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Despite the differences of our economic systems, models of governance, cultures, and population sizes, China and Australia share common destinies as societies with rapidly urbanising futures. This presents significant challenges for urban planning, placemaking, and the sustainability of livable, urban communities in our cities. The experimental project ‘metaPLACE’ aims to use Australian derived participatory urban media to test the effectiveness of co-designed urban media interfaces in helping government and urban planners better understand and design for rapidly urbanising cities. Using Chongqing as a case study, metaPLACE tests the theoretical assumption that participatory urban media (large and small interactive screens, installations, facades, and devices) can act as a co-designed interface between diverse community, industry, and government stakeholders. The research assesses how interactive media installations can build engagement and dialogue between citizens and other city stakeholders about the places in which they live, work, and play. Our initial findings suggest despite the current political tensions, Sino-Australian co-operation can transcend disciplinary silos, and culturally biased assumptions about design to collaboratively identify placemaking problems and co-design novel urban media concepts and solutions.

In previous work we demonstrated that the enlarged super-Poincare algebras which underlie p-brane and D-brane actions in superstring theory can be directly determined based on the integrability of supersymmetry transformations assigned to fields appearing in Wess-Zumino terms. In that work we derived p-brane superalgebras for p = 2 and 3. Here we extend our previous results and give a compact expression for superalgebras for all valid p., Comment: 26 pages, table added, typos corrected, a few remarks added for clarification

It has long been appreciated that superalgebras with bosonic and fermionic generators additional to those in the super-Poincare algebra underlie p-brane and D-brane actions in superstring theory. These algebras have been revealed via "bottom up" approaches, involving consideration of Noether charges, and by "top down" approaches, involving the construction of manifestly supersymmetry invariant Wess-Zumino actions. In this paper, we give an alternative derivation of these algebras based on integrability of supersymmetry transformations assigned to fields in order to solve a cohomology problem related to the construction of Wess-Zumino terms for p-brane and D-brane actions., 22 pages, typo corrected, reference added

We present off-shell $$ \mathcal{N}=2 $$ supergravity actions, which exhibit spontaneously broken local supersymmetry and allow for de Sitter vacua for certain values of the parameters. They are obtained by coupling the standard $$ \mathcal{N}=2 $$ supergravity-matter systems to the Goldstino superfields introduced in arXiv:1105.3001 and arXiv:1607.01277 in the rigid supersymmetric case. These $$ \mathcal{N}=2 $$ Goldstino superfields include nilpotent chiral and linear supermultiplets. We also describe a new reducible $$ \mathcal{N}=1 $$ Goldstino supermultiplet.

Insights Live screening and playfulness of the interactive space can be effective strategies for attracting the attention of passers-by and turn them into active participants. While urban screen interfaces increase participation by encouraging group interaction, privately-oriented tangible user interfaces give people a longer time to reflect upon their answers.

Could you trust someone you had never physically met to successfully collaborate with you on a design project?As online communication technologies rapidly evolve, the creative industries continue to move towards globally networked and interdisciplinary modalities of practice. These inescapable shifts in the ways designers work have challenged many long held assumptions about the nature of individual design processes.Such revolutionary changes mean that designers must increasingly master new skills to effectively communicate and collaborate in online environments with colleagues from different cultures, disciplines and locations world-wide. Since they may never meet face-to-face, the success of this new working methodology relies on high levels of trust between practitioners, both personally and professionally in order to achieve effective design outcomes.In turn the need for design educators to equip students with skills to thrive in the face of this new industrial paradigm is highlighted. Trust i...

