@article{9688,
  abstract     = {The properties of the interface between solid and melt are key to solidification and melting, as the interfacial free energy introduces a kinetic barrier to phase transitions. This makes solidification happen below the melting temperature, in out-of-equilibrium conditions at which the interfacial free energy is ill defined. Here we draw a connection between the atomistic description of a diffuse solid-liquid interface and its thermodynamic characterization. This framework resolves the ambiguities in defining the solid-liquid interfacial free energy above and below the melting temperature. In addition, we introduce a simulation protocol that allows solid-liquid interfaces to be reversibly created and destroyed at conditions relevant for experiments. We directly evaluate the value of the interfacial free energy away from the melting point for a simple but realistic atomic potential, and find a more complex temperature dependence than the constant positive slope that has been generally assumed based on phenomenological considerations and that has been used to interpret experiments. This methodology could be easily extended to the study of other phase transitions, from condensation to precipitation. Our analysis can help reconcile the textbook picture of classical nucleation theory with the growing body of atomistic studies and mesoscale models of solidification.},
  author       = {Cheng, Bingqing and Tribello, Gareth A. and Ceriotti, Michele},
  issn         = {1550-235X},
  journal      = {Physical Review B - Condensed Matter and Materials Physics},
  number       = {18},
  publisher    = {American Physical Society},
  title        = {{Solid-liquid interfacial free energy out of equilibrium}},
  doi          = {10.1103/physrevb.92.180102},
  volume       = {92},
  year         = {2015},
}

@inproceedings{11837,
  abstract     = {Online social networks allow the collection of large amounts of data about the influence between users connected by a friendship-like relationship. When distributing items among agents forming a social network, this information allows us to exploit network externalities that each agent receives from his neighbors that get the same item. In this paper we consider Friends-of-Friends (2-hop) network externalities, i.e., externalities that not only depend on the neighbors that get the same item but also on neighbors of neighbors. For these externalities we study a setting where multiple different items are assigned to unit-demand agents. Specifically, we study the problem of welfare maximization under different types of externality functions. Let n be the number of agents and m be the number of items. Our contributions are the following: (1) We show that welfare maximization is APX-hard; we show that even for step functions with 2-hop (and also with 1-hop) externalities it is NP-hard to approximate social welfare better than (1-1/e). (2) On the positive side we present (i) an O(sqrt n)-approximation algorithm for general concave externality functions,
(ii) an O(\log m)-approximation algorithm for linear externality functions, and (iii) an (1-1/e)\frac{1}{6}-approximation algorithm for 2-hop step function externalities. We also improve the result from [6] for 1-hop step function externalities by giving a (1-1/e)/2-approximation algorithm.},
  author       = {Bhattacharya, Sayan and Dvorák, Wolfgang and Henzinger, Monika H and Starnberger,  Martin},
  booktitle    = {32nd International Symposium on Theoretical Aspects of Computer Science},
  isbn         = {978-3-939897-78-1},
  issn         = {1868-8969},
  location     = {Garching, Germany},
  pages        = {90--102},
  publisher    = {Schloss Dagstuhl - Leibniz-Zentrum für Informatik},
  title        = {{Welfare maximization with friends-of-friends network externalities}},
  doi          = {10.4230/LIPICS.STACS.2015.90},
  volume       = {30},
  year         = {2015},
}

@article{11845,
  abstract     = {Phylogenetic diversity (PD) is a measure of biodiversity based on the evolutionary history of species. Here, we discuss several optimization problems related to the use of PD, and the more general measure split diversity (SD), in conservation prioritization.
Depending on the conservation goal and the information available about species, one can construct optimization routines that incorporate various conservation constraints. We demonstrate how this information can be used to select sets of species for conservation action. Specifically, we discuss the use of species' geographic distributions, the choice of candidates under economic pressure, and the use of predator–prey interactions between the species in a community to define viability constraints.
Despite such optimization problems falling into the area of NP hard problems, it is possible to solve them in a reasonable amount of time using integer programming. We apply integer linear programming to a variety of models for conservation prioritization that incorporate the SD measure.
We exemplarily show the results for two data sets: the Cape region of South Africa and a Caribbean coral reef community. Finally, we provide user-friendly software at http://www.cibiv.at/software/pda.},
  author       = {Chernomor, Olga and Minh, Bui Quang and Forest, Félix and Klaere, Steffen and Ingram, Travis and Henzinger, Monika H and von Haeseler, Arndt},
  issn         = {2041-210X},
  journal      = {Methods in Ecology and Evolution},
  number       = {1},
  pages        = {83--91},
  publisher    = {Wiley},
  title        = {{Split diversity in constrained conservation prioritization using integer linear programming}},
  doi          = {10.1111/2041-210x.12299},
  volume       = {6},
  year         = {2015},
}

