Modeling Pauli measurements on graph states with nearest-neighbor classical communication

We propose a communication-assisted local-hidden-variable model that yields the correct outcome for the measurement of any product of Pauli operators on an arbitrary graph state, i.e., that yields the correct global correlation among the individual measurements in the Pauli product. Within this model, communication is restricted to a single round of message passing between adjacent nodes of the graph. We show that any model sharing some general properties with our own is incapable, for at least some graph states, of reproducing the expected correlations among all subsets of the individual measurements. The ability to reproduce all such correlations is found to depend on both the communication distance and the symmetries of the communication protocol.Comment: 9 pages, 2 figures. Version 2 significantly revised. Now includes a site-invariant protocol for linear chains and a proof that no limited communication protocol can correctly predict all quantum correlations for ring

Graphical description of the action of Clifford operators on stabilizer states

We introduce a graphical representation of stabilizer states and translate the action of Clifford operators on stabilizer states into graph operations on the corresponding stabilizer-state graphs. Our stabilizer graphs are constructed of solid and hollow nodes, with (undirected) edges between nodes and with loops and signs attached to individual nodes. We find that local Clifford transformations are completely described in terms of local complementation on nodes and along edges, loop complementation, and change of node type or sign. Additionally, we show that a small set of equivalence rules generates all graphs corresponding to a given stabilizer state; we do this by constructing an efficient procedure for testing the equality of any two stabilizer graphs.Comment: 14 pages, 8 figures. Version 2 contains significant changes. Submitted to PR

Fault-Tolerant Thresholds for Encoded Ancillae with Homogeneous Errors

I describe a procedure for calculating thresholds for quantum computation as a function of error model given the availability of ancillae prepared in logical states with independent, identically distributed errors. The thresholds are determined via a simple counting argument performed on a single qubit of an infinitely large CSS code. I give concrete examples of thresholds thus achievable for both Steane and Knill style fault-tolerant implementations and investigate their relation to threshold estimates in the literature.Comment: 14 pages, 5 figures, 3 tables; v2 minor edits, v3 completely revised, submitted to PR

Restrictions on Transversal Encoded Quantum Gate Sets

Transversal gates play an important role in the theory of fault-tolerant quantum computation due to their simplicity and robustness to noise. By definition, transversal operators do not couple physical subsystems within the same code block. Consequently, such operators do not spread errors within code blocks and are, therefore, fault tolerant. Nonetheless, other methods of ensuring fault tolerance are required, as it is invariably the case that some encoded gates cannot be implemented transversally. This observation has led to a long-standing conjecture that transversal encoded gate sets cannot be universal. Here we show that the ability of a quantum code to detect an arbitrary error on any single physical subsystem is incompatible with the existence of a universal, transversal encoded gate set for the code.Comment: 4 pages, v2: minor change

Chromosomal control of non-gliadin proteins from the 70% ethanol extract of wheat endosperm

The non-gliadin fraction of the 70% ethanol extracts of compensated nulli-tetrasomics and ditelosomics of Triticum aestivum cv. Chinese Spring has been analyzed by combined electrofocusing and electrophoresis. Seventeen of the 21 protein map components of the euploid have been ascribed to eight chromosomes: 4A, 3BS, 6BS, 7BS, 3D, 4D, 5D and 7DS. The relationship of the different map components with other proteins previously associated with the same chromosomes is discusse

The Remote Learning Experience at Portland State University in Spring 2020

It is an endeavor to understand what we have and will learn about the impact of remote instruction on faculty, students and relevant academic support teams. Simply put: We want to learn from an experiment foisted upon us by a health crisis. We have engaged in an incredibly innovative response. And now, we ask what have we learned? How might we improve? And, most importantly, are there implications from this experiment for the future of instruction at PSU and throughout higher education? The project was organized around two stages in the Spring 2020 term. Stage One: Out of the Gate: Reflections and Lessons Learned (First half of the term) Stage Two: Reaching the Finish Line: Lessons Learned and Recommendations for moving forward (Second half of the term). The project began the week of April 20 and continued through June 12. The original plan called for the following participants: (a) ten undergraduate students to put together a group of 8-10 other students to discuss the questions posed in the study; (b) Three graduate students who would assemble 5-7 fellow graduate students; (c) Three tenured or tenure-track faculty, two non-tenure-track faculty and three adjunct faculty, each of whom would form a chat group of 5-7 other faculty to discuss the questions posed in the study. In addition, Judith Ramaley put together a chat group of a dozen student support unit leaders to explore how each unit adjusted as the university moved quickly to remote learning and remote work and then, in a second round, what lessons each had learned throughout the spring term about ways to support students and assist faculty members who were also seeking to help their students

The Semidwarfs - A New Era in Rice Production.

52 p

Epistemic vs non-epistemic criteria to assess Wikipedia articles: evolution of young people perceptions

This paper tackles the problem of information credibility assessment by users, focusing on Wikipedia articles. We consider both epistemic and non-epistemic criteria. We conducted a study using a questionnaire where 841 French young people aged from 11 to 25 years participated and we analysed the results considering the level of education as a variable. We found that the higher the level of education is, the more young people mention epistemic credibility criteria and the less they indicate non-epistemic criteria. We draw some recommendation for information literacy