@article{65777, abstract = {{Abstract In this work, we address the numerical identification of entanglement in dynamical scenarios. To this end, we consider different programs based on the restriction of the evolution to the set of separable (i.e., non-entangled) states, together with the discretization of the space of variables for numerical computations. As a first approach, we apply linear splitting methods to the restricted, continuous equations of motion derived from variational principles. We utilize an exchange interaction Hamiltonian to confirm that the numerical and analytical solutions coincide in the limit of small time steps. The application to different Hamiltonians shows the wide applicability of the method to detect dynamical entanglement. To avoid the derivation of analytical solutions for complex dynamics, we consider variational, numerical integration schemes, introducing a variational discretization for Lagrangians linear in velocities. Here, we examine and compare two approaches: one in which the system is discretized before the restriction is applied, and another in which the restriction precedes the discretization. We find that the ‘first-discretize-then-restrict’ method becomes numerically unstable, already for the example of an exchange-interaction Hamiltonian, which can be an important consideration for the numerical analysis of constrained quantum dynamics. Thereby, broadly applicable numerical tools, including their limitations, for studying entanglement over time are established for assessing the entangling power of processes that are used in quantum information theory.}}, author = {{Offen, Christian and Wembe Moafo, Boris Edgar and Ares, Laura and Sperling, Jan and Ober-Blöbaum, Sina}}, issn = {{1751-8113}}, journal = {{Journal of Physics A: Mathematical and Theoretical}}, number = {{22}}, publisher = {{IOP Publishing}}, title = {{{Numerical approaches to entangling dynamics from variational principles}}}, doi = {{10.1088/1751-8121/ae6d51}}, volume = {{59}}, year = {{2026}}, } @article{65476, abstract = {{Service research has evolved into an interdisciplinary research field that bridges diverse disciplines, including information systems (IS) and marketing. Nearly two decades ago, the service system concept was introduced as a foundational abstraction in service research, drawing on ideas from the service-dominant logic (S-D logic) of marketing. Despite its widespread adoption in service research, particularly in the IS discipline, the service system concept lacks a solid theoretical foundation. This has resulted in conceptual ambiguity and overlap with related constructs, such as service ecosystems. Moreover, it has largely remained a static analytical lens, insufficiently capturing dynamic service phenomena, including value co-creation and co-destruction, as well as the emergence of institutional arrangements. To address these limitations, we propose Luhmann’s systems theory (LST) as a robust framework for conceptualizing service systems as autopoietic (self-creating) systems, in which communication serves as the fundamental mechanism that drives value co-creation. We derive five theoretical propositions from this re-conceptualization that clarify conceptual ambiguity and allow researchers to explore dynamic service phenomena in greater depth. Given LST’s general approach, our conceptualization provides a theoretically grounded, interdisciplinary foundation for advancing service research.}}, author = {{Beverungen, Daniel and Poeppelbuss, Jens and Hemmrich, Simon and Iqbal, Taskeen}}, issn = {{1019-6781}}, journal = {{Electronic Markets}}, keywords = {{Service system, Service ecosystem, Systems theory, Service research}}, number = {{1}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Service through communication—Conceptualizing service systems with Luhmann’s systems theory}}}, doi = {{10.1007/s12525-026-00889-w}}, volume = {{36}}, year = {{2026}}, } @inproceedings{65901, author = {{Steffens, Hanna and Yigitbas, Enes and Sauer, Stefan}}, booktitle = {{Proceedings of the 28th International Conference on Human-Computer Interaction (HCII 2026)}}, publisher = {{Springer}}, title = {{{Effects of Vertical Price Placement on Consumer Behaviour: A VR-Based Investigation Including Eye Tracking}}}, year = {{2026}}, } @inproceedings{65903, author = {{Seidan, Salah and Yigitbas, Enes and Leichtweiß, Justus}}, booktitle = {{Proceedings of the 10th International Conference on Intelligent Computing and Virtual & Augmented Reality Simulations (ICVARS 2026)}}, publisher = {{IEEE}}, title = {{{Change Your Perspective - A VR Driving Simulator to Enhance Safety Awareness in Public Road Traffic}}}, year = {{2026}}, } @inproceedings{65904, author = {{Krings, Sarah Claudia and Yigitbas, Enes and