Reconstructing realistic animal fur geometry from images is a challenging task due to the fine-scale details, self-occlusion, and view-dependent appearance of fur. In contrast to human hairstyle reconstruction, there are also no datasets that can be leveraged to learn a fur prior for different animals. In this work, we present a first multi-view-based method for high-fidelity 3D fur modeling of animals using a strand-based representation, leveraging the general knowledge of a vision language model. Given multi-view RGB images, we first reconstruct a coarse surface geometry using traditional multi-view stereo techniques. We then use a vision language model (VLM) system to retrieve information about the realistic length structure of the fur for each part of the body. We use this knowledge to construct the animal's furless geometry and grow strands atop it. The fur reconstruction is supervised with both geometric and photometric losses computed from multi-view images. To mitigate orientation ambiguities stemming from the Gabor filters that are applied to the input images, we additionally utilize the VLM to guide the strands' growth direction and their relation to the gravity vector th
The tactile sensation of stroking soft fur, known for its comfort and emotional benefits, has numerous applications in virtual reality, animal-assisted therapy, and household products. Previous studies have primarily utilized actual fur to present a voluminous fur experience that poses challenges concerning versatility and flexibility. In this study, we develop a system that integrates a head-mounted display with an ultrasound haptic display to provide visual and haptic feedback. Measurements taken using an artificial skin sheet reveal directional differences in tactile and visual responses to voluminous fur. Based on observations and measurements, we propose interactive models that dynamically adjust to hand movements, simulating fur-stroking sensations. Our experiments demonstrate that the proposed model using visual and haptic modalities significantly enhances the realism of a fur-stroking experience. Our findings suggest that the interactive visuo-haptic model offers a promising fur-stroking experience in virtual reality, potentially enhancing the user experience in therapeutic, entertainment, and retail applications.
The creation of cinematic-quality animal effects necessitates the precise modeling of muscle and fur dynamics, a process that remains both labor-intensive and computationally expensive within traditional production workflows. While generative diffusion models have shown promise in diverse artistic workflows, their capacity for high-fidelity animal simulation remains largely unexploited. We present MoZoo, a generative dynamics solver that bypasses conventional refinement to synthesize high-fidelity animal videos from coarse meshes under multimodal guidance. We propose Role-Aware RoPE (RAR-RoPE) which employs role-based index remapping to synchronize motion alignment while decoupling reference information via fixed temporal offsets. Complementing this, Asymmetric Decoupled Attention partitions the latent sequence to enforce a unidirectional information flow, effectively preventing feature interference and improving computational efficiency. To address the scarcity of high-quality training data, we introduce MoZoo-Data, a synthetic-to-real pipeline that leverages a rendering engine and an inverse mapping approach to construct a large-scale dataset of paired sequences. Furthermore, we
Modern, data-driven medical research requires the processing of sensitive health data on a large scale. However, this data is subject to special protection under the GDPR, which is why processing regularly raises data protection concerns in practice. These concerns are particularly prevalent when sensitive personal data is processed without informed consent. This article analyses options for data processing in the field of medical research without consent and describes the legal framework for anonymisation under the GDPR, the national Austrian implementation of the research exemption, and their interaction. -- Moderne, datengetriebene medizinische Forschung erfordert die Verarbeitung sensibler Gesundheitsdaten in grossem Ausmass. Diese sind im System der DSGVO jedoch besonders geschützt, weswegen einer rechtssicheren Verarbeitung in der Praxis regelmässig datenschutzrechtliche Bedenken entgegenstehen. Diese Bedenken bestehen insbesondere bei Verarbeitung sensibler personenbezogener Daten ohne informierte Einwilligung. Dieser Beitrag analysiert daher Möglichkeiten zur Datenverarbeitung im Bereich der medizinischen Forschung fernab der Einwilligung und beschreibt hierfür das rechtlic
This study presents the first ex-vivo positronium imaging of human tissues using the modular J-PET scanner with the $^{44}$Sc radionuclide. The $^{44}$Sc isotope was produced via the $^{44}$Ca(p, n)$^{44}$Sc nuclear reaction and used to perform positronium imaging of phantom composed of human adipose tissue, cardiac myxoma tissue, thrombi blood clot, and also porous polymer XAD4, and a certified reference material (CRM) made from fused silica. The experiment demonstrates the suitability of $^{44}$Sc as a positron source for positronium imaging. The performance of J-PET for positronium imaging with $^{44}$Sc was validated by proper reconstruction of the mean orthopositronium lifetime for CRM material and XAD-4 polymer. The mean ortho-positronium (oPs) lifetimes determined for adipose tissue, cardiac myxoma tissues and thrombi were consistent with results of previous experiments. The study highlights the potential $^{44}$Sc radionuclide for positronium lifetime imaging (PLI).
