Multiple choice general knowledge science & technology When did Einstein postulate that light consists of localized particles called quanta 1906 1905 1904 1909 Reveal answer Fill a bubble to check yourself B Correct answer Explanation Einstein proposed the light quantum hypothesis in 1905 in his paper on the photoelectric effect, for which he later won the Nobel Prize in Physics. This was part of his 'annus mirabilis' (miracle year) where he published four groundbreaking papers.