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CATEGORIES:Isaac Newton Institute Seminar Series
SUMMARY:U(n) Spectral Covers from Decomposition - Hayashi\
, H (Korea Institute for Advanced Study (KIAS))
DTSTART;TZID=Europe/London:20120628T171500
DTEND;TZID=Europe/London:20120628T173000
UID:TALK38737AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/38737
DESCRIPTION:We construct decomposed spectral covers for bundle
s on elliptically fibered Calabi-Yau threefolds wh
ose structure groups are S(U(1) x U(4))\, S(U(2) x
U(3)) and S(U(1) x U(1) x U(3)) in heterotic stri
ng compactifications. The decomposition requires n
ot only the tuning of the SU(5) spectral covers bu
t also the tuning of the complex structure moduli
of the Calabi-Yau threefolds. This configuration i
s translated to geometric data on F-theory side. W
e find that the monodromy locus for two-cycles in
K3 fibered Calabi-Yau fourfolds in a stable degene
ration limit is globally factorized with squared f
actors under the decomposition conditions. This si
gnals that the monodromy group is reduced and ther
e is a U(1) symmetry in a low energy effective fie
ld theory. To support that\, we explicitly check t
he reduction of a monodromy group in a slice of th
e moduli space for an E6 gauge theory with (1+2) d
ecomposition. This may provide a systematic way fo
r constructing some F-theory models with U (1) sym
metries.\n
LOCATION:Seminar Room 1\, Newton Institute
CONTACT:Mustapha Amrani
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