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تسجيل مستخدم جديدThe Dark Matter Enigma
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In this pedestrian approach I give my personal point of view on the various problems posed by dark matter in the universe. After a brief historical overview I discuss the various solutions stemming from high energy particle physics, and the current status of experimental research on candidate particles (WIMPS). In the absence of direct evidence, the theories can still be evaluated by comparing their implications for the formation of galaxies, clusters and superclusters of galaxies against astronomical observations. I conclude briefly with the attempts to circumvent the dark matter problem by modifying the laws of gravity.
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The LUX experimental group has just announced the most stringent upper limits so far obtained on the cross section of WIMP-nucleon elastic scattering [1]. This result is a factor of two to five below the previous best upper limit [2] and effectively
rules out earlier suggestions of low mass WIMP detection signals. The experimental expertise exhibited by this group is extremely impressive, but the fact of continued negative results raises the more basic question of whether or not this is the right approach to solving the dark matter problem. Here I comment upon this question, using as a basis the final chapter of my book on dark matter [3], somewhat revised and extended. I muse on dark matter and its alternative, modified Newtonian dynamics, or MOND.
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