@inproceedings{11868,
  abstract     = {Consider the following Online Boolean Matrix-Vector Multiplication problem: We are given an n x n matrix M and will receive n column-vectors of size n, denoted by v1, ..., vn, one by one. After seeing each vector vi, we have to output the product Mvi before we can see the next vector. A naive algorithm can solve this problem using O(n3) time in total, and its running time can be slightly improved to O(n3/log2 n) [Williams SODA'07]. We show that a conjecture that there is no truly subcubic (O(n3-ε)) time algorithm for this problem can be used to exhibit the underlying polynomial time hardness shared by many dynamic problems. For a number of problems, such as subgraph connectivity, Pagh's problem, d-failure connectivity, decremental single-source shortest paths, and decremental transitive closure, this conjecture implies tight hardness results. Thus, proving or disproving this conjecture will be very interesting as it will either imply several tight unconditional lower bounds or break through a common barrier that blocks progress with these problems. This conjecture might also be considered as strong evidence against any further improvement for these problems since refuting it will imply a major breakthrough for combinatorial Boolean matrix multiplication and other long-standing problems if the term "combinatorial algorithms" is interpreted as "Strassen-like algorithms" [Ballard et al. SPAA'11].

The conjecture also leads to hardness results for problems that were previously based on diverse problems and conjectures -- such as 3SUM, combinatorial Boolean matrix multiplication, triangle detection, and multiphase -- thus providing a uniform way to prove polynomial hardness results for dynamic algorithms; some of the new proofs are also simpler or even become trivial. The conjecture also leads to stronger and new, non-trivial, hardness results, e.g., for the fully-dynamic densest subgraph and diameter problems.},
  author       = {Henzinger, Monika H and Krinninger, Sebastian and Nanongkai, Danupon and Saranurak, Thatchaphol},
  booktitle    = {47th Annual ACM Symposium on Theory of Computing},
  isbn         = {978-145033536-2},
  issn         = {0737.8017},
  location     = {Portland, OR, United States},
  publisher    = {Association for Computing Machinery},
  title        = {{Unifying and strengthening hardness for dynamic problems via the online matrix-vector multiplication conjecture}},
  doi          = {10.1145/2746539.2746609},
  year         = {2015},
}

@inproceedings{11869,
  abstract     = {While in many graph mining applications it is crucial to handle a stream of updates efficiently in terms of both time and space, not much was known about achieving such type of algorithm. In this paper we study this issue for a problem which lies at the core of many graph mining applications called densest subgraph problem. We develop an algorithm that achieves time- and space-efficiency for this problem simultaneously. It is one of the first of its kind for graph problems to the best of our knowledge.

Given an input graph, the densest subgraph is the subgraph that maximizes the ratio between the number of edges and the number of nodes. For any ε>0, our algorithm can, with high probability, maintain a (4+ε)-approximate solution under edge insertions and deletions using ~O(n) space and ~O(1) amortized time per update; here, $n$ is the number of nodes in the graph and ~O hides the O(polylog_{1+ε} n) term. The approximation ratio can be improved to (2+ε) with more time. It can be extended to a (2+ε)-approximation sublinear-time algorithm and a distributed-streaming algorithm. Our algorithm is the first streaming algorithm that can maintain the densest subgraph in one pass. Prior to this, no algorithm could do so even in the special case of an incremental stream and even when there is no time restriction. The previously best algorithm in this setting required O(log n) passes [BahmaniKV12]. The space required by our algorithm is tight up to a polylogarithmic factor.},
  author       = {Bhattacharya, Sayan and Henzinger, Monika H and Nanongkai, Danupon and Tsourakakis, Charalampos},
  booktitle    = {47th Annual ACM Symposium on Theory of Computing},
  isbn         = {978-145033536-2},
  issn         = {0737-8017},
  location     = {Portland, OR, United States},
  pages        = {173 -- 182},
  publisher    = {Association for Computing Machinery},
  title        = {{Space- and time-efficient algorithm for maintaining dense subgraphs on one-pass dynamic streams}},
  doi          = {10.1145/2746539.2746592},
  year         = {2015},
}

