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23
MODELS OF PARTICLE PHYSICS FROM TYPE IIB STRING THEORY AND FTHEORY: A REVIEW
, 2012
"... We review particle physics model building in type IIB string theory and Ftheory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this f ..."
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Cited by 33 (4 self)
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We review particle physics model building in type IIB string theory and Ftheory. This is a region in the landscape where in principle many of the key ingredients required for a realistic model of particle physics can be combined successfully. We begin by reviewing moduli stabilisation within this framework and its implications for supersymmetry breaking. We then review model building tools and developments in the weakly coupled type IIB limit, for both local D3branes at singularities and global models of intersecting D7branes. Much of recent model building work has been in the strongly coupled regime of Ftheory due to the presence of exceptional symmetries which allow for the construction of phenomenologically appealing Grand Unified Theories. We review both local and global Ftheory model building starting from the fundamental concepts and tools regarding how the gauge group, matter sector and operators arise, and ranging to detailed phenomenological properties explored in the literature.
Toric K3Fibred CalabiYau Manifolds with del Pezzo Divisors for String Compactifications
 JHEP 1202 (2012) 002, ARXIV:1107.0383 [HEPTH
, 2012
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Testing String Vacua in the Lab: From a Hidden CMB to Dark Forces
 in Flux Compactifications,” JHEP 1107 (2011) 114 [arXiv:1103.3705
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The Importance of Being Rigid: D6Brane Model Building on T
 6/Z2 × Z′6 with Discrete Torsion,” Nucl.Phys
, 2013
"... Model building with rigid D6branes on the Type IIA orientifold on T 6/Z2×Z′6 with discrete torsion is considered. The systematic search for models of particle physics is significantly reduced by proving new symmetries among different lattice orientations. Suitable rigid D6branes without matter in ..."
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Cited by 9 (4 self)
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Model building with rigid D6branes on the Type IIA orientifold on T 6/Z2×Z′6 with discrete torsion is considered. The systematic search for models of particle physics is significantly reduced by proving new symmetries among different lattice orientations. Suitable rigid D6branes without matter in adjoint and symmetric representations are classified, and SO(2N) and USp(2N) gauge factors on orientifold invariant D6branes are distinguished in terms of their discrete Wilson line and displacement parameters. Constraints on the nonexistence of exotic matter prohibit global completions of local MSSM and leftright symmetric models, while globally defined supersymmetric PatiSalam models are found. For the latter, only one particle generation possesses perturbative Yukawa couplings. Masses for the mild amount of exotic matter and the role of Abelian symmetries are briefly discussed. Last but not least, it is shown that for all three twotorus volumes of about the same order of magnitude, gauge coupling unification at oneloop can be achieved, while for highly unisotropic choices a low string scale in the TeV range is compatible with the observed strengths of gauge and gravitational couplings. ar X iv
GUTs in Type IIB Orientifold Compactifications
, 2009
"... We systematically analyse globally consistent SU(5) GUT models on intersecting D7branes in genuine CalabiYau orientifolds with O3 and O7planes. Beyond the wellknown tadpole and Ktheory cancellation conditions there exist a number of additional subtle but quite restrictive constraints. For the ..."
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Cited by 4 (2 self)
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We systematically analyse globally consistent SU(5) GUT models on intersecting D7branes in genuine CalabiYau orientifolds with O3 and O7planes. Beyond the wellknown tadpole and Ktheory cancellation conditions there exist a number of additional subtle but quite restrictive constraints. For the realisation of SU(5) GUTs with gauge symmetry breaking via U(1)Y flux we present two classes of suitable CalabiYau manifolds defined via del Pezzo transitions of the elliptically fibred hypersurface P1,1,1,6,9[18] and of the Quintic P1,1,1,1,1[5], respectively. To define an orientifold projection we classify all involutions on del Pezzo surfaces. We work out the model building prospects of these geometries and present five globally consistent string GUT models in detail, including a 3generation SU(5) model with no exotics whatsoever. We also realise other phenomenological features such as the 10105H Yukawa coupling and comment on the possibility of moduli stabilisation, where we find an entire new set of socalled swisscheese type CalabiYau manifolds. It is
Fourmodulus “Swiss Cheese ” chiral models
, 811
"... CalabiYau manifolds. We pay special attention to the chirality problem pointed out by Blumenhagen, Moster and Plauschinn. Namely, we thoroughly analyze the possibility of generating neutral, nonperturbative superpotentials from Euclidean D3branes in the presence of chirally intersecting D7branes ..."
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Cited by 3 (1 self)
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CalabiYau manifolds. We pay special attention to the chirality problem pointed out by Blumenhagen, Moster and Plauschinn. Namely, we thoroughly analyze the possibility of generating neutral, nonperturbative superpotentials from Euclidean D3branes in the presence of chirally intersecting D7branes. We find that taking proper account of the FreedWitten anomaly on nonspin cycles and of the Kähler cone conditions imposes severe constraints on the models. Nevertheless, we are able to create setups where the constraints
Type IIB Flux Vacua at Large Complex Structure
, 2008
"... We study models of stabilization near large complex structure in type IIB O3/O7 flux compactifications. We consider a special family of examples with a single nonvanishing Yukawa coupling in the largecomplexstructure limit, which allows us to study all possible, stable treelevel vacua very expli ..."
