Einstein Has Left The Building
The age of Einstein is closed forever, and it is unlikely that anyone like him will ever return. The endeavor of physics is not what it used to be a century ago. The advent of Quantum Mechanics, Relativity, Electromagnetism and many other sub categories has transformed a modestly complex study into a mind bending sophisticated puzzle of cosmic proportion. The age of the Universalists, such as Einstein are nearly extinct. Today it is exceedingly difficult to study any more than one or two fields in detail, given the high specialization needed for competence in theory or experiment.
Despite the promises of many brave or foolish researchers, Superstring remains light-years away from solving or testing any of the outstanding unsolved physics mysteries. It remains years away from even an elementary test of one of its basic premises. Assuming that it can be accomplished after nearly forty years of study.
If anything deters the next great physicist, it will be the bureaucracy of the scientific community itself. The past decades saw unbounded freedom for new and uninitiated theories and conjectures to be published and examined. In this current decade it is virtually impossible for a scientist to get a paper published and read without a PhD and University job. This is not to say that another Einstein could come along someday, but it is not likely.
The above picture is a magnet floating above a superconductor in demonstration of the Meissner effect.