Fidelity metrics for virtual environment simulations based on spatial memory awareness states

This paper describes a methodology based on human judgments of memory awareness states for assessing the simulation fidelity of a virtual environment (VE) in relation to its real scene counterpart. To demonstrate the distinction between task performance-based approaches and additional human evaluation of cognitive awareness states, a photorealistic VE was created. Resulting scenes displayed on a headmounted display (HMD) with or without head tracking and desktop monitor were then compared to the real-world task situation they represented, investigating spatial memory after exposure. Participants described how they completed their spatial recollections by selecting one of four choices of awareness states after retrieval in an initial test and a retention test a week after exposure to the environment. These reflected the level of visual mental imagery involved during retrieval, the familiarity of the recollection and also included guesses, even if informed. Experimental results revealed variations in the distribution of participants’ awareness states across conditions while, in certain cases, task performance failed to reveal any. Experimental conditions that incorporated head tracking were not associated with visually induced recollections. Generally, simulation of task performance does not necessarily lead to simulation of the awareness states involved when completing a memory task. The general premise of this research focuses on how tasks are achieved, rather than only on what is achieved. The extent to which judgments of human memory recall, memory awareness states, and presence in the physical and VE are similar provides a fidelity metric of the simulation in question

Seeing is Believing : The Capacity of the Manipulated Photograph to Represent Scenes of Mythology and the Supernatural

This illustrated paper explores the capacity of the manipulated photograph to represent scenes of mythology and the supernatural. Can a photograph, which is said to be an index of the real, render a mythical realm into a believable scene? Practices such a double exposures and combination printing have historically been used to create famous faked images of the supernatural, such as the Cottingley Fairy images and Spurgen’s photograph of the Loch Ness monster. The photograph has a causal link with reality and as such a carefully manipulated image has the power to deceive or persuade the viewer. In her photography project ‘Realm’ Carolyn Lefley explores this apparent truth-telling phenomenon by constructing double exposure photographs that create a layering of realities. A familiar domestic interior and a potentially mythological landscape combine to create scenes of make-believe, which reference texts such as Alice in Wonderland and The Lion, The Witch and the Wardrobe. Down the rabbit hole, through the looking glass and into the wardrobe, all of these paths lead from the realm of the real, into the realm of myth. The kingdom of Narnia is entered through an ordinary wardrobe. The photograph of a homely interior becomes a portal into a mythical realm. The idea of creating fictional realms and in essence writing new mythology is a practice known as mythopoeia, which fascinated authors such as JRR Tolkien, CS Lewis and George MacDonald. The photographs in ‘Realm’ depict new image-worlds of myth and wonder. Post-production techniques have been utilised to achieve these images. The paper will conclude with a consideration of the next era in photography, that of computer simulated reality. Sarah Kember notes in her book Virtual Anxiety that the veracity of the photograph is not threatened by this paradigm shift, suggesting that any representation only constructs an ‘image-idea’ of reality.Non peer reviewedFinal Accepted Versio

The Aesthetics of Theory Selection and the Logics of Art

Philosophers of science discuss whether theory selection depends on aesthetic judgments or criteria, and whether these putatively aesthetic features are genuinely extra-epistemic. As examples, judgments involving criteria such as simplicity and symmetry are often cited. However, other theory selection criteria, such as fecundity, coherence, internal consistency, and fertility, more closely match those criteria used in art contexts and by scholars working in aesthetics. Paying closer attention to the way these criteria are used in art contexts allows us to understand some evaluative and developmental practices in scientific theory selection as genuinely aesthetic, enlarging the scope of the goals of science

Globalization, Re-Discovery of the Malay ‘Local,' and Popular TV Fiction through Audience Narratives

The proliferation of TV fiction can be partly explained by TV producers attuning their products to draw audience’s attention. Narratives of love dominate the plots and almost always the good is pitted against the evil, rich against the poor - ultimately the good always wins. The formula may be clichéd, but in places where news of war, terrorism, diseases, violence, and conflicts usually prevail, respite from tumultuous realities of the world can often be found in popular TV fiction. Here, we study three popular Malay TV fiction, Julia, On Dhia, and Adam & Hawa to examine how TV fiction viewers relate to them through personal narratives and focus group interviews. Through their voices, we reveal that despite TV fiction viewers’ constant preoccupation with Western-imposed globalization, the TV fiction set against the backdrop of globalization can encourage the viewers to re-route their ways to re-discover their imaginary ‘good old days’ that are often dismissed, neglected or forgotten

