is . ▁He ▁made ▁his ▁Ligue ▁ 2 ▁debut ▁at ▁ 3 0 ▁July ▁ 2 0 1 2 ▁against ▁AS ▁Mon aco ▁replacing ▁Billy ▁K et ke oph om phone ▁at ▁half - time ▁in ▁a ▁ 4 – 0 ▁away ▁loss . ▁ ▁In ▁July ▁ 2 0 1 5 , ▁Ch aval er in ▁joined ▁newly ▁promoted ▁team ▁Red ▁Star . ▁ ▁Ch aval er in ▁helped ▁St ade ▁de ▁Re ims ▁win ▁the ▁ 2 0 1 7 – 1 8 ▁Ligue ▁ 2 , ▁helping ▁promote ▁them ▁to ▁the ▁Ligue ▁ 1 ▁for ▁the ▁ 2 0 1 8 – 1 9 ▁season . ▁ ▁Career ▁statistics ▁ ▁References ▁ ▁External ▁links ▁ ▁X avier ▁Ch aval er in ▁foot - n ational . com ▁Profile ▁ ▁Category : 1 9 9 1 ▁birth s ▁Category : L iving ▁people ▁Category : Associ ation ▁football ▁mid field ers ▁Category : F rench ▁football ers ▁Category : T ours ▁FC ▁players ▁Category : Red ▁Star ▁F . C . ▁players ▁Category : St ade ▁de ▁Re ims ▁players ▁Category : L igue ▁ 1 ▁players ▁Category : L igue ▁ 2 ▁players <0x0A> </s> ▁In ▁theoretical ▁physics , ▁the ▁Jordan ▁map , ▁often ▁also ▁called ▁the ▁Jordan – Sch w inger ▁map ▁is ▁a ▁map ▁from ▁matrices ▁ ▁to ▁bil ine ar ▁expressions ▁of ▁quantum ▁oscill ators ▁which ▁exped ites ▁computation ▁of ▁ ▁representations ▁of ▁Lie ▁Al gebras ▁occurr ing ▁in ▁physics . ▁ ▁It ▁was ▁introduced ▁by ▁P