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Journal articles on the topic 'Stringy instantons'

Author: Grafiati

Published: 14 March 2023

Last updated: 31 July 2025

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1

Brustein, Ram, and Burt A. Ovrut. "Stringy instantons." Physics Letters B 309, no. 1-2 (1993): 45–52. http://dx.doi.org/10.1016/0370-2693(93)91501-d.

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2

Frau, M. "Stringy instantons and dualities." Fortschritte der Physik 59, no. 7-8 (2011): 683–89. http://dx.doi.org/10.1002/prop.201100022.

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3

Gorbunov, I. V., and A. A. Sharapov. "String with noncommutative world-sheet and stringy instantons." Physics Letters B 531, no. 3-4 (2002): 255–62. http://dx.doi.org/10.1016/s0370-2693(02)01500-9.

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4

Argurio, Riccardo, Matteo Bertolini, Gabriele Ferretti, Christoffer Petersson, and Alberto Lerda. "Stringy instantons at orbifold singularities." Journal of High Energy Physics 2007, no. 06 (2007): 067. http://dx.doi.org/10.1088/1126-6708/2007/06/067.

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5

Aharony, Ofer, and Shamit Kachru. "Stringy instantons and cascading quivers." Journal of High Energy Physics 2007, no. 09 (2007): 060. http://dx.doi.org/10.1088/1126-6708/2007/09/060.

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6

Amariti, Antonio, Luciano Girardello, and Alberto Mariotti. "Stringy instantons as strong dynamics." Journal of High Energy Physics 2008, no. 11 (2008): 041. http://dx.doi.org/10.1088/1126-6708/2008/11/041.

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7

Amariti, Antonio, Luciano Girardello, and Alberto Mariotti. "Stringy instantons from Seiberg duality." Nuclear Physics B - Proceedings Supplements 192-193 (July 2009): 161–62. http://dx.doi.org/10.1016/j.nuclphysbps.2009.07.066.

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8

Distler, Jacques, and Shamit Kachru. "Quantum symmetries and stringy instantons." Physics Letters B 336, no. 3-4 (1994): 368–75. http://dx.doi.org/10.1016/0370-2693(94)90547-9.

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9

Amariti, A., L. Girardello, and A. Mariotti. "Stringy instantons from Seiberg duality." Fortschritte der Physik 57, no. 5-7 (2009): 478–84. http://dx.doi.org/10.1002/prop.200900055.

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10

Florea, Bogdan, Shamit Kachru, John McGreevy, and Natalia Saulina. "Stringy instantons and quiver gauge theories." Journal of High Energy Physics 2007, no. 05 (2007): 024. http://dx.doi.org/10.1088/1126-6708/2007/05/024.

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11

Petersson, Christoffer. "Superpotentials from stringy instantons without orientifolds." Journal of High Energy Physics 2008, no. 05 (2008): 078. http://dx.doi.org/10.1088/1126-6708/2008/05/078.

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12

Condeescu, C. "Stringy instantons and magnetized brane models." Fortschritte der Physik 58, no. 7-9 (2010): 875–78. http://dx.doi.org/10.1002/prop.201000020.

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13

Addazi, Andrea. "More about neutron Majorana mass from exotic instantons: An alternative mechanism in low-scale string theory." Modern Physics Letters A 31, no. 17 (2016): 1650109. http://dx.doi.org/10.1142/s0217732316501091.

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We discuss an alternative for baryon-violating six quarks transition in the context of low scale string theory. In particular, with M[Formula: see text] = 10–103 TeV, such a transition can be mediated by two color-triplets through a quartic coupling with down-quarks, generated by exotic instantons, in a calculable and controllable way. We show how flavor-changing neutral currents (FCNCs) limits on color-triplet mass are well compatible with [Formula: see text] oscillation ones. If an [Formula: see text] transition was found, this would be an indirect hint for our model. This would strongly mot

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14

Brustein, Ram, and Burt A. Ovrut. "Nonperturbative Effects in 2D String Theory or, Beyond the Liouville Wall." International Journal of Modern Physics A 12, no. 20 (1997): 3477–515. http://dx.doi.org/10.1142/s0217751x9700181x.

