We study the homological finiteness property FPn of fibre products. A homological version of the n - (n + 1) - (n + 2) Conjecture is suggested and solved in some cases. Though the Homological 1-2-3 Conjecture is still open, we prove a homological version of the Virtual Surjection Conjecture in the case of virtual surjection on pairs.
机构:
UNIV LONDON QUEEN MARY & WESTFIELD COLL,SCH MATH SCI,LONDON E1 4NS,ENGLANDUNIV LONDON QUEEN MARY & WESTFIELD COLL,SCH MATH SCI,LONDON E1 4NS,ENGLAND