB..294..196S. doi:10.1016/0370-2693(92)90682-T. S2CID   14528538.
  5. Angelantonj, C.; Sagnotti, A. (2002). "Open strings". Physics Reports . 371 (376): 1–150. arXiv: hep-th/0204089 . Bibcode:2002PhR...371....1A. doi:10.1016/S0370-1573(02)00273-9. S2CID   119334893.
  6. Pradisi, G.; Sagnotti, A. (1989). "Open string orbifolds". Physics Letters B . 216 (1–2): 59. Bibcode:1989PhLB..216...59P. doi:10.1016/0370-2693(89)91369-5.
  7. Bianchi, M.; Sagnotti, A. (1990). "On the systematics of open string theories". Physics Letters B . 247 (4): 517. Bibcode:1990PhLB..247..517B. doi:10.1016/0370-2693(90)91894-H.
  8. Bianchi, M.; Pradisi, G.; Sagnotti, A. (1992). "Toroidal compactification and symmetry breaking in open string theories". Nuclear Physics B . 376 (2): 362. Bibcode:1992NuPhB.376..365B. doi:10.1016/0550-3213(92)90129-Y.
  9. Fioravanti, D.; Pradisi, G.; Sagnotti, A. (1994). "Sewing constraints and non-orientable open strings". Physics Letters B . 321 (4): 349–354. arXiv: hep-th/9311183 . Bibcode:1994PhLB..321..349F. doi:10.1016/0370-2693(94)90255-0. S2CID   15330492.
  10. Pradisi, Gianfranco; Sagnotti, Augusto; Stanev, Yassen S. (1996). "Completeness conditions for boundary operators in 2D conformal field theory". Physics Letters B . 381 (1–3): 97–104. arXiv: hep-th/9603097 . Bibcode:1996PhLB..381...97P. doi:10.1016/0370-2693(96)00578-3. S2CID   119096336.
  11. Sagnotti, A. (1995). "Some properties of open-string theories". arXiv: hep-th/9509080 .
  12. Sagnotti, A. (1997). "Surprises in open-string perturbation theory". Nuclear Physics B: Proceedings Supplements . 56 (3): 332–343. arXiv: hep-th/9702093 . Bibcode:1997NuPhS..56..332S. doi:10.1016/S0920-5632(97)00344-7. S2CID   13867997.
  13. Francia, D.; Sagnotti, A. (2002). "Free geometric equations for higher spins". Physics Letters B . 543 (3–4): 303. arXiv: hep-th/0207002 . Bibcode:2002PhLB..543..303F. doi:10.1016/S0370-2693(02)02449-8. S2CID   14912668.
  14. Sugimoto, S. (1999). "Anomaly cancellations in the type I D9-D9 system and the USp(32) string theory". Progress of Theoretical Physics . 102 (3): 685–699. arXiv: hep-th/9905159 . Bibcode:1999PThPh.102..685S. doi:10.1143/PTP.102.685. S2CID   14476861.
  15. Antoniadis, I.; Dudas, E.; Sagnotti, A. (1999). "Brane supersymmetry breaking". Physics Letters B . 464 (1–2): 38–45. arXiv: hep-th/9908023 . Bibcode:1999PhLB..464...38A. doi:10.1016/S0370-2693(99)01023-0. S2CID   16185036.
  16. Angelantonj, C. (2000). "Comments on open-string orbifolds with a non-vanishing Bab". Nuclear Physics B . 566 (1–2): 126–150. arXiv: hep-th/9908064 . Bibcode:2000NuPhB.566..126A. doi:10.1016/S0550-3213(99)00662-8. S2CID   15795436.
  17. Aldazabal, G.; Uranga, A. M. (1999). "Tachyon-free non-supersymmetric type IIB orientifolds via brane-antibrane systems". Journal of High Energy Physics . 1999 (10): 24. arXiv: hep-th/9908072 . Bibcode:1999JHEP...10..024A. doi:10.1088/1126-6708/1999/10/024. S2CID   15612821.
  18. Kitazawa, N.; Sagnotti, A. (2014). "Pre-inflationary clues from string theory?". Journal of Cosmology and Astroparticle Physics . 2014 (4): 17. arXiv: 1402.1418 . Bibcode:2014JCAP...04..017K. doi:10.1088/1475-7516/2014/04/017. S2CID   119232246.
  19. Hu, W. "Quadrupole types and polarization patterns". University of Chicago . Retrieved 2014-07-25.
  20. Abdalla, F. B. "Observational cosmology: The CMB" (PDF). University College London . Retrieved 2014-07-26.
  21. "I Premi SIGRAV". Archived from the original on February 12, 2019. Retrieved March 18, 2021.
  22. "Von Humboldt Foundation Prizes awarded to Professor Ferrara and Professor Sagnotti". Normale News. 9 January 2019. Retrieved 18 March 2021.