The autoscopic flying avatar: a new paradigm to study bilocated presence in mixed reality

This position paper presents the project "Becoming Avatar" deals with avatarial immersion [1] addressed through an interdisciplinary experimental approach. Its goal, at the crossroad of the creation of images and interactive technology, of virtual reality, neurophysiology and information and communication sciences, is to develop a device and a media scenario to support the hypothesis of a split state and to objectify the situation of bilocation [2]. Being present both here in front of the screen and over there, beyond the screen, which is shown by empirical studies of video games and by artists and metaverse explorers in Second Life. This type of state resonates in neurophysiology with the artificial "Out-of-Body Experiences" sensations produced with the aid of virtual reality equipment on healthy subjects. The production includes the development of a scientific experimental facility for physiological measurements and a public installation allowing someone to live a non-ordinary experience of split self. The common feature to both aspects of the project is based on the original idea of integrating video and 3D technology in order to experiment a situation of flight in mixed reality. The subject is literally invited to "become an avatar", indeed, he sees his own image, filmed from behind, inlaid into a synthetic world where he will be able to move freely and experiment different events. This autoscopic system of immersion was imagined in 2012 by E. Pereny and worked again in 2013-2014 with Pr A. Berthoz and E.A. Amato, to be developed and finalized with N. Galinotti and G. Gorisse, with Jams sessions integrating students

The autoscopic flying avatar: a new paradigm to study bilocated presence in mixed reality

This position paper presents the project "Becoming Avatar" deals with avatarial immersion [1] addressed through an interdisciplinary experimental approach. Its goal, at the crossroad of the creation of images and interactive technology, of virtual reality, neurophysiology and information and communication sciences, is to develop a device and a media scenario to support the hypothesis of a split state and to objectify the situation of bilocation [2]. Being present both here in front of the screen and over there, beyond the screen, which is shown by empirical studies of video games and by artists and metaverse explorers in Second Life. This type of state resonates in neurophysiology with the artificial "Out-of-Body Experiences" sensations produced with the aid of virtual reality equipment on healthy subjects. The production includes the development of a scientific experimental facility for physiological measurements and a public installation allowing someone to live a non-ordinary experience of split self. The common feature to both aspects of the project is based on the original idea of integrating video and 3D technology in order to experiment a situation of flight in mixed reality. The subject is literally invited to "become an avatar", indeed, he sees his own image, filmed from behind, inlaid into a synthetic world where he will be able to move freely and experiment different events. This autoscopic system of immersion was imagined in 2012 by E. Pereny and worked again in 2013-2014 with Pr A. Berthoz and E.A. Amato, to be developed and finalized with N. Galinotti and G. Gorisse, with Jams sessions integrating students

Mondes, points de vue, personnages : l'avatar comme enveloppe pilotable

Résumé du livre : Ces créatures d'images polymorphes que sont les avatars jouables nous font exister dans les mondes numériques des jeux vidéo, et même dans certains sites Web communautaires ou ludiques. Parce qu'elles nous y métamorphosent, elles apparaissent emblématiques des pratiques interactives les plus sophistiquées et troublantes. Toutefois, leurs propriétés et effets, espérés ou redoutés, restent encore à éclairer, ainsi que toutes ces interactions à distance réalisées par avatars interposés, au cœur des simulations audiovisuelles informatiques contemporaines. Ancré en sciences de l'information et de la communication, ce premier ouvrage collectif francophone sur le thème conceptualise l'avatar. Aussi, il bénéficie des apports conjugués de différentes disciplines (philosophie des techniques, psychologie, psychanalyse, sémiologie, ethnologie, sociologie, sciences de la gestion, arts). Par cette pluralité et grâce à de constants allers-retours entre théories et terrains, descriptions et analyses, hypothèses et témoignages, peuvent être articulées toutes les dimensions en jeu : technologiques, physiologiques, interpersonnelles, identitaires, intimes et/ou culturelles

