Performing the Network

Séance: a networked glossalalia is a networked performance that is part of the media art project, The Perpetual Emotion Project. Both are animated by our interest in the non-instrumental and the non-sensical and in the making of performative events. In this paper we present the work as practice-led research, which contributes to the understanding and development of what we identify as performative media art. This paper is an expanded version of a paper presented at E-Performance and Plug-ins, UNSW, 2006

A two-qubit Bell inequality for which POVM measurements are relevant

A bipartite Bell inequality is derived which is maximally violated on the two-qubit state space if measurements describable by positive operator valued measure (POVM) elements are allowed rather than restricting the possible measurements to projective ones. In particular, the presented Bell inequality requires POVMs in order to be maximally violated by a maximally entangled two-qubit state. This answers a question raised by N. Gisin.Comment: 7 pages, 1 figur

Spectroscopic Characterization of the Ground and Low-Lying Electronic States of Ga2N via Anion Photoelectron Spectroscopy.

Anion photoelectron spectra of Ga2N− were measured at photodetachment wavelengths of 416nm(2.978eV), 355nm(3.493eV), and 266nm(4.661eV). Both field-free time-of-flight and velocity-map imaging methods were used to collect the data. The field-free time-of-flight data provided better resolution of the features, while the velocity-map-imaging data provided more accurate anisotropy parameters for the peaks. Transitions from the ground electronic state of the anion to two electronic states of the neutral were observed and analyzed with the aid of electronic structure calculations and Franck-Condon simulations. The ground-state band was assigned to a transition between linear ground states of Ga2N−(XΣg+1) and Ga2N(XΣu+2), yielding the electron affinity of Ga2N, 2.506±0.008eV. Vibrationally resolved features in the ground-state band were assigned to symmetric and antisymmetric stretch modes of Ga2N, with the latter allowed by vibronic coupling to an excited electronic state. The energy of the observed excited neutral state agrees with that calculated for the AΠu2 state, but the congested nature of this band in the photoelectron spectrum is more consistent with a transition to a bent neutral state

Neumark Operators and Sharp Reconstructions, the finite dimensional case

A commutative POV measure $F$ with real spectrum is characterized by the existence of a PV measure $E$ (the sharp reconstruction of $F$) with real spectrum such that $F$ can be interpreted as a randomization of $E$. This paper focuses on the relationships between this characterization of commutative POV measures and Neumark's extension theorem. In particular, we show that in the finite dimensional case there exists a relation between the Neumark operator corresponding to the extension of $F$ and the sharp reconstruction of $F$. The relevance of this result to the theory of non-ideal quantum measurement and to the definition of unsharpness is analyzed.Comment: 37 page

The Trouble with the Weather: a southern response

Research Background At a time when global warming was both urgent and overwhelming, there was a dearth of exhibitions dedicated to the issue that made room for audiences to engage in new ways. There was a need to bring together a range of art works that spoke to the issue, to an exhibition space, and to each other in ways that allowed people (new) ways to engage with global warming, to find their own ways of thinking and responding. As global warming was an emotionally and politically overloaded topic, there was a need for non-didactic exhibitions that opened thinking up as to how the uneasy relationship between technology, nature and culture was being unsettled once more. Research Contribution The artists in the Trouble with the Weather responded to weather events and to the weather as event -- psychically, 'pataphysically, emotionally and aesthetically in ways that opened the issue up for audiences. It featured a range of significant southern hemisphere artists including Elizabeth Day, David Haines & Joyce Hinterding (Aus), Jonathan Jones, Zina Kaye, Dani Marti, Janine Randerson, Te Vaka, John Tonkin and H J Wedge. Research Significance The importance of the exhibition (and its catalogue) was demonstrated by the funding it gained from Luca Belgiorno-Nettis, UTS, City of Sydney and the Australia Council for the Arts. It was featured and reviewed in SMH, RealTime and Loop Magazine. "Despite the undercurrent of urgency and desperation in the subject matter, many of the works took a whimsical approach, from Dani Marti's suburban kitsch sculpture made from pool noodles to Joyce Hinterding's beautiful ink splattered diagrams for cloud engineering and, of course, Neumark and Miranda's own contribution. Consequently, and without stridency, the overarching issues operate as a kind of climate in which the works can dwell and evolve." Gail Priest, RealTme 80, 2007. The catalogue was acquired by the Guggenheim Museum, NYC

Universal Algorithm for Optimal Estimation of Quantum States from Finite Ensembles

We present a universal algorithm for the optimal quantum state estimation of an arbitrary finite dimensional system. The algorithm specifies a physically realizable positive operator valued measurement (POVM) on a finite number of identically prepared systems. We illustrate the general formalism by applying it to different scenarios of the state estimation of N independent and identically prepared two-level systems (qubits).Comment: 4 pages, RevTeX, minor modifications to the tex