We describe a new, non-parametric, method for reconstructing lensing mass distributions in multiple-image systems, and apply it to PG1115+080, for which time delays have recently been measured. It turns out that the image positions and the ratio of time delays between different pairs of images constrain the mass distribution in a linear fashion. Since observational errors on image positions and...

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RESUMO 1Full Professor, School of Dentistry, Pontifical Catholic University of Paraná, Curitiba,Brazil. 2Doctor Professor, Endodontics, Department of Operative Dentistry, Bauru Dental School, University of São Paulo. 3Full Professor, School of Dentistry, Pontifical Catholic University of Paraná, Curitiba, Brazil. Corresponding address: Vânia Portela Ditzel Westphalen Rua Pasteur, 486, ap 401 Cu...

K. G. Arun,* Bala R. Iyer, B. S. Sathyaprakash, Siddhartha Sinha,3,5,x and Chris Van Den Broeck4,k LAL, Université Paris-Sud, IN2P3/CNRS, Orsay, France GReCO, Institut d’Astrophysique de Paris–C.N.R.S., Paris, France Raman Research Institute, Bangalore, 560 080, India School of Physics and Astronomy, Cardiff University, 5, The Parade, Cardiff, United Kingdom, CF24 3YB Department of Physics, Ind...