Tootfinder

Heute vor 16 Jahren: Am 25. Mai 2009 führte #Nordkorea seinen 2. #Atomtest durch. Die Explosion hatte etwa ein Drittel der Sprengkraft der Hiroshima-Bombe mit einer geschätzten Stärke von 2,35 Kilotonnen. Der Test löste weltweite Verurteilungen und schärfere UN-Sanktionen aus.

On the solvability of some systems of quadratic integral equations in dimensions two and three
Vitali Vougalter
https://arxiv.org/abs/2506.15069 https://…

On the solvability of some systems of quadratic integral equations in dimensions two and three
The work deals with the existence of solutions of a certain system of quadratic integral equations in H^2(R^d,R^N), d = 2, 3. We demonstrate the existence of a perturbed solution by virtue of a fixed point technique.

Quadratic Extended and Unscented Kalman Filter Updates
Simone Servadio, Chiran Cherian
https://arxiv.org/abs/2506.06256 https://arxiv…

Quadratic Extended and Unscented Kalman Filter Updates
Common filters are usually based on the linear approximation of the optimal minimum mean square error estimator. The Extended and Unscented Kalman Filters handle nonlinearity through linearization and unscented transformation, respectively, but remain linear estimators, meaning that the state estimate is a linear function of the measurement. This paper proposes a quadratic approximation of the optimal estimator, creating the Quadratic Extended and Quadratic Unscented Kalman Filter. These retain…

This https://arxiv.org/abs/2407.19995 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_qfi…

Consumption-investment optimization with Epstein-Zin utility in unbounded non-Markovian markets
The paper investigates the consumption-investment problem for an investor with Epstein-Zin utility in an incomplete market. A non-Markovian environment with unbounded parameters is considered, which is more realistic in practical financial scenarios compared to the Markovian setting. The optimal consumption and investment strategies are derived using the martingale optimal principle and quadratic backward stochastic differential equations (BSDEs) whose solutions admit some exponential moment. T…

Gauges for quadratic gravity: the extended transverse gauge and the energy-momentum tensor of the massive spin-2 field
Matheus F. S. Alves, L. G. Medeiros, Davi C. Rodrigues
https://arxiv.org/abs/2506.10793

Gauges for quadratic gravity: the extended transverse gauge and the energy-momentum tensor of the massive spin-2 field
We study the 4D Einstein-Hilbert action extension based on the square of the curvature tensors. Analyses of gauge and perturbation modes are often done considering the Teyssandier gauge condition. Although this approach can be useful for other higher-order extensions of quadratic gravity, a generalized transverse (or Lorentz) gauge is clear and sufficient for the present case, as explained here. We provide a detailed analysis of the generalized transverse gauge condition, its residual gauge sym…

Gaps between quadratic forms
Siddharth Iyer
https://arxiv.org/abs/2505.23428 https://arxiv.org/pdf/2505.23428

Gaps between quadratic forms
Let $\triangle$ denote the integers represented by the quadratic form $x^2+xy+y^2$ and $\square_{2}$ denote the numbers represented as a sum of two squares. For a non-zero integer $a$, let $S(\triangle,\square_{2},a)$ be the set of integers $n$ such that $n \in \triangle$, and $n + a \in \square_{2}$. We conduct a census of $S(\triangle,\square_{2},a)$ in short intervals by showing that there exists a constant $H_{a} > 0$ with \begin{align*} \# S(\triangle,\square_{2},a)\cap [x,x+H_{a}\cdot x^{…

Resonant dynamics of dipole-conserving Bose-Hubbard model with time-dependent tensor electric fields
Jiali Zhang, Shaoliang Zhang
https://arxiv.org/abs/2506.13159

Resonant dynamics of dipole-conserving Bose-Hubbard model with time-dependent tensor electric fields
Recently, tensor gauge fields and their coupling to fracton phases of matter have attracted more and more research interest, and a series of novel quantum phenomena arising from the coupling has been predicted. In this article, we propose a theoretical scheme to construct a time-dependent rank-2 tensor electric field by introducing a periodically driving quadratic potential in a dipole-conserving Bose-Hubbard model, and investigate the dynamics of dipole and fracton excitations when the drive f…

This https://arxiv.org/abs/2503.13965 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

First-Order Projected Algorithms With the Same Linear Convergence Rate Bounds as Their Unconstrained Counterparts
In this paper, we propose a systematic approach for constructing first-order projected algorithms for optimization problems with general set constraints, building upon their unconstrained counterparts. We show that these projected algorithms retain the same linear convergence rate bounds, when the latter are obtained for the unconstrained algorithms via quadratic Lyapunov functions arising from integral quadratic constraint (IQC) characterizations. The projected algorithms are constructed by ap…

This https://arxiv.org/abs/2506.02450 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

Muon (and Lepton) Anomalous Magnetic Moments and Limits on Their Radii
The limits on lepton radii and contact interaction scales are used to derive limits on the deviations of lepton anomalous magnetic dipole moments (g-2)/2 from the Standard Model predictions. In the case of quadratic dependence of the deviations on the lepton mass the limits for electrons are better compared to low energy measurements, for muons somewhat weaker than the latest precision experiments, and for taus by far the best.

Solvability of the Korteweg-de Vries equation under meromorphic initial conditions by quadrature
Kazuyuki Yagasaki
https://arxiv.org/abs/2506.08046 https:/…

Solvability of the Korteweg-de Vries equation under meromorphic initial conditions by quadrature
We study the solvability of the Korteweg-de Vries equation under meromorphic initial conditions by quadrature when the inverse scattering transform (IST) is applied. It is a key to solve the Schrödinger equation appearing in the Lax pair in application of the IST. We show that the Schrödinger equation is always integrable in the sense of differential Galois theory, i.e., solvable by quadrature, if and only if the meromporphic potential is reflectionless, under the condition that the potential…