Cattuto, C.Marconi, U.M.B.Nori, F.Soto, R.Brito López, Ricardo2023-06-202023-06-202006-05-050031-900710.1103/PhysRevLett.96.178001https://hdl.handle.net/20.500.14352/50638© American Physical Society. We acknowledge partial support from RIKEN. C. C. and F. N. acknowledge JSPS, NSA, and ARDA under AFOSR Contract No. F49620-02-1-0334 and by NSF Grant No. EIA-0130383. R. B. is supported by Projects No. FIS04-271 (Spain) and No. UCM PR27/05-13923-BSCH. U. M. B. M. is financed by Grant Cofin-Miur 2005, No. 2005027808. R. S. is partly financed by Fondecyt (Grant No. 1030993), Fondap (No. 11980002) and Universidad Complutense (Profesores Visitantes).We numerically investigate the behavior of driven noncohesive granular media and find that two fixed large intruder particles, immersed in a sea of small particles, experience, in addition to a short-range depletion force, a long-range repulsive force. The observed long-range interaction is fluctuation-induced and we propose a mechanism similar to the Casimir effect that generates it: The hydrodynamic fluctuations are geometrically confined between the intruders, producing an unbalanced renormalized pressure. An estimation based on computing the possible Fourier modes explains the repulsive force and is in qualitative agreement with the simulations.engjournal articlehttp://prl.aps.org/pdf/PRL/v96/i17/e178001 http://www.dfi.uchile.cl/~granular06/PPT_PAPERS/PhysRevLett_96_178001.pdfhttp://prl.aps.org/open access536Termodinámica2213 Termodinámica