503 research outputs found
Generalized Color Codes Supporting Non-Abelian Anyons
We propose a generalization of the color codes based on finite groups .
For non-abelian groups, the resulting model supports non-abelian anyonic
quasiparticles and topological order. We examine the properties of these models
such as their relationship to Kitaev quantum double models, quasiparticle
spectrum, and boundary structure.Comment: 17 pages, 8 figures; references added, typos remove
Generalized Cluster States Based on Finite Groups
We define generalized cluster states based on finite group algebras in
analogy to the generalization of the toric code to the Kitaev quantum double
models. We do this by showing a general correspondence between systems with CSS
structure and finite group algebras, and applying this to the cluster states to
derive their generalization. We then investigate properties of these states
including their PEPS representations, global symmetries, and relationship to
the Kitaev quantum double models. We also discuss possible applications of
these states.Comment: 23 pages, 4 figure
Role-playing games
L'origen dels jocs de rol el trobem als EUA de la ma dels seguidors de les novel·les de literatura fantĂ stica. No contents amb ser mers espectadors van voler interpretar i protagonitzar les aventures dels seus personatges preferits. AixĂ cadascun dels participants adaptava per una estona el rol d'algun dels possibles personatges: elfs, orcs, nans, humans, etc. D'aquesta manera i amb l'ajut d'un director de joc que els introduĂŻa en una trama fantĂ stica anaven creant col·lectivament una història, una aventura: la seva aventura.El origen de los juegos de rol lo encontramos en los EE.UU de la mano de los seguidores de las novelas de literatura fantástica. No contentos con ser meros espectadores quisieron interpretar y protagonizar las aventuras de sus personajes preferidos. AsĂ, cada uno de los participantes adaptaba por un rato el rol de alguno de los posibles personajes: elfos, orcos, gnomos, humanos, etc. De esta forma, y con la ayuda de un director de juego que los introducĂa en una trama fantástica iban creando colectivamente una historia, una aventura: su aventura.Role-playing games originated in the USA , and were created by readers of fantasy noves. Not content with being mere spectators, they wanted to interpret and take part in the adventures of their favourite characters. As a result, each participant tempora rily took on the role of one of the possible characters - elves, orcs, gnomes, humans, etc. With the help of a games master who placed them in a fantasy world, they collectively created a story, an adventure - their adventure
Beliefs of Violence-Sensitive and Violence-Tolerant People
Every person views the world through a different lens, and one can never fully understand the motivations and opinions of someone else. However, experiments and statistics can shed some light onto people’s thought patterns and behaviors. When horrific acts of violence occur, many people strive to understand why they happen. Through my study I hope to help solve some of the mysteries behind the different ways people interpret violence. I want to see why some people tend to be more sensitive to violence and why some are more tolerant of violence. I am doing this by building on previous research conducted by Professor Collyer and his colleagues. In their previous studies they analyzed ratings of the severity of various violent acts ranging from life-threatening acts to verbal insults. They found that there are four clusters of violent acts: life threatening acts, low severity physical, high severity nonphysical, and low severity nonphysical. All the participants rated life threatening violence at the same level of severity, but then ratings split into two groups which can be described as: violence sensitive and violence tolerant. The violence-sensitive group had higher ratings of severity for the remaining three clusters of violence than the violence-tolerant group. I have designed a questionnaire which combines the quantitative approach to studying participants used by Professor Collyer, and am taking a qualitative approach by examining the reasons why participants rate these acts of violence with higher ratings or lower ratings. The participants in my study are a group of URI students in a large, introductory psychology course, chosen so as to include a wide variety of students. I am comparing the ratings participants choose for the clusters of violence with their answers to a number of questions about their personal definitions of violence and their attitudes toward crime and punishment. Participants will not only be placed into a group based on their ratings, but will also be asked to identify themselves as either violence-sensitive or violence-tolerant
Perturbative 2-body Parent Hamiltonians for Projected Entangled Pair States
We construct parent Hamiltonians involving only local 2-body interactions for
a broad class of Projected Entangled Pair States (PEPS). Making use of
perturbation gadget techniques, we define a perturbative Hamiltonian acting on
the virtual PEPS space with a finite order low energy effective Hamiltonian
that is a gapped, frustration-free parent Hamiltonian for an encoded version of
a desired PEPS. For topologically ordered PEPS, the ground space of the low
energy effective Hamiltonian is shown to be in the same phase as the desired
state to all orders of perturbation theory. An encoded parent Hamiltonian for
