@article{21408, abstract = {Rational design strategies for self-assembly require a detailed understanding of both the equilibrium state and the assembly kinetics. While the former is starting to be well understood, the latter remains a major theoretical challenge, especially in programmable systems and the so-called semi-addressable regime, where binding is often nondeterministic and the formation of off-target structures negatively influences the assembly. Here, we show that it is possible to simultaneously sculpt the assembly outcome and the assembly kinetics through the underexplored design space of binding energies and particle concentrations. By formulating the assembly process as a complex reaction network, we calculate and optimize the tradeoff between assembly speed and quality and show that parameter optimization can speed up assembly by many orders of magnitude without lowering the yield of the target structure. Although the exact speedup varies from design to design, we find the largest speedups for nondeterministic systems where unoptimized assembly is the slowest, sometimes even making them assemble faster than optimized, fully addressable designs. Therefore, these results not only solve a key challenge in semi-addressable self-assembly but further emphasize the utility of semi-addressability, where designs have the potential to be faster as well as cheaper (fewer particle species) and better (higher yield). More broadly, our results highlight the importance of parameter optimization in programmable self-assembly and provide practical tools for simultaneous optimization of kinetics and yield in a wide range of systems.}, author = {Hübl, Maximilian and Goodrich, Carl Peter}, issn = {1089-7690}, journal = {Journal of Chemical Physics}, number = {8}, publisher = {AIP Publishing}, title = {{Simultaneous optimization of assembly time and yield in programmable self-assembly}}, doi = {10.1063/5.0304731}, volume = {164}, year = {2026}, } @article{21449, abstract = {Three-dimensional (3D) crystals offer a route to scaling up trapped-ion systems for quantum sensing and quantum simulation applications; however, engineering coherent spin-motion couplings and effective spin-spin interactions in large crystals poses technical challenges associated with decoherence and prolonged timescales to generate appreciable entanglement. Here, we explore the possibility of speeding up these interactions in 3D crystals via parametric amplification. For this purpose, we derive a general Hamiltonian for the parametric amplification of spin-motion coupling that is broadly applicable to normal modes with motion transverse to or along the spatial extent of the crystal. Unlike in lower-dimensional crystals, we find that the ability to faithfully (uniformly) amplify the spin-spin interactions in 3D crystals depends on the physical implementation of the spin-motion coupling. We consider the light-shift gate, and the so-called phase-insensitive and phase-sensitive Mølmer-Sørensen (MS) gates, and we find that only the phase-sensitive MS gate can be faithfully amplified in general 3D crystals. We discuss a situation where nonuniform amplification can be advantageous. We also reconsider the effect of counter-rotating terms on parametric amplification and find that they are not as detrimental as previous studies suggest.}, author = {Hawaldar, Samarth and Nikhil, N. and Rey, Ana Maria and Bollinger, John J. and Shankar, Athreya}, issn = {2331-7019}, journal = {Physical Review Applied}, number = {3}, publisher = {American Physical Society}, title = {{Parametric amplification of spin-motion coupling in three-dimensional trapped-ion crystals}}, doi = {10.1103/h1m9-h3yw}, volume = {25}, year = {2026}, } @article{21452, abstract = {Galaxies exhibit a tight correlation between their star formation rate (SFR) and stellar mass over a wide redshift range known as the star-forming main sequence (SFMS). With JWST, the SFMS can now be investigated at high redshifts down to masses of ∼106 M⊙, using sensitive star formation rate tracers such as the Hα emission, which allow us to probe the variability in the star formation histories. We present inferences of the SFMS based on 316 Hα-selected galaxies at z ∼ 4 − 5 with log(M★/M⊙) = 6.4 − 10.6. These galaxies were identified behind the Abell 2744 lensing cluster with NIRCam grism spectroscopy from the survey All the Little Things (ALT). At face value, our data suggest a shallow slope in the SFMS (SFR ∝ M★α, with α = 0.45). After we corrected this for the Hα-flux limited nature of our survey using a Bayesian framework, the slope steepened to α = 0.59+0.10−0.09, whereas current data on their own are inconclusive on the mass dependence of the scatter. These slopes differ significantly from the slope of ∼1 that is expected from the observed evolution of the galaxy stellar mass function and from simulations. When we fixed the slope to α = 1, we found evidence for a decreasing intrinsic scatter with stellar mass (from ∼0.5 dex at M★ = 108 M⊙ to 0.4 dex at M★ = 1010 M⊙). This difference might be explained by a (combination of) luminosity-dependent SFR(Hα) calibration, a population of (mini)-quenched low-mass galaxies, or underestimated dust attenuation in high-mass galaxies. Future deep observations with different facilities can quantify these processes, which will enable us to achieve better insights into the variability of the star formation histories.