Quantum technologies in the terahertz (THz) require a coherent interface between addressable qubits and THz quantum channels -- a capacity that so far, remains largely underdeveloped. Here, we propose and demonstrate the generation of steady-state entanglement between polar quantum emitters, mediated by THz photons. We exploit strong visible-light driving of the emitters to create Rabi-split dressed eigenstates whose energy separation can be optically tuned into the THz regime. The polar nature of the emitters activates THz transitions within these eigenstates, allowing them to couple to a THz photonic mode that induces collective dissipative dynamics. A coherent driving and control of these effective THz emitters is achieved by using a sideband optical drive with detuning close to the THz transition frequency. The resulting interplay of collective dissipation and driving activates a mechanism to generate steady-state entanglement with high values of the concurrence ($C>0.9$), attainable under experimentally feasible parameters. Crucially, both coherent manipulation and quantum state tomography are implemented entirely through optical means, avoiding direct THz control and detec
Quantum error detection can produce unbiased expectation values that exponentially converge to noiseless results as the code distance is increased. Despite this, its performance as an error mitigation technique is relatively understudied on quantum hardware because of its two main drawbacks: (i) the number of samples increases exponentially in the circuit depth/noise level, and (ii) the classical processing generally grows exponentially in the code distance, though exceptions exist. Additionally, the constant (but often large) overhead of embedding the code and logical operations on hardware can make accuracy worse instead of better. In this work, we seek to provide a clear picture of these opportunities and challenges for scaling quantum error detection on hardware. We do so by performing a detailed benchmarking study on real and simulated noisy quantum computers, using the repetition code and triangular color code for memory experiments and logical computations with up to $74$ physical qubits. In addition to these benchmarks, we estimate the pseudothreshold of codes to map the frontier of error detection on current and future quantum computers. Despite the challenges, our results
The spin-S Heisenberg antiferromagnet on the two-dimensional lattice is investigated for S=1/2 and S=1. We consider interaction at isolated dimers ($J_{\rm d}$) and interaction bonds that form the bounce lattice ($J_{\rm b}$). For $J_{\rm d}=J_{\rm b}$, the system is reduced to the maple-leaf-lattice antiferromagnet. We primarily conduct highly parallelized numerical diagonalization to examine the spin excitation gap above the ground state for various $J_{\rm b}/J_{\rm d}$ cases. For S=1/2, we report calculations for a 42-site cluster that has not been previously treated. The S=1 case is examined for the first time for clusters up to 24 sites. Regardless of whether S=1/2 or 1, we find that the system has a gapped nature for small $J_{\rm d}/J_{\rm b}$ and becomes gapless at $J_{\rm d}/J_{\rm b}\sim 1.4$. For S=1, we also find that another gapped region appears between the gapless case at $J_{\rm d}/J_{\rm b}\sim 1.4$ and the boundary of the exact-dimer phase.
The Beginners Lab Course in Physics is scheduled very early in the course of studies not only for students of physics but also for students for which physics is a minor subject. We provide all partipants with several auxilliary materials for the preparation of the experiments and for writing a protocol. In our study, we enlighten the effect of the usage of these materials on the success of passing the lab course. ----- Das Anfängerpraktikum Physik ist eine früh im Studienverlauf stattfindende Veranstaltung sowohl für Hauptfachstudierende Physik, alsauch für Studierende mit Nebenfach Physik. Die vorliegende Untersuchung beleuchtet den Effekt der Verwendung von Hilfsmitteln zur Versuchsvorbereitung und Protokollierung auf das erfolgreiche Bestehen des Praktikums.
