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Continuing our program of deriving aspects of celestial holography from string theory, we extend the Roiban-Spradlin-Volovich-Witten (RSVW) formalism to celestial amplitudes. We reformulate the tree-level maximally-helicity-violating (MHV) celestial leaf amplitudes for gluons in $\mathcal{N}=4$ supersymmetric Yang-Mills (SYM) theory and for gravitons in $\mathcal{N}=8$ Supergravity in terms of minitwistor wavefunctions. These are defined as representatives of cohomology classes on the minitwistor space $\mathbf{MT}$, associated to the three-dimensional Euclidean anti-de Sitter space. In this framework, celestial leaf amplitudes are expressed as integrals over the moduli space of minitwistor lines. We construct a minitwistor generating functional for MHV leaf amplitudes using the Quillen determinant line bundle, extending the approach originally developed by Boels, Mason and Skinner. Building on this formalism, we propose supersymmetric celestial conformal field theories (CFTs) as $\sigma$-models, where the worldsheet is given by the celestial supersphere $\mathbf{CP}^{1|2}$, and the target space is the minitwistor superspace $\mathbf{MT}^{2|\mathcal{N}}$. We demonstrate that the semiclassical effective action of these $\sigma$-models reproduces the MHV gluonic and gravitational leaf amplitudes in $\mathcal{N}=4$ SYM theory and $\mathcal{N}=8$ Supergravity. This construction provides a concrete realisation of the supersymmetric celestial CFT framework recently introduced by Tropper (2024)., Comment: 62 pages, Version 3: I corrected typographical issues in Subsections II.2 and II.3

The superior soft tissue differentiation provided by MRI may enable more accurate tumor segmentation compared to CT and PET, potentially enhancing adaptive radiotherapy treatment planning. The Head and Neck Tumor Segmentation for MR-Guided Applications challenge (HNTSMRG-24) comprises two tasks: segmentation of primary gross tumor volume (GTVp) and metastatic lymph nodes (GTVn) on T2-weighted MRI volumes obtained at (1) pre-radiotherapy (pre-RT) and (2) mid-radiotherapy (mid-RT). The training dataset consists of data from 150 patients, including MRI volumes of pre-RT, mid-RT, and pre-RT registered to the corresponding mid-RT volumes. Each MRI volume is accompanied by a label mask, generated by merging independent annotations from a minimum of three experts. For both tasks, we propose adopting the nnU-Net V2 framework by the use of a 15-fold cross-validation ensemble instead of the standard number of 5 folds for increased robustness and variability. For pre-RT segmentation, we augmented the initial training data (150 pre-RT volumes and masks) with the corresponding mid-RT data. For mid-RT segmentation, we opted for a three-channel input, which, in addition to the mid-RT MRI volume, comprises the registered pre-RT MRI volume and the corresponding mask. The mean of the aggregated Dice Similarity Coefficient for GTVp and GTVn is computed on a blind test set and determines the quality of the proposed methods. These metrics determine the final ranking of methods for both tasks separately. The final blind testing (50 patients) of the methods proposed by our team, RUG_UMCG, resulted in an aggregated Dice Similarity Coefficient of 0.81 (0.77 for GTVp and 0.85 for GTVn) for Task 1 and 0.70 (0.54 for GTVp and 0.86 for GTVn) for Task 2.

We propose a generalisation of the Wess-Zumino-Novikov-Witten (WZNW) model, formulated on a holomorphic extension of supersymmetric three-dimensional Anti-de Sitter $\left(AdS_{3}\right)$ space, which holographically reproduces the tree-level maximally-helicity-violating (MHV) celestial amplitudes for gravitons in $\mathcal{N}=8$ supergravity and gluons in four-dimensional $\mathcal{N}=4$ supersymmetric Yang-Mills (SYM) theory., Comment: 33 pp

Interferometry has underpinned a century of discoveries, ranging from the disproval of the ether theory to the detection of gravitational waves, offering insights into wave dynamics with unrivalled precision through the measurement of phase relationships. In electronics, phase-sensitive measurements can probe the nature of transmissive topological and quantum states, but are only possible using complex device structures in magnetic fields. Here we demonstrate electronic interferometry in a single-molecule device through the study of non-equilibrium Fano resonances. We show the phase difference between an electronic orbital and a coupled Fabry-Perot resonance are tuneable through electric fields, and consequently it is possible to read out quantum information in the smallest devices, offering new avenues for the coherent manipulation down to single molecules.