Sauer, Stefan}}, booktitle = {{Proceedings of the 18th ACM SIGCHI Symposium on Engineering Interactive Computing Systems (EICS 2026)}}, publisher = {{ACM}}, title = {{{A Framework Supporting Context-Awareness for Transitional Cross-Reality Applications}}}, year = {{2026}}, } @article{65905, author = {{Yigitbas, Enes and Dell'Aquila, Alessio}}, journal = {{Proceedings of the ACM on Human-Computer Interaction - EICS }}, publisher = {{ACM}}, title = {{{Exploring the Dynamics of Authoring Interactive VR Environments: Human Collaboration vs. AI Assistance}}}, year = {{2026}}, } @inbook{66437, author = {{Krings, Sarah Claudia}}, booktitle = {{Lecture Notes in Computer Science}}, isbn = {{9783032260505}}, issn = {{0302-9743}}, publisher = {{Springer Nature Switzerland}}, title = {{{Cross-Reality Context Awareness}}}, doi = {{10.1007/978-3-032-26051-2_4}}, year = {{2026}}, } @inproceedings{66687, abstract = {{With a range of consumer devices available, augmented reality (AR) continues to make its way into everyday life and is also increasingly used in professional and sensitive contexts. Especially collaborative use cases, such as remote meetings or maintenance, offer potential, but also move issues in the area of privacy and security into focus. We conducted a scoping review to gain an overview of the current situation and found a lack of clear standards, with most approaches focusing on single protection features. Using the knowledge from the scoping review, we set up and conducted expert interviews. They revealed that end-users are almost completely dependent on developers or device manufacturers regarding their options for protection. The interviews also showed that most developers put little focus on privacy and security, often due to external constraints, such as employers treating the topic as an “afterthought” and not budgeting enough time for it. The experts suggested offering better software support to developers to enable the inclusion of privacy and security with less overhead as a solution. It was also suggested that a general rise in privacy and security awareness could improve the overall situation.}}, author = {{Krings, Sarah Claudia and Yigitbas, Enes and Sauer, Stefan}}, booktitle = {{Blending Experiences in Interaction Design}}, editor = {{Maciel, Cristiano and Spano, Davide Lucio and Ardito, Carmelo and Freire, André and Prates, Raquel}}, isbn = {{978-3-032-22934-2}}, pages = {{253–276}}, publisher = {{Springer Nature Switzerland}}, title = {{{Perspectives on Privacy and Security in Collaborative AR - Insights from a Scoping Review and an Expert Interview Study}}}, year = {{2026}}, } @article{66688, author = {{Wüppelmann, Dennis and Yigitbas, Enes}}, issn = {{2944-7682}}, journal = {{GI - Software Engineering }}, publisher = {{Gesellschaft für Informatik, Bonn}}, title = {{{SecCityVR: Visualization and Collaborative Exploration of Software Vulnerabilities in Virtual Reality}}}, doi = {{10.18420/se2026_53}}, year = {{2026}}, } @article{66854, abstract = {{Abstract Investigating the real-time interplay between language and vision has traditionally involved a trade-off between experimental control and interactive setups. To address this challenge, we present a methodological framework that embeds the visual world paradigm (VWP) within a continuous, goal-directed human–robot interaction (HRI) task. By augmenting VWP in an HRI setup to produce standardized yet responsive verbal and non-verbal behaviours, the framework makes it possible to selectively examine comprehension, production, actions and their relation to visual attention in real-time. We demonstrate the utility of the framework through a proof-of-concept manipulating action structure, specifically path and manner, as well as other-initiated repair formats, namely open and restricted requests. The findings show that the setup reliably captures time-locked referential gaze dynamics following comprehension and preceding production processes. They further indicate that differences in action history systematically influence speakers’ pre-verbal cognitive processes and their subsequent linguistic choices. These findings suggest that HRI can provide a useful methodological middle ground to investigate language processes online in a tightly controlled setup without disrupting the interaction. More broadly, the framework offers a test bed for examining whether established psycholinguistic findings extend to HRI setups. At the same time, it provides HRI researchers with an empirical basis for developing adaptive agents informed by online language-vision interaction theories.}}, author = {{Singh, Amit and Rohlfing, Katharina J.