@article{AwadMetzler2022, author = {Awad, Emad and Metzler, Ralf}, title = {Closed-form multi-dimensional solutions and asymptotic behaviours for subdiffusive processes with crossovers: II. Accelerating case}, series = {Journal of physics : A, Mathematical and theoretical}, volume = {55}, journal = {Journal of physics : A, Mathematical and theoretical}, number = {20}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {1751-8113}, doi = {10.1088/1751-8121/ac5a90}, pages = {29}, year = {2022}, abstract = {Anomalous diffusion with a power-law time dependence vertical bar R vertical bar(2)(t) similar or equal to t(alpha i) of the mean squared displacement occurs quite ubiquitously in numerous complex systems. Often, this anomalous diffusion is characterised by crossovers between regimes with different anomalous diffusion exponents alpha(i). Here we consider the case when such a crossover occurs from a first regime with alpha(1) to a second regime with alpha(2) such that alpha(2) > alpha(1), i.e., accelerating anomalous diffusion. A widely used framework to describe such crossovers in a one-dimensional setting is the bi-fractional diffusion equation of the so-called modified type, involving two time-fractional derivatives defined in the Riemann-Liouville sense. We here generalise this bi-fractional diffusion equation to higher dimensions and derive its multidimensional propagator (Green's function) for the general case when also a space fractional derivative is present, taking into consideration long-ranged jumps (Levy flights). We derive the asymptotic behaviours for this propagator in both the short- and long-time as well the short- and long-distance regimes. Finally, we also calculate the mean squared displacement, skewness and kurtosis in all dimensions, demonstrating that in the general case the non-Gaussian shape of the probability density function changes.}, language = {en} } @article{CaliendoCobbClarkObstetal.2022, author = {Caliendo, Marco and Cobb-Clark, Deborah A. and Obst, Cosima and Seitz, Helke and Uhlendorff, Arne}, title = {Locus of control and investment in training}, series = {Journal of human resources}, volume = {57}, journal = {Journal of human resources}, number = {4}, publisher = {University of Wisconsin Press}, address = {Madison}, issn = {0022-166X}, doi = {10.3368/jhr.57.4.0318-9377R2}, pages = {1311 -- 1349}, year = {2022}, abstract = {We extend standard models of work-related training by explicitly incorporating workers' locus of control into the investment decision through the returns they expect. Our model predicts that higher internal control results in increased take-up of general, but not specific, training. This prediction is empirically validated using data from the German Socioeconomic Panel (SOEP). We provide empirical evidence that locus of control influences participation in training through its effect on workers' expectations about future wage increases rather than actual wage increases. Our results provide an important explanation for underinvestment in training and suggest that those with an external sense of control may require additional training support.}, language = {en} } @article{BonettoPoundSam2022, author = {Bonetto, Riccardo and Pound, Adam and Sam, Zeyd}, title = {Deformed Schwarzschild horizons in second-order perturbation theory}, series = {Physical review D, Particles, fields, gravitation, and cosmology}, volume = {105}, journal = {Physical review D, Particles, fields, gravitation, and cosmology}, number = {2}, publisher = {American Physical Society}, address = {College Park}, issn = {2470-0010}, doi = {10.1103/PhysRevD.105.024048}, pages = {42}, year = {2022}, abstract = {In recent years, gravitational-wave astronomy has motivated increasingly accurate perturbative studies of gravitational dynamics in compact binaries. This in turn has enabled more detailed analyses of the dynamical black holes in these systems. For example, Pound et al. [Phys. Rev. Lett. 124, 021101 (2020)] recently computed the surface area of a Schwarzschild black hole's apparent horizon, perturbed by an orbiting body, to second order in the binary's mass ratio. In this paper, we take that as the starting point for a comprehensive study of a perturbed Schwarzschild black hole's apparent and event horizon at second perturbative order, deriving generic formulas for the first- and second-order corrections to the horizons' radial profiles, surface areas, Hawking masses, and intrinsic curvatures. We find that the two horizons are remarkably similar, and that any teleological behavior of the event horizon is suppressed in