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We discuss continuous and discrete sectors in the collective field theory of D = 1 matrix models. A canonical Lorentz-invariant field theory extension of collective field theory is presented and its classical solutions in Euclidean and Minkowski space are found. We show that the discrete, low density sector of collective field theory includes single eigenvalue Euclidean instantons which tunnel between different vacua of the extended theory. We further show that these "stringy" instantons induce nonperturbative effective operators of strength [Formula: see text] in the extended theory. The rela

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15

Kiritsis, Elias, Michael Lennek, and Bert Schellekens. "orientifolds, Yukawa couplings, stringy instantons and proton decay." Nuclear Physics B 829, no. 1-2 (2010): 298–324. http://dx.doi.org/10.1016/j.nuclphysb.2009.12.012.

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16

MAVROMATOS, NICK E., SARBEN SARKAR, and WALTER TARANTINO. "CONDENSATE STRUCTURE OF D-BRANE DEFECT INDUCED FLAVOR VACUUM." Modern Physics Letters A 28, no. 11 (2013): 1350045. http://dx.doi.org/10.1142/s0217732313500454.

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It is argued that four-Fermi interactions induced by non-perturbative effects due to scattering of stringy matter from D-particles, D-instantons and more generally bulk gauge fields in brane models with large extra dimensions have, in specific situations, condensate structure described by flavor vacua.

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17

Ibáñez, L. E., and R. Richter. "Stringy instantons and Yukawa couplings in MSSM-like orientifold models." Journal of High Energy Physics 2009, no. 03 (2009): 090. http://dx.doi.org/10.1088/1126-6708/2009/03/090.

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18

NITTA, MUNETO. "KNOTTED INSTANTONS FROM ANNIHILATIONS OF MONOPOLE–INSTANTON COMPLEX." International Journal of Modern Physics A 28, no. 32 (2013): 1350172. http://dx.doi.org/10.1142/s0217751x13501728.

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Monopoles and instantons are sheets (membranes) and strings in d = 5+1 dimension, respectively, and instanton strings can terminate on monopole sheets. We consider a pair of monopole and antimonopole sheets which is unstable to decay and results in a creation of closed instanton strings. We show that when an instanton string is stretched between the monopole sheets, there remains a new topological soliton of codimension five after the pair annihilation, i.e. a twisted closed instanton string or a knotted instanton.

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19

Gendler, Naomi, David J. E. Marsh, Liam McAllister, and Jakob Moritz. "Glimmers from the axiverse." Journal of Cosmology and Astroparticle Physics 2024, no. 09 (2024): 071. http://dx.doi.org/10.1088/1475-7516/2024/09/071.

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Abstract We study axion-photon couplings in compactifications of type IIB string theory. We find that these couplings are systematically suppressed compared to the inverse axion periodicity, as a result of two effects. First, couplings to the QED theta angle are suppressed for axion mass eigenstates that are light compared to the mass scale set by stringy instantons on the cycle supporting QED. Second, in compactifications with many axions the intersection matrix is sparse, making kinetic mixing weak. We study the resulting phenomenology in an ensemble of 200,000 toy models constructed from th

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20

BIANCHI, MASSIMO, and MARINE SAMSONYAN. "NOTES ON UNORIENTED D-BRANE INSTANTONS." International Journal of Modern Physics A 24, no. 31 (2009): 5737–63. http://dx.doi.org/10.1142/s0217751x09048022.

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We review basic aspects of worldsheet and penta-brane instantons as well as (unoriented) D-brane instantons, which is our main focus here, and threshold corrections to BPS-saturated couplings. We then consider nonperturbative superpotentials generated by "gauge" and "exotic" instantons living on D3-branes at orientifold singularities. Moreover, we discuss the interplay between worldsheet and D-string instantons on T4/Z2. We focus on a 4-Fermi amplitude, give Heterotic and perturbative Type I descriptions, and offer a multi-D-string instanton interpretation. We conclude with possible interestin

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21

Antonov, Dmitry. "Yang–Mills Instantons in the Dual-Superconductor Vacuum Can Become Confining." Universe 9, no. 6 (2023): 257. http://dx.doi.org/10.3390/universe9060257.

