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Patrick K.S. Vaudrevange

Bio: Patrick K.S. Vaudrevange is an academic researcher from Technische Universität München. The author has contributed to research in topics: Orbifold & Heterotic string theory. The author has an hindex of 13, co-authored 24 publications receiving 786 citations.

Papers
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TL;DR: In this article, a general analysis of models with an axion and further axion-like particles (ALPs) with decay constants in the intermediate scale range, between 109 GeV and 1013 GeV, is presented.
Abstract: The recent detection of the cosmic microwave background polarimeter experiment BICEP2 of tensor fluctuations in the B-mode power spectrum basically excludes all plausible axion models where its decay constant is above 1013 GeV. Moreover, there are strong theoretical, astrophysical, and cosmological motivations for models involving, in addition to the axion, also axion-like particles (ALPs), with decay constants in the intermediate scale range, between 109 GeV and 1013 GeV. Here, we present a general analysis of models with an axion and further ALPs and derive bounds on the relative size of the axion and ALP photon (and electron) coupling. We discuss what we can learn from measurements of the axion and ALP photon couplings about the fundamental parameters of the underlying ultraviolet completion of the theory. For the latter we consider extensions of the Standard Model in which the axion and the ALP(s) appear as pseudo Nambu-Goldstone bosons from the breaking of global chiral U(1) (Peccei-Quinn (PQ)) symmetries, occurring accidentally as low energy remnants from exact discrete symmetries. In such models, the axion and the further ALP are protected from disastrous explicit symmetry breaking effects due to Planck-scale suppressed operators. The scenarios considered exploit heavy right handed neutrinos getting their mass via PQ symmetry breaking and thus explain the small mass of the active neutrinos via a seesaw relation between the electroweak and an intermediate PQ symmetry breaking scale. For a number of explicit models, we determine the parameters of the low-energy effective field theory describing the axion, the ALPs, and their interactions with photons and electrons, in terms of the input parameters, in particular the PQ symmetry breaking scales. We show that these models can accommodate simultaneously an axion dark matter candidate, an ALP explaining the anomalous transparency of the universe for γ-rays, and an ALP explaining the recently reported 3.55 keV gamma line from galaxies and clusters of galaxies, if the respective decay constants are of intermediate scale. Moreover, they do not suffer severely from the domain wall problem.

153 citations

Journal ArticleDOI
TL;DR: In this article, a new method based on outer automorphisms of the Narain space group is developed to determine flavor symmetries within compactified string theory, and a picture emerges where traditional (discrete) flavor symmetry, CP-like symmetry, and modular symmetry (like T-duality) of string theory combine to unified flavor symmetry.

150 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present a method to compute the unified flavor symmetry of the low-energy effective theory, including enhancements from the modular transformations of string theory, which is non-universal in moduli space and exhibits the phenomenon of local flavor unification.

95 citations

Journal ArticleDOI
TL;DR: In this paper, a general analysis of models with an axion and further axion-like particles (ALPs) with decay constants in the intermediate scale range, between $10^9$ GeV and $10^{13}$GeV, is presented.
Abstract: The recent detection of the cosmic microwave background polarimeter experiment BICEP2 of tensor fluctuations in the B-mode power spectrum basically excludes all plausible axion models where its decay constant is above $10^{13}$ GeV. Moreover, there are strong theoretical, astrophysical, and cosmological motivations for models involving, in addition to the axion, also axion-like particles (ALPs), with decay constants in the intermediate scale range, between $10^9$ GeV and $10^{13}$ GeV. Here, we present a general analysis of models with an axion and further ALPs and derive bounds on the relative size of the axion and ALP photon (and electron) coupling. We discuss what we can learn from measurements of the axion and ALP photon couplings about the fundamental parameters of the underlying ultraviolet completion of the theory. For the latter we consider extensions of the Standard Model in which the axion and the ALP(s) appear as pseudo Nambu-Goldstone bosons from the breaking of global chiral $U(1)$ (Peccei-Quinn (PQ)) symmetries, occuring accidentally as low energy remnants from exact discrete symmetries. In such models, the axion and the further ALP are protected from disastrous explicit symmetry breaking effects due to Planck-scale suppressed operators. The scenarios considered exploit heavy right handed neutrinos getting their mass via PQ symmetry breaking and thus explain the small mass of the active neutrinos via a seesaw relation between the electroweak and an intermediate PQ symmetry breaking scale. We show some models that can accommodate simultaneously an axion dark matter candidate, an ALP explaining the anomalous transparency of the universe for $\gamma$-rays, and an ALP explaining the recently reported 3.55 keV gamma line from galaxies and clusters of galaxies, if the respective decay constants are of intermediate scale.