}, author = {Di Cesare, Claudia and Matthee, Jorryt J and Naidu, Rohan P. and Torralba, Alberto and Kotiwale, Gauri and Kramarenko, Ivan and Blaizot, Jeremy and Rosdahl, Joakim and Leja, Joel and Iani, Edoardo and Adamo, Angela and Covelo-Paz, Alba and Furtak, Lukas J. and Heintz, Kasper E. and Mascia, Sara and Navarrete, Benjamín and Oesch, Pascal A. and Romano, Michael and Shivaei, Irene and Tacchella, Sandro}, issn = {1432-0746}, journal = {Astronomy & Astrophysics}, publisher = {EDP Sciences}, title = {{The slope and scatter of the star-forming main sequence at z ∼ 5: Reconciling observations with simulations}}, doi = {10.1051/0004-6361/202557790}, volume = {707}, year = {2026}, } @article{21469, abstract = {Terahertz (THz) spectroscopy is a powerful probe of low-energy excitations in complex materials. Extending it into the nonlinear regime broadens its scope and can provide valuable insight into interactions among these modes. However, interpreting nonlinear spectra is challenging because resonant features in this case do not always reflect intrinsic material dynamics. Here, we study nonlinear THz-induced Kerr effect in a generic material LaAlO3. After detailed analysis of temporal oscillations of the Kerr signal, we identify an 𝐸𝑔 Raman mode at 1.1 THz excited through a two-photon process, while two additional peaks (0.86 and 0.36 THz) arise from phase matching of the near-infrared probe beam with co- and counterpropagating THz pump fields, mediated by off-resonant electronic hyperpolarizability. These results demonstrate the crucial role of kinematic effects in shaping THz-induced Kerr response and establish a framework for interpreting nonlinear spectroscopies in complex materials.}, author = {Shen, Chao and Frenzel, Maximilian and Maehrlein, Sebastian F. and Alpichshev, Zhanybek}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {10}, publisher = {American Physical Society}, title = {{Disentangling electronic and ionic nonlinear polarization effects in bulk THz Kerr response}}, doi = {10.1103/1c5k-9z82}, volume = {136}, year = {2026}, } @article{21471, author = {Backlund, Sofia Maria and Stankowski, Sean and Soler Schaller, Rosina Matilde}, issn = {1537-2197}, journal = {American Journal of Botany}, number = {3}, publisher = {Wiley}, title = {{Seeds as space-time travelers: How does evolution balance the joint benefits and trade-offs of dormancy and dispersal?}}, doi = {10.1002/ajb2.70175}, volume = {113}, year = {2026}, } @article{21482, abstract = {Controlling the size and shape of assembled structures is a fundamental challenge in self-assembly and is highly relevant in material design and biology. Here, we show that specific but promiscuous short-range binding interactions make it possible to economically assemble linear filaments of user-defined length. Our approach leads to independent control over the mean and width of the filament size distribution and allows us to smoothly explore design trade-offs between assembly quality (spread in size) and cost (number of particle species). We employ a simple hierarchical assembly protocol to minimize assembly times and show that multiple stages of hierarchy make it possible to extend our approach to the assembly of higher-dimensional structures. Our work provides a conceptually simple solution to size control that is applicable to a broad range of systems, from DNA nanoparticles to supramolecular polymers and beyond.