In a recent work, Ogawa et al. (2024) proposed a model for celestial conformal field theory (CFT) based on the $H_{3}^{+}$-Wess-Zumino-Novikov-Witten (WZNW) model. In this paper, we extend the model advanced by Ogawa et al. (2024), demonstrating how it can holographically generate tree-level MHV scattering amplitudes for both gluons and gravitons when analytically continued to the ultra-hyperbolic Klein space $\mathbf{R}_{2}^{2}$, thereby offering an alternative to celestial Liouville theory. We construct a holographic dictionary in which vertex operators and conformal primaries in celestial CFT are derived from their worldsheet counterparts in Euclidean $AdS_{3}$ (bosonic) string theory. Within this dictionary, we derive the celestial stress-energy tensor, compute the two- and three-point functions, and determine the celestial operator product expansion (OPE). Additionally, we derive a system of partial differential equations that characterises the celestial amplitudes of our model, utilising the Knizhnik--Zamolodchikov (KZ) equations and worldsheet Ward identities. In the Appendix, we provide a concise introduction to the $H_{3}^{+}$-WZNW model, with emphasis on its connection to Euclidean $AdS_{3}$ string theory., Comment: 50 pp

In 2014, Vesti proposed the problem of determining the repetition threshold for infinite rich words, i.e., for infinite words in which all factors of length $n$ contain $n$ distinct nonempty palindromic factors. In 2020, Currie, Mol, and Rampersad proved a conjecture of Baranwal and Shallit that the repetition threshold for binary rich words is $2 + \sqrt{2}/2$. In this paper, we prove a structure theorem for $16/7$-power-free ternary rich words. Using the structure theorem, we deduce that the repetition threshold for ternary rich words is $1 + 1/(3 - \mu) \approx 2.25876324$, where $\mu$ is the unique real root of the polynomial $x^3 - 2x^2 - 1$., Comment: 60 pages

In this note, we continue our study of Liouville theory and celestial amplitudes by deriving a set of partial differential equations governing the $n$-point MHV celestial amplitudes for gluons and gravitons, parametrised by the Liouville coupling constant $b$. These equations provide a systematic framework for computing the perturbative expansion in $b$ of the celestial amplitudes, which are known to reproduce the tree-level MHV $n$-point functions for pure Yang-Mills and Einstein gravity in the semiclassical $b\rightarrow0$ limit. We demonstrate that the $\mathcal{O}(b^{2})$ corrections are logarithmic for both gluons and gravitons. Furthermore, we compute the correction to the celestial operator product expansion (OPE) parametrised by $b^{2}$. In the case of gluons, the resulting deformation of the celestial OPE is shown to be isomorphic to the one-loop correction of the celestial OPE in pure Yang-Mills theory. We then propose that "celestial Liouville theory," extended beyond the semiclassical limit, encodes the one-loop regime of pure Yang-Mills theory. A formally analogous computation is performed for Einstein gravity to ascertain the deformation of the celestial OPE induced by a non-zero Liouville coupling constant. However, as we shall explain, the physical interpretation of this result remains an open problem due to the intricate nature of the loop-corrected holomorphic collinear limit in graviton scattering amplitudes., Comment: 35 pp

We revisit the construction of the duality group for $\mathcal N=2$ $\widehat{A}_n$-shaped quivers SCFTs and generalize it to the previously unexplored case of $\widehat{D}_n$-shaped quivers. We then provide a systematic description of non-invertible duality symmetries in both classes. Furthermore, we characterize the $\mathcal N=1$ mass deformations of these theories that preserve such symmetries, thereby identifying a large class of $\mathcal N=1$ SCFTs with non-invertible duality symmetries inherited from their parent $\mathcal N=2$ theories., Comment: 44 pages, 16 figures

This paper concerns the avoidability of abelian and additive powers in infinite rich words. In particular, we construct an infinite additive $5$-power-free rich word over $\{0,1\}$ and an infinite additive $4$-power-free rich word over $\{0, 1, 2\}$. The alphabet sizes are as small as possible in both cases, even for abelian powers., Comment: 14 pages

