What Is... a Rip Matrix?
نویسنده
چکیده
RIP matrices– shorthand for matrices which satisfy the restricted isometry property– appeared as a byproduct of Compressed Sensing; a method discovered by D. Donoho, E. Candès and T. Tao in 2004 with several applications in computer science. Besides their real world application, RIP matrices are interesting mathematical objects because, on the one hand, a random matrix has a negligible probability of NOT satisfying the RIP, but on the other hand, deterministic constructions of RIP matrices are hard to find. The best known explicit construction, due to J. Bourgain, S. Dilworth, K. Ford, S. Konyagin and D. Kutzarova, is still very far from the best random constructions.
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