@article{11901,
  abstract     = {We consider auctions of indivisible items to unit-demand bidders with budgets. This setting was suggested as an expressive model for single sponsored search auctions. Prior work presented mechanisms that compute bidder-optimal outcomes and are truthful for a restricted set of inputs, i.e., inputs in so-called general position. This condition is easily violated. We provide the first mechanism that is truthful in expectation for all inputs and achieves for each bidder no worse utility than the bidder-optimal outcome. Additionally we give a complete characterization for which inputs mechanisms that compute bidder-optimal outcomes are truthful.},
  author       = {Henzinger, Monika H and Loitzenbauer, Veronika},
  issn         = {0304-3975},
  journal      = {Theoretical Computer Science},
  pages        = {1--15},
  publisher    = {Elsevier},
  title        = {{Truthful unit-demand auctions with budgets revisited}},
  doi          = {10.1016/j.tcs.2015.01.033},
  volume       = {573},
  year         = {2015},
}

@article{121,
  abstract     = {We show that the simplest building blocks of origami-based materials - rigid, degree-four vertices - are generically multistable. The existence of two distinct branches of folding motion emerging from the flat state suggests at least bistability, but we show how nonlinearities in the folding motions allow generic vertex geometries to have as many as five stable states. In special geometries with collinear folds and symmetry, more branches emerge leading to as many as six stable states. Tuning the fold energy parameters, we show how monostability is also possible. Finally, we show how to program the stability features of a single vertex into a periodic fold tessellation. The resulting metasheets provide a previously unanticipated functionality - tunable and switchable shape and size via multistability.},
  author       = {Waitukaitis, Scott R and Menaut, Rémi and Chen, Bryan and Van Hecke, Martin},
  journal      = {APS Physics, Physical Review Letters},
  number       = {5},
  publisher    = {American Physical Society},
  title        = {{Origami multistability: From single vertices to metasheets}},
  doi          = {10.1103/PhysRevLett.114.055503},
  volume       = {114},
  year         = {2015},
}

@article{12626,
  abstract     = {Ice cliffs have been identified as a reason for higher ablation rates on debris-covered glaciers than are implied by the insulation effects of the debris. This study aims to improve our understanding of cliff backwasting, and the role of radiative fluxes in particular. An energy-balance model is forced with new data gathered in May and October 2013 on Lirung Glacier, Nepalese Himalaya. Observations show substantial variability in melt between cliffs, between locations on any cliff and between seasons. Using a high-resolution digital elevation model we calculate longwave fluxes incident to the cliff from surrounding terrain and include the effect of local shading on shortwave radiation. This is an advance over previous studies, that made simplified assumptions on cliff geometry and radiative fluxes. Measured melt rates varied between 3.25 and 8.6 cm d−1 in May and 0.18 and 1.34 cm d−1 in October. Model results reproduce the strong variability in space and time, suggesting considerable differences in radiative fluxes over one cliff. In October the model fails to reproduce stake readings, probably due to the lack of a refreezing component. Disregarding local topography can lead to overestimation of melt at the point scale by up to ∼9%.},
  author       = {Steiner, Jakob F. and Pellicciotti, Francesca and Buri, Pascal and Miles, Evan S. and Immerzeel, Walter W. and Reid, Tim D.},
  issn         = {1727-5652},
  journal      = {Journal of Glaciology},
  number       = {229},
  pages        = {889--907},
  publisher    = {International Glaciological Society},
  title        = {{Modelling ice-cliff backwasting on a debris-covered glacier in the Nepalese Himalaya}},
  doi          = {10.3189/2015jog14j194},
  volume       = {61},
  year         = {2015},
}

