Abstract
In this paper we propose a refinement of the heat-kernel/zeta function treatment of kink quantum fluctuations in scalar field theory, further analyzing the existence and implications of a zero-energy fluctuation mode. Improved understanding of the interplay between zero modes and the kink heat-kernel expansion delivers asymptotic estimations of one-loop kink mass shifts with remarkably higher precision than previously obtained by means of the standard Gilkey–DeWitt heat-kernel expansion.
Similar content being viewed by others
Notes
We pass to use QFT terminology: the linear waves in the quantized theory are the light mesons, whereas the minima of U are the vacua of the system.
The kinks are also static solutions of the PDE equation (3).
We refer to this formula as the first DHN formula, to be distinguished from the “second” DHN formula applicable to the quantum sine-Gordon breathers.
After all, it is an asymptotic series such that there is an optimum truncation order approximation to the exact value.
In [19] it is explained that these models are well defined only for |ϕ|≤1.
References
T.H.R. Skyrme, Proc. R. Soc. A 262, 233 (1961)
J.K. Perring, T.H.R. Skyrme, Nucl. Phys. 31, 550 (1962)
R. Dashen, B. Hasslacher, A. Neveu, Phys. Rev. D 10, 4130 (1974)
R. Dashen, B. Hasslacher, A. Neveu, Phys. Rev. D 12, 3424 (1975)
A. Alonso-Izquierdo, J.M. Guilarte, M.A.G. Leon, W.G. Fuertes, J.M. Muñoz-Casta neda, M. de la Torre Mayado, Lectures on the mass of topological solitons. arXiv:hep-th/0611180
J.M. Guilarte, A. Alonso-Izquierdo, W.G. Fuertes, M. de la Torre Mayado, M.J. Senosiain, in Proceedings of Science (ISFTG), vol. 013, (2009). 63pp
M. Bordag, A. Goldhaber, P. van Nieuwenhuizen, D. Vassilevich, Phys. Rev. D 66, 125014 (2002)
A. Alonso-Izquierdo, J.M. Guilarte, M.A.G. Leon, W.G. Fuertes, Nucl. Phys. B 635, 525–557 (2002)
P.B. Gilkey, Invariance Theory, the Heat Equation and the Atiyah–Singer Index Theorem (Publish or Perish, Houston, 1984)
J. Roe, Elliptic Operators, Topology and Asymptotic Methods (Longman Scientific and Technical, New York, 1988)
B.S. de Witt, Dynamical Theory of Groups and Fields (Gordon and Breach, New York, 1965)
I.G. Avramidi, Heat kernel approach in quantum field theory. Nucl. Phys. Proc. Suppl. 104, 3–32 (2002). arXiv:hep-th/0107018
E. Elizalde, S. Odintsov, A. Romeo, A. Bytsenko, S. Zerbini, Zeta Regularization Techniques with Applications (World Scientific, Singapore, 1994)
K. Kirsten, Spectral Functions in Mathematics and Physics (Chapman and Hall/CRC, New York, 2002)
D.V. Vassilevich, Phys. Rep. C 388, 279–360 (2003)
A. Alonso-Izquierdo, J.M. Guilarte, M.A.G. Leon, W.G. Fuertes, Nucl. Phys. B 638, 378–404 (2002)
A. Alonso-Izquierdo, J.M. Guilarte, M.A.G. Leon, W.G. Fuertes, Nucl. Phys. B 681, 163–194 (2004)
A. Alonso-Izquierdo, J.M. Guilarte, Nucl. Phys. B 852, 696–735 (2011)
A. Alonso-Izquierdo, J.M. Guilarte, Ann. Phys. (2012). doi:10.1016/j.aop.2012.04.014
K. Cahill, A. Comtet, R. Glauber, Mass formulas for static solitons. Phys. Lett. B 64, 283–385 (1976)
R. Rajaraman, Solitons and Instantons (North-Holland, Amsterdam, 1982)
P. Drazin, R. Johnson, Solitons: An Introduction (Cambridge University Press, Cambridge, 1996)
N. Manton, P. Sutcliffe, Topological Solitons. Cambridge Monographs on Mathematical Physics (Cambridge University Press, Cambridge, 2004)
G. Mussardo, Nucl. Phys. B 779, 101–154 (2007)
M. Lohe, Phys. Rev. D 20, 3120–3130 (1979)
Acknowledgements
We warmly thank our collaborators in previous research of this topic, W. Garcia Fuertes, M. Gonzalez Leon and M. de la Torre Mayado, for illuminating conversations about different aspects of this subject.
We also gratefully acknowledge that this work has been partially financed by the Spanish Ministerio de Educacion y Ciencia (DGICYT) under grant: FIS2009-10546.
Author information
Authors and Affiliations
Corresponding author
Appendix
Appendix
In this appendix we display a Mathematica code which automatizes the computation of the quantum correction to the kink mass in one-component scalar field theory by applying formula (42), derived from the modified asymptotic series approach. The algorithm is divided into three subroutines: the identification of the density coefficients c n (x,x)=0 C n (x) by means of (34); the computation of the Seeley coefficients by integrating the density coefficients, finally evaluating the formula (42) to obtain an estimation of the kink mass quantum correction.
