# Finite density ${\mathrm{QED}}_{1+1}$ near Lefschetz thimbles

## Abstract

One strategy for reducing the sign problem in finite-density field theories is to deform the path integral contour from real to complex fields. If the deformed manifold is the appropriate combination of Lefschetz thimbles—or somewhat close to them—the sign problem is alleviated. Gauge theories require generalizing the definition of thimble decompositions, and therefore it is unclear how to carry out a generalized thimble method. In this paper we discuss some of the conceptual issues involved by applying this method to QED _{1 + 1} at finite density, showing that the generalized thimble method yields correct results with less computational effort than standard methods.

- Authors:

- Publication Date:

- Research Org.:
- Univ. of Illinois, Chicago, IL (United States); George Washington Univ., Washington, DC (United States); Univ. of Maryland, College Park, MD (United States)

- Sponsoring Org.:
- USDOE; National Science Foundation (NSF)

- OSTI Identifier:
- 1467759

- Alternate Identifier(s):
- OSTI ID: 1498965

- Grant/Contract Number:
- [FG02-95ER40907; DE FG02-01ER41195; FG02-93ER-40762; FG02-01ER41195; FG02-93ER40762; PHY-1151648]

- Resource Type:
- Published Article

- Journal Name:
- Physical Review D

- Additional Journal Information:
- [Journal Name: Physical Review D Journal Volume: 98 Journal Issue: 3]; Journal ID: ISSN 2470-0010

- Publisher:
- American Physical Society

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

### Citation Formats

```
Alexandru, Andrei, Başar, Gökçe, Bedaque, Paulo F., Lamm, Henry, and Lawrence, Scott. Finite density QED 1 + 1 near Lefschetz thimbles. United States: N. p., 2018.
Web. doi:10.1103/PhysRevD.98.034506.
```

```
Alexandru, Andrei, Başar, Gökçe, Bedaque, Paulo F., Lamm, Henry, & Lawrence, Scott. Finite density QED 1 + 1 near Lefschetz thimbles. United States. doi:10.1103/PhysRevD.98.034506.
```

```
Alexandru, Andrei, Başar, Gökçe, Bedaque, Paulo F., Lamm, Henry, and Lawrence, Scott. Thu .
"Finite density QED 1 + 1 near Lefschetz thimbles". United States. doi:10.1103/PhysRevD.98.034506.
```

```
@article{osti_1467759,
```

title = {Finite density QED 1 + 1 near Lefschetz thimbles},

author = {Alexandru, Andrei and Başar, Gökçe and Bedaque, Paulo F. and Lamm, Henry and Lawrence, Scott},

abstractNote = {One strategy for reducing the sign problem in finite-density field theories is to deform the path integral contour from real to complex fields. If the deformed manifold is the appropriate combination of Lefschetz thimbles—or somewhat close to them—the sign problem is alleviated. Gauge theories require generalizing the definition of thimble decompositions, and therefore it is unclear how to carry out a generalized thimble method. In this paper we discuss some of the conceptual issues involved by applying this method to QED 1 + 1 at finite density, showing that the generalized thimble method yields correct results with less computational effort than standard methods.},

doi = {10.1103/PhysRevD.98.034506},

journal = {Physical Review D},

number = [3],

volume = [98],

place = {United States},

year = {2018},

month = {8}

}

DOI: 10.1103/PhysRevD.98.034506

*Citation information provided by*

Web of Science

Web of Science

#### Figures / Tables:

Works referenced in this record:

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journal, August 2017

- Alexandru, Andrei; Başar, Gökçe; Bedaque, Paulo F.
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##
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##
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##
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##
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##
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##
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##
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Figures / Tables found in this record:

*Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.*