@article{12627,
  abstract     = {Spatial evolution of supraglacial debris cover on mountain glaciers is a largely unmonitored and poorly understood phenomenon that directly affects glacier melt. Supraglacial debris cover for 93 glaciers in the Karakoram, northern Pakistan, was mapped from Landsat imagery acquired in 1977, 1998, 2009 and 2014. Surge-type glaciers occupy 41% of the study area and were considered separately. The time series of debris-covered surface area change shows a mean value of zero or near-zero change for both surging and non-surging glaciers. An increase in debris-covered area is often associated with negative regional mass balances. We extend this logic to suggest that the stable regional mass balances in the Karakoram explain the zero or near-zero change in debris-covered area. This coupling of trends combined with our 37 year time series of data suggests the Karakoram anomaly extends further back in time than previously known.},
  author       = {Herreid, Sam and Pellicciotti, Francesca and Ayala, Alvaro and Chesnokova, Anna and Kienholz, Christian and Shea, Joseph and Shrestha, Arun},
  issn         = {1727-5652},
  journal      = {Journal of Glaciology},
  number       = {227},
  pages        = {524--536},
  publisher    = {International Glaciological Society},
  title        = {{Satellite observations show no net change in the percentage of supraglacial debris-covered area in northern Pakistan from 1977 to 2014}},
  doi          = {10.3189/2015jog14j227},
  volume       = {61},
  year         = {2015},
}

@article{12628,
  abstract     = {Thick debris cover on glaciers can significantly reduce ice melt. However, several studies have suggested that debris-covered glaciers in the Himalaya might have lost mass at a rate similar to debris-free glaciers. We reconstruct elevation and mass changes for the debris-covered glaciers of the upper Langtang valley, Nepalese Himalaya, using a digital elevation model (DEM) from 1974 stereo Hexagon satellite data and the 2000 SRTM (Shuttle Radar Topography Mission) DEM. Uncertainties are high in the accumulation areas, due to data gaps in the SRTM and difficulties with delineation of the glacier borders. Even with these uncertainties, we obtain thinning rates comparable to those of several other studies in the Himalaya. In particular, we obtain a total mass balance for the investigated debris-covered glaciers of the basin of –0.32 ± 0.18 m w.e. a<jats:sup>−1</jats:sup>. However, there are major spatial differences both between glaciers and within any single glacier, exhibiting a very distinct nonlinear mass-balance profile with elevation. Through analysis of surface velocities derived from Landsat ETM+ imagery, we show that thinning occurs in areas of low velocity and low slope. These areas are prone to a general, dynamic decay of surface features and to the development of supraglacial lakes and ice cliffs, which may be responsible for a considerable increase in overall glacier ablation.},
  author       = {Pellicciotti, Francesca and Stephan, Christa and Miles, Evan and Herreid, Sam and Immerzeel, Walter W. and Bolch, Tobias},
  issn         = {1727-5652},
  journal      = {Journal of Glaciology},
  keywords     = {Earth-Surface Processes},
  number       = {226},
  pages        = {373--386},
  publisher    = {International Glaciological Society},
  title        = {{Mass-balance changes of the debris-covered glaciers in the Langtang Himal, Nepal, from 1974 to 1999}},
  doi          = {10.3189/2015jog13j237},
  volume       = {61},
  year         = {2015},
}

@article{12629,
  abstract     = {Meteorological studies in high-mountain environments form the basis of our understanding of catchment hydrology and glacier accumulation and melt processes, yet high-altitude (>4000 m above sea level, asl) observatories are rare. This research presents meteorological data recorded between December 2012 and November 2013 at seven stations in Nepal, ranging in elevation from 3860 to 5360 m asl. Seasonal and diurnal cycles in air temperature, vapour pressure, incoming short-wave and long-wave radiation, atmospheric transmissivity, wind speed, and precipitation are compared between sites. Solar radiation strongly affects diurnal temperature and vapour pressure cycles, but local topography and valley-scale circulations alter wind speed and precipitation cycles. The observed diurnal variability in vertical temperature gradients in all seasons highlights the importance of in situ measurements for melt modelling. The monsoon signal (progressive onset and sharp end) is visible in all data-sets, and the passage of the remnants of Typhoon Phailin in mid-October 2013 provides an interesting case study on the possible effects of such storms on glaciers in the region.},
  author       = {Shea, J.M. and Wagnon, P. and Immerzeel, W.W. and Biron, R. and Brun, F. and Pellicciotti, Francesca},
  issn         = {1360-0648},
  journal      = {International Journal of Water Resources Development},
  keywords     = {Water Science and Technology, Development},
  number       = {2},
  pages        = {174--200},
  publisher    = {Taylor & Francis},
  title        = {{A comparative high-altitude meteorological analysis from three catchments in the Nepalese Himalaya}},
  doi          = {10.1080/07900627.2015.1020417},
  volume       = {31},
  year         = {2015},
}

