A couple of questions about so-called quantum foam A recent article (2013) stated that there was no delay of the sort that quantum foam would imply of photons coming from far galaxies: http://www.huffingtonpost.com/2013/01/10/quantum-foam-einstein-smooth-space-time_n_2449734.html (which includes the unfortunate typo of "proton" for "photon".) This appears to contradict earlier findings (2007), which did find a delay: http://www.news.ucdavis.edu/search/news_detail.lasso?id=8364. So, first question: were the 2007 results faulty? Second question: Given the fact that the Heisenberg Uncertainty Relation is not to be faulted, where could the faulty link be between the HUP and the existence of the quantum foam? Virtual particle pairs seem to be pretty solidly entrenched in the theory, so how could a quantum foam not exist (which, according to the article, it probably does not)? Finally, in that more recent article, sources were not given. Does anyone have a link to a more detailed (or even the original, if it is freely accessible on-line) paper on this? Thanks.