Dark Matter, Gravity Waves, Higgs Bosons and other Elusive Entities

The twentieth century has thrown up exotic concepts -- dark matter, gravity waves, Higgs Bosons, Magnetic Monopoles and so on. The sad truth is that even after several decades, these remain elusive to observation and experiment. Some are now questioning these conjectures. Their verification has become a matter more of hope than conviction. We will examine some alternatives in the light of the above pointing out that, on the other hand, an extra neutrino, recently predicted by the author may have just been discovered.