ARE RANDOM-WALKS RANDOM

Random walks have been created using the pseudo-random generators in d ifferent computer language compilers (BASIC, PASCAL, FORTRAN, C++) usi ng a Pentium processor. All the obtained paths have apparently a rando m behavior for short walks (similar to 2(14) steps). From long random walks (2(33) steps) different periods have been found, the shortest be ing 2(18) for PASCAL and the longest 2(31) for FORTRAN and C++, while BASIC had a 2(24) steps period. The BASIC, PASCAL and FORTRAN long wal ks had even (2 or 4) symmetries. The C++ walk systematically roams awa y from the origin. Using deviations from the mean-distance rule for ra ndom walks, [d(2)] proportional to N, a more severe criterion is found , e.g. random walks generated by a PASCAL compiler fulfills this crite rion to N < 10 000. (C) 1998 Elsevier Science B.V. All rights reserved .