Within the background field approach, all two-loop sunset vacuum diagrams, which occur in the Coulomb branch of N = 2 superconformal theories(including N = 4 SYM), obey the BPS condition m_3 = m_1 + m_2, where the masses are generated by the scalars belonging to a background N = 2 vector multiplet. These diagrams can be evaluated exactly, and prove to be homogeneous quadratic functions of the one-loop tadpoles J(m_1^2), J(m_2^2) and J(m_3^2), with the coefficients being rational functions of the squared masses. We demonstrate that, if one switches on the beta-deformation of the N = 4 SYM theory, the BPS condition no longer holds, and then generic two-loop sunset vacuum diagrams with three non-vanishing masses prove to be characterized by the following property: 2(m_1^2 m_2^2 +m_1^2 m_3^2 +m_2^2 m_3^2) > m_1^4 +m_2^4 +m_3^4. In the literature, there exist several techniques to compute such diagrams. For the beta-deformed N = 4 SYM theory, we carry out explicit two-loop calculations of the Kahler potential and F^4 term. Our considerations are restricted to the case of beta real., 42 pages, latex, 1 eps figure; V2: references added

This paper presents findings from a series of iterative field studies on the use of interactive, situated digital technologies deployed within a pop-up style format used for the purpose of community engagement. Based on observations, participant interviews, and a focus group with representatives from the local government authority, the contribution of this research is twofold. First, we propose five elements to guide the design of digital pop-up interventions for community engagement. Second, we demonstrate the effectiveness of combining digital interfaces and a physical pop-up within a civic space equipped with a large urban screen to engage wider cross-sections of the public. From that, we derive insights about the utilisation of this approach in attracting the attention of people who do not generally attend traditional community engagement events, and provide a more seamless consultation process by enabling citizens to submit their responses on the spot.

Large digital screens are becoming prevalent across today’s cities dispersing into everyday urban spaces such as public squares and cultural precincts. Examples, such as Federation Square, demonstrate the opportunities for using digital screens to create a sense of place and to add long-term social, cultural and economic value for citizens, who live and work in those precincts. However, the challenge of implementing digital screens in new urban developments is to ensure they respond appropriately to the physical and sociocultural environment in which they are placed. Considering the increasing rate at which digital screens are being embedded into public spaces, it is surprising that the programs running on these screens still seem to be stuck in the cinematic model. The availability of advanced networking and interaction technologies offers opportunities for information access that goes beyond free-to-air television and advertising. This chapter revisits the history and current state of digital screens in urban life and discusses a series of research studies that involve digital screens as interface between citizens and the city. Instead of focusing on technological concerns, the chapter presents a holistic analysis of these studies, with the aim to move towards a more comprehensive understanding of the sociocultural potential of this new media platform, and how the digital content is linked with the spatial quality of the physical space, as well as the place and role of digital screens within the smart city movement.

D-branes have a world-volume U(1) gauge field A whose field strength F = dA gives rise to a Born-Infeld term in the D-brane action. Supersymmetry and kappa symmetry transformations of A are traditionally inferred by the requirement that the Born-Infeld term is consistent with both supersymmetry and kappa symmetry of the D-brane action. In this paper, we show that integrability of the assigned supersymmetry transformations leads to a extension of the standard supersymmetry algebra that includes a fermionic central charge. We construct a superspace one-form on an enlarged superspace related by a coset construction to this centrally extended algebra whose supersymmetry and kappa symmetry transformations are derived, rather than inferred. It is shown that under pullback, these transformations are of the form expected for the D-brane U(1) gauge field. We relate these results to manifestly supersymmetric approaches to construction of D-brane actions., Comment: 15 pages; new section and references added

This article traces Japanese and Australian media portrayals of the cultural aspects to the bilateral relationship. The article examines popular discourse about Japan and Australia in the media of each country, demonstrating how this has reflected the evolution of the cultural relationship. In Australia, the press has swung from portraying Japan as a problematic source of income from the resources trade, through to the home of ‘cool’ technology and fashion. In Japan, discourse about Australia has ranged from images of a country populated with cute animals, to a regional partner sharing the same democratic ideals. The article draws from the personal experiences of the author who was a correspondent and journalist for Australian and Japanese news corporations during the 1980s and 1990s. The author covered the ‘koala wars’ and the frill-necked lizard boom prompted by the Mitsubishi Mirage television commercial, as well as monitoring the growth in Japanese tourism to Australia. The author also draws on data f...

