About me:
I am an assistant professor in the Geometry, groups and dynamics group at ETH Zurich with a research focus on lowdimensional topology.
Previously, I was a postdoctoral fellow at the Max Plack Institute for Mathematics in Bonn,
and before that I was at Boston College.
My PhD thesis
was advised by Sebastian Baader at the University of Bern.
For more, consult my CV or contact me directly.
How to find or contact me:
Office: HG J 59
Address: ETH Zurich,
Department of Mathematics, Raemistrasse 101, 8092 Zurich, Switzerland
email: peter.feller(you know the symbol)math.ethz.ch
Other lowdimensional topologists at ETHZ:
Dr. Matthias Nagel.
Dr. Patrick Orson.
Paula Truöl,
who I advise for her PhDstudies at the Zürich Graduate School in Mathematics.
ETHZ Geometry Seminar:
Do you like Geometry and Topology?
Check out ETHZ's Geometry Seminar.
Research Interests:
Within Geometry and Topology I am drawn to lowdimensional topology—the study of geometric objects of dimension four or less.
Onedimensional objects that lie (in a potentially knotted way) in threedimensional space—known as knots—fascinate me because their study relates to many other fields of mathematics.
Often
knot theory provides an approach toward visualizing more complicated objects.
In my knot theory research I am in particular concerned with knot concordance. Terms such as algebraic knots and links, notions of positivity for links, and the slice genus often appear in my work. I think the notion of concordance for knots provide a great point of view to understand the differences between smooth and topological 4manifolds. I also think that knots and links provided a great point of view to study 3manifolds. However, currently I am focused on studying 3manifolds via the mapping class group (buzzword: Heegaard splittings) and the curve complexe of surfaces.
I am also interested in complex plane curve singularities and their deformations and hope to understand them using positive braids and tools from HeegaardFloer theory.
And I wonder in how many ways complex algebraic varieties embed in affine space and affine algebraic groups.
Maybe there are as many algebraic embeddings of the complex numbers in threedimensional affine space as there are knots in the threesphere,
probably (k)not; however, we should find out!
You can learn more about knots, braids, and concordance by checking out Paula Truöl's research webpage.
List of Publications:
For more details you can consult my detailed list of publications, where you find abstracts and pictures.
My work is openly available on the ArXiv.

The ℤgenus of boundary links.
[ArXiv:2012.14367]
With JungHwan Park and Mark Powell. 
Examples of nonminimal open books with high fractional Dehn twist coefficient.
[ArXiv:2010.07869]
With Diana Hubbard. 
A note on the fourdimensional clasp number of knots.
[ArXiv:2009.01815]
With JungHwan Park. 
Existence of Embeddings of Smooth Varieties into Linear Algebraic Groups.
[ArXiv:2007.16164]
With Immanuel van Santen. 
Bouquets of curves in surfaces.
[ArXiv:2007.10429]
With Sebastian Baader and Levi Ryffel. 
Uniform models and short curves for random 3manifolds.
[ArXiv:1910.09486]
With Alessandro Sisto and Gabriele Viaggi. 
Embedding spheres in knot traces.
[ArXiv:2004.04204], accepted for publication in Compos. Math.
With Allison N. Miller, Matthias Nagel, Patrick Orson, Mark Powell, and Arunima Ray. 
Nonorientable slice surfaces and inscribed rectangles.
[ArXiv:2003.01590]
With Marco Golla. 
Genus one cobordisms between torus knots.
[ArXiv:1910.01672]
[IMRN]
With JungHwan Park. 
A note on the topological slice genus of satellite knots.
[ArXiv:1908.03760], accepted for publication in Algebr. Geom. Topol.
With Allison N. Miller and Juanita PinzonCaicedo. 
Balanced algebraic unknotting, linking forms, and surfaces in three and fourspace.
[ArXiv:1905.08305]
With Lukas Lewark. 
Almost positive links are strongly quasipositive.
[ArXiv:1809.06692]
With Lukas Lewark and Andrew Lobb. 
Up to topological concordance links are strongly quasipositive.
[ArXiv:1802.02493]
[J. Math. Pures Appl.]
With Maciej Borodzik. 
Calculating the homology and intersection form of a 4manifold from a trisection diagram.
[ArXiv:1711.04762]
[Proc. Natl. Acad. Sci. USA]
With Michael Klug, Trent Schirmer, and Drew Zemke. 
Braids with as many full twists as strands realize the braid index.
[ArXiv:1708.04998]
[J. Topol.]
With Diana Hubbard. 
On classical upper bounds for slice genera.
[ArXiv:1611.02679]
[Selecta Math.]
With Lukas Lewark. 
Khovanov width and dealternation number of positive braid links.
[ArXiv:1610.04534]
[Math. Res. Lett.]
With Sebastian Baader, Lukas Lewark, and Raphael Zentner. 
Uniqueness of Embeddings of the Affine Line into Algebraic Groups.
[ArXiv:1609.02113]
[J. Algebraic Geom.]
With Immanuel van Santen. 
On the Upsilon invariant and satellite knots.
[ArXiv:1604.04901]
[Math. Z.]
With JungHwan Park and Arunima Ray. 
On cobordisms between knots, braid index, and the Upsiloninvariant.
[ArXiv:1602.02637]
[Math. Ann.]
With David Krcatovich. 
On the topological 4genus of torus knots.
[ArXiv:1509.07634]
[Trans. Amer. Math. Soc.]
With Sebastian Baader, Lukas Lewark, and Livio Liechti. 
Alternating numbers of torus knots with small braid index.
[ArXiv:1508.05825]
[Indiana Univ. Math. J.]
With Simon Pohlmann and Raphael Zentner. 
On 2bridge knots with differing smooth and topological slice genera.
[ArXiv:1508.01431]
[Proc. Amer. Math. Soc.]
With Duncan McCoy.  A sharp signature bound for positive fourbraids. [ArXiv:1508.00418] [Q. J. Math.]
 The degree of the Alexander polynomial is an upper bound for the topological slice genus. [ArXiv:1504.01064] [Geom. Topol.]
 Optimal Cobordisms between Torus Knots. [ArXiv:1501.00483] [Comm. Anal. Geom.]

Holomorphically Equivalent Algebraic Embeddings.
[ArXiv:1409.7319]
With Immanuel van Santen. 
Signature and the Alexander polynomial. (An appendix to Livio Liechti's
`Signature, positive Hopf plumbing and the Coxeter transformation.'
[ArXiv:1401.5336]
[Osaka J. Math.])
With Livio Liechti.  The signature of positive braids is linearly bounded by their first Betti number. [ArXiv:1311.1242] [Internat. J. Math.]
 Gordian adjacency for torus knots. [ArXiv:1301.5248] [Algebr. Geom. Topol.]