Augusto Sagnotti

{{short description|Italian theoretical physicist}}

{{Infobox scientist

| name = Augusto Sagnotti

| image = Cern Sagnotti.jpg

| image_size = 200 px

| caption = (2014)

| birth_date = 1955

| birth_place = Rome, Italy

| death_date =

| death_place =

| nationality = Italian

| fields = Theoretical physics

| work_institution = Scuola Normale Superiore

| alma_mater = University of Rome "La Sapienza", California Institute of Technology

| doctoral_advisor = John H. Schwarz

| doctoral_students =

| known_for = Ultraviolet divergences of Einstein gravity, orientifolds, higher spins

| awards =

}}

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

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).{{Cite web |title=Augusto Sagnotti {{!}} ScuolaNormaleSuperiore |url=https://www.sns.it/it/persona/augusto-sagnotti |access-date=2025-06-09 |website=www.sns.it}}

Sagnotti was Junior Faculty at the University of Rome "Tor Vergata" from 1986 to 1994, then Associate Professor (1994–99) and Professor (2000-2005). 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.

Sagnotti's main contribution to physics is perhaps the analysis of the 2-loop divergences in Einstein's theory of General Relativity.

{{cite journal

|last1=Goroff |first=M. H.

|last2=Sagnotti |first2=A.

|year=1985

|title=Quantum gravity at two loops

|journal=Physics Letters B

|volume=160 |issue=1–3 |pages=81

|bibcode=1985PhLB..160...81G

|doi=10.1016/0370-2693(85)91470-4

}}

{{cite journal

|last1=Goroff |first=M. H.

|last2=Sagnotti |first2=A.

|year=1986

|title=The ultraviolet behavior of Einstein gravity

|journal=Nuclear Physics B

|volume=266 |issue=3–4 |pages=709

|bibcode=1986NuPhB.266..709G

|doi=10.1016/0550-3213(86)90193-8

}} 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,

{{cite book

|last1=Sagnotti |first1=A.

|year=1988

|chapter=Open strings and their symmetry groups

|editor1-last='t Hooft |editor1-first=G.

|editor2-last=Jaffe |editor2-first=A.

|editor3-last=Mack |editor3-first=G.

|editor4-last=Mitter |editor4-first=P. K.

|editor5-last=Stora |editor5-first=R.

|title=Nonperturbative Quantum Field Theory

|publisher=Plenum Publishing Corporation

|pages=521–528

|arxiv=hep-th/0208020

|bibcode = 2002hep.th....8020S }} with 32 half-D9-branes added in the vacuum to cancel various anomalies

{{Cite journal

|last1=Sagnotti |first1=A.

|year=1992

|title=A note on the Green–Schwarz mechanism in open-string theories

|journal=Physics Letters B

|volume=294 |issue=2 |pages=196–203

|arxiv=hep-th/9210127

|bibcode=1992PhLB..294..196S

|doi=10.1016/0370-2693(92)90682-T

|s2cid=14528538

}}

{{Cite journal

|last1=Angelantonj |first1=C.

|last2=Sagnotti |first2=A.

|year=2002

|title=Open strings

|journal=Physics Reports

|volume=371 |issue=376 |pages=1–150

|arxiv=hep-th/0204089

|bibcode=2002PhR...371....1A

|doi=10.1016/S0370-1573(02)00273-9

|s2cid=119334893

}} and offered the elucidation of the key properties of orientifold constructions and of Conformal Field Theory on non-orientable surfaces.

{{cite journal

|last1=Pradisi |first=G.

|last2=Sagnotti |first2=A.

|year=1989

|title=Open string orbifolds

|journal=Physics Letters B

|volume=216 |issue=1–2 |pages=59

|bibcode=1989PhLB..216...59P

|doi=10.1016/0370-2693(89)91369-5

}}

{{cite journal

|last1=Bianchi |first=M.

|last2=Sagnotti |first2=A.

|year=1990

|title=On the systematics of open string theories

|journal=Physics Letters B

|volume=247 |issue=4 |pages=517

|bibcode=1990PhLB..247..517B

|doi=10.1016/0370-2693(90)91894-H

}}

{{cite journal

|last1=Bianchi|first=M.

|last2=Pradisi |first2=G.

|last3=Sagnotti |first3=A.

|year=1992

|title=Toroidal compactification and symmetry breaking in open string theories

|journal=Nuclear Physics B

|volume=376 |issue=2|pages=362

|bibcode=1992NuPhB.376..365B

|doi=10.1016/0550-3213(92)90129-Y

}}

{{Cite journal

|last1=Fioravanti |first1=D.

|last2=Pradisi |first2=G.

|last3=Sagnotti |first3=A.

|year=1994

|title=Sewing constraints and non-orientable open strings

|journal=Physics Letters B

|volume=321 |issue=4 |pages=349–354

|arxiv=hep-th/9311183

|bibcode=1994PhLB..321..349F

|doi=10.1016/0370-2693(94)90255-0

|s2cid=15330492

}}

{{Cite journal

|last1=Pradisi |first1=Gianfranco

|last2=Sagnotti |first2=Augusto

|last3=Stanev |first3=Yassen S.

|year=1996

|title=Completeness conditions for boundary operators in 2D conformal field theory

|journal=Physics Letters B

|volume=381 |issue= 1–3|pages=97–104

|arxiv=hep-th/9603097

|bibcode=1996PhLB..381...97P

|doi=10.1016/0370-2693(96)00578-3

|s2cid=119096336

}} He also discovered the 10D "0B' string", including both open and closed strings, non supersymmetric but free of tachyons.