revista de Ciências da Arte

O segundo volume do dossier temático Ars Ludens, procura explorar relações entre a dimensão lúdica com a tecnológica, com especial atenção aos problemas do videojogo, sobretudo nas suas tensões enquanto questão lúdica e artística. Várias questões se envolvem nessa tensão, destacando-se se o videojogo pode ser arte? E como? Ou até que ponto? Ou ainda, como se entende e recebe teórica e criticamente essa possibilidade? Temos depois as suas problemáticas curatoriais. Como se pode expor o videojogo e o que implica e significa enquanto exercício curatorial? O que é contemplar um videojogo como obra de arte ou como modo lúdico? Ou se só pode ser acção do próprio utilizador/jogador? Outra dimensão está nas alterações tecnológicas no próprio seio da ludicidade e do jogo: por exemplo, que alterações trouxeram os videojogos no campo do uso e prazer lúdico? E quais as suas implicações na nossa experiência do mundo?info:eu-repo/semantics/publishedVersio

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR, browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters. Finally we briefly discuss on the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, and touch on communication and outreach activities, the consortium organisation, and finally on the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. (abridged).Comment: 48 pages, 29 figures, Accepted for publication in Experimental Astronomy with minor editin

The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory. Athena is a versatile observatory designed to address the Hot and Energetic Universe science theme, as selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), X-IFU aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over a hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR (i.e. in the course of its preliminary definition phase, so-called B1), browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters, such as the instrument efficiency, spectral resolution, energy scale knowledge, count rate capability, non X-ray background and target of opportunity efficiency. Finally, we briefly discuss the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, touch on communication and outreach activities, the consortium organisation and the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. The X-IFU will be provided by an international consortium led by France, The Netherlands and Italy, with ESA member state contributions from Belgium, Czech Republic, Finland, Germany, Poland, Spain, Switzerland, with additional contributions from the United States and Japan.The French contribution to X-IFU is funded by CNES, CNRS and CEA. This work has been also supported by ASI (Italian Space Agency) through the Contract 2019-27-HH.0, and by the ESA (European Space Agency) Core Technology Program (CTP) Contract No. 4000114932/15/NL/BW and the AREMBES - ESA CTP No.4000116655/16/NL/BW. This publication is part of grant RTI2018-096686-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This publication is part of grant RTI2018-096686-B-C21 and PID2020-115325GB-C31 funded by MCIN/AEI/10.13039/501100011033

First measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo Binary–Black-hole Merger GW170814

International audienceWe present a multi-messenger measurement of the Hubble constant H 0 using the binary–black-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in , which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km s−1 Mpc−1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km s−1 Mpc−1, we find (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0

A gravitational-wave standard siren measurement of the Hubble constant

On 17 August 2017, the Advanced LIGO 1 and Virgo 2 detectors observed the gravitational-wave event GW170817-a strong signal from the merger of a binary neutron-star system 3 . Less than two seconds after the merger, a γ-ray burst (GRB 170817A) was detected within a region of the sky consistent with the LIGO-Virgo-derived location of the gravitational-wave source 4-6 . This sky region was subsequently observed by optical astronomy facilities 7 , resulting in the identification 8-13 of an optical transient signal within about ten arcseconds of the galaxy NGC 4993. This detection of GW170817 in both gravitational waves and electromagnetic waves represents the first 'multi-messenger' astronomical observation. Such observations enable GW170817 to be used as a 'standard siren' 14-18 (meaning that the absolute distance to the source can be determined directly from the gravitational-wave measurements) to measure the Hubble constant. This quantity represents the local expansion rate of the Universe, sets the overall scale of the Universe and is of fundamental importance to cosmology. Here we report a measurement of the Hubble constant that combines the distance to the source inferred purely from the gravitational-wave signal with the recession velocity inferred from measurements of the redshift using the electromagnetic data. In contrast to previous measurements, ours does not require the use of a cosmic 'distance ladder' 19 : the gravitational-wave analysis can be used to estimate the luminosity distance out to cosmological scales directly, without the use of intermediate astronomical distance measurements. We determine the Hubble constant to be about 70 kilometres per second per megaparsec. This value is consistent with existing measurements 20,21 , while being completely independent of them. Additional standard siren measurements from future gravitationalwave sources will enable the Hubble constant to be constrained to high precision