Publications

Publications of Stephan Klaus

Refereed Publications

see also zbMATH and Mathematical Reviews:

https://zbmath.org/authors/?q=Klaus%2C+Stephan

https://mathscinet-1ams-1org-1h49r6juh0000.mfo.hh-han.com/mathscinet/author?authorId=607300

21. Cutting, gluing, squeezing, and twisting: visual design of real algebraic surfaces
Klaus, Stephan
In: Sriraman, B. (eds) Handbook of the Mathematics of the Arts and Sciences
Springer (2021), 863–877.

20. Pseudo-angle systems and the simplicial Gauss-Bonnet-Chern theorem
Klaus, Stephan
In: Dearricott, Owen (ed.) et al., Differential geometry in the large.
Proceedings of the Australian-German workshop on differential geometry in the large, Creswick, Australia, February 4–15, 2019.
London Math. Soc. Lecture Note Ser., 463
Cambridge University Press, Cambridge, 2021, 311–325.

19. On the moduli space of equilateral plane pentagons
Klaus, Stephan; Kojima, Sadayoshi
Beitr. Algebra Geom. 60 (2019), no. 3, 487–497.

18. On different notions of higher curvature
Klaus, Stephan
An. Ştiinţ. Univ. Al. I. Cuza Iaşi. Mat. (N.S.) 64 (2018), no. 2, 327–341.

17. Nonconnected moduli spaces of nonnegative sectional curvature metrics on simply connected manifolds
Dessai, Anand; Klaus, Stephan; Tuschmann, Wilderich
Bull. Lond. Math. Soc. 50 (2018), no. 1, 96–107.

16. Fourier braids
Klaus, Stephan
In: Lambropoulou, Sofia (ed.) et al., Algebraic modeling of topological and computational structures and applications,
THALES, Athens, Greece, July 1–3, 2015.
Springer Proc. Math. Stat., 219
Springer (2017), 283–296.

15. Möbius strips, knots, pentagons, polyhedra, and the SURFER software
Klaus, Stephan
In: Decker, Wolfram (ed.) et al., Singularities and computer algebra.
Festschrift for Gert-Martin Greuel on the occasion of his 70th birthday.
Based on the conference, Lambrecht (Pfalz), Germany, June 2015.
Springer (2017), 161–172.

14. On combinatorial Gauss-Bonnet theorem for general Euclidean simplicial complexes
Klaus, Stephan
Front. Math. China 11 (2016), no. 5, 1345–1362.

13. On the positivity of the Ricci curvature, of the sectional curvature and of the curvature operator
Klaus, Stephan
An. Ştiinţ. Univ. Al. I. Cuza Iaşi. Mat. (N.S.) 60 (2014), no. 1, 157–168.

12. Reflection simplicial maps and group cohomology
Klaus, Stephan
Note Mat. 26 (2006), no. 1, 1–19.

11. A quick proof of the rational Hurewicz theorem and a computation of the rational homotopy groups of spheres
Klaus, Stephan; Kreck, Matthias
Math. Proc. Cambridge Philos. Soc. 136 (2004), no. 3, 617–623.

10. H-space structures and Postnikov approximations
Klaus, Stephan
Math. Proc. Cambridge Philos. Soc. 135 (2003), no. 1, 133–135.

09. Cochain operations and subspace arrangements
Klaus, Stephan
Port. Math. (N.S.) 60 (2003), no. 1, 71–98.

08. H-spaces with cyclic symmetry
Klaus, Stephan
Topology Appl. 124 (2002), no. 1, 1–8.

07. A generalization of the non-triviality theorem of Serre
Klaus, Stephan
Proc. Amer. Math. Soc. 130 (2002), no. 5, 1249–1256.

06. Cochain operations and higher cohomology operations
Klaus, Stephan
Cahiers Topologie Géom. Différentielle Catég. 42 (2001), no. 4, 261–284.

05. Towers and pyramids. I
Klaus, Stephan
Forum Math. 13 (2001), no. 5, 663–683.

04. On simplicial loops and H-spaces
Klaus, Stephan
Topology Appl. 112 (2001), no. 3, 337–348.

03. On the homotopy relation and self equivalences
Klaus, Stephan
Results Math. 38 (2000), no. 3-4, 261–269.

02. The Ochanine k-invariant is a Brown-Kervaire invariant
Klaus, Stephan
Topology 36 (1997), no. 1, 257–270.

01. Topological classification of 4-dimensional complete intersections
Fang, Fuquan; Klaus, Stephan
Manuscripta Math. 90 (1996), no. 2, 139–147.