{{cite arXiv

|last1=Sagnotti |first1=A.

|year=1995

|title=Some properties of open-string theories

|eprint=hep-th/9509080

}}

{{Cite journal

|last1=Sagnotti |first1=A.

|year=1997

|title=Surprises in open-string perturbation theory

|journal=Nuclear Physics B: Proceedings Supplements

|volume=56 |issue=3 |pages=332–343

|arxiv=hep-th/9702093

|bibcode=1997NuPhS..56..332S

|doi=10.1016/S0920-5632(97)00344-7

|s2cid=13867997

}} He has worked extensively on higher spins, arriving at a geometric formulation of their free field equations in terms of higher-spin curvatures.

{{cite journal

|last1=Francia |first=D.

|last2=Sagnotti |first2=A.

|year=2002

|title=Free geometric equations for higher spins

|journal=Physics Letters B

|volume=543 |issue=3–4|pages=303

|bibcode=2002PhLB..543..303F

|doi=10.1016/S0370-2693(02)02449-8

|arxiv = hep-th/0207002 |s2cid=14912668

}}

More recently, Sagnotti has been working on the proposal of a possible link between "brane supersymmetry breaking",

{{Cite journal

|last1=Sugimoto |first1=S.

|year=1999

|title=Anomaly cancellations in the type I D9-D{{overline|9}} system and the USp(32) string theory

|journal=Progress of Theoretical Physics

|volume=102 |issue=3 |pages=685–699

|arxiv=hep-th/9905159

|bibcode=1999PThPh.102..685S

|doi=10.1143/PTP.102.685

|s2cid=14476861

}}

{{Cite journal

|last1=Antoniadis |first1=I.

|last2=Dudas |first2=E.

|last3=Sagnotti |first3=A.

|year=1999

|title=Brane supersymmetry breaking

|journal=Physics Letters B

|volume=464 |issue= 1–2|pages=38–45

|arxiv=hep-th/9908023

|bibcode=1999PhLB..464...38A

|doi=10.1016/S0370-2693(99)01023-0

|s2cid=16185036

}}

{{Cite journal

|last1=Angelantonj |first1=C.

|year=2000

|title=Comments on open-string orbifolds with a non-vanishing Bab

|journal=Nuclear Physics B

|volume=566 |issue=1–2

|pages=126–150

|arxiv=hep-th/9908064

|bibcode=2000NuPhB.566..126A

|doi=10.1016/S0550-3213(99)00662-8

|s2cid=15795436

}}

{{Cite journal

|last1=Aldazabal |first1=G.

|last2=Uranga |first2=A. M.

|year=1999

|title=Tachyon-free non-supersymmetric type IIB orientifolds via brane-antibrane systems

|journal=Journal of High Energy Physics

|volume=1999 |issue=10 |pages=24

|arxiv=hep-th/9908072

|bibcode=1999JHEP...10..024A

|doi=10.1088/1126-6708/1999/10/024

|s2cid=15612821

}} and the onset of the inflationary phase, and on the exploration of some of its possible imprints on the CMB,

{{Cite journal

|last1=Kitazawa |first1=N.

|last2=Sagnotti |first2=A.

|year=2014

|title=Pre-inflationary clues from string theory?

|journal=Journal of Cosmology and Astroparticle Physics

|volume=2014 |issue=4 |pages=17

|arxiv=1402.1418

|bibcode=2014JCAP...04..017K

|doi=10.1088/1475-7516/2014/04/017

|s2cid=119232246

}} in particular, the proposal that the low value of the CMB quadrupole

{{Cite web

|last=Hu |first=W.

|date=

|title=Quadrupole types and polarization patterns

|url=http://background.uchicago.edu/~whu/intermediate/polarization/polar4.html

|publisher=University of Chicago

|accessdate=2014-07-25

}} and a first peak for l ~5

{{Cite web

|last=Abdalla |first=F. B.

|date=

|title=Observational cosmology: The CMB

|url=http://zuserver2.star.ucl.ac.uk/~hiranya/PHAS3136/PHAS3136/PHAS3136_files/Cosmo6_101112_cmbpower.pdf

|website =

|publisher=University College London

|accessdate=2014-07-26

}} 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,{{Cite web |title=I Premi SIGRAV |url=http://sigrav.na.infn.it/attivita/premi-sigrav/?lang=en |archive-url=https://web.archive.org/web/20190212070453/http://sigrav.na.infn.it/attivita/premi-sigrav/?lang=en |archive-date=February 12, 2019 |access-date=March 18, 2021}} 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.{{Cite news |date=9 January 2019 |title=Von Humboldt Foundation Prizes awarded to Professor Ferrara and Professor Sagnotti |work=Normale News |url=https://normalenews.sns.it/von-humboldt-foundation-prizes-awarded-to-professor-ferrara-and-professor-sagnotti |access-date=18 March 2021}} He was also Andrejewski Lecturer at Humboldt Universitat in Berlin in 1999.

Books

  • String Theory, eds. C. Procesi and A. Sagnotti (Academic Press, 1988)
  • String Theory, Quantum Gravity and the Unification of the Fundamental Interactions, eds. M. Bianchi, F. Fucito, V. Marinari and A. Sagnotti (World Scientific, 1992)
  • Classical and Quantum Statistical Physics, by C. Heissenberg and A. Sagnotti (Cambridge Univ. Press, 2022)

References

{{reflist|2}}