}}, issn = {{0090-6905}}, journal = {{Journal of Psycholinguistic Research}}, number = {{5}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{A Methodological Framework for Studying Online Language–Vision Interplay in Human–Robot Interaction}}}, doi = {{10.1007/s10936-026-10296-z}}, volume = {{55}}, year = {{2026}}, } @inbook{66856, abstract = {{Abstract Goals are central to human actions: In fact, human actions are organized toward goals. Already early in human development, human perception becomes biased to goal-directed actions. A characteristic of social interaction is that goals can be shared among involved agents. This is a great benefit for designing sXAI as it allows explanation goals to be collaboratively negotiated. Even more, depending on the goal, users could be dynamically but minimalistically supported in their autonomous actions. Future sXAI developments can benefit from this chapter by recognizing how essential goals are and that they constitute an intersection of individual actions and social ecologies.}}, author = {{Rohlfing, Katharina J. and Singh, Amit and Groß, André and Wrede, Britta}}, booktitle = {{Social Explainable AI}}, isbn = {{9789819652891}}, publisher = {{Springer Nature Singapore}}, title = {{{Explanation Goals}}}, doi = {{10.1007/978-981-96-5290-7_6}}, year = {{2026}}, } @article{66855, author = {{Wildt, Eugenia and Singh, Amit and Rohlfing, Katharina J.}}, issn = {{0001-6918}}, journal = {{Acta Psychologica}}, publisher = {{Elsevier BV}}, title = {{{Infants' individual sensitivity to saliency shapes early word learning in social interaction}}}, doi = {{10.1016/j.actpsy.2026.106977}}, volume = {{266}}, year = {{2026}}, } @inproceedings{61444, abstract = {{Backchannels and fillers are important linguistic expressions in dialogue, but often treated as "noise" to be bypassed in modern transformer-based language models. Our work studies the representation of them in language models using three fine-tuning strategies. The models are trained on three dialogue corpora in English and Japanese, where backchannels and fillers are preserved and annotated, to investigate how fine-tuning can help LMs learn their representations. We first apply clustering analysis to the learnt representation of backchannels and fillers, and have found increased silhouette scores in representations from fine-tuned models, which suggests that fine-tuning enables LMs to distinguish the nuanced semantic variation in different backchannel and filler use. We also use natural language generation (NLG) metrics and qualitative analysis to confirm that the utterances generated by fine-tuned language models resemble human-produced utterances more closely. Our findings suggest the potentials of transforming general LMs into conversational LMs that are more capable of producing human-like languages adequately.}}, author = {{Wang, Yu and Lao, Leyi and Huang, Langchu and Skantze, Gabriel and Xu, Yang and Buschmeier, Hendrik}}, booktitle = {{Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics}}, location = {{San Diego, CA, USA}}, pages = {{5319--5348}}, publisher = {{Association for Computational Linguistics}}, title = {{{Investigating the representation of backchannels and fillers in fine-tuned language models}}}, doi = {{10.18653/v1/2026.acl-long.241}}, year = {{2026}}, } @inproceedings{65363, abstract = {{Recent theoretical advancement of information density in natural language has brought the following question on desk: To what degree does natural language exhibit periodicity pattern in its encoded information? We address this question by introducing a new method called AutoPeriod of Surprisal (APS). APS adopts a canonical periodicity detection algorithm and is able to identify any significant periods that exist in the surprisal sequence of a single document. By applying the algorithm to a set of corpora, we have obtained the following interesting results: Firstly, a considerable proportion of human language demonstrates a strong pattern of periodicity in information; Secondly, new periods that are outside the distributions of typical structural units in text (e.g., sentence boundaries, elementary discourse units, etc.) are found and further confirmed via harmonic regression modeling. We conclude that the periodicity of information in language is a joint outcome from both structured factors and other driving factors that take effect at longer distances. The advantages of our periodicity detection method and its potentials in LLM-generation detection are further discussed.