In the branch of
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
called
knot theory
In the mathematical field of topology, knot theory is the study of knot (mathematics), mathematical knots. While inspired by knots which appear in daily life, such as those in shoelaces and rope, a mathematical knot differs in that the ends are ...
, the volume conjecture is the following open problem that relates
quantum invariants of knots to the
hyperbolic geometry of
knot complement
In mathematics, the knot complement of a tame knot ''K'' is the space where the knot is not. If a knot is embedded in the 3-sphere, then the complement is the 3-sphere minus the space near the knot. To make this precise, suppose that ''K'' is a ...
s.
Let ''O'' denote the
unknot
In the mathematical theory of knots, the unknot, not knot, or trivial knot, is the least knotted of all knots. Intuitively, the unknot is a closed loop of rope without a knot tied into it, unknotted. To a knot theorist, an unknot is any embe ...
. For any knot ''K'' let
be Kashaev's invariant of
; this invariant coincides with the following evaluation of the
-
Colored Jones Polynomial of
:
Then the volume conjecture states that
where vol(''K'') denotes the
hyperbolic volume
In the mathematical field of knot theory, the hyperbolic volume of a hyperbolic link is the volume of the link's complement with respect to its complete hyperbolic metric. The volume is necessarily a finite real number, and is a topological inv ...
of the complement of ''K'' in the
3-sphere
In mathematics, a 3-sphere is a higher-dimensional analogue of a sphere. It may be embedded in 4-dimensional Euclidean space as the set of points equidistant from a fixed central point. Analogous to how the boundary of a ball in three dimensi ...
.
Kashaev's Observation
observed that the asymptotic behavior of a certain state sum of knots gives the
hyperbolic volume
In the mathematical field of knot theory, the hyperbolic volume of a hyperbolic link is the volume of the link's complement with respect to its complete hyperbolic metric. The volume is necessarily a finite real number, and is a topological inv ...
of the complement of knots
and showed that it is true for the knots
,
, and
. He conjectured that for the general
hyperbolic knot
Hyperbolic is an adjective describing something that resembles or pertains to a hyperbola (a curve), to hyperbole (an overstatement or exaggeration), or to hyperbolic geometry.
The following phenomena are described as ''hyperbolic'' because they ...
s the formula (2) would hold. His invariant for a knot
is based on the theory of
quantum dilogarithm In mathematics, the quantum dilogarithm is a special function defined by the formula
:
\phi(x)\equiv(x;q)_\infty=\prod_^\infty (1-xq^n),\quad , q, 0.
References
*
*
*
*
*
*
*
External links
* {{nlab, id=quantum+dilogarithm, title=quantum ...
s at the
-th root of unity,
.
Colored Jones Invariant
had firstly pointed out that Kashaev's invariant is related to the
colored Jones polynomial by replacing q with the 2N-root of unity, namely,
. They used an
R-matrix The term R-matrix has several meanings, depending on the field of study.
The term R-matrix is used in connection with the Yang–Baxter equation. This is an equation which was first introduced in the field of statistical mechanics, taking its n ...
as the
discrete Fourier transform
In mathematics, the discrete Fourier transform (DFT) converts a finite sequence of equally-spaced samples of a function into a same-length sequence of equally-spaced samples of the discrete-time Fourier transform (DTFT), which is a complex- ...
for the equivalence of these two values.
The volume conjecture is important for
knot theory
In the mathematical field of topology, knot theory is the study of knot (mathematics), mathematical knots. While inspired by knots which appear in daily life, such as those in shoelaces and rope, a mathematical knot differs in that the ends are ...
. In section 5 of this paper they state that:
: Assuming the volume conjecture, every knot that is different from the
trivial knot
In the mathematical theory of knots, the unknot, not knot, or trivial knot, is the least knotted of all knots. Intuitively, the unknot is a closed loop of rope without a knot tied into it, unknotted. To a knot theorist, an unknot is any embe ...
has at least one different
Vassiliev (finite type) invariant.
Relation to Chern-Simons theory
Using complexification, rewrote the formula (1) into
where
is called the
Chern–Simons invariant. They showed that there is a clear relation between the complexified colored Jones polynomial and Chern–Simons theory from a mathematical point of view.
References
*.
*.
*.
*{{citation
, last1 = Gukov , first1 = Sergei
, doi = 10.1007/s00220-005-1312-y
, arxiv = hep-th/0306165
, issue = 1
, journal = Commun. Math. Phys.
, pages = 557-629
, title = Three-Dimensional Quantum Gravity, Chern-Simons Theory, And The A-Polynomial
, volume = 255
, year = 2005, bibcode = 2005CMaPh.255..577G.
Knot theory
Conjectures
Unsolved problems in geometry