‘What it is Like’ Talk is not Technical Talk

‘What it is like’ talk (‘WIL-talk’) — the use of phrases such as ‘what it is like’ — is ubiquitous in discussions of phenomenal consciousness. It is used to define, make claims about, and to offer arguments concerning consciousness. But what this talk means is unclear, as is how it means what it does: how, by putting these words in this order, we communicate something about consciousness. Without a good account of WIL-talk, we cannot be sure this talk sheds light, rather than casts shadows, on our investigations of consciousness. The popular technical account of WIL-talk (see e.g. Lewis, 1995, and Kim, 1998) holds that WIL-talk involves technical terms — terms which look like everyday words but have a distinct meaning — introduced by philosophers. I argue that this account is incorrect by showing that the alleged technical terms were not introduced by philosophers, and that these terms do not have a technical meaning

Luttinger Liquid in Non-equilibrium Steady State

We propose and investigate an exactly solvable model of non-equilibrium Luttinger liquid on a star graph, modeling a multi-terminal quantum wire junction. The boundary condition at the junction is fixed by an orthogonal matrix S, which describes the splitting of the electric current among the leads. The system is driven away from equilibrium by connecting the leads to heat baths at different temperatures and chemical potentials. The associated non-equilibrium steady state depends on S and is explicitly constructed. In this context we develop a non-equilibrium bosonization procedure and compute some basic correlation functions. Luttinger liquids with general anyon statistics are considered. The relative momentum distribution away from equilibrium turns out to be the convolution of equilibrium anyon distributions at different temperatures. Both the charge and heat transport are studied. The exact current-current correlation function is derived and the zero-frequency noise power is determined.Comment: LaTex, 1+28 pages, 7 figure

Creating a ‘new space’: code-switching among British-born Greek-Cypriots in London

This paper, located in the traditions of Interactional Sociolinguistics (Gumperz 1982) and Social Constructionism (Berger and Luckmann 1966), explores code-switching and identity practices amongst British-born Greek-Cypriots. The speakers, members of a Greek-Cypriot youth organization, are fluent in English and (with varying levels of fluency) speak the Greek-Cypriot Dialect. Quantitative and qualitative analyses of recordings of natural speech during youth community meetings and a social event show how a new ‘third space’ becomes reified through code-switching practices. By skilfully manipulating languages and styles, speakers draw on Greek-Cypriot cultural resources to accomplish two inter-related things. First, by displaying knowledge of familiar Greek-Cypriot cultural frames, they establish themselves as different from mainstream British society and establish solidarity as an in-group. Secondly, by using these frames in non-serious contexts, and at times mocking cultural attitudes and stereotypes, they challenge and re-appropriate their inherited Greek-Cypriot identity, thereby constructing the identity of British-born Greek-Cypriot youth

Probability currents as principal characteristics in the statistical mechanics of non-equilibrium steady states

One of the key features of non-equilibrium steady states (NESS) is the presence of nontrivial probability currents. We propose a general classification of NESS in which these currents play a central distinguishing role. As a corollary, we specify the transformations of the dynamic transition rates which leave a given NESS invariant. The formalism is most transparent within a continuous time master equation framework since it allows for a general graph-theoretical representation of the NESS. We discuss the consequences of these transformations for entropy production, present several simple examples, and explore some generalizations, to discrete time and continuous variables.Comment: 39 pages, 5 figures. Invited article for JSTAT Special Issue on 'Principles of Dynamics of Nonequilibrium Systems', held at the Newton Institute, Cambridge, UK, in 200

Learning with Options that Terminate Off-Policy

A temporally abstract action, or an option, is specified by a policy and a termination condition: the policy guides option behavior, and the termination condition roughly determines its length. Generally, learning with longer options (like learning with multi-step returns) is known to be more efficient. However, if the option set for the task is not ideal, and cannot express the primitive optimal policy exactly, shorter options offer more flexibility and can yield a better solution. Thus, the termination condition puts learning efficiency at odds with solution quality. We propose to resolve this dilemma by decoupling the behavior and target terminations, just like it is done with policies in off-policy learning. To this end, we give a new algorithm, Q(\beta), that learns the solution with respect to any termination condition, regardless of how the options actually terminate. We derive Q(\beta) by casting learning with options into a common framework with well-studied multi-step off-policy learning. We validate our algorithm empirically, and show that it holds up to its motivating claims.Comment: AAAI 201

Dynamical age of solar wind turbulence in the outer heliosphere

In an evolving turbulent medium, a natural timescale can be defined in terms of the energy decay time. The time evolution may be complicated by other effects such as energy supply due to driving, and spatial inhomogeneity. In the solar wind the turbulence appears not to be simply engaging in free decay, but rather the energy level observed at a particular position in the heliosphere is affected by expansion, “mixing,” and driving by stream shear. Here we discuss a new approach for estimating the “age” of solar wind turbulence as a function of heliocentric distance, using the local turbulent decay rate as the natural clock, but taking into account expansion and driving effects. The simplified formalism presented here is appropriate to low cross helicity (non-Alfvénic) turbulence in the outer heliosphere especially at low helio-latitudes. We employ Voyager data to illustrate our method, which improves upon the familiar estimates in terms of local eddy turnover times