Unifying the four interactions governing the Universe, An Overview

Formerly in the Department of Chemistry, Indian Institute of Technology, Kanpur-20R 016.
Uttar Pradesh, India
Formerly in the Department of Chemistry, University of Allahabad. Allahabad-211 002.
Uttar Pradesh, India
E-mail : dr _ nigam@rediffmail.com, dr _nigam@sify .com
Manuscript received 01 July 2011, accepted 04 July 2011

The nature of the matter and/or energy present in the Universe is seen as ultimate interactions in between all fundamental particles at very high energy. The forces designated as electromagnetic, strong. weak and gravitational are known to govern these interactions. The theories called Quantum Electrodynamics and Quantum Chromodynamies respectively are known to explain the electromagnetic and strong interactions. The weak interaction, indicated solely by p-decay phenomenon shows an astonishing property of violation of parity. The gravitational interaction is an extremely weak one at microscopic level, and the least understood interaction. A close connection has however been found between weak and electromagnetic interactions leading to the belief that a close connection exists between large scale Universe and microscopic scale universe. In fact, a search for a grand unified theory is on super-symmetry theory, super-symmetry theory and M-theory proposed of late do not gin a clear picture. This article gives an overview of this and discusses the underlying principles as also future challenges in this context.