A closed-form expression is obtained for a holomorphic sector of the two-loop low-energy effective action for the N = 4 super Yang–Mills theory on its Coulomb branch where the gauge group SU ( N ) is spontaneously broken to SU ( N − 1 ) × U ( 1 ) and the dynamics is described by a single Abelian N = 2 vector multiplet. In the framework of the background-field method, this holomorphic sector is singled out by computing the effective action for a background N = 2 vector multiplet satisfying a relaxed super self-duality condition. At the two-loop level, the N = 4 SYM effective action is shown to possess no F 4 term (with F the U ( 1 ) field strength), in accordance with the Dine–Seiberg non-renormalization conjecture hep-th/9705057 and its generalized form given in hep-th/0310025 . An unexpected outcome of our calculation is that no (manifestly supersymmetric invariant generating) F 6 quantum correction occurs at two loops. This is in conflict with previous results.

A closed-form expression is obtained for a holomorphic sector of the two-loop Euler-Heisenberg type effective action for N = 2 supersymmetric QED derived in hep-th/0308136. In the framework of the background-field method, this sector is singled out by computing the effective action for a background N = 2 vector multiplet satisfying a relaxed super self-duality condition. The approach advocated in this letter can be applied, in particular, to the study of the N = 4 super Yang-Mills theory on its Coulomb branch., 8 pages, latex; V2: comments, references added, typos corrected

In N =2,4 superconformal field theories in four space–time dimensions, the quantum corrections with four derivatives are believed to be severely constrained by non-renormalization theorems. The strongest of these is the conjecture formulated by Dine and Seiberg in hep-th/9705057 that such terms are generated only at one loop. In this note, using the background field formulation in N =1 superspace, we test the Dine–Seiberg proposal by comparing the two-loop F 4 quantum corrections in two different superconformal theories with the same gauge group SU ( N ): (i) N =4 SYM (i.e., N =2 SYM with a single adjoint hypermultiplet); (ii) N =2 SYM with 2 N hypermultiplets in the fundamental. According to the Dine–Seiberg conjecture, these theories should yield identical two-loop F 4 contributions from all the supergraphs involving quantum hypermultiplets, since the pure N =2 SYM and ghost sectors are identical provided the same gauge conditions are chosen. We explicitly evaluate the relevant two-loop supergraphs and observe that the F 4 corrections generated have different large N behaviour in the two theories under consideration. Our results are in conflict with the Dine–Seiberg conjecture.

We determine the one-loop deformation of the conformal symmetry of a general N}=2 superconformally invariant Yang-Mills theory. The deformation is computed for several explicit examples which have a realization as world-volume theories on a stack of D3 branes. These include (i) N=4 SYM with gauge groups SU(N), USp(2N) and SO(N); (ii) USp(2N) gauge theory with one hypermultiplet in the traceless antisymmetric representation and four hypermultiplets in the fundamental; (iii) quiver gauge theory with gauge group SU(N)xSU(N) and two hypermultiplets in the bifundamental representations (N,\bar N) and (bar N,N). The existence of quantum corrections to the conformal transformations imposes restrictions on the effective action which we study on a subset of the Coulomb branch corresponding to the separation of one brane from the stack. In the N=4 case, the one-loop corrected transformations provide a realization of the conformal algebra; this deformation is shown to be one-loop exact. For the other two models, higher-loop corrections are necessary to close the algebra. Requiring closure, we infer the two-loop conformal deformation.