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As known, the realistic, exponential, fall-off of the rate of production of light mesons in the chromo-electric field of a quark–antiquark string, as a function of the meson mass, can be obtained from the Schwinger-formula Gaussian fall-off within a phenomenological approach which assumes a certain distribution of the string tension. This approach gets a clear meaning in the London limit of the dual superconductor, where the logarithmic increase of the chromo-electric field towards the core of the string leads precisely to the change of the Gaussian fall-off to the exponential one, thus allowi

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22

Bischoff, Jan, and Olaf Lechtenfeld. "Path-Integral Quantization of the (2,2) String." International Journal of Modern Physics A 12, no. 27 (1997): 4933–71. http://dx.doi.org/10.1142/s0217751x97002632.

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A complete treatment of the (2,2) NSR string in flat (2 + 2)-dimensional space–time is given, from the formal path integral over N = 2 super Riemann surfaces to the computational recipe for amplitudes at any loop or gauge instanton number. We perform in detail the superconformal gauge fixing, discuss the spectral flow, and analyze the supermoduli space with emphasis on the gauge moduli. Background gauge field configurations in all instanton sectors are constructed. We develop chiral bosonization on punctured higher-genus surfaces in the presence of gauge moduli and instantons. The BRST cohomol

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23

LEONTARIS, G. K. "INSTANTON INDUCED CHARGED FERMION AND NEUTRINO MASSES IN A MINIMAL STANDARD MODEL SCENARIO FROM INTERSECTING D-BRANES." International Journal of Modern Physics A 24, no. 32 (2009): 6035–49. http://dx.doi.org/10.1142/s0217751x09047351.

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String instanton Yukawa corrections from Euclidean D-branes are investigated in an effective Standard Model theory obtained from the minimal U (3)× U (2)× U (1) D-brane configuration. In the case of the minimal chiral and Higgs spectrum, it is found that superpotential contributions are induced by string instantons for the perturbatively forbidden entries of the up- and down-quark mass matrices. Analogous nonperturbative effects generate heavy Majorana neutrino masses and a Dirac neutrino texture with factorizable Yukawa couplings. For this latter case, a specific example is worked out where i

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24

Billó, Marco, Pietro Fré, Riccardo D'auria, Sergio Ferrara, Paolo Soriani, and Antoine Van Proeyen. "R Symmetry and the Topological Twist of N = 2 Effective Supergravities of Heterotic Strings." International Journal of Modern Physics A 12, no. 02 (1997): 379–418. http://dx.doi.org/10.1142/s0217751x97000475.

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We discuss R symmetries in locally supersymmetric N = 2 gauge theories coupled to hypermultiplets which can be thought of as effective theories of heterotic superstring models. In this type of supergravities a suitable R symmetry exists and can be used to topologically twist the theory: the vector multiplet containing the dilaton–axion field has different R charge assignments with respect to the other vector multiplets. Correspondingly a system of coupled instanton equations emerges, mixing gravitational and Yang–Mills instantons with triholomorphic hyperinstantons and axion instantons. For th

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25

CURIO, GOTTFRIED. "SUPERPOTENTIAL OF THE M-THEORY CONIFOLD AND TYPE IIA STRING THEORY." International Journal of Modern Physics A 19, no. 04 (2004): 521–55. http://dx.doi.org/10.1142/s0217751x04017720.

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The membrane instanton superpotential for M-theory on the G2 holonomy manifold given by the cone on S3×S3 is given by the dilogarithm and has Heisenberg monodromy group in the quantum moduli space. We compare this to a Heisenberg group action on the type IIA hypermultiplet moduli space for the universal hypermultiplet, to metric corrections from membrane instantons related to a twisted dilogarithm for the deformed conifold and to a flat bundle related to a conifold period, the Heisenberg group and the dilogarithm appearing in five-dimensional Seiberg/Witten theory.

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26

SENGUPTA, SOUMITRA, and PARTHASARATHI MAJUMDAR. "STRINGY EFFECTS ON SUPERSYMMETRY BREAKING IN LOW ENERGY SUPERGRAVITY THEORIES." International Journal of Modern Physics A 06, no. 01 (1991): 41–58. http://dx.doi.org/10.1142/s0217751x91000046.

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The possibility of soft supersymmetry breaking at the tree level of string-inspired low energy supergravity theory is investigated. It is shown that the stringy quantum effects like the world sheet instanton and string loop effects can induce soft supersymmetry breakings at the tree level of the observable sector. Generic mass terms and trilinear soft breaking terms that arise are calculated.

