Bi‐embeddability spectra and bases of spectra

@article{Fokina2018BiembeddabilitySA,
  title={Bi‐embeddability spectra and bases of spectra},
  author={Ekaterina B. Fokina and Dino Rossegger and Luca San Mauro},
  journal={Mathematical Logic Quarterly},
  year={2018},
  volume={65}
}
We study degree spectra of structures with respect to the bi‐embeddability relation. The bi‐embeddability spectrum of a structure is the family of Turing degrees of its bi‐embeddable copies. To facilitate our study we introduce the notions of bi‐embeddable triviality and basis of a spectrum. Using bi‐embeddable triviality we show that several known families of degrees are bi‐embeddability spectra of structures. We then characterize the bi‐embeddability spectra of linear orderings and study… 

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