@inproceedings{12881,
  author       = {Martius, Georg S and Olbrich, Eckehard},
  booktitle    = {Proceedings of the 13th European Conference on Artificial Life},
  isbn         = {9780262330275},
  location     = {York, United Kingdom},
  pages        = {78},
  publisher    = {MIT Press},
  title        = {{Quantifying self-organizing behavior of autonomous robots}},
  doi          = {10.7551/978-0-262-33027-5-ch018},
  year         = {2015},
}

@misc{9719,
  abstract     = {Parasitism creates selection for resistance mechanisms in host populations and is hypothesized to promote increased host evolvability. However, the influence of these traits on host evolution when parasites are no longer present is unclear. We used experimental evolution and whole-genome sequencing of Escherichia coli to determine the effects of past and present exposure to parasitic viruses (phages) on the spread of mutator alleles, resistance, and bacterial competitive fitness. We found that mutator alleles spread rapidly during adaptation to any of four different phage species, and this pattern was even more pronounced with multiple phages present simultaneously. However, hypermutability did not detectably accelerate adaptation in the absence of phages and recovery of fitness costs associated with resistance. Several lineages evolved phage resistance through elevated mucoidy, and during subsequent evolution in phage-free conditions they rapidly reverted to nonmucoid, phage-susceptible phenotypes. Genome sequencing revealed that this phenotypic reversion was achieved by additional genetic changes rather than by genotypic reversion of the initial resistance mutations. Insertion sequence (IS) elements played a key role in both the acquisition of resistance and adaptation in the absence of parasites; unlike single nucleotide polymorphisms, IS insertions were not more frequent in mutator lineages. Our results provide a genetic explanation for rapid reversion of mucoidy, a phenotype observed in other bacterial species including human pathogens. Moreover, this demonstrates that the types of genetic change underlying adaptation to fitness costs, and consequently the impact of evolvability mechanisms such as increased point-mutation rates, depend critically on the mechanism of resistance.},
  author       = {Wielgoss, Sébastien and Bergmiller, Tobias and Bischofberger, Anna M. and Hall, Alex R.},
  publisher    = {Dryad},
  title        = {{Data from: Adaptation to parasites and costs of parasite resistance in mutator and non-mutator bacteria}},
  doi          = {10.5061/dryad.cj910},
  year         = {2015},
}

@misc{9721,
  abstract     = {To prevent epidemics, insect societies have evolved collective disease defences that are highly effective at curing exposed individuals and limiting disease transmission to healthy group members. Grooming is an important sanitary behaviour—either performed towards oneself (self-grooming) or towards others (allogrooming)—to remove infectious agents from the body surface of exposed individuals, but at the risk of disease contraction by the groomer. We use garden ants (Lasius neglectus) and the fungal pathogen Metarhizium as a model system to study how pathogen presence affects self-grooming and allogrooming between exposed and healthy individuals. We develop an epidemiological SIS model to explore how experimentally observed grooming patterns affect disease spread within the colony, thereby providing a direct link between the expression and direction of sanitary behaviours, and their effects on colony-level epidemiology. We find that fungus-exposed ants increase self-grooming, while simultaneously decreasing allogrooming. This behavioural modulation seems universally adaptive and is predicted to contain disease spread in a great variety of host–pathogen systems. In contrast, allogrooming directed towards pathogen-exposed individuals might both increase and decrease disease risk. Our model reveals that the effect of allogrooming depends on the balance between pathogen infectiousness and efficiency of social host defences, which are likely to vary across host–pathogen systems.},
  author       = {Theis, Fabian and Ugelvig, Line V and Marr, Carsten and Cremer, Sylvia},
  publisher    = {Dryad},
  title        = {{Data from: Opposing effects of allogrooming on disease transmission in ant societies}},
  doi          = {10.5061/dryad.dj2bf},
  year         = {2015},
}

