▁idea ▁was ▁de vised ▁by ▁John ▁Whe eler ▁in ▁ 1 9 5 5 . ▁ ▁Background ▁ ▁With ▁an ▁incomplete ▁theory ▁of ▁quantum ▁gravity , ▁it ▁is ▁impossible ▁to ▁be ▁certain ▁what ▁spac etime ▁would ▁look ▁like ▁at ▁small ▁scales . ▁However , ▁there ▁is ▁no ▁reason ▁that ▁spac etime ▁needs ▁to ▁be ▁fund ament ally ▁smooth . ▁It ▁is ▁possible ▁that ▁instead , ▁in ▁a ▁quantum ▁theory ▁of ▁gravity , ▁spac etime ▁would ▁consist ▁of ▁many ▁small , ▁ever - ch anging ▁regions ▁in ▁which ▁space ▁and ▁time ▁are ▁not ▁definite , ▁but ▁fl uct uate ▁in ▁a ▁fo am - like ▁manner . ▁ ▁Whe eler ▁suggested ▁that ▁the ▁He isen berg ▁uncertainty ▁principle ▁might ▁imply ▁that ▁over ▁sufficiently ▁small ▁distances ▁and ▁sufficiently ▁brief ▁intervals ▁of ▁time , ▁the ▁" very ▁geometry ▁of ▁spac etime ▁fl uct u ates ". ▁These ▁fl uct u ations ▁could ▁be ▁large ▁enough ▁to ▁cause ▁significant ▁depart ures ▁from ▁the ▁smooth ▁spac etime ▁seen ▁at ▁macro scop ic ▁scales , ▁giving ▁spac etime ▁a ▁" fo amy " ▁character . ▁ ▁Ex perimental ▁results ▁▁ ▁In ▁ 2 0 0 9 ▁the ▁two ▁M AG IC ▁( M aj or ▁At mos pher ic ▁G amma - ray ▁Im aging ▁Ch eren kov ) ▁teles cop es ▁detected ▁that ▁among ▁g amma - ray ▁phot ons ▁arriv ing ▁from ▁the ▁bla zar ▁Mark arian ▁ 5 0 1 , ▁some ▁phot ons ▁at ▁different ▁energy ▁levels ▁arrived ▁at ▁different ▁times , ▁suggesting ▁that ▁some