One of the most interesting predictions resulting from quant um physics\, is the violation of classical symmetries\, collectively refer red to as anomalies. A remarkable class of anomalies occurs when the conti nuous scale symmetry of a scale free quantum system is broken into a discr ete scale symmetry for a critical value of a control parameter. This is an example of a (zero temperature) quantum phase transition. Such an anomaly takes place for the quantum inverse square potential known to describe ’E fimov physics’. Broken continuous scale symmetry into discrete scale symme try also appears for a charged and massless Dirac fermion in an attractive 1/r Coulomb potential. The purpose of this talk is to demonstrate the uni versality of this quantum phase transition and to present convincing exper imental evidence of its existence for a charged and massless fermion in an attractive Coulomb potential as realised in graphene.

DTSTART;TZID=America/New_York:20180228T133000 DTEND;TZID=America/New_York:20180228T143000 SUMMARY:Omrie Ovdat\, Technion University: Observing a Scale Anomaly and A Universal Quantum Phase Transition in Graphene URL:http://mini.physics.sunysb.edu/~marivi/solidstate/ai1ec_event/omrie-ovd at-technion-university-observing-a-scale-anomaly-and-a-universal-quantum-p hase-transition-in-graphene/?instance_id= END:VEVENT END:VCALENDAR