#31558 closed defect (fixed)

homomorphism of extension fields do not preserve canonical embeddings of the base

Reported by: Vincent Delecroix Owned by:
Priority: blocker Milestone: sage-9.3
Component: number fields Keywords:
Cc: Markus Wageringel, Marc Mezzarobba Merged in:
Authors: Vincent Delecroix Reviewers: Samuel Lelièvre
Report Upstream: N/A Work issues:
Branch: e2efadf (Commits, GitHub, GitLab) Commit: e2efadfbfb5f78536a634e5845a0f679a96cd331
Dependencies: Stopgaps:

Status badges

Description (last modified by Samuel Lelièvre)

Define a quadratic extension of ℚ[i] and two homomorphisms to QQbar:

sage: K.<i> = QuadraticField(-1, embedding=QQbar.gen())
sage: L.<a> = K.extension(x^2 - 6*x - 4)
sage: a0, a1 = a.galois_conjugates(QQbar)
sage: f0 = hom(L, QQbar, a0)
sage: f1 = hom(L, QQbar, a1)

Observed: wrong embedding:

sage: f0(i)  # wrong embedding
0.?e-54 - 1.000000000000000?*I
sage: f1(i)  # wrong embedding
0.?e-54 - 1.000000000000000?*I

Expected: correct embedding:

sage: f0(i)
0.?e-54 + 1.000000000000000?*I
sage: f1(i)
0.?e-54 + 1.000000000000000?*I

Change History (11)

comment:1 Changed 19 months ago by Vincent Delecroix

Branch: u/vdelecroix/31558
Commit: cf668005799173205566b30be5bf0559752f14c9
Status: newneeds_review

New commits:

cf6680030518: choose coerce embedding for the base when it exists

comment:2 Changed 19 months ago by git

Commit: cf668005799173205566b30be5bf0559752f14c98c9390cf491f4c576f798bc40069ac7992d6db53

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

8c9390c31558: choose coerce embedding for the base when it exists

comment:3 Changed 19 months ago by Vincent Delecroix

Description: modified (diff)

comment:4 Changed 19 months ago by Vincent Delecroix

Description: modified (diff)

comment:5 Changed 19 months ago by git

Commit: 8c9390cf491f4c576f798bc40069ac7992d6db53e2efadfbfb5f78536a634e5845a0f679a96cd331

Branch pushed to git repo; I updated commit sha1. This was a forced push. New commits:

e2efadf31558: choose coerce embedding for the base when it exists

comment:6 Changed 19 months ago by Vincent Delecroix

Description: modified (diff)

comment:7 Changed 19 months ago by Samuel Lelièvre

Description: modified (diff)
Reviewers: Samuel Lelièvre
Status: needs_reviewpositive_review

comment:8 Changed 19 months ago by Vincent Delecroix

Priority: majorcritical

Let us try to make it to 9.3 since this is a bug with a mostly trivial fix.

comment:9 Changed 19 months ago by Vincent Delecroix

(et merci pour la review Samuel :)

comment:10 Changed 19 months ago by Matthias Köppe

Priority: criticalblocker

Setting priority to blocker to bring this ticket to the attention of the release bot.

comment:11 Changed 18 months ago by Volker Braun

Branch: u/vdelecroix/31558e2efadfbfb5f78536a634e5845a0f679a96cd331
Resolution: fixed
Status: positive_reviewclosed
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