History of Real periods of elliptic curves over $\mathbb{Q}$ of rank $3$

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compare when who what
2026-08-17 13:31 bmatschke how well the digits are known: proven (verified here against arb ball agm, all entries; curve rebuilt from its c-invariants) current
2026-08-15 11:01 bmatschke how well the digits are known: heuristic (agreement-checked) (two precisions, agreement asserted; arb could prove this one)
2026-08-13 22:07 bmatschke how well the digits are known: assumed-bound (interval widened by a hand-chosen 4 ulps (blur_real_interval))
2026-08-09 09:15 flattening entries rewritten as records with named parameters
2026-08-09 08:35 data-repository import the current state of the data repository reviewed
2021-05-08 23:05 bmatschke from the data repository, c3109fcf

What changed between 2026-08-15 11:01 and 2026-08-17 13:31

from line 55 (12 lines) @@ -55,12 +55,12 @@
   sources:   - CITE{LMFDB} (list of curves with bounded conductor)-  rigour: heuristic (agreement-checked)-  rigour details: 'Computed at two working precisions and written only after the two-    agreed. The underlying computation is pi divided by an arithmetic-geometric mean-    in ordinary floating point: quadratically convergent and about as well behaved-    as a transcendental computation gets, but with no error bound carried through-    it. This one could be proven -- arb implements the AGM in ball arithmetic, and-    at 700 bits gives the real period to 695 accurate bits from exact algebraic input-    -- and should be, when a generator replaces the script.'+  rigour: proven+  rigour details: Recomputed in ball arithmetic and verified entry by entry. Sage+    computes the real period as pi divided by an arithmetic-geometric mean in ordinary+    floating point, with no error bound carried through it; arb has the agm in ball+    arithmetic, so the same identity applied to the curve's exact algebraic invariants+    gives an enclosure instead. Every entry of this table agrees with one, at around+    395 accurate bits out of 400. The curve is taken from the entry's own c-invariants,+    which determine it, and its conductor checked against the entry's N. Display properties:   number-header: $\omega_1$ 

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