%0 Report %T Science cases for a visible interferometer %+ Joseph Louis LAGRANGE (LAGRANGE) %+ Centre de Recherche Astrophysique de Lyon (CRAL) %+ Institut de Planétologie et d'Astrophysique de Grenoble (IPAG) %+ Astrophysique Stellaire %+ Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA) %+ Instituut voor Sterrenkunde [Leuven] %+ Research School of Astronomy and Astrophysics [Canberra] (RSAA) %+ Max-Planck-Institut für Radioastronomie (MPIFR) %+ Laboratoire Univers et Particules de Montpellier (LUPM) %+ INAF - Osservatorio Astrofisico di Arcetri (OAA) %+ Institut für Astronomie, Universität Wien (IFA) %+ Observatoire de Paris - Site de Meudon (OBSPM) %+ Centre d'Economie de l'Université Paris Nord (ancienne affiliation) (CEPN) %+ Laboratoire de Biotechnologie et Chimie Marines (LBCM) %+ Institut d'Astrophysique de Paris (IAP) %A Stee, Philippe %A Allard, France %A Benisty, Myriam %A Bigot, Lionel %A Blind, Nicolas %A Boffin, Henri %A Fernandes, Marcelo Borges %A Carciofi, Alex %A Chiavassa, Andrea %A Creevey, Orlagh %A Cruzalèbes, Pierre %A de Wit, Willem-Jan %A de Souza, Armando Domiciano %A Elvis, Martin %A Fabas, Nicolas %A Faes, Daniel %A Gallenne, Alexandre %A Pena, Carlos Guerrero %A Hillen, Michel %A Hoenig, Sebastian %A Ireland, Michael %A Kervella, Pierre %A Kishimoto, Makoto %A Kostogryz, Nadia %A Kraus, Stefan %A Labeyrie, Antoine %A Bouquin, Jean-Baptiste Le %A Lèbre, Agnès %A Ligi, Roxanne %A Marconi, Alessandro %A Marsh, Thomas %A Meilland, Anthony %A Millour, Florentin %A Monnier, John %A Mourard, Denis %A Nardetto, Nicolas %A Ohnaka, Keiichi %A Paladini, Claudia %A Perraut, Karine %A Perrin, Guy %A Petit, Pascal %A Petrov, Romain, G. %A Rakshit, Suvendu %A Schaefer, Gail %A Schneider, Jean %A Shulyak, Denis %A Simon, Michal %A Soulez, Ferréol %A Steeghs, Danny %A Tallon-Bosc, Isabelle %A Tallon, Michel %A Brummelaar, Theo Ten %A Thiébaut, Éric %A Thévenin, Frédéric %A van Winckel, Hans %A Wittkowski, Markus %A Zorec, Juan %Z White Paper prospective. This book is dedicated to the memory of our colleague Olivier Chesneau who passed away at the age of 41. v2 includes some corrections to text %I Observatoire de la Côte d'Azur %8 2017-03-08 %D 2017 %Z 1703.02395 %Z Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR] %Z Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]Reports %X High spatial resolution is the key for the understanding various astrophysical phenomena. But even with the future E-ELT, single dish instruments are limited to a spatial resolution of about 4 mas in the visible. For the closest objects within our Galaxy most of the stellar photosphere remains smaller than 1 mas. With the success of long baseline interferometry these limitations were soom overcome. Today low and high resolution interferometric instruments on the VLTI and CHARA offer an immense range of astrophysical studies. Combining more telescopes and moving to visible wavelengths broadens the science cases even more. With the idea of developing strong science cases for a future visible interferometer, we organized a science group around the following topics: pre-main sequence and main sequence stars, fundamental parameters, asteroseismology and classical pulsating stars, evolved stars, massive stars, active galactic nuclei (AGNs) and imaging techniques. A meeting was organized on the 15th and 16th of January, 2015 in Nice with the support of the Action Specific in Haute Resolution Angulaire (ASHRA), the Programme National en Physique Stellaire (PNPS), the Lagrange Laboratory and the Observatoire de la Cote d'Azur, in order to present these cases and to discuss them further for future visible interferometers. This White Paper presents the outcome of the exchanges. This book is dedicated to the memory of our colleague Olivier Chesneau who passed away at the age of 41. %G English %L hal-01630213 %U https://hal.science/hal-01630213 %~ IN2P3 %~ ENS-LYON %~ OBSPM %~ INSU %~ UNICE %~ UNIV-BREST %~ UNIV-PARIS7 %~ UNIV-SAVOIE %~ UNIV-PARIS13 %~ UPMC %~ UGA %~ CNRS %~ UNIV-LYON1 %~ UNIV-MONTP2 %~ UNIV-UBS %~ INPG %~ IRSTEA %~ CNES %~ OSUG %~ LESIA %~ IUEM %~ OCA %~ LORIA2 %~ LUPM %~ THESES_IUEM %~ CRAL %~ LAGRANGE %~ UBS %~ IAP %~ IPAG %~ CEPN %~ UBSHAL2 %~ LARA %~ PSL %~ USPC %~ AGREENIUM %~ LBCM %~ UPMC_POLE_2 %~ MIPS %~ UNIV-MONTPELLIER %~ CMM %~ UNIV-COTEDAZUR %~ SORBONNE-UNIVERSITE %~ SU-SCIENCES %~ CONDORCET3 %~ CAMPUS-CONDORCET %~ UDL %~ UNIV-LYON %~ INRAE %~ SORBONNE-PARIS-NORD %~ UNIV-PARIS %~ UP-SCIENCES %~ TEST-HALCNRS %~ OBSPM-PSL %~ UGA-COMUE %~ USMB-COMUE %~ SU-TI %~ ALLIANCE-SU %~ UM-2015-2021 %~ ACT-R