In this note, we show that tree-level MHV $n$-graviton amplitudes, when analytically continued to Klein space, can be holographically generated as the correlators of a two-dimensional conformal field theory ($2d$ CFT) in the large-$N$ semiclassical $b\rightarrow0$ limit. This $2d$ CFT is composed of a Liouville field theory, coupled to a level-one $SO\left(N\right)$ Kac-Moody current, and a doublet of free fermions residing on $\mathbf{CP}^{1}$., Comment: 27 pages

In this paper we study germs of holomorphic foliations, at the origin of the complex plane, tangent to Pfaffian hypersurfaces - integral hypersurfaces of real analytic 1-forms - satisfying the Rolle-Khovanskii condition. This hypothesis leads us to conclude that such a foliation is defined by a closed meromorphic 1-form, also allowing the classification of the simple models in its reduction of singularities., Comment: 23 pages

We present the first detailed study of the effect of a strong magnetic field on single-electron pumping in a device utilising a finger-gate split-gate configuration. In the quantum Hall regime, we demonstrate electron pumping from Landau levels in the leads, where the measurements exhibit pronounced oscillations in the lengths of the pumping plateaus with the magnetic field, reminiscent of Shubnikov-de Haas oscillations. This similarity indicates that the pumping process is dependent on the density of states of the 2D electron gas over a narrow energy window. Based on these observations, we develop a new theoretical description of the operation of single-electron pumps which for the first time allows for the determination of the physical parameters of the experiment; such as the capture energy of the electrons, the broadening of the quantised Landau levels in the leads, and the quantum lifetime of the electrons., Comment: 8 pages, 4 figures

Laparoscopic video tracking primarily focuses on two target types: surgical instruments and anatomy. The former could be used for skill assessment, while the latter is necessary for the projection of virtual overlays. Where instrument and anatomy tracking have often been considered two separate problems, in this paper, we propose a method for joint tracking of all structures simultaneously. Based on a single 2D monocular video clip, we train a neural field to represent a continuous spatiotemporal scene, used to create 3D tracks of all surfaces visible in at least one frame. Due to the small size of instruments, they generally cover a small part of the image only, resulting in decreased tracking accuracy. Therefore, we propose enhanced class weighting to improve the instrument tracks. We evaluate tracking on video clips from laparoscopic cholecystectomies, where we find mean tracking accuracies of 92.4% for anatomical structures and 87.4% for instruments. Additionally, we assess the quality of depth maps obtained from the method's scene reconstructions. We show that these pseudo-depths have comparable quality to a state-of-the-art pre-trained depth estimator. On laparoscopic videos in the SCARED dataset, the method predicts depth with an MAE of 2.9 mm and a relative error of 9.2%. These results show the feasibility of using neural fields for monocular 3D reconstruction of laparoscopic scenes.

To build a large scale quantum circuit comprising millions of cryogenic qubits will require an efficient way to supply large numbers of classic control signals. Given the limited number of direct connections allowed from room temperature, multiple level of signal multiplexing becomes essential. The stacking of hardware to accomplish this task is highly dependent on the lowest level implementation of control electronics, of which an open question is the feasibility of mK integration. Such integration is preferred for signal transmission and wire interconnection, provided it is not limited by the large power dissipation involved. Novel cryogenic electronics that prioritises power efficiency has to be developed to meet the tight thermal budget. In this paper, we present a power efficient approach to implement charge-locking array.

In this paper, we present a reconfigurable multiplex (MUX) setup that increases the throughput of electrical characterisation at cryogenic temperature. The setup separates the MUX circuitry from quantum device under test (qDUT), allowing qDUT chips to be exchanged easily and MUX chips to be reused. To interface with different types of qDUTs, board-level designs are incorporated to allow interconnects flexibly routed into different topology. MUXs are built based on a multiple level selective gating (MLSG) scheme, where the number of multiplexed output channels (interconnects) is exponentially dependent on the number of control lines. In the prototype setup presented in this paper, with 14 out of 44 existing wires from room temperature, 4 MUXs at cryogenic temperature can supply in total 128 interconnects to interface with qDUTs. We validate the MUX setup operation and assess the various limits existed by measuring k$\Omega$ resistors made of $\mu$m-size graphene ribbons. We further demonstrate the setup by performing charge transport measurement on 128 nm-size graphene quantum devices in a single cooling down.