The effective action in gauge theories is known to depend on a choice of gauge fixing conditions. This dependence is such that any change of gauge conditions is equivalent to a field redefinition in the effective action. In this sense, the quantum deformation of conformal symmetry in the N = 4 super Yang-Mills theory, which was computed in 't Hooft gauge in hep-th/9808039 and hep-th/0203236, is gauge dependent. The deformation is an intrinsic property of the theory in that it cannot be eliminated by a local choice of gauge (although we sketch a field redefinition induced by a nonlocal gauge which, on the Coulomb branch of the theory, converts the one-loop quantum-corrected conformal transformations to the classical ones). We explicitly compute the deformed conformal symmetry in R_\xi gauge. The conformal transformation law of the gauge field turns out to be \xi-independent. We construct the scalar field redefinition which relates the 't Hooft and R_\xi gauge results. A unique feature of 't Hooft gauge is that it makes it possible to consistently truncate the one-loop conformal deformation to the terms of first order in derivatives of the fields such that the corresponding transformations form a field realization of the conformal algebra., Comment: 14 pages, latex, no figures; references and comments added, the final version to appear in PLB

In an earlier paper (hep-th/0101127), we developed heat kernel techniques in N = 2 harmonic superspace for the calculation of the low-energy effective action of N = 4 SYM theory, which can be considered as the most symmetric N = 2 SYM theory. Here, the results are extended to generic N = 2 SYM theories. This involves a prescription for computing the variation of the hypermultiplet effective action. Integrability of this variation allows the hypermultiplet effective action to be deduced. This prescription permits a very simple superfield derivation of the perturbative holomorphic prepotential. Explicit calculations of the prepotential and the leading non-holomorphic correction are presented.

Using the N = 2 off-shell formulation in harmonic superspace for N = 4 super Yang-Mills theory, we present a representation of the one-loop effective action which is free of so-called coinciding harmonic singularities and admits a straightforward evaluation of low-energy quantum corrections in the framework of an N = 2 superfield heat kernel technique. We illustrate our approach by computing the low-energy effective action on the Coulomb branch of SU(2) N = 4 super Yang-Mills. Our work provides the first derivation of the low-energy action of N = 4 super Yang-Mills theory directly in N = 2 superspace without any reduction to N = 1 superfields and for a generic background N = 2 Yang-Mills multiplet.

Low energy effective actions are computed by integrating out degrees of freedom heavier than some energy scale of physical interest. At the one-loop level, the low energy effective action can be computed in terms of the functional trace of the heat kernel associated with the operator appearing in the part of the action quadratic in the heavy fields. Here, a technique for computing this functional trace is illustrated in the case of heavy scalar fields coupled to a Yang-Mills background. It makes use of the similarity of the functional trace of the heat kernel expressed in momentum space to a Gaussian integral. An explicit computation of the piece of the low energy effective action for the Yang-Mills fields quadratic in derivatives of the field strength is carried out, extending previously known results on the form of the long wavelength limit of the low energy effective action.

As a result of the Wess-Zumino term in its action, the eleven-dimensional supermembrane realizes the super-Poincare algebra extended by a Schwinger term containing a two-form charge. A set of “descent equations” are determined which place the relationship between the Wess-Zumino Lagrangian and the Schwinger term on a cohomological footing.

Dans les annees 1880-1890, l’utilisation de la stenographie pour publier de la facon la plus fidele les recits des conteurs professionnels connus sous le nom de rakugoka permit a ces derniers d’etre connus et apprecies d’un tres large public. C’est au cours de cette periode qu’un citoyen britannique d'origine australienne, Henry Black (1858-1923), se fit conteur professionnel et raconta des histoires se deroulant en Grande-Bretagne ou en France afin de faire comprendre a un public populaire les changements sociaux inities par le gouvernement de Meiji. Ses histoires constituaient des modeles pour aider les Japonais a entrer dans la modernite de la fin du XIXe siecle. Elles illustraient les reformes juridiques, les nouvelles relations entre les hommes et les femmes et la nouvelle urbanite. Black fut en ce sens un participant enthousiaste des debats de l’ere Meiji sur le sens de la modernite.