95 citations

Journal ArticleDOI
TL;DR: In this paper, a specific example based on the eclectic flavor group Ω ( 1 ) (a nontrivial combination of the traditional flavor group Δ ( 54 ) and the finite modular group T ′ ) is analyzed, and it is shown that this scheme is highly predictive since it severely restricts the possible group representations and modular weights of matter fields.

81 citations


Cited by
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[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Journal ArticleDOI
TL;DR: In this article, a Theta vacua of gauge theories is proposed for cosmologists. But the authors do not consider the cosmological perturbation theory of axions in string theory.
Abstract: 1 Introduction 2 Models: the QCD axion; the strong CP problem; PQWW, KSVZ, DFSZ; anomalies, instantons and the potential; couplings; axions in string theory 3 Production and IC's: SSB and non-perturbative physics; the axion field during inflation and PQ SSB; cosmological populations - decay of parent, topological defects, thermal production, vacuum realignment 4 The Cosmological Field: action; background evolution; misalignment for QCD axion and ALPs; cosmological perturbation theory - ic's, early time treatment, axion sound speed and Jeans scale, transfer functions and WDM; the Schrodinger picture; simualting axions; BEC 5 CMB and LSS: Primary anisotropies; matter power; combined constraints; Isocurvature and inflation 6 Galaxy Formation; halo mass function; high-z and the EOR; density profiles; the CDM small-scale crises 7 Accelerated expansion: the cc problem; axion inflation (natural and monodromy) 8 Gravitational interactions with black holes and pulsars 9 Non-gravitational interactions: stellar astrophysics; LSW; vacuum birefringence; axion forces; direct detection with ADMX and CASPEr; Axion decays; dark radiation; astrophysical magnetic fields; cosmological birefringence 10 Conclusions A Theta vacua of gauge theories B EFT for cosmologists C Friedmann equations D Cosmological fluids E Bayes Theorem and priors F Degeneracies and sampling G Sheth-Tormen HMF

1,282 citations

Journal ArticleDOI
TL;DR: In this article, a new upper bound on the photon-ALP coupling was derived based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field.
Abstract: We revise the bound from the supernova SN1987A on the coupling of ultralight axion-like particles (ALPs) to photons. In a core-collapse supernova, ALPs would be emitted via the Primakoff process, and eventually convert into gamma rays in the magnetic field of the Milky Way. The lack of a gamma-ray signal in the GRS instrument of the SMM satellite in coincidence with the observation of the neutrinos emitted from SN1987A therefore provides a strong bound on their coupling to photons. Due to the large uncertainty associated with the current bound, we revise this argument, based on state-of-the-art physical inputs both for the supernova models and for the Milky-Way magnetic field. Furthermore, we provide major amendments, such as the consistent treatment of nucleon-degeneracy effects and of the reduction of the nuclear masses in the hot and dense nuclear medium of the supernova. With these improvements, we obtain a new upper limit on the photon-ALP coupling: gaγ 5.3 × 10-12 GeV-1, for ma 4.4 × 10-10 eV, and we also give its dependence at larger ALP masses ma. Moreover, we discuss how much the Fermi-LAT satellite experiment could improve this bound, should a close-enough supernova explode in the near future.

337 citations

Journal ArticleDOI
TL;DR: In this paper, a review of axion-like particle detection is presented, focusing on the new experimental approaches and their complementarity, but also reviewing the most relevant recent results from the consolidated strategies and the prospects of new generation experiments under consideration in the field.
Abstract: Axions and other very light axion-like particles appear in many extensions of the Standard Model, and are leading candidates to compose part or all of the missing matter of the Universe. They also appear in models of inflation, dark radiation, or even dark energy, and could solve some long-standing astrophysical anomalies. The physics case of these particles has been considerably developed in recent years, and there are now useful guidelines and powerful motivations to attempt experimental detection. Admittedly, the lack of positive signal of new physics at the high energy frontier, and in underground detectors searching for weakly interacting massive particles, is also contributing to the increase of the interest in axion searches. The experimental landscape is rapidly evolving, with many novel detection concepts and new experiments being proposed lately. An updated account of those initiatives is lacking in the literature. In this review we attempt to provide such a review. We will focus on the new experimental approaches and their complementarity, but will also review the most relevant recent results from the consolidated strategies and the prospects of new generation experiments under consideration in the field. We will also briefly review the latest developments of the theory, cosmology and astrophysics of axions and we will discuss the prospects to probe a large fraction of relevant parameter space in the coming decade.

223 citations

Journal ArticleDOI
TL;DR: The landscape of QCD axion models is reviewed in this paper, where theoretical constructions that extend the window for the axion mass and couplings beyond conventional regions are highlighted and classified Bounds from cosmology, astrophysics and experimental searches are reexamined and updated

214 citations