By Robert H. Sanders
Such a lot astronomers and physicists now think that the problem content material of the Universe is ruled by way of darkish subject: hypothetical debris which have interaction with general topic basically during the strength of gravity. although invisible to present direct detection tools, darkish subject can clarify a number of astronomical observations. This ebook describes how this thought has built during the last seventy five years, and why it truly is now a important function of extragalactic astronomy and cosmology. present makes an attempt to at once become aware of darkish topic in the neighborhood are mentioned, including the results for particle physics. the writer reviews at the sociology of those advancements, demonstrating how and why scientists paintings and have interaction. converted Newtonian Dynamics (MOND), the major replacement to this conception, can be offered. This interesting evaluate will curiosity cosmologists, astronomers and particle physicists. arithmetic is stored to a minimal, so the ebook could be understood via non-specialists.