On subflat domains of RD-flat modules

Year 2023, Volume: 72 Issue: 3, 563 - 569, 30.09.2023

Mücahit Bozkurt , Yilmaz Durğun

https://doi.org/10.31801/cfsuasmas.1229943

Abstract

The concept of subflat domain is used to measure how close (or far away) a module is to be flat. A right module is flat if its subflat domain is the entire class of left modules. In this note, we focus on of RD-flat modules that have subflat domain which is exactly the collection of all torsion-free modules, shortly tf-test modules. Properties of subflat domains and of tf-test modules are studied. New characterizations of left P-coherent rings and torsion-free rings by subflat domains of cyclically presented left $R$-modules are obtained.

Keywords

RD-flat module, subflat domain, torsion-free module

Supporting Institution

The Scientific and Technological Research Council of Turkey (TUBITAK)

Project Number

119F176

Thanks

We thank the Scientific and Technological Council of Turkey for supporting our study with project number 119F176.

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