SciPost Submission Page
Shift orbifolds, decompactification limits, and lattices
by Dan Israel, Ilarion Melnikov, Yann Proto
Submission summary
| Authors (as registered SciPost users): | Yann Proto |
| Submission information | |
|---|---|
| Preprint Link: | https://arxiv.org/abs/2502.18453v1 (pdf) |
| Date submitted: | Oct. 6, 2025, 4:44 p.m. |
| Submitted by: | Yann Proto |
| Submitted to: | SciPost Physics |
| Ontological classification | |
|---|---|
| Academic field: | Physics |
| Specialties: |
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| Approach: | Theoretical |
Abstract
We describe the general shift orbifold of a Narain CFT and use this to investigate decompactification limits in the heterotic Narain moduli space. We also comment on higher rank theories and describe some applications to the CFT based on the Leech lattice and its shift orbifolds.
Author indications on fulfilling journal expectations
- Provide a novel and synergetic link between different research areas.
- Open a new pathway in an existing or a new research direction, with clear potential for multi-pronged follow-up work
- Detail a groundbreaking theoretical/experimental/computational discovery
- Present a breakthrough on a previously-identified and long-standing research stumbling block
Current status:
Reports on this Submission
Strengths
1- The article is exceptionally clear and careful about all technical points, many of which are usually not explicitly written out in the literature.
2- The article presents in a very explicit way various useful technical connections between lattice theory and conformal field theory.
3- The article contains a thorough set of references including modern work on the topic, making it a particularly useful working reference.
Weaknesses
1- The main weakness of the article is that it does not present significantly novel results, but this is clearly acknowledged by the authors.
Report
Recommendation
Publish (easily meets expectations and criteria for this Journal; among top 50%)
Strengths
- clear general discussion of a class of heterotic orbifolds,
- poses an interesting problem concerning relation between even-self dual lattices and solves it in a insightful way connected to decompactification along an expectator circle.
Weaknesses
Report
$d$ dimensions. The latter, dubbed Narain CFT, is characterized by an even self-dual
lattice of signature $(d,16+d)$ and the shifts characterizing the action of the orbifold group are given in terms of lattice vectors. The construction is clearly explained in careful detail.
Although aspects of shift orbifolds have already been studied in the literature, this article
asks interesting questions and answers them in clever ways that make contact with decompactification
limits. In particular, the authors determine all shift orbifolds of order $k \le 5$ that exchange
the two heterotic lattices in 10 dimensions (the case $d=0$).
The authors also analyze shift orbifolds involving $c=24$ CFTs based on even self-dual lattices.
In particular, starting with the Leech lattice they find the corresponding Niemeier lattice upon
orbifolding.
The findings of this paper are of current interest as they have potential applications in the construction
of novel string compactifications. Moreover, they are neatly presented.
Publication in Scipost is recommended.
Requested changes
None
Recommendation
Publish (easily meets expectations and criteria for this Journal; among top 50%)