Is it permissible to connect the hair of the two eyebrows? Thank you.

There is no difference in the prohibited joining of hair, whether it is for the head, eyebrows, or eyelashes, because the Prophet, peace and blessings be upon him, cursed the one who joins hair (al-wasilah) and the one for whom it is joined (al-mawsulah), and this includes all of them. The ruling is based on the generality of the wording, not the specificity of the cause.