several ways. Critically, we establish that at all orders, the perturbed event horizon in a small-mass-ratio binary is effectively localized in time. Even more pointedly, the event horizon is identical to the apparent horizon at linear order regardless of the source of perturbation, implying that the seemingly teleological "tidal lead," previously observed in linearly perturbed event horizons, is not genuinely teleological in origin. The two horizons do generically differ at second order, but their Hawking masses remain identical, implying that the event horizon obeys the same energy-flux balance law as the apparent horizon. At least in the case of a binary system, the difference between their surface areas remains extremely small even in the late stages of inspiral. In the course of our analysis, we also numerically illustrate puzzling behavior in the black hole's motion around the binary's center of mass.}, language = {en} } @article{FischerWertherBouaklineetal.2022, author = {Fischer, Eric Wolfgang and Werther, Michael and Bouakline, Foudhil and Grossmann, Frank and Saalfrank, Peter}, title = {Non-Markovian vibrational relaxation dynamics at surfaces}, series = {The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr}, volume = {156}, journal = {The journal of chemical physics : bridges a gap between journals of physics and journals of chemistr}, number = {21}, publisher = {AIP Publishing}, address = {Melville}, issn = {0021-9606}, doi = {10.1063/5.0092836}, pages = {16}, year = {2022}, abstract = {Vibrational dynamics of adsorbates near surfaces plays both an important role for applied surface science and as a model lab for studying fundamental problems of open quantum systems. We employ a previously developed model for the relaxation of a D-Si-Si bending mode at a D:Si(100)-(2 x 1) surface, induced by a "bath " of more than 2000 phonon modes [Lorenz and P. Saalfrank, Chem. Phys. 482, 69 (2017)], to extend previous work along various directions. First, we use a Hierarchical Effective Mode (HEM) model [Fischer et al., J. Chem. Phys. 153, 064704 (2020)] to study relaxation of higher excited vibrational states than hitherto done by solving a high-dimensional system-bath time-dependent Schrodinger equation (TDSE). In the HEM approach, (many) real bath modes are replaced by (much less) effective bath modes. Accordingly, we are able to examine scaling laws for vibrational relaxation lifetimes for a realistic surface science problem. Second, we compare the performance of the multilayer multiconfigurational time-dependent Hartree (ML-MCTDH) approach with that of the recently developed coherent-state-based multi-Davydov-D2 Ansatz [Zhou et al., J. Chem. Phys. 143, 014113 (2015)]. Both approaches work well, with some computational advantages for the latter in the presented context. Third, we apply open-system density matrix theory in comparison with basically "exact " solutions of the multi-mode TDSEs. Specifically, we use an open-system Liouville-von Neumann (LvN) equation treating vibration-phonon coupling as Markovian dissipation in Lindblad form to quantify effects beyond the Born-Markov approximation. Published under an exclusive license by AIP Publishing.}, language = {en} } @article{DoerrKoetzing2022, author = {Doerr, Benjamin and K{\"o}tzing, Timo}, title = {Lower bounds from fitness levels made easy}, series = {Algorithmica}, journal = {Algorithmica}, publisher = {Springer}, address = {New York}, issn = {0178-4617}, doi = {10.1007/s00453-022-00952-w}, pages = {29}, year = {2022}, abstract = {One of the first and easy to use techniques for proving run time bounds for evolutionary algorithms is the so-called method of fitness levels by Wegener. It uses a partition of the search space into a sequence of levels which are traversed by the algorithm in increasing order, possibly skipping levels. An easy, but often strong upper bound for the run time can then be derived by adding the reciprocals of the probabilities to leave the levels (or upper bounds for these). Unfortunately, a similarly effective method for proving lower bounds has not yet been established. The strongest such method, proposed by Sudholt (2013), requires a careful choice of the viscosity parameters gamma(i), j, 0 <= i < j <= n. In this paper we present two new variants of the method, one for upper and one for lower bounds. Besides the level leaving probabilities, they only rely on the probabilities that levels are visited at all. We show that these can be computed or estimated without greater difficulties and apply our method to reprove the following known results in an easy and natural way. (i) The precise run time of the (1+1) EA on LEADINGONES. (ii) A lower bound for the run time of the (1+1) EA on ONEMAX, tight apart from an O(n) term. (iii) A lower bound for the run time of the (1+1) EA on long k-paths (which differs slightly from the previous result due to a small error in the latter). We also prove a tighter lower bound for the run time of the (1+1) EA on jump functions by showing that, regardless of the jump size, only with probability O(2(-n)) the algorithm can avoid to jump over the valley of low fitness.