Johannes Nordström

E-mail:	j dot nordstrom at bath dot ac dot uk
	Public key
Phone:	01225 384479
Address:	Department of Mathematical Sciences University of Bath Claverton Down Bath BA2 7AY

I am a reader in the algebra and geometry group at the Bath maths department.

We are hosting the 2025 LMS undergraduate summer school.

Research

Journal papers

with Diarmuid Crowley and Sebastian Goette An analytic invariant of G₂-manifolds, Invent. Math. 239 (2025), 865-907 (Inv. Math., arXiv)
with Karsten Matthies and Matt Turner SU(2)² x U(1)-invariant G₂-instantons on the AC limit of the C7 family, Comm. Anal. Geom. 32 (2024), 2505-2549 (arXiv)
Extra-twisted connected sum G₂-manifolds, Ann. Glob. Anal. Geom. 64 (2023) (AGAG, arXiv)
with Lorenzo Foscolo and Mark Haskins Complete non-compact G₂-manifolds from asymptotically conical Calabi-Yau 3-folds, Duke Math. J. 170 (2021), 3323-3416 (DMJ, arXiv)
with Diarmuid Crowley Exotic G₂-manifolds, Math. Ann. 381 (2021), 29-74 (Math Ann, arXiv)
with Lorenzo Foscolo and Mark Haskins Infinitely many new families of complete cohomogeneity one G₂-manifolds:
G₂ analogues of the Taub-NUT and Eguchi-Hanson spaces, J. Eur. Math. Soc. 23 (2021), 2153-2220 (arXiv, JEMS)
with Diarmuid Crowley The rational homotopy type of (n-1)-connected manifolds of dimension up to 5n-3, J. Top. 13 (2020), 539-575 (arXiv, JTop)
with Grégoire Menet and Henrique Sá Earp Construction of G₂-instantons via twisted connected sums, Math. Res. Letters 28 (2021), 471-509 (MRL, arXiv)
with Diarmuid Crowley The classification of 2-connected 7-manifolds, Proc. London Math. Soc. 119 (2019), 1-54. (PLMS, arXiv)
with Diarmuid Crowley New invariants of G₂-structures, Geom. Topol. 19 (2015) 2949-2992 (G&T, arXiv)
with Mark Haskins and Hans-Joachim Hein Asymptotically cylindrical Calabi-Yau manifolds, J. Diff. Geom. 101 (2015) 213-265 (JDG, arXiv)
with Alessio Corti, Mark Haskins and Tommaso Pacini G₂-manifolds and associative submanifolds from semi-Fano 3-folds,
Duke Math. J. 164 (2015) 1971-2092 (DMJ, arXiv)
with Alessio Corti, Mark Haskins and Tommaso Pacini Asymptotically cylindrical Calabi-Yau 3-folds from weak Fano 3-folds,
Geom. Topol. 17 (2013) 1955-2059 (PDF, G&T, arXiv)
Ricci-flat deformations of metrics with exceptional holonomy, Bull. London Math. Soc. 45 (2013) 1004-1018 (PDF, BLMS, arXiv)
with Alexei Kovalev Asymptotically cylindrical 7-manifolds of holonomy G₂ with applications to compact irreducible G₂-manifolds,
Ann. Global Anal. Geom. 38 (2010) 221-257 (PDF © Springer, arXiv)
Deformations of glued G₂-manifolds, Comm. Anal. Geom. 17 (2009) 481-503 (PDF © International Press, arXiv)
Deformations of asymptotically cylindrical G₂-manifolds, Math. Proc. Camb. Phil. Soc. 145 (2008) 311-348 (PDF © CUP, MPCPS, arXiv)

Other

with Mark Haskins and Rowan Juneman Sp(2)-invariant expanders and shrinkers in Laplacian flow (arXiv)
with Mark Haskins Cohomogeneity-one solitons in Laplacian flow: local, smoothly-closing and steady solitons (arXiv)
with Csaba Nagy Rational homotopy and simply-connected 8-manifolds (arXiv)
with Sebastian Goette and Don Zagier Nu-invariants of extra-twisted connected sums (arXiv)
with Diarmuid Crowley and Sebastian Goette Distinguishing G₂-manifolds, Fields Institute Communications vol. 84, Springer US, 143-172 (survey, arXiv)
Thesis (PS, PDF)

My preprints on the arXiv are collected here.

Talk slides

My Bacon-Erdős number is 7.

Teaching

Weave your own catenoid from paper strips, get a helicoid free.

ah, network is slow.
things turn out blocky.
what's clogging up my bandwidth?
I will find out soon.