123 citations · 877 across the 33 of their papers we have counts for
34 papers · 1 filter
Free Fermionic Constructions of Heterotic Strings
Ioannis Florakis, John Rizos
This chapter is an introduction to the Free Fermionic Formulation of String Theory, with emphasis on heterotic model building. After a brief review of bosonization in two dimension…
Non-supersymmetric non-tachyonic heterotic vacua with reduced rank in various dimensions
Carlo Angelantonj, Ioannis Florakis, Giorgio Leone +1
We construct rigid non-supersymmetric heterotic vacua with reduced rank and no tachyons in six and four dimensions. These configurations are based on asymmetric orbifold compactifi…
A Lightning Introduction to String Theory
Carlo Angelantonj, Ioannis Florakis
We give a lightning introduction to critical string theory, including the 26-dimensional bosonic string, the 10-dimensional superstrings and heterotic strings with and without spac…
From Free-Fermionic Constructions to Orbifolds and Back
Ioannis Florakis, John Rizos
We systematically develop the explicit map between string vacua constructed in the Free Fermionic Formulation and their toroidal orbifold counterparts. We illustra…
Tachyons and Misaligned Supersymmetry in Closed String Vacua
Carlo Angelantonj, Ioannis Florakis, Giorgio Leone
In a remarkable paper, Dienes discovered that the absence of physical tachyons in closed string theory is intimately related to oscillations in the net number of bosonic minus ferm…
Three-Generation Super No-Scale Models in Heterotic Superstrings
Ioannis Florakis, John Rizos, Konstantinos Violaris-Gountonis
We derive the conditions for the one-loop contribution to the cosmological constant to be exponentially suppressed in a class of heterotic string compactifications with three gener…
Refined Topological Amplitudes from the -Background in String Theory
Carlo Angelantonj, Ignatios Antoniadis, Ioannis Florakis +1
It was recently shown that the = 2 string topological amplitudes in the heterotic weak coupling limit generate a six-dimensional Melvin space, providing a description…
Super No-Scale Models with Pati-Salam Gauge Group
Ioannis Florakis, John Rizos, Konstantinos Violaris-Gountonis
We construct and classify heterotic models where supersymmetry is spontaneously broken à la Scherk-Schwarz. The theories contain chiral matter transforming under an…
GUT Scale Unification in Heterotic Strings
Carlo Angelantonj, Ioannis Florakis
We present a class of heterotic compactifications where it is possible to lower the string unification scale down to the GUT scale, while preserving the validity of the perturbativ…
2d orbifolds with exotic supersymmetry
Ioannis Florakis, Iñaki García-Etxebarria, Dieter Lust +1
We analyse various two dimensional theories arising from compactification of type II and heterotic string theory on asymmetric orbifolds. We find extra supersymmetry generators ari…
A Solution to the Decompactification Problem in Chiral Heterotic Strings
Ioannis Florakis, John Rizos
We present a solution to the decompactification problem of gauge thresholds in chiral heterotic string theories with two large extra dimensions, where supersymmetry is spontaneousl…
Gravitational Threshold Corrections in Non-Supersymmetric Heterotic Strings
Ioannis Florakis
We compute one-loop quantum corrections to gravitational couplings in the effective action of four-dimensional heterotic strings where supersymmetry is spontaneously broken by Sche…
Chiral Heterotic Strings with Positive Cosmological Constant
Ioannis Florakis, John Rizos
We present explicit examples of semi-realistic heterotic models with spontaneously broken supersymmetry, which dynamically lead to breaking scales much smaller than $M_{\rm Planck}…
On the Rankin-Selberg method for higher genus string amplitudes
Ioannis Florakis, Boris Pioline
Closed string amplitudes at genus are given by integrals of Siegel modular functions on a fundamental domain of the Siegel upper half-plane. When the integrand is of rapi…
from Topological Amplitudes in String Theory
Ioannis Florakis, Ahmad Zein Assi
In this paper, we explicitly construct string theory backgrounds that realise the so-called gauge theory. We prove the consistency of our models by calculating…
Generalised universality of gauge thresholds in heterotic vacua with and without supersymmetry
Carlo Angelantonj, Ioannis Florakis, Mirian Tsulaia
We study one-loop quantum corrections to gauge couplings in heterotic vacua with spontaneous supersymmetry breaking. Although in non-supersymmetric constructions these corrections…
Probing the Moduli Dependence of Refined Topological Amplitudes
Ignatios Antoniadis, Ioannis Florakis, Stefan Hohenegger +2
With the aim of providing a worldsheet description of the refined topological string, we continue the study of a particular class of higher derivative couplings in the ty…
Universality of radiative corrections to gauge couplings for strings with spontaneously broken supersymmetry
Ioannis Florakis
I review recent work on computing radiative corrections to non-abelian gauge couplings in four-dimensional heterotic vacua with spontaneously broken supersymmetry. The prototype mo…
Threshold corrections, generalised prepotentials and Eichler integrals
Carlo Angelantonj, Ioannis Florakis, Boris Pioline
We continue our study of one-loop integrals associated to BPS-saturated amplitudes in heterotic vacua. We compute their large-volume behaviour, and express them as…
Higher Spins in Hyper-Superspace
Ioannis Florakis, Dmitri Sorokin, Mirian Tsulaia
We extend the results of arXiv:1401.1645 on the generalized conformal Sp(2n)-structure of infinite multiplets of higher spin fields, formulated in spaces with extra tensorial direc…
Universality of Gauge Thresholds in Non-Supersymmetric Heterotic Vacua
Carlo Angelantonj, Ioannis Florakis, Mirian Tsulaia
We compute one-loop threshold corrections to non-abelian gauge couplings in four-dimensional heterotic vacua with spontaneously broken supersymmetry, ob…
Higher Spins in Hyperspace
Ioannis Florakis, Dmitri Sorokin, Mirian Tsulaia
We consider the Sp(2n) invariant formulation of higher spin fields on flat and curved backgrounds of constant curvature.In this formulation an infinite number of higher spin fields…
Non-Perturbative Nekrasov Partition Function from String Theory
Ignatios Antoniadis, Ioannis Florakis, Stefan Hohenegger +2
We calculate gauge instanton corrections to a class of higher derivative string effective couplings introduced in [1]. We work in Type I string theory compactified on K3xT2 and rea…
Gauged supergravities and non-geometric Q/R-fluxes from asymmetric orbifold CFT's
Cezar Condeescu, Ioannis Florakis, Costas Kounnas +1
We investigate the orbifold limits of string theory compactifications with geometric and non-geometric fluxes. Exploiting the connection between internal fluxes and structure const…