Yuta Hamada
YOU?
Author Swipe
View article: Revisiting constraints on magnetogenesis from baryon asymmetry
Revisiting constraints on magnetogenesis from baryon asymmetry Open
Magnetic fields in the universe potentially serve as a messenger of primordial physics. The observationally suggested intergalactic magnetic fields may be a relic of helical primordial $\mathrm{U}(1)_Y$ magnetic fields, which may also expl…
View article: Inflation models selected by the swampland distance conjecture with the Lyth bound
Inflation models selected by the swampland distance conjecture with the Lyth bound Open
We investigate the extent to which the Swampland Conjecture can be employed to constrain large-field inflationary models from the perspective of quantum gravity consistency. In particular, we focus on the Swampland Distance Conjecture, whi…
View article: Symmetries of Hot SM, Magnetic Flux & Baryogenesis from Helicity Decay
Symmetries of Hot SM, Magnetic Flux & Baryogenesis from Helicity Decay Open
We revisit the electroweak crossover of the Standard Model (SM) in the early Universe, focusing on the interplay between generalized global symmetries, magnetic flux dynamics, and baryogenesis. Employing the dimensionally reduced 3d effect…
View article: More on 8d non-supersymmetric branes and heterotic strings
More on 8d non-supersymmetric branes and heterotic strings Open
We determine the maximal gauge groups arising in $E_8$ heterotic string theory on $T^2$. Our analysis proceeds along two approaches. First, we start the moduli space of the supersymmetric heterotic string theory on $T^2$ focusing on points…
View article: Investigating 9d/8d non-supersymmetric branes and theories from supersymmetric heterotic strings
Investigating 9d/8d non-supersymmetric branes and theories from supersymmetric heterotic strings Open
A bstract We consider heterotic string theories in nine and eight dimensions. We identify the disconnected part of the spacetime gauge group by studying the outer automorphism of the charge lattices. The absence of the global symmetry indi…
View article: Swampland bounds on magnetized extra dimensions
Swampland bounds on magnetized extra dimensions Open
A bstract We consider a six-dimensional U(1) gauge theory compactified on two-dimensional manifolds. The number of chiral fermions is determined by the flux quantization number on the two-dimensional compact manifolds. Using the Swampland …
View article: Black String in the Standard Model
Black String in the Standard Model Open
The Swampland cobordism conjecture predicts various new objects in a theory with dynamical gravity. Applying this idea to the Standard Model of particle physics, a string object is predicted. We numerically constructed such an object as a …
View article: Enumerating 6D supergravities with T ≤ 1
Enumerating 6D supergravities with T ≤ 1 Open
A bstract The space of 6D supergravities with minimal supersymmetry is greatly constrained by anomaly cancellation. Nevertheless, a large number of models satisfy all low-energy consistency conditions and in this work we make progress towa…
View article: Investigating 9d/8d non-supersymmetric branes and theories from supersymmetric heterotic strings
Investigating 9d/8d non-supersymmetric branes and theories from supersymmetric heterotic strings Open
We consider heterotic string theories in nine and eight dimensions. We identify the disconnected part of the spacetime gauge group by studying the outer automorphism of the charge lattices. The absence of the global symmetry indicates the …
View article: Swampland Bounds on Magnetized Extra Dimensions
Swampland Bounds on Magnetized Extra Dimensions Open
We consider a six-dimensional $U(1)$ gauge theory compactified on two-dimensional manifolds. The number of chiral fermions is determined by the flux quantization number on the two-dimensional compact manifolds. Using the Swampland Conjectu…
View article: On the string landscape without hypermultiplets
On the string landscape without hypermultiplets Open
A bstract In this work we study interesting corners of the quantum gravity landscape with 8 supercharges pushing the boundaries of our current understanding. Calabi-Yau threefolds compactifications of F/M/type II theories to 6, 5 and 4 dim…
View article: Enumerating 6D supergravities with $T\leq 1$
Enumerating 6D supergravities with $T\leq 1$ Open
The space of 6D supergravities with minimal supersymmetry is greatly constrained by anomaly cancellation. Nevertheless, a large number of models satisfy all low-energy consistency conditions and in this work we make progress towards exhaus…
View article: Towards a complete classification of 6D supergravities
Towards a complete classification of 6D supergravities Open
A bstract The constraints arising from anomaly cancellation are particular strong for chiral theories in six dimensions. We make progress towards a complete classification of 6D supergravities with minimal supersymmetry and non-abelian gau…
View article: Dualities from Swampland principles
Dualities from Swampland principles Open
A bstract We initiate the program of bottom-up derivation of string theory dualities using Swampland principles. In particular, we clarify the relation between Swampland arguments and all the string theory dualities in d ≥ 9 dimensional su…
