In 1966 Greisen and the team of Zatsepin and Kuzmin independently computed a limit of 5 * 10^19 eV for the energy of extragalactic cosmic rays detected on planet Earth, provided that the cosmic rays travel over 50 megaparsecs from their place of origin. However, there have been reports of the detection of cosmic rays with energies above the GZK limit. What might explain the GZK paradox? Presumably, string theorists hope that the answer might be string theory, provided that the GZK paradox is a true phenomenon. According to Witten, the three most important predictions of string theory are gravity, gauge/gravity duality, and supersymmetry. Of the three preceding predictions, supersymmetry might be the best bet for explaining the GZK paradox. This communication argues that supersymmetry with the infinite nature hypothesis is unlikely to explain the GZK paradox, while supersymmetry with the finite nature hypothesis might explain the GZK paradox within the context of ‘t Hooft’s work on the cellular automaton interpretation of quantum theory. The Milgrom Denial Hypothesis states that the main problem with string theory is that string theorists fail to realize that Milgrom is the Kepler of contemporary cosmology. The Fernández-Rañada-Milgrom effect is that the -1/2 in the standard form of Einstein’s field equations should be replaced by -1/2 + dark-compensation-constant. An argument is presented for the hypothesis that ‘t Hooft is correct about the foundations of quantum theory if and only if the Fernández-Rañada-Milgrom effect is empirically valid. If this argument is valid, then there is a decisive test for ‘t Hooft’s ideas.