}, author = {Hübl, Maximilian and Goodrich, Carl Peter}, issn = {2643-1564}, journal = {Physical Review Research}, publisher = {American Physical Society}, title = {{Entropic size control of self-assembled filaments}}, doi = {10.1103/68rs-3qgn}, volume = {8}, year = {2026}, } @article{21485, abstract = {Insulating oxides are among the most abundant solid materials in the universe1,2,3. Of the many ways in which they influence natural phenomena, perhaps the most consequential is their capacity to transfer electrical charge during contact4,5,6,7,8,9,10—which occurs even between samples of the same oxide—yet the symmetry-breaking parameter that causes this remains unidentified11,12. Here we show that adventitious carbonaceous molecules adsorbed from the environment are the symmetry-breaking factor in same-material oxide contact electrification (CE). We use acoustic levitation to measure charge exchange between a sphere and a plate composed of identical amorphous silicon dioxide (SiO2). Although charging polarity is random for co-prepared samples, we control it with baking or plasma treatment. Observing the charge-exchange relaxation afterwards, we see dynamics over a timescale of hours and connect this directly to the presence of adventitious carbon with time-of-flight mass spectrometry, low-energy ion scattering and infrared spectroscopy. Going further, we confirm that adventitious carbon can even determine charge exchange among different oxides. Our results identify the symmetry-breaking parameter that causes insulating oxides to exchange charge in settings ranging from desert sands4 to volcanic plumes5,6, while simultaneously highlighting an overlooked factor in CE more broadly.}, author = {Grosjean, Galien M and Ostermann, Markus and Sauer, Markus and Hahn, Michael and Pichler, Christian M. and Fahrnberger, Florian and Pertl, Felix and Balazs, Daniel and Link, Mason M. and Kim, Seong H. and Schrader, Devin L. and Blanco, Adriana and Gracia, Francisco and Mujica, Nicolás and Waitukaitis, Scott R}, issn = {1476-4687}, journal = {Nature}, number = {8106}, pages = {626--631}, publisher = {Springer Nature}, title = {{Adventitious carbon breaks symmetry in oxide contact electrification}}, doi = {10.1038/s41586-025-10088-w}, volume = {651}, year = {2026}, } @phdthesis{21651, abstract = {Blockchains enable distributed consensus in permissionless settings, where participants are unknown, dynamically changing, and do not trust each other. While Bitcoin, based on Proof-of-Work (PoW), was the first protocol in this model, significant research has focused on permissionless protocols using alternative physical resources, specifically Proof-of-Space (PoSpace) and Verifiable Delay Functions (VDFs). This thesis investigates the theoretical limits and design space of longest-chain protocols in the fully permissionless and dynamically available settings using these three resources. First, we address the feasibility of blockchains relying solely on storage as a resource. We prove a fundamental impossibility result: there exists no secure longest-chain protocol based exclusively on Proof-of-Space in the fully permissionless or dynamically available settings. Further, we quantify the adversarial capabilities required to execute a double-spend attack. Our result formally justifies the necessity of coupling PoSpace with time-dependent primitives (such as VDFs) or to move to less permissive settings (quasi-permissionless or permissioned) to ensure security. Second, we generalize Nakamoto-like heaviest chain consensus to protocols utilizing combinations of multiple physical resources. We analyze chain selection rules governed by a weight function Γ(S, V,W), which assigns weight to blocks based on recorded Space (S), VDF speed (V ), and Work (W). We provide a complete classification of secure weight functions, proving that a weight function is secure against private double-spend attacks if and only if it is homogeneous in the timed resources (V,W) and sub-homogeneous in S. This framework unifies existing protocols like Bitcoin and Chia under a single theoretical model and provides a powerful tool for designing new longest-chain blockchains from a mix of physical resources.}, author = {Baig, Mirza Ahad}, isbn = {978-3-99078-078-7}, issn = {2663-337X}, publisher = {Institute of Science and Technology Austria}, title = {{On secure chain selection rules from physical resources in a permissionless setting}}, doi = {10.15479/AT-ISTA-21651}, year = {2026}, } @article{21707, abstract = {Structural and functional differences between brain hemispheres are a common feature of animal nervous systems with reduced bilateral asymmetry often linked to impaired cognitive performance. How neuronal left-right asymmetry is initiated and integrated into a bilaterally symmetrical ground pattern is poorly understood. Here, we show that the directional asymmetry of a Drosophila central brain circuit originates from axonal interactions of two types of bilateral pioneer neurons. Subsequent recruitment of neighboring neurons into the asymmetric neuropil primordium results in hemisphere-specific microcircuits. Circuit lateralization requires dynamic expression of the cell adhesion molecule Fasciclin 2 to maintain structural plasticity in axonal remodeling. Reduced circuit asymmetry following cell type–specific Fasciclin 2 manipulation affects adult brain function. These results reveal an unexpected degree of developmental plasticity of late-born Drosophila neurons in the formation of a circuit node via the lateralized recruitment of symmetric circuit components.