@misc{9742,
  abstract     = {Repeated pathogen exposure is a common threat in colonies of social insects, posing selection pressures on colony members to respond with improved disease-defense performance. We here tested whether experience gained by repeated tending of low-level fungus-exposed (Metarhizium robertsii) larvae may alter the performance of sanitary brood care in the clonal ant, Platythyrea punctata. We trained ants individually over nine consecutive trials to either sham-treated or fungus-exposed larvae. We then compared the larval grooming behavior of naive and trained ants and measured how effectively they removed infectious fungal conidiospores from the fungus-exposed larvae. We found that the ants changed the duration of larval grooming in response to both, larval treatment and their level of experience: (1) sham-treated larvae received longer grooming than the fungus-exposed larvae and (2) trained ants performed less self-grooming but longer larval grooming than naive ants, which was true for both, ants trained to fungus-exposed and also to sham-treated larvae. Ants that groomed the fungus-exposed larvae for longer periods removed a higher number of fungal conidiospores from the surface of the fungus-exposed larvae. As experienced ants performed longer larval grooming, they were more effective in fungal removal, thus making them better caretakers under pathogen attack of the colony. By studying this clonal ant, we can thus conclude that even in the absence of genetic variation between colony members, differences in experience levels of brood care may affect performance of sanitary brood care in social insects.},
  author       = {Westhus, Claudia and Ugelvig, Line V and Tourdot, Edouard and Heinze, Jürgen and Doums, Claudie and Cremer, Sylvia},
  publisher    = {Dryad},
  title        = {{Data from: Increased grooming after repeated brood care provides sanitary benefits in a clonal ant}},
  doi          = {10.5061/dryad.7kc79},
  year         = {2015},
}

@article{981,
  abstract     = {The tunability of topological surface states and controllable opening of the Dirac gap are of fundamental and practical interest in the field of topological materials. In the newly discovered topological crystalline insulators (TCIs), theory predicts that the Dirac node is protected by a crystalline symmetry and that the surface state electrons can acquire a mass if this symmetry is broken. Recent studies have detected signatures of a spontaneously generated Dirac gap in TCIs; however, the mechanism of mass formation remains elusive. In this work, we present scanning tunnelling microscopy (STM) measurements of the TCI Pb 1â'x Sn x Se for a wide range of alloy compositions spanning the topological and non-topological regimes. The STM topographies reveal a symmetry-breaking distortion on the surface, which imparts mass to the otherwise massless Dirac electrons-a mechanism analogous to the long sought-after Higgs mechanism in particle physics. Interestingly, the measured Dirac gap decreases on approaching the trivial phase, whereas the magnitude of the distortion remains nearly constant. Our data and calculations reveal that the penetration depth of Dirac surface states controls the magnitude of the Dirac mass. At the limit of the critical composition, the penetration depth is predicted to go to infinity, resulting in zero mass, consistent with our measurements. Finally, we discover the existence of surface states in the non-topological regime, which have the characteristics of gapped, double-branched Dirac fermions and could be exploited in realizing superconductivity in these materials.},
  author       = {Zeljkovic, Ilija and Okada, Yoshinori and Maksym Serbyn and Sankar, Raman and Walkup, Daniel and Zhou, Wenwen and Liu, Junwei and Chang, Guoqing and Wang, Yungjui and Hasan, Md Z and Chou, Fangcheng and Lin, Hsin and Bansil, Arun and Fu, Liang and Madhavan, Vidya},
  journal      = {Nature Materials},
  number       = {3},
  pages        = {318 -- 324},
  publisher    = {Nature Publishing Group},
  title        = {{Dirac mass generation from crystal symmetry breaking on the surfaces of topological crystalline insulators}},
  doi          = {10.1038/nmat4215},
  volume       = {14},
  year         = {2015},
}