In four-dimensional N=1 Minkowski superspace, general nonlinear sigma models with four-dimensional target spaces may be realised in term of CCL (chiral and complex linear) dynamical variables which consist of a chiral scalar, a complex linear scalar and their conjugate superfields. Here we introduce CCL sigma models that are invariant under U(1) "duality rotations" exchanging the dynamical variables and their equations of motion. The Lagrangians of such sigma models prove to obey a partial differential equation that is analogous to the self-duality equation obeyed by U(1) duality invariant models for nonlinear electrodynamics. These sigma models are self-dual under a Legendre transformation that simultaneously dualises (i) the chiral multiplet into a complex linear one; and (ii) the complex linear multiplet into a chiral one. Any CCL sigma model possesses a dual formulation given in terms of two chiral multiplets. The U(1) duality invariance of the CCL sigma model proves to be equivalent, in the dual chiral formulation, to a manifest U(1) invariance rotating the two chiral scalars. Since the target space has a holomorphic Killing vector, the sigma model possesses a third formulation realised in terms of a chiral multiplet and a tensor multiplet. The family of U(1) duality invariant CCL sigma models includes a subset of N=2 supersymmetric theories. Their target spaces are hyper Kahler manifolds with a non-zero Killing vector field. In the case that the Killing vector field is triholomorphic, the sigma model admits a dual formulation in terms of a self-interacting off-shell N=2 tensor multiplet. We also identify a subset of CCL sigma models which are in a one-to-one correspondence with the U(1) duality invariant models for nonlinear electrodynamics. The target space isometry group for these sigma models contains a subgroup U(1) x U(1)., 22 pages; V2: typos corrected

A representation of a subgroup H of a finite-dimensional group G can be used to induce a nonlinear realization of G. If the nonlinearly realized symmetry is gauged, then the BRST charge can be related by a similarity transformation to the BRST charge for the gauged linear realization of H (plus a cohomologically trivial piece). It is shown that the relation between the two BRST charges is a reflection of the fact that they can be interpreted geometrically as expressions for the exterior derivative on G relative to two different bases, and an explicit expression for the generator of the similarity transformation is obtained. This result is applied in an infinite-dimensional setting, where it yields the similarity transformation used by Ishikawa and Kato to prove the equivalence of the Berkovits-Vafa superstring with the underlying bosonic string theory., Comment: 14 pages, LATEX document

The rapid advancement of online communication technologies is reconfiguring the creative industries through globally networked and interdisciplinary modalities of practice. These inescapable shifts are challenging most of our assumptions about the nature of creative processes. Consequently art and design educators are impelled to teach students in ways that mirror contemporary creative processes. This inevitably includes collaboration in online environments. Instigated in 2003, The Collabor8 Project (C8) responds to these conditions by challenging design students from universities and colleges in Australia and China to collaborate online. Recently, C8 has evolved to integrate blended pedagogical strategies that enable stronger collaborative relationships to develop. This chapter provides a comparative analysis of two project iterations conducted during 2008 and 2009. Using data collected through observation, interviews, questionnaires, discussions, and specific research tasks within creative briefs, it identifies, discusses, and offers insights relating to a range of issues encountered in collaborative interactions between very different groups of undergraduate and postgraduate art and design students.

The supersymmetric eigenvalue model has been proposed as the analogue for two-dimensional supergravity of the matrix model. The double-scaling limit exhibits an integrable fermionic hierarchy which is related to the Korteweg-de Vries hierarchy. In this paper, a discrete analogue of this integrable structure, related to the Toda lattice, is found in the supersymmetric eigenvalue model.

Recursion relations are established for the residues of fractional powers of a two-reduced super-KP operator making use of the Baker-Akhiezer function. These show the integrability of the two-reduced even (or bosonic) flows of the super-KP hierarchy. Similar recursion relations are also proven for the residues of operators associated with the odd (or fermionic) flows of the Mulase-Rabin super-KP hierarchy. Due to the presence of a spectral parameter and its fermionic partner in the Baker-Akhiezer function, these recursion relations should be relevant to any attempt to prove or disprove a recent proposal that the integrable hierarchy underlying two-dimensional quantum supergravity is the Mulase-Rabin super-KP hierarchy.

