Tootfinder

Interesting. That new Fuji camera blew up all over social media, to the point where I couldn't avoid it. However, I really like what they are doing with the film presets. Sometimes it's great to have a fast way to get to the place you want to go, and as a totally inexperienced photographer I think it would be a confidence builder.
From: @…@…

Fujifilm X100VI vs. Ricoh GR IIIx: battle for the best point-and-shoot
The $1,599.00 FujiFilm X100VI and the $1,049.95 Ricoh GR IIIx both come in a small package and have an APS-C sensor and a fixed focal length lens that can produce crisp images. So, which one reigns supreme?

„Die #Grünen sind an allem schuld“ – klar dachte ich, schon das Sprichwort sagt: wer nichts macht, macht keine Fehler. Doch dann mußte ich an die #FDP denken…

A simple prediction of the non-linear matter power spectrum in Brans-Dicke gravity from linear theory
Herman Sletmoen, Hans A. Winther
https://arxiv.org/abs/2403.03786

A simple prediction of the non-linear matter power spectrum in Brans-Dicke gravity from linear theory
Brans-Dicke (BD) was one of the first proposed scalar-tensor theories of gravity, and effectively turns the gravitational constant of General Relativity (GR) time-dependent. Constraints on the BD parameter $ω$ serve as a benchmark for testing GR, which is recovered in the limit $ω\rightarrow \infty$. Current small-scale astrophysical constraints $ω\gtrsim 10^5$ are much tighter than large-scale cosmological constraints $ω\gtrsim 10^3$, but these decouple if the true theory of gravity featur…

The new concepts of ether and calculation of the cosmological constant
Xiao-Song Wang
https://arxiv.org/abs/2403.05582 https://arxiv.…

The new concepts of ether and calculation of the cosmological constant
Since the general theory of relativity (GR) meets some difficulties, it seems that new considerations on the ether theories of gravitation in the history are needed. A theory of gravity based on some new concepts of ether and particles is briefly reviewed. In this theory, the universe is filled with a kind of fluid which may be called the $Ω(0)$ substratum, or we say the gravitational ether. Particles are modeled as sink flows in the $Ω(0)$ substratum. Newton's law of gravitation is derived b…

Towards homological projective duality for $\mathrm{Gr}(2, 2n)$
Dmitrii Pirozhkov
https://arxiv.org/abs/2402.14754 https://arxiv.org/…

Towards homological projective duality for $\mathrm{Gr}(2, 2n)$
Consider a Grassmannian $\mathrm{Gr}(2, V)$ for an even-dimensional vector space $V$. Its derived category of coherent sheaves has a Lefschetz exceptional collection with respect to the Plücker embedding. We consider a variety $X_1$ of pairs consisting of a degenerate $2$-form on $V$ and a line in its kernel. Note that $X_1$ is generically a $\mathbb{P}^1$-fibration over the Pfaffian variety of degenerate $2$-forms on $V$. We construct an exceptional collection of coherent sheaves on $X_1$ suc…

„Die #Grünen sind an allem schuld“ – klar dachte ich, schon das Sprichwort sagt: wer nichts macht, macht keine Fehler. Doch dann mußte ich an die #FDP denken…

Optimal E-Values for Exponential Families: the Simple Case
Peter Gr\"unwald, Tyron Lardy, Yunda Hao, Shaul K. Bar-Lev, Martijn de Jong
https://arxiv.org/abs/2404.19465

Optimal E-Values for Exponential Families: the Simple Case
We provide a general condition under which e-variables in the form of a simple-vs.-simple likelihood ratio exist when the null hypothesis is a composite, multivariate exponential family. Such `simple' e-variables are easy to compute and expected-log-optimal with respect to any stopping time. Simple e-variables were previously only known to exist in quite specific settings, but we offer a unifying theorem on their existence for testing exponential families. We start with a simple alternative $Q$…

Numerical Relativity Multimodal Waveforms using Absorbing Boundary Conditions
Luisa T. Buchman, Matthew D. Duez, Marlo Morales, Mark A. Scheel, Tim M. Kostersitz, Andrew M. Evans
https://arxiv.org/abs/2402.12544

Numerical Relativity Multimodal Waveforms using Absorbing Boundary Conditions
Errors due to imperfect boundary conditions in numerical relativity simulations of binary black holes can produce unphysical reflections of gravitational waves which compromise the accuracy of waveform predictions, especially for subdominant modes. A system of higher order absorbing boundary conditions which greatly reduces this problem was introduced in earlier work [arXiv:gr-qc/0608051]. In this paper, we devise two new implementations of this boundary condition system in the Spectral Einstei…

Estimation of the invariant measure of a multidimensional diffusion from noisy observations
Rapha\"el Maillet, Gr\'egoire Szymanski
https://arxiv.org/abs/2404.12181

Estimation of the invariant measure of a multidimensional diffusion from noisy observations
We introduce a new approach for estimating the invariant density of a multidimensional diffusion when dealing with high-frequency observations blurred by independent noises. We consider the intermediate regime, where observations occur at discrete time instances $kΔ_n$ for $k=0,\dots,n$, under the conditions $Δ_n\to 0$ and $nΔ_n\to\infty$. Our methodology involves the construction of a kernel density estimator that uses a pre-averaging technique to proficiently remove noise from the data whi…