Search

The classical cosmological theories, based on the solution of field equations, have encountered a certain number of difficulties. To overcome these, cosmologists tend to consider new theories, especially for the early epochs of the Universe where general relativity is expected to fail.

An infrared search for the Sunyaev-Zeldovich effect toward the intergalactic ''void'' discovered by Kirshner et al. has given a null result within 1 x 10/sup -4/ K at 1 standard deviation. The result implies that the change of the Comptonization parameter toward the hole is less than 2 x 10/sup -2/. From the hypothesis that the hot gas is absent in the hole, we get an upper limit 0.5 for the normalized density of the extragalactic gas.