Skip to content

LLewark/galg-taylor-table

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

5 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

What is this repository for?

This website lists the values of the algebraic genus [FL18] and the Taylor invariant [Tay77] for all prime knots with crossing number 12 or less. Details about how these values were computed are contained in the papers [LM19, FL19].

The Taylor invariant is the best lower bound for the topological (or smooth) slice genus that can be read off the S-equivalence class of the Seifert matrix (or equivalently, the isometry class of the Blanchfield pairing) [Tay77]. The algebraic genus is an upper bound for the topological slice genus; it may also be read off the S-equivalence class of the Seifert matrix. The algebraic genus of a knot K is in fact equal to its ℤ-slice genus [FL19], which is the minimal genus of a topological slice surface of K whose complement has fundamental group isomorphic to ℤ.

[FL18] [On classical upper bounds for slice genera] by P. Feller and L. Lewark, Selecta Math. 24 (2018), no. 5, 4885–4916. MR3874707, Zbl 1404.57008, arXiv: 1611.02679.

[Tay77] [On the genera of knots] by L. R. Taylor, In Topology of low-dimensional manifolds (Proc. Second Sussex Conf., Chelwood Gate, 1977), volume 722 of Lecture Notes in Math., pages 144–154. Springer, Berlin, 1979. MR0547461, Zbl 0409.57021.

[FL19] [Balanced algebraic unknotting, linking forms, and surfaces in three- and four-space] by P. Feller and L. Lewark, accepted in J. Differential Geom. arXiv:1905.08305.

[LM19] [On calculating the slice genera of 11- and 12-crossing knots] by L. Lewark and D. McCoy, Exp. Math. 28 (2019), no. 1, 81–94. MR3938580, Zbl 1414.57009, arXiv:1508.01098.

The table is available here:

https://llewark.github.io/galg-taylor-table/.

What are the other files for?

The table is generated from the source file data.csv by running the script converter.py:

./converter.py data.csv > index.html

Acknowledgments

This script is a modified copy of a script written by Claudius Zibrowius for a similar online table.

While working on this program, Lukas Lewark was supported by the Emmy Noether Programme of the DFG, project number 412851057.

About

Table of values of g_alg and the Taylor invariant

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

 
 
 

Contributors

Languages