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We study models of stabilization near large complex structure in type IIB O3/O7 flux compactifications. We consider a special family of examples with a single nonvanishing Yukawa coupling in the largecomplexstructure limit, which allows us to study all possible, stable treelevel vacua very explicitly. We find that, by tuning fluxes, both supersymmetric and nonsupersymmetric vacua can be realized at almost any point in the largecomplexstructure moduli space of one, two, and threeparameter models. We also consider the effect of stringy corrections on treelevel vacua. We argue quite generally that in a certain regime both supersymmetric and nonsupersymmetric treelevel vacua can serve as consistent, controllable foundations for full stabilization beyond tree level (including Kähler moduli), leading to AdS or dS cosmological constants. We show how to achieve this regime in our models. Finally, we discuss some implications of minimizing at tree level the noscale form of
Systematics of String Loop Corrections in Type IIB CalabiYau Flux Compactifications
 Moduli potentials in type IIA compactifications with RR and NS flux, JHEP 0503
, 2005
"... Abstract: We study the behaviour of the string loop corrections to the N = 1 4D supergravity Kähler potential that occur in flux compactifications of IIB string theory on general CalabiYau threefolds. We give a low energy interpretation for the conjecture of Berg, Haack and Pajer for the form of t ..."
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Abstract: We study the behaviour of the string loop corrections to the N = 1 4D supergravity Kähler potential that occur in flux compactifications of IIB string theory on general CalabiYau threefolds. We give a low energy interpretation for the conjecture of Berg, Haack and Pajer for the form of the loop corrections to the Kähler potential. We check the consistency of this interpretation in several examples. We show that for arbitrary CalabiYaus, the leading contribution of these corrections to the scalar potential is always vanishing, giving an “extended noscale structure”. This result holds as long as the corrections are homogeneous functions of degree −2 in the 2cycle volumes. We use the ColemanWeinberg potential to motivate this cancellation from the viewpoint of lowenergy field theory. Finally we give a simple formula for the 1loop correction to the scalar potential in terms of the treelevel Kähler metric and the correction to the Kähler potential. We illustrate our ideas with several examples. A companion paper will use these
Radiative Fermion Masses in Local DBrane Models
"... Abstract: In the context of Dbrane model building, we present a realistic framework for generating fermion masses that are forbidden by global symmetries. We show that the string theoretical Large volume scenario circumvents the standard lore that fermion masses generated by loop effects are too sm ..."
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Abstract: In the context of Dbrane model building, we present a realistic framework for generating fermion masses that are forbidden by global symmetries. We show that the string theoretical Large volume scenario circumvents the standard lore that fermion masses generated by loop effects are too small in generic gravity mediated scenarios. We argue that the fact that in toric singularity models, the up quark masses have always a zero eigenvalue, corresponding to the lightest generation, is due to the presence of approximate global symmetries that we explicitly identify in del Pezzo singularities. These symmetries are broken by global effects and therefore proportional to inverse powers of the volume. We estimate the generic size of radiative corrections to fermion masses in different phenomenological manifestations of the Large volume scenario. Concrete realizations in terms of flavor violating softterms are estimated and contrasted with current bounds on flavour changing neutral currents. Contributions from generic extra Higgslike fields set bounds on their masses close to the GUT scale to produce realistic fermion masses.
D7Brane Moduli Space in Axion Monodromy and Fluxbrane Inflation
, 2014
"... We analyze the quantumcorrected moduli space of D7brane position moduli with special emphasis on inflationary model building. D7brane deformation moduli are key players in two recently proposed inflationary scenarios: The first, D7brane chaotic inflation, is a variant of axion monodromy inflat ..."
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We analyze the quantumcorrected moduli space of D7brane position moduli with special emphasis on inflationary model building. D7brane deformation moduli are key players in two recently proposed inflationary scenarios: The first, D7brane chaotic inflation, is a variant of axion monodromy inflation which allows for an effective 4d supergravity description. The second, fluxbrane inflation, is a stringy version of Dterm hybrid inflation. Both proposals rely on the fact that D7brane coordinates enjoy a shiftsymmetric Kähler potential at large complex structure of the CalabiYau threefold, making them naturally lighter than other fields. This shift symmetry is inherited from the mirrordual Type IIA Wilson line on a D6brane at large volume. The inflaton mass can be provided by a treelevel term in the flux superpotential. It induces a monodromy and, if tuned to a sufficiently small value, can give rise to a largefield model of inflation. Alternatively, by a sensible flux choice one can completely avoid a treelevel mass term, in which case the inflaton potential is induced via loop corrections. The positive vacuum energy can then be provided by a Dterm, leading to a smallfield model of hybrid natural inflation. In the present paper, we continue to develop a detailed understanding of the D7brane moduli space focusing among others on shiftsymmetrypreserving flux choices, fluxinduced superpotential in Type IIB/Ftheory language, and loop corrections. While the inflationary applications represent our main physics motivation, we expect that some of our findings will be useful for other phenomenological issues involving 7branes in Type IIB/Ftheory constructions.