In gauge theories, not all rigid symmetries of the classical action can be maintained manifestly in the quantization procedure, even in the absence of anomalies. If this occurs for an anomaly-free symmetry, the effective action is invariant under a transformation that differs from its classical counterpart by quantum corrections. In this note, we set up a harmonic superspace formalism for computing quantum deformations of superconformal symmetry in the N = 4 supersymmetric Yang–Mills theory.

We examine spontaneously broken N=2 supersymmetry in four dimensions and associate a spinor superfield with each Goldstino via a finite supersymmetry transformation with parameters that are the Grassmann coordinates of N=2 superspace. Making use of a special choice of coset parametrization allows us to develop a version of nonlinearly realized N=2 supersymmetry for which the associated Goldstino superfields are defined on harmonic superspace, thereby providing a natural mechanism for construction of a Goldstino action. The corresponding superfield Lagrangian is an O(4) multiplet. This property is used to reformulate the Goldstino action in projective superspace and in conventional N=2 superspace. We show how to generate matter couplings of the Goldstinos to supersymmetric matter using the N=2 harmonic, projective and full superspaces. As a bi-product of our consideration, we also derive an N=2 chiral Goldstino action.

A new fermionic extension of the KdV hierarchy was recently found by Becker and Becker (1993) in relation to two-dimensional quantum supergravity, and it was shown that the hierarchy possesses a supersymmetry which has been exploited to prove the integrability of the hierarchy by Figueroa-O'Farrill and Stanciu (1993). Here, a larger group of fermionic symmetries of the new hierarchy is demonstrated and the bi-Hamiltonian structure is expressed in terms of odd Poisson brackets which are related to the antibracket of the Batalin-Vilkovisky formalism.

The fermionic integrations are carried out explicitly in the partition function for the supersymmetric eigenvalue model, which is a supersymmetric generalization of the eigenvalue model resulting from the Hermitian one-matrix model. The resulting expression confirms a conjecture by Becker and Becker that the free energy is at most quadratic in the fermionic couplings which appear in the potential.

The integrability of the super-KdV hierarchy suggests that it can be written in Hirota bilinear form as the group orbit equation for some infinite-dimensional Lie algebra. We show how the first few equations in the hierarchy can be written in Hirota bilinear form. We also conjecture a bilinear expression for the whole super-KdV hierarchy and check it to reasonably high orders. A by-product is an expression for the ordinary KdV hierarchy which provides an alternative to the ones obtained by Date et al. and Kac and Wakimoto.

We generalize the resolvent approach of Gelfand and Dikii to the KdV equation to study the N = 2 supersymmetric KdV equations of Laberge and Mathieu. For the associated Lax operators, we study the coincidence limits of the resolvent kernel and its derivatives, and obtain differential equations which they satisfy. These allow us to obtain recursion relations for the analogues of the Gelfand-Dikii polynomials and to obtain a proof of Hamiltonian integrability of the supersymmetric KdV equations. We are also able to write the Lax equations for the corresponding hierarchies in terms of these polynomials.

The embedding of a $p$-brane into higher dimensional spacetime breaks not only translational symmetries transverse to the worldvolume, but also Lorentz symmetries. There exist formulations for $p$-brane actions which associate Goldstone bosons with the generators of the broken Lorentz symmetries. These Goldstone bosons are unphysical, in that they can be eliminated in favour of other Goldstone bosons either via their equations of motion or via the imposition of an inverse Higgs constraint. In this paper, we examine the inter-relationship between the coset parameterization necessary to implement the inverse Higgs constraint, the equivalence of the inverse Higgs constraint to equations of motion, and the ability to find versions of the action with no explicit dependence on the unphysical Goldstone bosons. This is evidence that the unphysical Goldstone bosons are gauge degrees of freedom associated with an enlarged isotropy group. In addition to $p$-brane actions, a number of other cases, including conformally invariant dilaton actions, are shown to exhibit the same structure., Comment: 24 pages; references added