Importance of Baryon-Baryon Coupling in Hypernuclei
The $ΛN - ΣN$ coupling in $Λ$--hypernuclei and $ΛΛ- ΞN$ coupling in $ΛΛ$--hypernuclei produce novel physics not observed in the conventional, nonstrange sector. Effects of $Λ\leftrightarrow Σ$ conversion in $^3_Λ$H are reviewed. The role of $ΛN - ΣN$ coupling suppression in the $A=4,5$ $Λ$--hypernuclei due to Pauli blocking is highlighted, and the implications for the structure of $^{10}_{\;\, Λ}$B are explored. Suppression of $ΛΛ- ΞN$ conversion in $^{\;\;\, 6}_{ΛΛ}$He is hypothesized as the reason that the $< V_{ΛΛ} >$ matrix element is small. Measurement of $^{\;\;\, 4}_{ΛΛ}$H is proposed to investigate the full $ΛΛ- ΞN$ interaction. The implication for $ΛΛ$ analog states is discussed.