SOME NONEXISTENCE RESULTS ON STRONG EXTERNAL DIFFERENCE FAMILIES

Abstract

Strong external difference family (SEDF) is a combinatorial configuration proposed by Paterson and Stinson in 2016. In this thesis, we derive some properties and restrictions for SEDFs with m>2 in abelian groups by using character theory. These are then used to prove several nonexistence results for nontrivial SEDFs with m>2 in abelian groups, especially when (i) v is a product of at most three primes; or (ii) λ is a product of at most two primes (under some additional conditions).