}, author = {Markovitsch, Johann W. and Mitić, Daniel and Del Pilar Jiménez García, Alisa and Zane, Alsberga and Kainz, Sarah and Kaur, Rashmit and Hummel, Thomas}, issn = {2375-2548}, journal = {Science Advances}, number = {13}, publisher = {American Association for the Advancement of Science}, title = {{Sequential formation of Drosophila circuit asymmetry via prolonged structural plasticity}}, doi = {10.1126/sciadv.aea6020}, volume = {12}, year = {2026}, } @unpublished{21737, abstract = {In calculus, l'Hopital's rule provides a simple way to evaluate the limits of quotient functions when both the numerator and denominator vanish. But what happens when we move beyond real functions on a real interval? In this article, we study when the quotient of two complex-valued functions in higher dimension can be defined continuously at the points where both functions vanish. Surprisingly, the answer is far subtler than in the real-valued setting. We provide a complete characterization for the continuity of the quotient function. We also point out why extending this result to smoother quotients remains an intriguing challenge.}, author = {Chern, Albert and Ishida, Sadashige}, booktitle = {arXiv}, keywords = {l’Hopital theorem, complex functions}, title = {{L'Hopital rules for complex-valued functions in higher dimensions}}, doi = {10.48550/ARXIV.2602.09958}, year = {2026}, } @article{21743, abstract = {We present symplectic structures on the shape space of unparameterized space curves that generalize the classical Marsden–Weinstein structure. Our method integrates the Liouville 1-form of the Marsden–Weinstein structure with Riemannian structures that have been introduced in mathematical shape analysis. We also derive Hamiltonian vector fields for several classical Hamiltonian functions with respect to these new symplectic structures.}, author = {Bauer, Martin and Ishida, Sadashige and Michor, Peter W.}, issn = {1432-1467}, journal = {Journal of Nonlinear Science}, number = {2}, publisher = {Springer Nature}, title = {{Symplectic structures on the space of space curves}}, doi = {10.1007/s00332-026-10266-8}, volume = {36}, year = {2026}, } @article{21763, abstract = {Reactive oxygen species (ROS) have been implicated in multiple signaling processes in plants, but the underlying mechanisms and roles remain enigmatic. In this study, we developed a method of live imaging of apoplastic ROS at the root surface. Distinct signals, including auxin, extracellular adenosine triphosphate, and rapid alkalinization factor 1 peptide, induce cytosolic calcium transients and apoplastic ROS bursts. Genetic and optogenetic manipulations of Arabidopsis identified calcium transients as necessary and sufficient for ROS bursts through activation of reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidases RBOHC and RBOHF. Apoplastic ROS bursts are not required, but they do limit gravity-induced root bending. Root bending is sensed by the stretch-activated calcium channel MCA1, leading to NADPH oxidase activation. The resulting ROS production stiffens cell walls to facilitate soil penetration. Apoplastic ROS thus provides a means to balance tissue flexibility and stiffness to navigate soil.}, author = {Kulich, Ivan and Vladimirtsev, Dmitrii and Randuch, Marek and Gao, Shiqiang and Citterico, Matteo and Konrad, Kai R. and Nagel, Georg and Wrzaczek, Michael and Cascaro, Léa and Vinet, Pauline and Durand, Pauline and Asnacios, Atef and Verma, Lokesh and Bennett, Malcolm J. and Pandey, Bipin K. and Friml, Jiří}, issn = {1095-9203}, journal = {Science}, number = {6795}, pages = {296--300}, publisher = {AAAS}, title = {{Calcium-triggered apoplastic ROS bursts balance gravity and mechanical signals for soil navigation}}, doi = {10.1126/science.adu8197}, volume = {392}, year = {2026}, } @article{21764, abstract = {Colloidal fluids can exhibit complex phase behavior and determining phase diagrams via experiments or computer simulations can be laborious. We demonstrate that the dispersion relation ω(k), obtained from dynamical density functional theory for the uniform density system, is a highly versatile tool for predicting where in the phase diagram complex crystals form. The sign of ω(k) determines whether density modes with wave number k grow or decay over time. We demonstrate the predictive power by investigating the complex phase behavior of particles interacting via core-shoulder pair potentials. With complementary Monte Carlo simulations, we show that regions of the phase diagram where ωðkÞ has one or several unstable (growing) wave numbers are also where crystalline phases occur. Going further, by tuning these unstable wave numbers via the interaction-potential and state-point parameters, we design systems with quasicrystals in the phase diagram. We identify a system with a certain shoulder range exhibiting at least ten different phases. Our general approach accelerates considerably the mapping of complex phase diagrams, crucial for the design of new materials.