PreprintCC BY 4.0arXiv
Remarks on refined scissors congruence group and the third homology of SL2
Abstract
This work revisits the key sufficient conditions on a ring A that guarantee the existence of the exact sequence H3(SM2(A), ℤ)→ H3(SL2(A), ℤ) → ℛℬ(A) → 0 and of the isomorphism H3(SL2(A), SM2(A); ℤ) ≃ ℛ𝒫1(A). We show that there are rings which satisfy the relations above but do not satisfy the condition that -1 is an square, for example some rings ℤ[1/m] and finite local rings. In addition, we study the special case of non-dyadic local fields with characteristic not 2, obtaining a refined Bloch-Wigner exact sequence when -1 is not an square.
Related
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BibTeX
@misc{perez2026remarks,
title = {{Remarks on refined scissors congruence group and the third homology of $\mathrmSL_2$}},
author = {Elvis Torres Pérez},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2608.08890},
eprint = {2608.08890},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2608.08890},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Remarks on refined scissors congruence group and the third homology of SL_2
AU - Elvis Torres Pérez
PY - 2026
DA - 2026/09/07
PB - arXiv
DO - 10.48550/arxiv.2608.08890
UR - https://arxiv.org/abs/2608.08890
AB - This work revisits the key sufficient conditions on a ring A that guarantee the existence of the exact sequence H_3(SM_2(A), ℤ)→ H_3(SL_2(A), ℤ) → ℛℬ(A) → 0 and of the isomorphism H_3(SL_2(A), SM_2(A); ℤ) ≃ ℛ𝒫_1(A). We show that there are rings which satisfy the relations above but do not satisfy the condition that -1 is an square, for example some rings ℤ[1/m] and finite local rings. In addition, we study the special case of non-dyadic local fields with characteristic not 2, obtaining a refined Bloch-Wigner exact sequence when -1 is not an square.
ER -