View article: Towards a complete classification of 6D supergravities
Towards a complete classification of 6D supergravities Open
The constraints arising from anomaly cancellation are particular strong for chiral theories in six dimensions. We make progress towards a complete classification of 6D supergravities with minimal supersymmetry and non-abelian gauge group. …
View article: On the String Landscape Without Hypermultiplets
On the String Landscape Without Hypermultiplets Open
In this work we study interesting corners of the quantum gravity landscape with 8 supercharges pushing the boundaries of our current understanding. Calabi-Yau threefolds compactifications of F/M/type II theories to 6, 5 and 4 dimensions ar…
View article: Flavor hierarchy from smooth confinement
Flavor hierarchy from smooth confinement Open
We present a model to explain the Standard Model flavor hierarchy. Our model is based on explicit smooth confinement (namely confinement without chiral symmetry breaking in a supersymmetric gauge theory) at an intermediate energy scale, be…
View article: On brane gaugino condensates in 10d
On brane gaugino condensates in 10d Open
We analyze the structure of gaugino interactions on D7-branes from a 10d perspective. This is essential if one wants to lift the standard 4d approach to type IIB moduli stabilization to 10d. In particular, a 10d picture has recently been u…
View article: Understanding KKLT from a 10d perspective
Understanding KKLT from a 10d perspective Open
Some of the most well-celebrated constructions of metastable de Sitter vacua from string theory, such as the KKLT proposal, involve the interplay of gaugino condensation on a D7-brane stack and an uplift by a positive tension object. These…
View article: On (scalar QED) gravitational positivity bounds
On (scalar QED) gravitational positivity bounds Open
A bstract We study positivity bounds in the presence of gravity. We first review the gravitational positivity bound at the tree-level, where it is known that a certain amount of negativity is allowed for the coefficients of higher-derivati…
View article: Dualities from Swampland principles
Dualities from Swampland principles Open
We initiate the program of bottom-up derivation of string theory dualities using Swampland principles. In particular, we clarify the relation between Swampland arguments and all the string theory dualities in $d\geq9$ dimensional supersymm…
View article: On (Scalar QED) Gravitational Positivity Bounds
On (Scalar QED) Gravitational Positivity Bounds Open
We study positivity bounds in the presence of gravity. We first review the gravitational positivity bound at the tree-level, where it is known that a certain amount of negativity is allowed for the coefficients of higher-derivative operato…
View article: Baby universes in 2d and 4d theories of quantum gravity
Baby universes in 2d and 4d theories of quantum gravity Open
A bstract The validity of the Coleman mechanism, which automatically tunes the fundamental constants, is examined in two-dimensional and four-dimensional quantum gravity theories. First, we consider two-dimensional Euclidean quantum gravit…
View article: Design and Fabrication of Mature Engineered Pre-Cardiac Tissue Utilizing 3D Bioprinting Technology and Enzymatically Crosslinking Hydrogel
Design and Fabrication of Mature Engineered Pre-Cardiac Tissue Utilizing 3D Bioprinting Technology and Enzymatically Crosslinking Hydrogel Open
The fabrication of mature engineered cardiac tissue is one of the major challenges in cardiac tissue engineering. For this purpose, we attempted to apply the 3D bioprinting approach. Aiming to construct an oriented tissue, a fine fiber-sha…
View article: Baby universes in 2d and 4d theories of quantum gravity
Baby universes in 2d and 4d theories of quantum gravity Open
The validity of the Coleman mechanism, which automatically tunes the fundamental constants, is examined in two-dimensional and four-dimensional quantum gravity theories. First, we consider two-dimensional Euclidean quantum gravity on orien…
View article: Flavor Hierarchy from Smooth Confinement
Flavor Hierarchy from Smooth Confinement Open
We present a model to explain the Standard Model flavor hierarchy. Our model is based on explicit smooth confinement (namely confinement without chiral symmetry breaking in a supersymmetric gauge theory) at an intermediate energy scale, be…
View article: Finiteness and the swampland
Finiteness and the swampland Open
We view and provide further evidence for a number of swampland criteria, including the weak gravity conjecture, distance conjecture and bounds on the finiteness of the quantum gravity vacua from the prism of the finiteness of black hole en…
View article: Compactness of brane moduli and the String Lamppost Principle in d > 6
Compactness of brane moduli and the String Lamppost Principle in d > 6 Open
A bstract We demonstrate the validity of the String Lamppost Principle — that all consistent theories of quantum gravity are in the String Landscape — for supersymmetric theories in d > 6 using compactness and connectedness of the moduli s…