}, author = {Wassermair, Michael and Kahl, Gerhard and Roth, Roland and Archer, Andrew J.}, issn = {1079-7114}, journal = {Physical Review Letters}, number = {14}, publisher = {American Physical Society}, title = {{Navigating complex phase diagrams in soft matter systems}}, doi = {10.1103/nbvt-fgjy}, volume = {136}, year = {2026}, } @article{21776, abstract = {Pyridyl motifs equipped with N-substituents can be powerful ligands for catalysis, yet their broader adoption is limited by the lack of a practical method to prepare these scaffolds. We report a modular, robust, and versatile Buchwald–Hartwig amination protocol that enables the rapid synthesis of bipyridine, phenanthroline, terpyridine, and pybox ligands bearing dialkylamine, diarylamine, and heteroaromatic N-substituents. These conditions streamline ligand library synthesis and will facilitate systematic studies in catalysis and related applications.}, author = {Petrik, Adam and Bena, Aleksander and Baunis, Haralds and Kelch, Riley M. and Yoon, Tehshik P. and Pieber, Bartholomäus}, issn = {1615-4169}, journal = {Advanced Synthesis & Catalysis}, number = {9}, publisher = {Wiley}, title = {{Facile access to N-substituted pyridyl ligands}}, doi = {10.1002/adsc.70417}, volume = {368}, year = {2026}, } @article{21845, abstract = {UTe2 exhibits the remarkable phenomenon of re-entrant superconductivity, whereby the zero-resistance state reappears above 40 tesla after being suppressed with a field of around 10 tesla. One potential pairing mechanism, invoked in the related re-entrant superconductors UCoGe and URhGe, involves transverse fluctuations of a ferromagnetic order parameter. However, the requisite ferromagnetic order—present in both UCoGe and URhGe—is absent in UTe2, and neutron scattering shows instead that the magnetic susceptibility is peaked at an antiferromagnetic wavevector. Here, we measure the magnetotropic susceptibility of UTe2 across two field-angle planes. This quantity is sensitive to the magnetic susceptibility in a direction transverse to the applied magnetic field—a quantity that is not accessed in conventional magnetization measurements. We observe a very large decrease in the magnetotropic susceptibility over a broad range of field orientations, indicating a large increase in the transverse magnetic susceptibility. Because our technique probes the magnetic susceptibility in the long wavelength (q = 0) limit, this suggests that the strong transverse susceptibility arises from ferromagnetic spin fluctuations. These ferromagnetic fluctuations are likely important for understanding the pairing mechanism in UTe2, as all three superconducting phases of UTe2 surround this region of enhanced susceptibility in the field-angle phase diagram.}, author = {Zambra, Valeska and Nathwani, Amit and Nauman, Muhammad and Lewin, Sylvia K. and Frank, Corey E. and Butch, Nicholas P. and Shekhter, Arkady and Ramshaw, B. J. and Modic, Kimberly A}, issn = {2041-1723}, journal = {Nature Communications}, publisher = {Springer Nature}, title = {{Giant transverse magnetic fluctuations at the edge of re-entrant superconductivity in UTe2}}, doi = {10.1038/s41467-026-71899-7}, volume = {17}, year = {2026}, } @article{21917, abstract = {A defining feature of quantum many-body systems is the exponential scaling of the Hilbert space with the number of degrees of freedom. This exponential complexity naïvely renders a complete state characterization, for instance via the complete set of bipartite Renyi entropies for all disjoint regions, a challenging task. Recently, a compact way of storing subregions' purities by encoding them as amplitudes of a fictitious quantum wave function, known as entanglement feature, was proposed. Notably, the entanglement feature can be a simple object even for highly entangled quantum states. However the complexity and practical usage of the entanglement feature for general quantum states has not been explored. In this work, we demonstrate that the entanglement feature can be efficiently learned using only a polynomial amount of samples in the number of degrees of freedom through the so-called tensor cross interpolation (TCI) algorithm, assuming it is expressible as a finite bond dimension MPS. We benchmark this learning process on Haar and random MPS states, confirming analytic expectations. Applying the TCI algorithm to quantum eigenstates of various one dimensional quantum systems, we identify cases where eigenstates have entanglement feature learnable with TCI. We conclude with possible applications of the learned entanglement feature, such as quantifying the distance between different entanglement patterns and finding the optimal one-dimensional ordering of physical indices in a given state, highlighting the potential utility of the proposed purity interpolation method.