Intensive care unit (ICU) patients often develop new health-related problems in their long-term recovery. Health care professionals keeping a diary of a patient's stay is a proven strategy to tackle this but faces several adoption barriers, such as lack of time and difficulty in knowing what to write. Large language models (LLMs), with their ability to generate human-like text and adaptability, could solve these challenges. However, realizing this vision involves addressing several socio-technical and practical research challenges. This paper discusses these challenges and proposes future research directions to utilize the potential of LLMs in ICU diary writing, ultimately improving the long-term recovery outcomes for ICU patients., Comment: 3 pages, under review

Out of the more than 5,000 detected exoplanets a considerable number belongs to a category called 'mini-Neptunes'. Interior models of these planets suggest that they have some primordial, H-He dominated atmosphere. As this type of planet does not occur in the solar system, understanding their formation is a key challenge in planet formation theory. Unfortunately, quantifying the H-He, based on their observed mass and radius, is impossible due to the degeneracy of interior models. We explore the effects that different assumptions on planet formation have on the nebular gas accretion rate, particularly by exploring the way in which solid material interacts with the envelope. This allows us to estimate the range of possible post-formation primordial envelopes. Thereby we demonstrate the importance of envelope enrichment on the initial primordial envelope which can be used in evolution models. We apply formation models that include different solid accretion rate prescriptions. Our assumption is that mini-Neptunes form beyond the ice-line and migrate inward after formation, thus we form planets in-situ at 3 and 5 au. We consider that the envelope can be enriched by the accreted solids in the form of water. We study how different assumptions and parameters influence the ratio between the planet's total mass and the fraction of primordial gas. The primordial envelope fractions for small- and intermediate-mass planets (total mass below 15 M$_{\oplus}$) can range from 0.1% to 50%. Envelope enrichment can lead to higher primordial mass fractions. We find that the solid accretion rate timescale has the largest influence on the primordial envelope size. Primordial gas accretion rates can span many orders of magnitude. Planet formation models need to use a self-consistent gas accretion prescription., Comment: 23 pages, 16 figures, 5 tables. Accepted for publication in A&A

We extend the Abreu-Guillemin theory of invariant K\"ahler metrics from toric symplectic manifolds to any symplectic manifold admitting a toric action of a symplectic torus bundle. We show that these are precisely the symplectic manifolds admitting a Lagrangian fibration with elliptic singularities. The base of such a toric Lagrangian fibration is a codimension 0 submanifold with corners of an integral affine manifold, called a Delzant subspace. This concept generalizes the Delzant polytope associated with a compact symplectic toric manifold. Given a Delzant subspace of finite type, we provide a Delzant-type construction of a Lagrangian fibration with the moment image being the specified Delzant subspace. We establish a 1:1 correspondence between invariant K\"ahler metrics and a pair consisting of an elliptic connection on the total space of the fibration and a hybrid $b$-metric on the base Delzant subspace, both with specified residues over the facets. Finally, we characterize extremal invariant K\"ahler metrics as those whose scalar curvature descends to an affine function on the base integral affine manifold. We show that this provides a method for finding and constructing extremal K\"ahler metrics., Comment: 58 pages. Comments welcomed!

In this paper we study a natural generalization of symplectic toric manifolds in the context of regular Poisson manifolds of compact types. To be more precise, we consider a class of multiplicity-free Hamiltonian actions by regular proper symplectic groupoids that we call faithful. Given such a groupoid, we classify its faithful multiplicity-free Hamiltonian actions in terms of what we call Delzant subspaces of its orbit space -- certain `suborbifolds with corners' satisfying the Delzant condition relative to the integral affine orbifold structure of the orbit space. This encompasses both the classification of symplectic toric manifolds (due to Delzant) in terms of Delzant polytopes and the classification of proper Lagrangian fibrations over an integral affine base manifold (due to Duistermaat) in terms of a sheaf cohomology group. Each Delzant subspace comes with an orbifold version of this cohomology, the degree one part of which classifies faithful multiplicity-free Hamiltonian actions with momentum map image equal to the Delzant subspace, provided there exists such an action. The obstruction to existence is encoded by a degree two class in this cohomology: the Lagrangian Dixmier-Douady class. In addition to the above, we introduce another invariant, which leads to a variation of our classification result involving only classical sheaf cohomology and the group cohomology of certain modules for the isotropy groups of the groupoid.