-
Calculation of the c n (x,x) densities.
The following Mathematica code:
densitycoefficients[potential_, vacuum1_, vacuum2_, nmax_] := Module[{var1, var2, var3, tomax, d1, v, v0, oper, f0, f6, x7, coef, k, coa, j, co}, (var1[ph1_] = potential /. {y -> ph1}; var2[ph1_] = Simplify[PowerExpand[Sqrt[2 var1[ph1]]]]; var3[ph1_] = Sign[var2[(vacuum1 + vacuum2)/2]] var2[ph1]; coef = {}; v[x_] = Simplify[(D[var1[ph1], {ph1, 2}]) /. {ph1 -> ph1[x]}]; v0 = Sqrt[Simplify[(D[var1[ph1], {ph1, 2}]) /. {ph1 -> vacuum1}]]; f0[x_ ] = (var3[ph1]/(Sqrt[Integrate[var3[ph1], {ph1, vacuum1, vacuum2}]])) /. {ph1 -> ph1[x]}; d1[fun_] := Simplify[(D[fun, x]) /. {ph1’[x] -> var3[ph1[x]]}]; oper[fu8_, n1_] := Simplify[Nest[f6, x7, n1] /. {f6 -> d1, x7 -> fu8}]; tomax = 2 nmax; For[k = 0, k < tomax + 0.5, coa[0, k] = 0; k++]; coa[0, 0] = 1; co[n_, k_] := Simplify[(1/(n + k)) (coa[n - 1, k + 2] - Sum[Binomial[k, r5] oper[v[x] - v0^2, r5] coa[n - 1, k - r5], {r5, 0, k}] - 2 v0 f0[x] oper[f0[x], k] KroneckerDelta[0, n - 1] - f0[x] oper[f0[x], k] (1 + 2 k) (2^n (v0)^(2 n - 1))/((2 n - 1)!!))]; For[j = 1, j < nmax + 0.5, tomax = tomax - 2; For[k = 0, k < tomax + 0.5, coa[j, k] = co[j, k]; If[k == 0, coef = Append[coef, coa[j, 0]]]; k++]; j++]; Return[coef])];
defines the module densitycoefficients[potential_, vacuum1_, vacuum2_, nmax_], which performs the work of calculating the coefficients c n (x,x). The arguments of this computational function are potential, the U(y) potential written by prescription as a function of the y variable, vacuum1 and vacuum2, the two vacua connected by the kink solution in increasing order, and nmax, the N-order truncation chosen in the computation of ΔE(ϕ K ;N).
-
Calculation of the Seeley coefficients.
The Mathematica module seeleycoefficients[potential_, vacuum1_, vacuum2_, nmax_] depends on the same arguments as the previous one:
seeleycoefficients[potential_, vacuum1_, vacuum2_, nmax_] := Module[{coef, densi, f, f1, f2, a = {},j}, (coef = densitycoefficients[potential, vacuum1, vacuum2, nmax]; f1[y_] = Simplify[PowerExpand[Sqrt[2 potential]]]; f2[y_] = Sign[f1[(vacuum1 + vacuum2)/2]] f1[y]; For[j = 1, j < nmax + 0.5, f[y_] = Simplify[(coef[[j]] /. {ph1[x] -> y})/f2[y]]; a = Append[a, Integrate[f[y], {y, vacuum1, vacuum2}]]; j++]; Return[a])];
and provides us with the value of the Seeley coefficients. This subroutine calls the previous function in order to accomplishes its task.
-
Estimation of the quantum correction.
The subroutine quantumcorrection[potential_, vacuum1_, vacuum2_, nmax_],
quantumcorrection[potential_, vacuum1_, vacuum2_, nmax_] := Module[{v0, corr, a}, (v0 = Sqrt[Simplify[(D[potential, {y, 2}]) /. {y -> vacuum1}]]; a = Chop[seeleycoefficients[potential, vacuum1, vacuum2, nmax]]; corr = -(v0/Pi) - (1/(8. Pi)) (Sum[(a[[n]] (v0^(-2 n + 2)) Gamma[n - 1]), {n, 2, nmax}]); Return[corr])];
completes the work by providing us with the one-loop kink mass quantum correction in the (1+1) dimensional scalar field theory model characterized by the potential term U(y). This function calls the two previous ones.
The KinkMassQuantumCorrection_Modified.nb file containing this Mathematica code can be downloaded at the web page http://campus.usal.es/~mpg/General/Mathematicatools, which includes examples and demos. We recommend this option in order to avoid transcription errors in the code.
Rights and permissions
About this article
Cite this article
Izquierdo, A.A., Guilarte, J.M. Kink fluctuation asymptotics and zero modes. Eur. Phys. J. C 72, 2170 (2012). https://doi.org/10.1140/epjc/s10052-012-2170-3
Received:
Revised:
Published:
DOI: https://doi.org/10.1140/epjc/s10052-012-2170-3