In this paper, we establish local well-posedness for the Cauchy problem associated with the Korteweg-de Vries (KdV) equation on a general metric star graph. The graph comprises m + k semi-infinite edges: k negative half-lines and m positive half-lines, all joined at a common vertex. The choice of boundary conditions is compatible with the conditions determined by the semigroup theory. The crucial point in this work is to obtain the integral formula using the forcing operator method and the Fourier restriction method of Bourgain. This work extends the results obtained by Cavalcante for the specific case of the Y junction to a more general class of star graphs.
We present an optomechanical device platform for characterization of optical, thermal, and rheological properties of fluids on the micron scale. A suspended silicon microdisk resonator with a vibrating mass of 100 fg and an effective measurement volume of less than a pL is used to monitor properties of different fluids at rest. By employing analytical models for thermo-optical effects, thermal diffusion and fluid-structure interactions, our platform determines the refractive index, thermal conductivity, viscosity, density and compressibility of the fluid, in a compact measurement setup. A single measurement takes as short as 70 microseconds, and the employed power can be less than 100 microwatts, guaranteeing measurement at rest and in thermal equilibrium.
[Translation of and Commentary on Léon Rosenfeld's "Ueber die Gravitationwirkungen des Lichtes", Zeitschrift fur Physik 65: 589-599 (1930). Originally published in German. Submitted for publication on September 26, 1930. See [1] in the Comments with References section before reading this English translation.] The gravitational field generated by an electromagnetic field is calculated using of laws of quantum mechanics and it is shown that the resulting gravitational energy turns out to be infinitely large, raising a new difficulty for the Heisenberg-Pauli quantum theory of wave fields. In addition, the transition processes in first-order approximation involving light and gravitational quanta are briefly discussed.
We investigate the non-linear evolution of Baryon Acoustic Oscillations (BAO) in the low-redshift matter power spectrum from the DEUS-FUR $Λ$CDM model simulation. This is the first cosmological N-body simulation encompassing the full observable cosmic volume, thus allowing cosmic variance limited predictions at BAO scales. We control the effect of numerical systematic errors using a series of large volume high-resolution simulations. The combined analysis allows us to measure the matter power spectrum between $z=0$ and $1$ to 1% over the entire BAO range, $0.03<k [\textrm{h Mpc}^{-1}]<0.3$, in bins of size $Δk/k\lesssim$ 1%. We define the BAO with respect to a non-linearly evolved wiggle-free spectrum and determine the characteristics of the BAO without recurring to extrapolation from global fitting functions. We quantify the effects of non-linearities on the position and amplitude of the BAO extrema, and the coupling to the broadband slope of the power spectrum. We use these estimates to test non-linear predictions from semi-analytical models. Quite remarkably from the analysis of the redshift evolution of BAO we find that the second dip and third peak remains unaltered by n
Sampling graphs is an important task in data mining. In this paper, we describe Little Ball of Fur a Python library that includes more than twenty graph sampling algorithms. Our goal is to make node, edge, and exploration-based network sampling techniques accessible to a large number of professionals, researchers, and students in a single streamlined framework. We created this framework with a focus on a coherent application public interface which has a convenient design, generic input data requirements, and reasonable baseline settings of algorithms. Here we overview these design foundations of the framework in detail with illustrative code snippets. We show the practical usability of the library by estimating various global statistics of social networks and web graphs. Experiments demonstrate that Little Ball of Fur can speed up node and whole graph embedding techniques considerably with mildly deteriorating the predictive value of distilled features.
