Abstract | For various random constraint satisfaction problems there is a significant gap between the largest constraint density
for which solutions exist and the largest density for which any polynomial time algorithm is known to find
solutions. Examples of this phenomenon include random k-SAT, random graph coloring, and a number of other
random Constraint Satisfaction Problems. To understand this gap, we study the structure of the solution space of
random k-SAT (i.e., the set of all satisfying assignments viewed as a subgraph of the Hamming cube). We prove
that for densities well below the satisfiability threshold, the solution space decomposes into an exponential number
of connected components and give quantitative bounds for the diameter, volume and number. |