Further publications

12. Solid N-twisted Mobius strips as real algebraic surfaces
Klaus, Stephan
CIM bulletin 41 (2019)
Departamento di Matematica, Universidade de Coimbra, Coimbra, pp 41–46

11. Katzengold: pyrite, plato, and a polynomial
Klaus, Stephan; Violet, Bianca
Text on Imaginary Open Mathematics (2015), 5 pages
https://imaginary.org/background-material/katzengold-pyrite-plato-and-a-polynomial

10. On algebraic, PL and Fourier degrees of knots and braids
Klaus, Stephan
Extended abstract of talk at Oberwolfach Workshop "Algebraic Structures in Low-Dimensional Topology" <1422a> (2014)
Oberwolfach Reports OWR 11.2, report 2014-26, p.32-36

09. Knot galery
Knots of Stephan Klaus (2012)
Imaginary Open Mathematics
https://imaginary.org/gallery/stephan-klaus-knots

08. The solid trefoil knot as an algebraic surface
Klaus, Stephan
featured article in CIM bulletin 28 (2010)
Departamento di Matematica, Universidade de Coimbra, Coimbra, pp 2–4

07. Solid Möbius strips as algebraic surfaces
Klaus, Stephan
Text on Imaginary Open Mathematics (2009), 10 pages
https://imaginary.org/background-material/solid-mobius-strips-as-algebraic-surfaces

06. A category of higher cohomology operations and finite spectra
Klaus, Stephan
Preprint (2000), 16 pages
(See my research gate webpage. This paper was part of my Habilitationsschrift 2000 which consisted of 4 papers. The 3 others are the refereed publications 05, 06 and 09 above. The referee noticed that my "category" B of higher cohomology operations defined in the paper is not a category on the nose as stable homotopy fibres are not functorial. Nevertheless (as the referee also remarked), the definition can be modified and B can be defined as a category using a suitable model for the stable category, e.g. stable simplicial sets in the sense of Kan. I have not corrected this minor technical problem as my research interests have changed into other directions.)

05. On simplicial loops and H-spaces
Klaus, Stephan
in: Bielefeld-Osnabrück-Workshop on Operads
Osnabrück 15.-19.06.1998, Bielefeld SFB 343 Preprint (1998), p.56-60
(full text is available at my research gate webpage)

04. The Ochanine k-Invariant is a Brown-Kervaire Invariant
Klaus, Stephan
Abstract of talk at Oberwolfach Workshop "Topologie" <9536> (1995),
Oberwolfach Tagungsbericht 39/1995, p.13-14

03. Brown-Kervaire Invariants
Klaus, Stephan
Thesis, Mainz University (1995), Shaker, 125 pages
(full text of preprint version is available at my research gate webpage)

02. The refined elliptic genus of Ochanine
Klaus, Stephan
Abstract of talk at Oberwolfach Arbeitsgemeinschaft "Elliptic Genera" <9141> (1991),
Oberwolfach Tagungsbericht 44/1991, p.12

01. Einfach-zusammenhängende kompakte homogene Räume bis zur Dimension 9
Klaus, Stephan
Diploma Thesis, Mainz University (1988), 98 pages
(full text is available at my research gate webpage)

Mathematical short movies

03. Algebraic Vibrations
Klaus, Stephan; Violet, Bianca
Movie on Imaginary Open Mathematics (2016)
https://imaginary.org/film/algebraic-vibrations

02. Katzengold
Klaus, Stephan; Violet, Bianca
Movie on Imaginary Open Mathematics (2015)
https://imaginary.org/film/katzengold

01. LPDJLQH D VHFUHW
Movie of CIM and MFO (2010)
Conception: Victor Fernandes, Stephan Klaus, Armindo Moreira and José Francisco Rodrigues
Surfer Movie Sequences: Andreas Matt and Bianca Violet
Movie on Imaginary Open Mathematics
https://imaginary.org/film/lpdjlqh-d-vhfuhw