Observations of colliding galaxy clusters with high relative velocity probe the tail of the halo pairwise velocity distribution with the potential of providing a powerful test of cosmology. As an example it has been argued that the discovery of the Bullet Cluster challenges standard $Λ$CDM model predictions. Halo catalogs from N-body simulations have been used to estimate the probability of Bullet-like clusters. However, due to simulation volume effects previous studies had to rely on a Gaussian extrapolation of the pairwise velocity distribution to high velocities. Here, we perform a detail analysis using the halo catalogs from the Dark Energy Universe Simulation Full Universe Runs (DEUS-FUR), which enables us to resolve the high-velocity tail of the distribution and study its dependence on the halo mass definition, redshift and cosmology. Building upon these results we estimate the probability of Bullet-like systems in the framework of Extreme Value Statistics. We show that the tail of extreme pairwise velocities significantly deviates from that of a Gaussian, moreover it carries an imprint of the underlying cosmology. We find the Bullet Cluster probability to be two orders of ma
In this manuscript, we describe a scientific device specifically designed for the study of the plasticity fluctuations preceding the fracture of granular media. Biaxial tests on model granular media are performed using a commercial uniaxial loading system. Strain field fluctuations are measured using a method based on the interference of coherent light scattered by the sample. We show that such a device enables discrete plasticity events to be unambiguously evidenced. Moreover, those discrete plasticity fluctuations depend only on the imposed strain, and not on the strain rate.
Bounds are derived on the axion-like particle (ALP) to two-photon coupling in the mass range $2.65-5.27$ eV. The bounds are obtained by searching for the signal from ALP decay in the Multi Unit Spectroscopic Explorer (MUSE) observations of five dwarf spheroidal galaxies, under the assumption that ALPs constitute the dark matter component of the haloes. These bounds are of the same order and improve on the robustness of those of Reference~\cite{Regis}, and currently represent the strongest bounds within the considered mass range.
Generally a central role has been assigned to an unavoidable physical interaction between the measuring instrument and the physical entity measured in the change in the wave function that often occurs in measurement in quantum mechanics. A survey of textbooks on quantum mechanics by authors such as Dicke and Witke (1960), Eisberg and Resnick (1985), Gasiorowicz (1974), Goswami (1992), and Liboff (1993) supports this point. Furthermore, in line with the view of Bohr and Feynman, generally the unavoidable interaction between a measuring instrument and the physical entity measured is considered responsible for the uncertainty principle. A gedankenexperiment using Feynman's double-hole interference scenario shows that physical interaction is not necessary to effect the change in the wave function that occurs in measurement in quantum mechanics. Instead, the general case is that knowledge is linked to the change in the wave function, not a physical interaction between the physical existent measured and the measuring instrument. Empirical work on electron shelving that involves null measurements, or what Renninger called negative observations (Zeitschrift fur Physik, vol. 158, p. 417), s
It is argued that the conclusions obtained by Renninger (Zeitschrift fur Physik 136, 251 (1953)), by means of an interferometer thought experiment, have important implications for a number of still ongoing discussions about quantum mechanics (QM). To these belong the ontology underlying QM, Bohr's complementarity principle, the significance of QM's wave function, the "elements of reality" introduced by Einstein, Podolsky and Rosen (EPR), and Bohm's version of QM (BQM). A slightly extended setup is used to make a physical prediction at variance with the mathematical prediction of QM. An english translation of Renninger's paper, which was originally published in german language, follows the present paper. This should facilitate access to that remarkable, apparently overlooked and forgotten, paper.
In the fall of 1924, Enrico Fermi visited Paul Ehrenfest at Leyden on a 3-month fellowship from the International Education Board (IEB). Fermi was 23 years old. In his trip report to the IEB, Fermi says he learned a lot about cryogenics and worked on two scientific papers, including the following one. It was submitted in German to Zeitschrift fur Physik. The German version was known to Weizsacker and Williams and cited in the papers (10 years) later in which they extended Fermi's method to the Ultra-Relativistic case. The German version was subsequently translated into a Russian version and perhaps other languages. Fermi's Italian version (printed in Nuovo Cimento) is less widely known and does not appear in the ``Collected Works''. Nevertheless, Persico remarks that this was one of Fermi's favorite ideas and that he often used it in later life. So, we would like to think of this as a late 100th birthday present to the Italian Navigator. We would like to thank Professor T.D. Lee for his encouragement of this project and for interesting discussions about Fermi. Also Tom Rosenblum at the Rockefeller Archives for bringing Fermi's correspondence to our attention and Bonnie Sherwood for