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27

KATO, NORIJI, and IKUO SENDA. "PHASE TRANSITION DUE TO NON-CONTRACTIBLE LOOP IN HETEROTIC STRING D<10." International Journal of Modern Physics A 05, no. 04 (1990): 771–87. http://dx.doi.org/10.1142/s0217751x90000350.

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The heterotic string of the uncompactified dimensions less than ten, D<10, without space-time supersymmetry is considered. The states which have excitations only in the instanton sectors appear in the spectrum. These states become tachyonic below or above a certain scale of the compactified space and make the vacuum unstable. These phenomena are understood as phase transitions due to noncontractible loop on the compactified space. The investigation into the effective potential tells that the phase transition is of first order. The properties of the new phase are studied both in the field th

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28

Lugo, Adrián R. "SO(3)×U(1) Isometric Instantons with Non-Abelian Hair in Four-Dimensional String Theory." Modern Physics Letters A 12, no. 25 (1997): 1847–58. http://dx.doi.org/10.1142/s0217732397001886.

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We compute the exact effective string vacuum backgrounds of the level k=81/19 SU(2,1)/U(1) coset model. A compact SU(2) isometry present in this seven-dimensional solution allows one to interpret it after compactification as a four-dimensional non-Abelian SU(2) charged instanton with a singular submanifold and an SO(3) × U(1) isometry. The semiclassical backgrounds, solutions of the type II strings, present similar characteristics

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29

CHERKIS, SERGEY A. "PERIODIC MONOPOLES IN STRING THEORY." International Journal of Modern Physics A 16, supp01c (2001): 970–74. http://dx.doi.org/10.1142/s0217751x01008631.

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Periodic solutions of Bogomolny equation have novel Gravitational Instantons as their moduli spaces. String theory allows to identify these moduli spaces with moduli spaces of Hitchin systems as well as with Coulomb branches of Seiberg-Witten gauge theories on a space with one compact direction. We classify these Gravitatial Instantons. We also perform Nahm transform of Periodic Monopoles establishing the correspondence with Hitchin systems predicted by String Theory.

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30

Frau, M., and A. Lerda. "Gauge instantons from open strings." Fortschritte der Physik 52, no. 67 (2004): 606–11. http://dx.doi.org/10.1002/prop.200410151.

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31

Witten, Edward. "Small instantons in string theory." Nuclear Physics B 460, no. 3 (1996): 541–59. http://dx.doi.org/10.1016/0550-3213(95)00625-7.

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32

Lotay, Jason, та Henrique Sá Earp. "The heterotic 𝐺₂ system on contact Calabi–Yau 7-manifolds". Transactions of the American Mathematical Society, Series B 10, № 26 (2023): 907–43. http://dx.doi.org/10.1090/btran/129.

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We obtain non-trivial approximate solutions to the heterotic G 2 \mathrm {G}_2 system on the total spaces of non-trivial circle bundles over Calabi–Yau 3 3 -orbifolds, which satisfy the equations up to an arbitrarily small error, by adjusting the size of the S 1 S^1 fibres in proportion to a power of the string constant α ′ \alpha ’ . Each approximate solution provides a cocalibrated G 2 \mathrm {G}_2 -structure, the torsion of which realises a non-trivial scalar field, a constant (trivial) dilaton field and an H H -flux with non-trivial Chern–Simons defect. The approximate solutions also incl

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33

Billó, Marco, Marialuisa Frau, Igor Pesando, Francesco Fucito, Alberto Lerda, and Antonella Liccardo. "Classical gauge instantons from open strings." Journal of High Energy Physics 2003, no. 02 (2003): 045. http://dx.doi.org/10.1088/1126-6708/2003/02/045.

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34

Green, Michael B., and Pierre Vanhove. "D-instantons, strings and M-theory." Physics Letters B 408, no. 1-4 (1997): 122–34. http://dx.doi.org/10.1016/s0370-2693(97)00785-5.

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35

Szabo, Richard J. "Instantons, Topological Strings, and Enumerative Geometry." Advances in Mathematical Physics 2010 (2010): 1–70. http://dx.doi.org/10.1155/2010/107857.

