Two ranks count different things
Mordell–Weil rank counts independent rational generators. Analytic rank counts the vanishing order of L(E,s) at 1. BSD predicts these integers agree for every E/Q.
Limit A set of independent points gives a rank lower bound; a rigorous equality also needs an upper bound. Approximate L-values do not certify an exact vanishing order.
- Rational points form a finitely generated group (Proved)
- BSD rank equality holds for every E/Q (Open)
Sources & review
Supporting statements
- Wiles · official BSD description ↗PDF page 1: Mordell theorem and rank definition
- Wiles · official BSD description ↗PDF page 2: rank conjecture; all finite Euler factors restored for the standard L-function
Source-grounded explanation · independent explanation review: pending.