@article{982,
  abstract     = {We propose a new approach to probing ergodicity and its breakdown in one-dimensional quantum manybody systems based on their response to a local perturbation. We study the distribution of matrix elements of a local operator between the system's eigenstates, finding a qualitatively different behavior in the manybody localized (MBL) and ergodic phases. To characterize how strongly a local perturbation modifies the eigenstates, we introduce the parameter g(L) = (In (Vnm/δ)) which represents the disorder-averaged ratio of a typical matrix element of a local operator V to energy level spacing δ this parameter is reminiscent of the Thouless conductance in the single-particle localization. We show that the parameter g(L) decreases with system size L in the MBL phase and grows in the ergodic phase. We surmise that the delocalization transition occurs when g(L) is independent of system size, g(L)=gc ~ 1. We illustrate our approach by studying the many-body localization transition and resolving the many-body mobility edge in a disordered one-dimensional XXZ spin-1=2 chain using exact diagonalization and time-evolving block-decimation methods. Our criterion for the MBL transition gives insights into microscopic details of transition. Its direct physical consequences, in particular, logarithmically slow transport at the transition and extensive entanglement entropy of the eigenstates, are consistent with recent renormalization-group predictions.},
  author       = {Maksym Serbyn and Papić, Zlatko and Abanin, Dmitry A},
  journal      = {Physical Review X},
  number       = {4},
  publisher    = {American Physical Society},
  title        = {{Criterion for many-body localization-delocalization phase transition}},
  doi          = {10.1103/PhysRevX.5.041047},
  volume       = {5},
  year         = {2015},
}

@article{99,
  abstract     = {Quasiparticle excitations can compromise the performance of superconducting devices, causing high-frequency dissipation, decoherence in Josephson qubits, and braiding errors in proposed Majorana-based topological quantum computers. Quasiparticle dynamics have been studied in detail in metallic superconductors but remain relatively unexplored in semiconductor-superconductor structures, which are now being intensely pursued in the context of topological superconductivity. To this end, we use a system comprising a gate-confined semiconductor nanowire with an epitaxially grown superconductor layer, yielding an isolated, proximitized nanowire segment. We identify bound states in the semiconductor by means of bias spectroscopy, determine the characteristic temperatures and magnetic fields for quasiparticle excitations, and extract a parity lifetime (poisoning time) of the bound state in the semiconductor exceeding 10 ms.},
  author       = {Higginbotham, Andrew P and Albrecht, S M and Kiršanskas, Gediminas and Chang, W and Kuemmeth, Ferdinand and Krogstrup, Peter and Jespersen, Thomas and Nygård, Jesper and Flensberg, Karsten and Marcus, Charles},
  journal      = {Nature Physics},
  number       = {12},
  pages        = {1017 -- 1021},
  publisher    = {Nature Publishing Group},
  title        = {{Parity lifetime of bound states in a proximitized semiconductor nanowire}},
  doi          = {10.1038/nphys3461},
  volume       = {11},
  year         = {2015},
}

@article{388,
  abstract     = {We use ultrafast optical spectroscopy to observe binding of charged single-particle excitations (SE) in the magnetically frustrated Mott insulator Na2IrO3. Above the antiferromagnetic ordering temperature (TN) the system response is due to both Hubbard excitons (HE) and their constituent unpaired SE. The SE response becomes strongly suppressed immediately below TN. We argue that this increase in binding energy is due to a unique interplay between the frustrated Kitaev and the weak Heisenberg-type ordering term in the Hamiltonian, mediating an effective interaction between the spin-singlet SE. This interaction grows with distance causing the SE to become trapped in the HE, similar to quark confinement inside hadrons. This binding of charged particles, induced by magnetic ordering, is a result of a confinement-deconfinement transition of spin excitations. This observation provides evidence for spin liquid type behavior which is expected in Na2IrO3.},
  author       = {Alpichshev, Zhanybek and Mahmood, Fahad and Cao, Gang and Gedik, Nuh},
  journal      = {Physical Review Letters},
  number       = {1},
  publisher    = {American Physical Society},
  title        = {{Confinement deconfinement transition as an indication of spin liquid type behavior in Na2IrO3}},
  doi          = {10.1103/PhysRevLett.114.017203},
  volume       = {114},
  year         = {2015},
}

@article{248,
  abstract     = {For any pencil of conics or higher-dimensional quadrics over ℚ, with all degenerate fibres defined over ℚ, we show that the Brauer–Manin obstruction controls weak approximation. The proof is based on the Hasse principle and weak approximation for some special intersections of quadrics over ℚ, which is a consequence of recent advances in additive combinatorics.},
  author       = {Timothy Browning and Matthiesen, Lilian and Skorobogatov, Alexei N},
  journal      = {Annals of Mathematics},
  number       = {1},
  pages        = {381 -- 402},
  publisher    = {John Hopkins University Press},
  title        = {{Rational points on pencils of conics and quadrics with many degenerate fibres}},
  doi          = {https://doi.org/10.4007/annals.2014.180.1.8},
  volume       = {180},
  year         = {2014},
}