Surface Singularities in $${\mathbb R}^4$$ : First Steps Towards Lipschitz Knot Theory

2020 ◽  
pp. 157-166
Author(s):  
Lev Birbrair ◽  
Andrei Gabrielov
Keyword(s):  
Knot Theory ◽  
Surface Singularities

scholarly journals Topological Atomic Chains on 2D Hybrid Structure

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3289
Author(s):  
Tomasz Kwapiński ◽  
Marcin Kurzyna
Keyword(s):  
Tight Binding ◽  
Wide Band ◽  
Hybrid Structure ◽  
Spectral Density Function ◽  
Hybrid Structures ◽  
Function Technique ◽  
Edge States ◽  
Surface Singularities ◽  
Atomic Chains ◽  
Topological States

Mid-gap 1D topological states and their electronic properties on different 2D hybrid structures are investigated using the tight binding Hamiltonian and the Green’s function technique. There are considered straight armchair-edge and zig-zag Su–Schrieffer–Heeger (SSH) chains coupled with real 2D electrodes which density of states (DOS) are characterized by the van Hove singularities. In this work, it is shown that such 2D substrates substantially influence topological states end evoke strong asymmetry in their on-site energetic structures, as well as essential modifications of the spectral density function (local DOS) along the chain. In the presence of the surface singularities the SSH topological state is split, or it is strongly localized and becomes dispersionless (tends to the atomic limit). Additionally, in the vicinity of the surface DOS edges this state is asymmetrical and consists of a wide bulk part together with a sharp localized peak in its local DOS structure. Different zig-zag and armachair-edge configurations of the chain show the spatial asymmetry in the chain local DOS; thus, topological edge states at both chain ends can appear for different energies. These new effects cannot be observed for ideal wide band limit electrodes but they concern 1D topological states coupled with real 2D hybrid structures.

QFT and unification of knot theories

2014 ◽  
Vol 29 (24) ◽  
pp. 1430025
Author(s):  
Alexey Sleptsov
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Knot Theory ◽  
Topological Quantum Field Theory ◽  
Quantum Field ◽  
Knot Invariants ◽  
Topological Quantum

We discuss relation between knot theory and topological quantum field theory. Also it is considered a theory of superpolynomial invariants of knots which generalizes all other known theories of knot invariants. We discuss a possible generalization of topological quantum field theory with the help of superpolynomial invariants.

Weight Systems from Feynman Diagrams

1998 ◽  
Vol 07 (01) ◽  
pp. 61-85 ◽  
Author(s):  
Dirk Kreimer
Keyword(s):  
Field Theory ◽  
Knot Theory ◽  
Feynman Diagrams ◽  
Weight System ◽  
Term Relation ◽  
Renormalization Theory

We find that the overall UV divergences of a renormalizable field theory with trivalent vertices fulfil a four-term relation. They thus come close to establish a weight system. This provides a first explanation of the recent successful association of renormalization theory with knot theory.

scholarly journals ON -K2 FOR NORMAL SURFACE SINGULARITIES

1998 ◽  
Vol 09 (06) ◽  
pp. 653-668 ◽  
Author(s):  
HAO CHEN ◽  
SHIHOKO ISHII
Keyword(s):  
Lower Bound ◽  
Positive Integer ◽  
Rational Number ◽  
Accumulation Point ◽  
Normal Surface ◽  
Accumulation Points ◽  
Surface Singularities

In this paper we show the lower bound of the set of non-zero -K2 for normal surface singularities establishing that this set has no accumulation points from above. We also prove that every accumulation point from below is a rational number and every positive integer is an accumulation point. Every rational number can be an accumulation point modulo ℤ. We determine all accumulation points in [0, 1]. If we fix the value -K2, then the values of pg, pa, mult, embdim and the numerical indices are bounded, while the numbers of the exceptional curves are not bounded.

Disentangling Topological Puzzles by Using Knot Theory

2006 ◽  
Vol 79 (5) ◽  
pp. 368-375 ◽  
Author(s):  
Matthew Horak
Keyword(s):  
Knot Theory

COMPUTER AIDED KNOT THEORY USING MATHEMATICA AND MATHLINK

2002 ◽  
Vol 11 (06) ◽  
pp. 945-954 ◽  
Author(s):  
NORIKO IMAFUJI ◽  
MITSUYUKI OCHIAI
Keyword(s):  
Knot Theory ◽  
Computer Tool ◽  
The Public ◽  
Computer Aided ◽  
Data Files

We introduce a computer tool called Knot2000(K2K) which was developed for the purpose of support for the research of knot theory. K2K is a package on Mathematica in which consists of 19 functions and it has already been opened to the public with other external programs and data files. In this paper, we will describe focusing on the usages of each functions and some examples of effective ways to use K2K, and show its availability.

Sign in / Sign up

Export Citation Format

Share Document