}}, author = {{Ou, Yulin and Wang, Yu and Xu, Yang and Buschmeier, Hendrik}}, booktitle = {{Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics}}, location = {{San Diego, CA, USA}}, pages = {{1161--1175}}, publisher = {{Association for Computational Linguistics}}, title = {{{Identifying the periodicity of information in natural language}}}, doi = {{10.18653/v1/2026.acl-long.52}}, year = {{2026}}, } @inproceedings{66106, abstract = {{Multimodal backchannels are fundamental to conversational grounding and understanding. However, backchannels do not always transparently reflect the interlocutor's actual cognitive state. “Incongruent backchannels”, where the observable feedback implies understanding although there is no genuine understanding, are a potential source of ambiguity in any interaction. Using acoustic, head movement, and discourse-related data from 45 naturalistic dyadic interactions, we investigate whether incongruent and congruent backchannels show systematically different properties using a classification task. Results show that these backchannels are indeed separable based on multimodal features. Incongruent backchannels are typically characterised by more neutral head movement configurations and lower acoustic dynamism, while discursive cues strongly influence the classification. Overall, the findings suggest a relatively reduced effort in the signalling of incongruent backchannels.}}, author = {{Türk, Olcay and Lazarov, Stefan Teodorov and Wang, Yu and Grimminger, Angela and Buschmeier, Hendrik and Wagner, Petra}}, booktitle = {{Proceedings of INTERSPEECH 2026}}, location = {{Sydney, Australia}}, title = {{{When “yeah” means “not quite”: Multimodal detection of backchannels expressing incomplete understanding}}}, year = {{2026}}, } @inproceedings{66610, author = {{Stojko, Laura and Herder, Eelco and Strecker-Bischoff, Jannis and Sänger, Julia Seitz and Neumayr, Thomas and Yigitbas, Enes and Augstein, Mirjam}}, booktitle = {{Companion Publication of the 2026 18th ACM Web Science Conference, WebSci Companion 2026, Braunschweig, Germany, May 26-29, 2026}}, editor = {{Balke, Wolf-Tilo and Plötzky, Florian and Spaniol, Marc and Herder, Eelco and Manikonda, Lydia and Liu, Haiming and Ibáñez, Luis-Daniel and Rezapour, Rezvaneh}}, pages = {{108–109}}, publisher = {{ACM}}, title = {{{ABIS 2026: The Effects of the Adaptive Web on Society}}}, doi = {{10.1145/3795513.3810983}}, year = {{2026}}, } @article{66665, abstract = {{Multimode quantum light has promising applications in many areas of physics, such as quantum communications and quantum computing. However, its multimode nature also makes it challenging to measure its properties. Recently [I. Barakat et al., Optica Quantum 3, 36 (2025)], a technique for the simultaneous measurement of squeezing of multiple broadband modes based on a phase-sensitive amplification approach was experimentally implemented using a setup that effectively corresponds to an SU(1,1) interferometer. Here, we aim to provide a complete theoretical analysis of the modal structure of (generally unbalanced) SU(1,1) interferometers and a detailed theoretical formal derivation of the framework for this technique. Utilizing the joint Schmidt decomposition of the transfer functions, we investigate the shape and phase profiles of the modes of the SU(1,1) interferometer and its components [parametric down-conversion (PDC) sections] for different parametric gain regimes. We discover a complicated interplay between the PDC modes and the modes of the entire interferometer, and analyze it by using their overlap coefficients as a similarity measure. Finally, we develop a rigorous processing method for the aforementioned multimode squeezing measurement technique and discuss necessary approximations to make this method experimentally feasible.}}, author = {{Scharwald, Dennis and Sharapova, Polina}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, number = {{3}}, publisher = {{American Physical Society (APS)}}, title = {{{Characterization of spatial Schmidt modes in high-gain SU(1,1) interferometers}}}, doi = {{10.1103/ph64-ts39}}, volume = {{8}}, year = {{2026}}, } @inproceedings{59835, author = {{Hustermeier, Lennart and Yigitbas, Enes}}, booktitle = {{Proceedings of the 20th IFIP TC13 International Conference on Human-Computer Interaction (INTERACT 2025)}}, publisher = {{Springer}}, title = {{{A Novel Approach for Controlling Drone Swarms: Integrating LLMs and Augmented Reality}}}, year = {{2025}}, } @inproceedings{59833, author = {{Wüppelmann, Dennis and Yigitbas, Enes}}, booktitle = {{Proceedings of the 29th International Conference on Evaluation and Assessment in Software Engineering (EASE 2025)}}, publisher = {{ACM}}, title = {{{SecCityVR: Visualization and Collaborative Exploration of Software Vulnerabilities in Virtual Reality}}}, year = {{2025}}, } @inproceedings{59879, author = {{Wüppelmann, Dennis and Krings, Sarah Claudia and Yigitbas, Enes}}, booktitle = {{Proceedings of the 11th International Conference on Virtual Reality (ICVR 2025)}}, publisher = {{IEEE}}, title = {{{SMART-EAT: Towards Sustainable Nutrition Education and Decision Support using XR}}}, year = {{2025}}, }