the double semion string net ground state is explicitly constructed as a
concrete example.Comment: 26 pages, 4 figures, v2 published versio
A proposal for self-correcting stabilizer quantum memories in 3 dimensions (or slightly less)
We propose a family of local CSS stabilizer codes as possible candidates for
self-correcting quantum memories in 3D. The construction is inspired by the
classical Ising model on a Sierpinski carpet fractal, which acts as a classical
self-correcting memory. Our models are naturally defined on fractal subsets of
a 4D hypercubic lattice with Hausdorff dimension less than 3. Though this does
not imply that these models can be realised with local interactions in 3D
Euclidean space, we also discuss this possibility. The X and Z sectors of the
code are dual to one another, and we show that there exists a finite
temperature phase transition associated with each of these sectors, providing
evidence that the system may robustly store quantum information at finite
temperature.Comment: 16 pages, 6 figures. In v2, erroneous argument about embeddability
into R3 was removed. In v3, minor changes to match journal versio
Automatische Lenksysteme zur UnterstĂĽtzung der mechanischen Beikrautregulierung
Weed management without herbicides in production of field vegetables is very time consuming and therefore costly. After every mechanical treatment a weeding by hand is necessary for a satisfactory weed control. To minimize the weeding automatic
steering systems connected to a shifting frame can support the mechanical weeding by making it more precise and reducing the remaining weeds in the row. Field studies in the year 2016 showed advantages and disadvantages of the systems
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Reconciling dichotomies in higher education : theoretical and practical implications of an interactive educational conception.
Recent decades have witnessed the growing emergence of a conception of higher learning as entailing the interaction of individual tendencies with physical and social conditions. The present study explores the theoretical and practical implications of this conception across several key areas of the literature, including higher education reform, critical thinking, moral education, college writing, and college teaching. Generally speaking, educational interactionism is the attempt to explain intellectual and moral growth in terms of the ongoing and reciprocal interaction of human beings and their physical and social environments. It accordingly seeks to reconcile the historical antipathy between inner-directed theories (rationalism, idealism, romanticism) and outer-directed theories (empiricism, positivism, essentialism) of human agency, meaning, and growth. In terms of educational practice, educational interactionism seeks to resolve the persistent tension between attention to students\u27 individual needs and interests and the transmission of a socially viable body of subject matter. It does so chiefly by asserting that neither has any meaning without the other. In projecting this interactive conception across what are for the most part discrete literatures, the present study seeks to illustrate how similar principles operate across these areas and to encourage dialogue between them. It should be viewed as a first step in a larger effort to integrate and clarify the general features of an interactive educational conception, eliminate many present inconsistencies, and outline its implications for educational policy and teaching practice
Many-body models for topological quantum information
We develop and investigate several quantum many-body spin models of use for topological quantum information processing and storage. These models fall into two categories: those that are designed to be more realistic than alternative models with similar phenomenology, and those that are designed to have richer phenomenology than related models. In the first category, we present a procedure to obtain the Hamiltonians of the toric code and Kitaev quantum double models as the perturbative low-energy limits of entirely two-body Hamiltonians. This construction reproduces the target models' behavior using only couplings which are natural in terms of the original Hamiltonians. As an extension of this work, we construct parent Hamiltonians involving only local 2-body interactions for a broad class of Projected Entangled Pair States (PEPS). We define a perturbative Hamiltonian with a finite order low energy effective Hamiltonian that is a gapped, frustration-free parent Hamiltonian for an encoded version of a desired PEPS. For topologically ordered PEPS, the ground space of the low energy effective Hamiltonian is shown to be in the same phase as the desired state to all orders of perturbation theory. We then move on to define models that generalize the phenomenology of several well-known systems. We first define generalized cluster states based on finite group algebras, and investigate properties of these states including their PEPS representations, global symmetries, relationship to the Kitaev quantum double models, and possible applications. Finally, we propose a generalization of the color codes based on finite groups. For non-Abelian groups, the resulting model supports non-Abelian anyonic quasiparticles and topological order. We examine the properties of these models such as their relationship to Kitaev quantum double models, quasiparticle spectrum, and boundary structure
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