▁by ▁the ▁du ality . ▁ ▁However ▁in ▁the ▁electric ▁theory ▁the ▁mes on ▁is ▁a ▁qu ark ▁bil ine ar ▁( ), ▁while ▁in ▁the ▁magnetic ▁theory ▁it ▁is ▁a ▁fundamental ▁field . ▁ ▁In ▁both ▁theories ▁the ▁b ary ons ▁are ▁constructed ▁from ▁qu arks , ▁but ▁the ▁number ▁of ▁qu arks ▁in ▁one ▁b ary on ▁is ▁the ▁rank ▁of ▁the ▁gauge ▁group , ▁which ▁diff ers ▁in ▁the ▁two ▁dual ▁theories . ▁ ▁The ▁gauge ▁symmet ries ▁of ▁the ▁theories ▁do ▁not ▁agree , ▁which ▁is ▁not ▁problem atic ▁as ▁the ▁gauge ▁symmetry ▁is ▁a ▁feature ▁of ▁the ▁form ulation ▁and ▁not ▁of ▁the ▁fundamental ▁physics . ▁ ▁The ▁global ▁symmet ries ▁relate ▁distinct ▁physical ▁configurations ▁and ▁so ▁they ▁need ▁to ▁agree ▁in ▁any ▁dual ▁description . ▁ ▁Ev idence ▁for ▁Se i berg ▁du ality ▁ ▁The ▁mod uli ▁spaces ▁of ▁the ▁dual ▁theories ▁are ▁identical . ▁ ▁The ▁global ▁symmet ries ▁agree , ▁as ▁do ▁the ▁charges ▁of ▁the ▁mes ons ▁and ▁b ary ons . ▁ ▁In ▁certain ▁cases ▁it ▁reduces ▁to ▁ordinary ▁elect romagnet ic ▁du ality . ▁ ▁It ▁may ▁be ▁embedded ▁in ▁string ▁theory ▁via ▁Han any - W itten ▁b rane ▁cart o ons ▁consisting ▁of ▁intersect ing ▁D - b ran es . ▁ ▁There ▁it ▁is ▁realized ▁as ▁the ▁motion ▁of ▁an ▁NS 5 - b rane ▁which ▁is ▁conject ured ▁to ▁preserve ▁the ▁univers ality ▁class . ▁ ▁Six ▁n ont rivial ▁anom al ies ▁may ▁be ▁computed ▁on