Abstract

The current theoretical understanding of disoriented chiral condensate is briefly reviewed. I discuss the basic idea, the formation mechanism and experimental signatures of DCC in high energy collisions. The spontaneous symmetry-breaking mechanism plays a very important role in high energy physics. It is known that there are at least two occurrences of such phenomenon at work in the standard model: the electroweak symmetry-breaking and the chiral symmetry-breaking, in which the observed asymmetries are attributed entirely to the vacuum states of our universe. But how do we test this idea directly? Is there any way that we can create a suitable condition under which the vacuum state is disturbed for a small region of space-time so that we may be able to observe some quite different excitations and domain structures in the vacuum? Let us examine the possibility for the chiral symmetry in strong interactions. Suppose a very high energy proton-proton or nucleus-nucleus collision in cosmic rays or in Tevatron or RHIC collider. Occasionally, the collision creates a large number