}, language = {en} } @article{SchulteLiLisovskietal.2022, author = {Schulte, Luise and Li, Chenzhi and Lisovski, Simeon and Herzschuh, Ulrike}, title = {Forest-permafrost feedbacks and glacial refugia help explain the unequal distribution of larch across continents}, series = {Journal of biogeography}, volume = {49}, journal = {Journal of biogeography}, number = {10}, publisher = {Wiley}, address = {Hoboken}, issn = {0305-0270}, doi = {10.1111/jbi.14456}, pages = {1825 -- 1838}, year = {2022}, abstract = {Aim: The continental-scale distribution of plant functional types, such as evergreen and summergreen needle-leaf forest, is assumed to be determined by contemporary climate. However, the distribution of summergreen needle-leaf forest of larch (Larix Mill.) differs markedly between the continents, despite relatively similar climatic conditions. The reasons for these differences are little understood. Our aim is to identify potential triggers and drivers of the current distribution patterns by comparing species' bioclimatic niches, glacial refugia and postglacial recolonization patterns. Location: Northern hemisphere. Taxon: Species of the genus Larix (Mill.). Methods: We compare species distribution and dominance using species ranges and sites of dominance, as well as their occurrence on modelled permafrost extent, and active layer thickness (ALT). We compare the bioclimatic niches and calculate the niche overlap between species, using the same data in addition to modern climate data. We synthesize pollen, macrofossil and ancient DNA palaeo-evidence of past Larix occurrences of the last 60,000 years and track differences in distribution patterns through time. Results: Bioclimatic niches show large overlaps between Asian larch species and American Larix laricina. The distribution across various degrees of permafrost extent is distinctly different for Asian L. gmelinii and L. cajanderi compared to the other species, whereas the distribution on different depths of ALT is more similar among Asian and American species. Northern glacial refugia for Larix are only present in eastern Asia and Alaska. Main Conclusion: The dominance of summergreen larches in Asia, where evergreen conifers dominate most of the rest of the boreal forests, is dependent on the interaction of several factors which allows Asian L. gmelinii and L. cajanderi to dominate where these factors coincide. These factors include the early postglacial spread out of northern glacial refugia in the absence of competitors as well as a positive feedback mechanism between frozen ground and forest.}, language = {en} } @article{SiegmundPanebiancoAvecillaetal.2022, author = {Siegmund, Nicole and Panebianco, Juan E. and Avecilla, Fernando and Iturri, Laura Antonela and Sommer, Michael and Buschiazzo, Daniel and Funk, Roger}, title = {From gustiness to dustiness}, series = {Atmosphere}, volume = {13}, journal = {Atmosphere}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2073-4433}, doi = {10.3390/atmos13081173}, pages = {14}, year = {2022}, abstract = {This study delivers the first empirical data-driven analysis of the impact of turbulence induced gustiness on the fine dust emissions from a measuring field. For quantification of the gust impact, a new measure, the Gust uptake Efficiency (GuE) is introduced. GuE provides a percentage of over- or under-proportional dust uptake due to gust activity during a wind event. For the three analyzed wind events, GuE values of up to 150\% could be found, yet they significantly differed per particle size class with a tendency for lower values for smaller particles. In addition, a high-resolution correlation analysis among 31 particle size classes and wind speed was conducted; it revealed strong negative correlation coefficients for very small particles and positive correlations for bigger particles, where 5 mu m appears to be an empirical threshold dividing both directions. We conclude with a number of suggestions for further investigations: an optimized field experiment setup, a new particle size ratio (PM1/PM0.5 in addition to PM10/PM2.5), as well as a comprehensive data-driven search for an optimal wind gust definition in terms of soil erosivity.