Error Analysis For Encoding A Qubit In An Oscillator

In the paper titled "Encoding A Qubit In An Oscillator" Gottesman, Kitaev, and Preskill [quant-ph/0008040] described a method to encode a qubit in the continuous Hilbert space of an oscillator's position and momentum variables. This encoding provides a natural error correction scheme that can correct errors due to small shifts of the position or momentum wave functions (i.e., use of the displacement operator). We present bounds on the size of correctable shift errors when both qubit and ancilla states may contain errors. We then use these bounds to constrain the quality of input qubit and ancilla states.Comment: 5 pages, 8 figures, submitted to Physical Review

Quantum computation with optical coherent states

We show that quantum computation circuits using coherent states as the logical qubits can be constructed from simple linear networks, conditional photon measurements and "small" coherent superposition resource states

360 Cinematic literacy: a case study

360 degree film making necessitates a new language for storytelling. We investigate this issue from the point of view of the user, inferring 360 literacy from what users say about their viewing experiences. The case study is based on material from two user studies on a 360 video profile of an artist. Interviews were analysed using thematic analysis to understand how users made sense of the video. The sense of presence had a strong impact on the experience, while the ability to look around meant new skills had to be developed to try to make sense of 360 video. Viewers had most to say about a few particular shots, and some themes of note emerge: such as being in unusual places, certainty about what should be attended to and focus points, switches between first and third person views, and close-ups and interest

User experience of panoramic video in CAVE-like and head mounted display viewing conditions

Panoramic 360 video is a rapidly growing part of interactive TV viewing experience due to the increase of both production by consumers and professionals and the availability of consumer headsets used to view it. Recent years have also seen proposals for the development of home systems that could ultimately approximate CAVE-like experiences. The question arises as to the nature of the user experience of viewing panoramic video in head mounted displays compared to CAVE-like systems. User preference seems hard to predict. Accordingly, this study took a qualitative approach to describing user experience of viewing a panoramic video on both platforms, using a thematic analysis. Sixteen users tried both viewing conditions and equal numbers expressed preferences for each display system. The differences in user experience by viewing condition are discussed in detail via themes emerging from the analysis

Effects of viewing condition on user experience of panoramic video

Panoramic video arises at the convergence of TV and virtual reality, and it is necessary to understand how these technologies interact to affect user experience in order to produce useful content. TV and film makers have developed a sophisticated language and set of techniques to achieve directed linear story telling on fixed screens, whereas virtual worlds more often emphasise user led exploration of possibly non-linear narrative and aspects such as presence and immersion in navigable 3D environments. This study focused on the user experience of panoramic video as viewed over two conditions, on a VR headset and using a handheld phone, and compared this to watching on a static screen thus emphasising the differences between traditional and panoramic TV. A qualitative approach to analysis was taken where users participated in semi-structured interviews. A thematic analysis was performed which produced thematic maps describing user experience for each condition. A detailed and nuanced account of emerging themes is given. Subsequently, key themes were identified and graphed to produce user response profiles to the three viewing conditions that highlight differences in user experience in terms of presence, attention, engagement, concentration on story, certainty, comfort and social eas

Crossing Chronotopes in the Polyphonic Organisation: A dialogical analysis of the comedy industry

YesThe ‘Polyphonic Organisation’ is an emerging root-metaphor for the multiple voices that constitute an organisation. In this article, we explore the narrative concept of the ‘chronotope’ as a feature of the ‘polyphonic organisation’. The ‘chronotope’, in a general sense, refers to the matrix of time-space-value in organisations. We argue that the chronotope is important because it introduces boundaries between voices within organisations and helps to explain the difficulties in getting to dialogue with voices in different spaces in the ‘Polyphonic Organisation’. More particularly, there are multiple kinds of chronotopes which lead to different kinds of time-spaces matrices within the polyphonic organisation. Our aim is to examine chronotope crossings within polyphonic organisations as part of the work of being heard. This is a theoretical argument drawing significantly from Bakhtin’s work on chronotope. To examine the argument in practice we draw on original fieldwork within the comedy industry. Here we found three kinds of chronotopes: 1) The comedy-offense boundary; 2) The commissioning landscape 3) Platform spaces. We also found that moving within and between these involved a variety of adventures in experience (such as hope and disappointment), which also have their own specific chronotopes. Overall, we argue that the polyphonic organisation is significantly enhanced as an organisational concept through a turn to the role of chronotope. This is because chronotope helpfully describes the barriers and porous boundaries between voice

Entanglement Purification of Any Stabilizer State

We present a method for multipartite entanglement purification of any stabilizer state shared by several parties. In our protocol each party measures the stabilizer operators of a quantum error-correcting code on his or her qubits. The parties exchange their measurement results, detect or correct errors, and decode the desired purified state. We give sufficient conditions on the stabilizer codes that may be used in this procedure and find that Steane's seven-qubit code is the smallest error-correcting code sufficient to purify any stabilizer state. An error-detecting code that encodes two qubits in six can also be used to purify any stabilizer state. We further specify which classes of stabilizer codes can purify which classes of stabilizer states.Comment: 11 pages, 0 figures, comments welcome, submitting to Physical Review