}, author = {Kolisnyk, Dmytro and Medina Ramos, Raimel A and Vasseur, Romain and Serbyn, Maksym}, issn = {2521-327X}, journal = {Quantum}, publisher = {Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften}, title = {{Tensor cross interpolation of purities in quantum many-body systems}}, doi = {10.22331/q-2026-05-22-2114}, volume = {10}, year = {2026}, } @phdthesis{21918, author = {Khudiakova, Kseniia}, issn = {2663-337X}, pages = {89}, publisher = {Institute of Science and Technology Austria}, title = {{How epistasis and purifying selection shape genetic diversity}}, doi = {10.15479/AT-ISTA-21918}, year = {2026}, } @article{21929, abstract = {The import of proteins into mitochondria poses fundamental mechanistic challenges: aggregation-prone precursor proteins must be maintained in aqueous compartments and threaded through narrow pores without becoming stuck or mislocalized. Recent evidence from mitochondrial protein import studies and other chaperone systems underscores the critical role of dynamics in balancing sufficiently tight binding, promiscuity, specificity, and release. Dynamic binding of client precursor proteins to import machinery components arises naturally from the avidity of their interactions. Conformational entropy enhances their stability, while the multivalent nature of these interactions ensures that client transfer to downstream insertases occurs without a substantial energy barrier. Here, we discuss this emerging paradigm of dynamic protein handling, using examples where dynamic structures have been resolved and highlight outstanding questions.}, author = {Schneider, Jakob and Guillerm, Undina and Simoes Pereira, Caroline and Schanda, Paul}, issn = {1469-896X}, journal = {Protein Science}, number = {6}, publisher = {Wiley}, title = {{Dynamic disorder is crucial for mitochondrial protein import}}, doi = {10.1002/pro.70630}, volume = {35}, year = {2026}, } @unpublished{21963, abstract = {The cerebral cortex consists of immense numbers of neuronal and glial cell-types derived from radial glial progenitor (RGP) cells. How RGPs generate appropriate quantities of distinct cortical cell-types to safeguard a brain of correct size, is not well understood. However, genetic aberration in human, including mutations in PTEN, lead to cortical malformation such as macrocephaly, albeit with unknown etiology. Here we utilized Mosaic Analysis with Double Markers (MADM)-based clonal analysis and single cell phenotyping to decipher the role of Pten in neurogenic and gliogenic RGP lineage progression during cortical ontogeny. While neurogenic RGP lineage progression and projection neuron production was moderately altered in the absence of Pten, cortical astrocyte production was drastically increased. Through genetic epistasis experiments we show that the loss of Pten uncouples astrocyte generation from essential growth factor signaling hubs, funneling into MAPK. Collectively, our results suggest that Pten regulates RGP lineage progression with distinct sequential functions in cortical projection neurogenesis and astrocyte production to ensure the emergence of a correctly-sized cerebral cortex.}, author = {Miranda, Osvaldo and Contreras, Ximena and Pauler, Florian and Davaatseren, Amarbayasgalan and Amberg, Nicole and Streicher, Carmen and Villalba Requena, Ana and Heger, Anna-Magdalena and Marie, Corentine and Hassan, Bassem A. and Rülicke, Thomas and Hippenmeyer, Simon}, booktitle = {bioRxiv}, title = {{Pten orchestrates neurogenic radial glia lineage progression and tunes neocortical astrocyte production}}, doi = {10.64898/2026.05.01.722191}, year = {2026}, } @article{21981, abstract = {For Hamiltonian actions of semidirect products G = FxH, we study 2-cocycles arising from residual Hamiltonian actions of F on Hamiltonian reductions for H. The motivation comes from the study of Teichmüller spaces for surfaces with boundary, which carry Hamiltonian actions of the Virasoro algebra. In this paper, we give a general setup for the problem, and we suggest an easier way to obtain the Gelfand-Fuchs 2-cocycles for Hamiltonian actions on Teichmüller spaces.}, author = {Goncharov, Viacheslav}, issn = {1879-1662}, journal = {Journal of Geometry and Physics}, publisher = {Elsevier}, title = {{An easier way to compute 2-cocycles coming from a reduction for semidirect products}}, doi = {10.1016/j.geomphys.2026.105878}, volume = {227}, year = {2026}, }