}, language = {en} } @article{BlaesiusFreibergerFriedrichetal.2022, author = {Bl{\"a}sius, Thomas and Freiberger, Cedric and Friedrich, Tobias and Katzmann, Maximilian and Montenegro-Retana, Felix and Thieffry, Marianne}, title = {Efficient Shortest Paths in Scale-Free Networks with Underlying Hyperbolic Geometry}, series = {ACM Transactions on Algorithms}, volume = {18}, journal = {ACM Transactions on Algorithms}, number = {2}, publisher = {Association for Computing Machinery}, address = {New York}, issn = {1549-6325}, doi = {10.1145/3516483}, pages = {1 -- 32}, year = {2022}, abstract = {A standard approach to accelerating shortest path algorithms on networks is the bidirectional search, which explores the graph from the start and the destination, simultaneously. In practice this strategy performs particularly well on scale-free real-world networks. Such networks typically have a heterogeneous degree distribution (e.g., a power-law distribution) and high clustering (i.e., vertices with a common neighbor are likely to be connected themselves). These two properties can be obtained by assuming an underlying hyperbolic geometry.
To explain the observed behavior of the bidirectional search, we analyze its running time on hyperbolic random graphs and prove that it is (O) over tilde (n(2-1/alpha) + n(1/(2 alpha)) + delta(max)) with high probability, where alpha is an element of (1/2, 1) controls the power-law exponent of the degree distribution, and dmax is the maximum degree. This bound is sublinear, improving the obvious worst-case linear bound. Although our analysis depends on the underlying geometry, the algorithm itself is oblivious to it.}, language = {en} } @article{LawrenceWilliamsNanzetal.2022, author = {Lawrence, Mark and Williams, Stephen and Nanz, Patrizia and Renn, Ortwin}, title = {Perspective Characteristics, potentials, and challenges of transdisciplinary research}, series = {One Earth}, volume = {5}, journal = {One Earth}, number = {1}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2590-3322}, doi = {10.1016/j.oneear.2021.12.010}, pages = {44 -- 61}, year = {2022}, abstract = {Resolving the grand challenges and wicked problems of the Anthropocene will require skillfully combining a broad range of knowledge and understandings-both scientific and non-scientific-of Earth systems and human societies. One approach to this is transdisciplinary research, which has gained considerable interest over the last few decades, resulting in an extensive body of literature about transdisciplinarity. However, this has in turn led to the challenge that developing a good understanding of transdisciplinary research can require extensive effort. Here we provide a focused overview and perspective for disciplinary and interdisciplinary researchers who are interested in efficiently obtaining a solid understanding of transdisciplinarity. We describe definitions, characteristics, schools of thought, and an exemplary three-phase model of transdisciplinary research. We also discuss three key challenges that transdisciplinary research faces in the context of addressing the broader challenges of the Anthropocene, and we consider approaches to dealing with these specific challenges, based especially on our experiences with building up transdisciplinary research projects at the Institute for Advanced Sustainability Studies.}, language = {en} } @article{GiraudierVenturaBortWendtetal.2022, author = {Giraudier, Manon and Ventura-Bort, Carlos and Wendt, Julia and Lischke, Alexander and Weymar, Mathias}, title = {Memory advantage for untrustworthy faces}, series = {PLoS one}, volume = {17}, journal = {PLoS one}, number = {2}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0264034}, pages = {11}, year = {2022}, abstract = {The Covid-19 pandemic imposed new constraints on empirical research and forced researchers to transfer from traditional laboratory research to the online environment. This study tested the validity of a web-based episodic memory paradigm by comparing participants' memory performance for trustworthy and untrustworthy facial stimuli in a supervised laboratory setting and an unsupervised web setting. Consistent with previous results, we observed enhanced episodic memory for untrustworthy compared to trustworthy faces. Most importantly, this memory bias was comparable in the online and the laboratory experiment, suggesting that web-based procedures are a promising tool for memory research.}, language = {en} }