We consider various models of polymer conformations using paths of Gau
ssian processes such as Brownian motion. In each case, the calculation
of the law of the moment of inertia of a random polymer structure (wh
ich is equivalent to the calculation of the partition function) is red
uced to the problem of finding the law of a certain quadratic function
al of a Gaussian process. We present a new method for computing the La
place transforms of these quadratic functionals which exploit their sp
ecial form via the Ray-Knight Theorem and which does not involve the c
lassical method of eigenvalue expansions. We apply the method to sever
al simple examples, then show how the same techniques can be applied t
o more complicated cases with the aid of a little excursion theory.