On the homotopy of Q (3) and Q (5) at the prime 2
M Behrens, K Ormsby - Algebraic & Geometric Topology, 2016 - msp.org
We study modular approximations Q (ℓ), ℓ= 3, 5, of the K (2)–local sphere at the prime 2 that
arise from ℓ–power degree isogenies of elliptic curves. We develop Hopf algebroid level …
arise from ℓ–power degree isogenies of elliptic curves. We develop Hopf algebroid level …
The algebraic duality resolution at p= 2
A Beaudry - Algebraic & Geometric Topology, 2016 - msp.org
The goal of this paper is to develop some of the machinery necessary for doing K (2)–local
computations in the stable homotopy category using duality resolutions at the prime p= 2 …
computations in the stable homotopy category using duality resolutions at the prime p= 2 …
On the ring of cooperations for 2‐primary connective topological modular forms
M Behrens, K Ormsby, N Stapleton… - Journal of …, 2019 - Wiley Online Library
We analyze the ring tmf∗ tmf of cooperations for the connective spectrum of topological
modular forms (at the prime 2) through a variety of perspectives:(1) the E 2‐term of the …
modular forms (at the prime 2) through a variety of perspectives:(1) the E 2‐term of the …
Congruences between modular forms given by the divided β family in homotopy theory
M Behrens - Geometry & Topology, 2009 - msp.org
We characterize the 2–line of the p–local Adams–Novikov spectral sequence in terms of
modular forms satisfying a certain explicit congruence condition for primes p≥ 5. We give a …
modular forms satisfying a certain explicit congruence condition for primes p≥ 5. We give a …
Buildings, elliptic curves, and the K (2)-local sphere
M Behrens - American journal of mathematics, 2007 - muse.jhu.edu
We investigate a dense subgroup Γ of the second Morava stabilizer group given by a certain
group of quasi-isogenies of a supersingular elliptic curve in characteristic p. The group Γ …
group of quasi-isogenies of a supersingular elliptic curve in characteristic p. The group Γ …
ˇ–family congruences and the f–invariant
-3mu--family congruences and the f-5mu--invariant Page 1 Geometry & Topology Monographs
16 (2009) 9–29 9 ˇ–family congruences and the f–invariant MARK BEHRENS GERD LAURES …
16 (2009) 9–29 9 ˇ–family congruences and the f–invariant MARK BEHRENS GERD LAURES …
Modular isogeny complexes
C Rezk - Algebraic & Geometric Topology, 2012 - msp.org
We describe a vanishing result on the cohomology of a cochain complex associated to the
moduli of chains of finite subgroup schemes on elliptic curves. These results have …
moduli of chains of finite subgroup schemes on elliptic curves. These results have …
Higher real K‐theories and topological automorphic forms
M Behrens, MJ Hopkins - Journal of Topology, 2011 - Wiley Online Library
Given a maximal finite subgroup G of the nth Morava stabilizer group at a prime p, we
address the question: is the associated higher real K‐theory EOn a summand of the K (n) …
address the question: is the associated higher real K‐theory EOn a summand of the K (n) …
Arithmetically defined dense subgroups of Morava stabilizer groups
N Naumann - Compositio Mathematica, 2008 - cambridge.org
For every prime p and integer n≥ 3 we explicitly construct an abelian variety of dimension n
such that for a suitable prime l the group of quasi-isogenies of of l-power degree is …
such that for a suitable prime l the group of quasi-isogenies of of l-power degree is …