Sir Rickard Christophers

Some Examples of Rickard Complexes

After a presentation of Brou e's conjecture for principal blocks with an abelian defect group, we describe a Rickard complex for GL 2 (q) arising from thè-adic cohomology of a Deligne-Lusztig variety, in accordance with the explicit form given by Brou e to his conjecture in the case of Chevalley groups in non natural characteristic.

The host-parasite relationship in filariasis.

Election to the once of President of the Royal Society of Tropical Medicine is a greatly appreciated honour, but six months later the bill arrives, in the form of a call for a Presidential Address, and with it comes the realization that the honour bestowed carries with it certain responsibilities and obligations. To obtain inspiration I have turned, as I suppose all my predecessors have done, t...

Rickard Equivalences and Block Theory

De nition We say that a subgroup H of G controls the fusion of p subgroups of G if the following two conditions are ful lled C H contains a Sylow p subgroup Sp of G C whenever P is a subgroup of Sp and g is an element of G such that gPg Sp there exist z in the centralizer CG P of P in G and h in H such that g hz Basic example We denote by Op G the largest normal subgroup of G with order prime t...

Block Theory via Stable and Rickard Equivalences

Yes Sir, no Sir, not much difference Sir.

OBJECTIVE To assess whether making the sender's knighthood explicit in a series of letters would have any detectable effect on the response. DESIGN A random sequence was generated by flipping a coin to determine whether a letter would have 'Sir Iain Chalmers' or 'Iain Chalmers' typed under the signature. This sequence was prepared independently of the preparation of an alphabetic list of the ...