English

The wall-chamber structures of the real Grothendieck groups

Representation Theory 2020-04-21 v2

Abstract

For a finite-dimensional algebra AA over a field KK with nn simple modules, the real Grothendieck group K0(projA)R:=K0(projA)ZRRnK_0(\operatorname{\mathsf{proj}} A)_\mathbb{R}:=K_0(\operatorname{\mathsf{proj}} A) \otimes_\mathbb{Z} \mathbb{R} \cong \mathbb{R}^n gives stability conditions of King. We study the associated wall-chamber structure of K0(projA)RK_0(\operatorname{\mathsf{proj}} A)_\mathbb{R} by using the Koenig--Yang correspondences in silting theory. First, we introduce an equivalence relation on K0(projA)RK_0(\operatorname{\mathsf{proj}} A)_\mathbb{R} called TF equivalence by using numerical torsion pairs of Baumann--Kamnitzer--Tingley. Second, we show that the open cone in K0(projA)RK_0(\operatorname{\mathsf{proj}} A)_\mathbb{R} spanned by the g-vectors of each 2-term silting object gives a TF equivalence class, and this gives a one-to-one correspondence between the basic 2-term silting objects and the TF equivalence classes of full dimension. Finally, we determine the wall-chamber structure of K0(projA)RK_0(\operatorname{\mathsf{proj}} A)_\mathbb{R} in the case that AA is a path algebra of an acyclic quiver.

Keywords

Cite

@article{arxiv.1905.02180,
  title  = {The wall-chamber structures of the real Grothendieck groups},
  author = {Sota Asai},
  journal= {arXiv preprint arXiv:1905.02180},
  year   = {2020}
}

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31 pages