# QCD sum rules for skeptics

## Abstract

A new Monte-Carlo based uncertainty analysis is introduced to quantitatively determine the predictive ability of QCD sum rules. A comprehensive analysis of ground state p-meson and nucleon spectral properties is performed. Many of the findings contradict the conventional wisdom of both practitioners and skeptics alike. Associations between the phenomenological fit parameters are particularly interesting as they reveal how the sum rules resolve the spectral properties. The use of derivative sum rules for the determination of p-meson spectral properties is shown to be a very unfavorable approach. Most prior nucleon sum rule analyses are based on a sum rule which is found to be invalid; the results are suspect, and should be reevaluated. The {open_quotes}Ioffe formula,{close_quotes} argued by many to qualitatively encapsulate a description of the nucleon mass in terms of the chiral symmetry breaking order parameter {l_angle}{bar q}q{r_angle} is misleading at best. QCD sum rules are found to be self-consistent without contributions from direct instantons. This implies that instanton effects are adequately accounted for in the nonperturbative vacuum condensates. This in-depth examination of QCD sum rule self consistency paints a favorable picture for further quantitative refinements of the QCD sum rule approach. {copyright} 1997 Academic Press, Inc.

- Authors:

- Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195 (United States)|[TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia V6T 2A3 (Canada)

- Publication Date:

- OSTI Identifier:
- 503552

- Resource Type:
- Journal Article

- Journal Name:
- Annals of Physics (New York)

- Additional Journal Information:
- Journal Volume: 254; Journal Issue: 2; Other Information: PBD: Mar 1997

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 66 PHYSICS; QUANTUM CHROMODYNAMICS; SUM RULES; MONTE CARLO METHOD; MESONS; NUCLEONS; GROUND STATES; HADRONS; QUARK MODEL; INSTANTONS

### Citation Formats

```
Leinweber, D.B.
```*QCD sum rules for skeptics*. United States: N. p., 1997.
Web. doi:10.1006/aphy.1996.5641.

```
Leinweber, D.B.
```*QCD sum rules for skeptics*. United States. doi:10.1006/aphy.1996.5641.

```
Leinweber, D.B. Sat .
"QCD sum rules for skeptics". United States. doi:10.1006/aphy.1996.5641.
```

```
@article{osti_503552,
```

title = {QCD sum rules for skeptics},

author = {Leinweber, D.B.},

abstractNote = {A new Monte-Carlo based uncertainty analysis is introduced to quantitatively determine the predictive ability of QCD sum rules. A comprehensive analysis of ground state p-meson and nucleon spectral properties is performed. Many of the findings contradict the conventional wisdom of both practitioners and skeptics alike. Associations between the phenomenological fit parameters are particularly interesting as they reveal how the sum rules resolve the spectral properties. The use of derivative sum rules for the determination of p-meson spectral properties is shown to be a very unfavorable approach. Most prior nucleon sum rule analyses are based on a sum rule which is found to be invalid; the results are suspect, and should be reevaluated. The {open_quotes}Ioffe formula,{close_quotes} argued by many to qualitatively encapsulate a description of the nucleon mass in terms of the chiral symmetry breaking order parameter {l_angle}{bar q}q{r_angle} is misleading at best. QCD sum rules are found to be self-consistent without contributions from direct instantons. This implies that instanton effects are adequately accounted for in the nonperturbative vacuum condensates. This in-depth examination of QCD sum rule self consistency paints a favorable picture for further quantitative refinements of the QCD sum rule approach. {copyright} 1997 Academic Press, Inc.},

doi = {10.1006/aphy.1996.5641},

journal = {Annals of Physics (New York)},

number = 2,

volume = 254,

place = {United States},

year = {1997},

month = {3}

}