Ultra high energy cosmic rays above 1011 GeV: Hints to new physics beyond Standard ModelPIJUSHPANI BHATTACHARJEE Indian Institute of Astrophysics, Koramangala, Bangalore 560 034, India Abstract. The observed cosmic ray events above 1011 GeV are difficult to explain within the context of known physics of propagation of known particles in the Universe and within the standard acceleration mechanisms that are likely to operate in powerful astrophysical objects. Several ideas of possible new physics beyond the Standard Model have been suggested in order to explain these events. The major suggestions are summarized here. Keywords. Ultra high energy cosmic rays; physics beyond standard model. Pacs No. 98.70.Sa; 98.70.Vc; 95.30.Cq |