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Kleinert. Path integrals book, Chapters 10 to 21(T)(622s).djvu



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One important step towards distinguishing different equivalence classes of simple and
compound knots is the knot group defined as follows...
If the underpass is nontrivial, the nonvanishing
row elements are
Au = l, Aii+1 = —t, Aik = t - 1, type r (right to left),
An = -t, Aii+1 = 1, Aik = t-1, type 1 (left to right)...
Polymers and Particle Orbits in Multiply Connected Spaces
10 11 12 13
Figure 16.11 Kauffman decomposition of trefoil knot...
Together with the
cotorsion w = —2, this amounts to an X-polynomial X(a) = —a10 — a2 and the Jones polynomial
JLo(t) = -Vt(l +t2) as in A6.129)...
are distinguished by the
Jones and the HOMFLY polynomials; the latter are
M = Bt2 - t4 + t2a2J,
a) = (^2 - t4 + tV)Br2 - t~4 + tV); A6.135)
the former are obtained by inserting a = t1!2 — t~xl2...
The molecules of DNA, the carriers of genetic
information on the structure of living organisms, can be considered as ribbons...
The Alexander polynomial A(s, t) is again given
by any (n — 1) x (n — l)-subdeterminant of the n x n-matrix A^...
A6.160)
The remainder is called the twist of the ribbon, defined by
Tw = i-?drx(r) • [n(r) x n(r)]/|x(r)|...
In the singular part, we approximate
x(t) within the small neighborhood A6.165) by the straight line
x(t) « x(t')...
Due to their nontopological nature
discussed earlier, these have no quantized values and must be avoided...
A6.189)
If we choose the gauge fields to be transverse, as in A6.177), we obtain with the
same technique as before the correlation functions of the gauge fields
?>^(x, x') = (A?(x)A?(x')), a,b= 1,2 A6.190)
are
?>i{(x,x') = 0, Dg(x,x!)=0, A6.191)
17The development in this Section follows F...
Only a calcu-
calculation of the second topological moment is possible with limited effort...
The expectation value is calculated for
any fixed pair (cti, a2) of replica labels, i.e., replica labels are not subject to Einstein's
summation convention of repeated indices...
If the polymer lengths are much larger than the persistence length one can ignore
the fact that the monomers have a finite size and it is possible to compute C(t, t')
analytically, leading to
A6.250)
where K is the constant
and B(a, b) = T(a)T(b)/T(a + b) is the Beta function...
As in A6.291), the vector x' on the left-hand side has to be carried around x in
the anticlockwise sense...
A6.319)
O7TC J
To add the Chern-Simons action, we restrict the spacetime dimensionality to 3...
For
a consistent gauge fixing, this volume has to be divided out of the gauge-fixing
functional as was first shown by Fadeev and Popov.22 For an adequate discussion of
this interesting topic which lies beyond the scope of this quantum-mechanical text
the reader is referred to books on quantum field theory...
A similar separation occurs in the time evolution amplitude which decomposes
into the sum of the amplitudes of the individual oscillators
(xbtb\xata) »• (xbtb\xata)_ + (xbtb\xata)+ A7.7)
= [Vx(t)exp\- I '" dt-[x2 - uu2(x + aJ]) + (a -> -a)...
These solutions cross the barrier and read, in the
limit L —> oo,
x(T) = x%{t) = ±atanh[o;(r - ro)/2], A7.20)
with an arbitrary parameter t$ specifying the point on the imaginary time axis where
the crossing takes place...
Kleinert, PATH INTEGRALS
17.2 Classical Solutions — Kinks and Antikinks
1099
Figure 17.3 Reversed double-well potential governing motion of position x as function
of imaginary time r...
The fluctuation
factor of a pure harmonic oscillator of frequency co and unit mass has been calculated
in Section 2.4 with the result
o * \ r
2nh sinh u>L
A7.36)
The leading exponential at large L displays the ground state energy u>/2, while the
corrections contain all information on the exited states whose energy is (n + l/2)u>
with rc= 1,2,3,......




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