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Title: The local-global conjecture for Apollonian circle packings is false
In a primitive integral Apollonian circle packing, the curvatures that appear must fall into one of six or eight residue classes modulo 24. The local-global conjecture states that every sufficiently large integer in one of these residue classes appears as a curvature in the packing. We prove that this conjecture is false for many packings, by proving that certain quadratic and quartic families are missed. The new obstructions are a property of the thin Apollonian group (and not its Zariski closure), and are a result of quadratic and quartic reciprocity, reminiscent of a Brauer-Manin obstruction. Based on computational evidence, we formulate a new conjecture.  more » « less
Award ID(s):
1652238 2401580
PAR ID:
10552281
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Annals of Mathematics
Date Published:
Journal Name:
Annals of Mathematics
Volume:
200
Issue:
2
ISSN:
0003-486X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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