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We review and elaborate on certain aspects of the connections between instanton counting in maximally supersymmetric gauge theories and the computation of enumerative invariants of smooth varieties. We study in detail three instances of gauge theories in six, four, and two dimensions which naturally arise in the context of topological string theory on certain noncompact threefolds. We describe how the instanton counting in these gauge theories is related to the computation of the entropy of supersymmetric black holes and how these results are related to wall-crossing properties of enumerative

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36

Halmagyi, Nick, Ilarion V. Melnikov, and Savdeep Sethi. "Instantons, hypermultiplets and the heterotic string." Journal of High Energy Physics 2007, no. 07 (2007): 086. http://dx.doi.org/10.1088/1126-6708/2007/07/086.

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37

Saffin, P. M., Anupam Mazumdar, and E. J. Copeland. "Instantons from low energy string actions." Physics Letters B 435, no. 1-2 (1998): 19–24. http://dx.doi.org/10.1016/s0370-2693(98)00797-7.

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38

Faulkner, Thomas, and Hong Liu. "Meson widths from string worldsheet instantons." Physics Letters B 673, no. 2 (2009): 161–65. http://dx.doi.org/10.1016/j.physletb.2009.01.071.

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39

Cámara, P. G., E. Dudas, T. Maillard, and G. Pradisi. "String instantons, fluxes and moduli stabilization." Nuclear Physics B 795, no. 1-2 (2008): 453–89. http://dx.doi.org/10.1016/j.nuclphysb.2007.11.026.

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40

Robertson, G. D. "Torus knots are rigid string instantons." Physics Letters B 226, no. 3-4 (1989): 244–50. http://dx.doi.org/10.1016/0370-2693(89)91189-1.

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41

Pawełczyk, Jacek. "New rigid string instantons in R4." Physics Letters B 387, no. 2 (1996): 287–93. http://dx.doi.org/10.1016/0370-2693(96)01041-6.

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42

Bianchi, M., F. Fucito, G. C. Rossi, and M. Martellini. "ALE instantons in string effective theory." Nuclear Physics B 440, no. 1-2 (1995): 129–70. http://dx.doi.org/10.1016/0550-3213(94)00552-p.

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43

Englert, Frangois, Laurent Houart, and Paul Windey. "Black hole entropy and string instantons." Nuclear Physics B 458, no. 1-2 (1996): 231–48. http://dx.doi.org/10.1016/0550-3213(95)00554-4.

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44

Diaconescu, D. E., B. Florea, and A. Grassi. "Geometric transitions and open string instantons." Advances in Theoretical and Mathematical Physics 6, no. 4 (2002): 619–42. http://dx.doi.org/10.4310/atmp.2002.v6.n4.a2.

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45

Khuri, Ramzi R. "Monopoles and instantons in string theory." Physical Review D 46, no. 10 (1992): 4526–32. http://dx.doi.org/10.1103/physrevd.46.4526.

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46

FIORE, R., D. GALEAZZI, L. MASPERI, and A. MEGEVAND. "STRINGS AND NON-TOPOLOGICAL SOLITONS." Modern Physics Letters A 09, no. 06 (1994): 557–68. http://dx.doi.org/10.1142/s0217732394003798.

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We have numerically calculated topological and non-topological solitons in two spatial dimensions with Chern-Simons term. Their quantum stability, as well as that of the Maxwell vortex, is analyzed by means of bounce instantons which involve three-dimensional strings and non-topological solitons.

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47

Buchbinder, Evgeny I., Burt A. Ovrut, and Rene Reinbacher. "Instanton moduli in string theory." Journal of High Energy Physics 2005, no. 04 (2005): 008. http://dx.doi.org/10.1088/1126-6708/2005/04/008.

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48

Behrndt, Klaus, Stefan Förste, and Stefan Schwager. "Instanton effects in string cosmology." Nuclear Physics B 508, no. 1-2 (1997): 391–408. http://dx.doi.org/10.1016/s0550-3213(97)80018-1.

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49

Krefl, Daniel. "Gauge theory analog of some “stringy” D-instantons." Physical Review D 78, no. 6 (2008). http://dx.doi.org/10.1103/physrevd.78.066004.

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50

Argurio, Riccardo, Davide Forcella, Alberto Mariotti, Daniele Musso, and Christoffer Petersson. "Field theory interpretation of $ \mathcal{N} $ = 2 stringy instantons." Journal of High Energy Physics 2013, no. 2 (2013). http://dx.doi.org/10.1007/jhep02(2013)002.

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