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Quadratic spaces and Selmer groups of abelian varieties with multiplication

T0 review · 2 major / 4 minor · reviewed 2026-08-16 · deepseek-v4-flash

Pith's one-line read For abelian varieties with multiplication, the adelic p-torsion cohomology carries a metabolic orthogonal, symplectic, or unitary quadratic structure, and the Selmer group is the intersection of two maximal isotropic subspaces.

desk verdict Genuine extension of Poonen-Rains to RM/CM abelian varieties, but the p=2 orthogonal case has a false Galois-equivariance claim in Proposition 3.11(1) that leaves Theorem 5.7 unproven in that case. read the letter →

arxiv 2504.21272 v2 pith:LOPSFW5B submitted 2025-04-30 math.NT

classification math.NT MSC 11G1011E0411G0514K1514K22
keywords SelmergroupsquadraticformsabelianvarietiesrealmultiplicationcomplexWeilpairingShafarevich-Tateisotropicsubspaces
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper establishes the arithmetic quadratic-space picture of Selmer groups for abelian varieties that carry extra endomorphisms, not just for elliptic curves and hyperelliptic Jacobians. For an abelian variety A over a global field F with a symmetric isogeny λ and an order O in its endomorphism algebra stable under the Rosati involution, the adelic cohomology $H^{1}$(A_F,A[p]) is shown to be a metabolic quadratic space of orthogonal, symplectic, or unitary type. The p-Selmer group, modulo the p-primary Tate-Shafarevich obstruction, is then the intersection of two maximal isotropic subspaces: the Kummer image and the image of global cohomology. If this holds, random maximal isotropic subspace models for Selmer ranks extend to families with real or complex multiplication, and the primary parts of Shafarevich-Tate groups acquire a self-dual M⊕M shape.

What carries the argument

The load-bearing object is the form parameter Λ of the finite residue field k together with the pairings that it makes quadratic. The Rosati-involution-compatible multiplication by O on the p-adic Tate module gives an extended Weil pairing Θ^λ_{p_0} valued in O_{p_0}(1), whose reduction modulo p produces the local pairing h_v on $H^{1}$(F_v,A[p]). Quadratic refinements, supplied by $\theta$ groups and, in the p=2 orthogonal case, by line bundles L(a) with φ_{L(a)}=λa, turn these even hermitian forms into genuine quadratic spaces, and trace compatibility lifts the F_p-quadratic structure to k. Local Tate duality makes each local Kummer image self-orthogonal, the restricted product over all places is metabolic, and global Poitou-Tate duality makes the image of global cohomology self-orthogonal, so Sel_p(A)/$X^{1}$(F,A[p]) becomes L∩W.

What would settle it

Take an abelian variety A over a global field F with real multiplication by an order O of totally real degree equal to dim A, with p=2 prime to the discriminant of O, and compute dim Sel_2(A) and dim(L∩W) in $H^{1}$(A_F,A[2]). The theorem predicts these are equal; any example where they differ breaks the central isomorphism.

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Extended reading notes

Core claim

The central theorem states that, under suitable hypotheses, the adelic space $H^{1}$(A_F,A[p]) is a metabolic orthogonal, symplectic, or unitary k-space depending on whether the Rosati involution is trivial on K, p is ramified, or p is inert in K/K_0, and that Sel_p(A)/$X^{1}$(F,A[p]) ≅ L∩W, where L is the product of local Kummer images and W is the image of $H^{1}$(F,A[p]). In the split case p_0 splits in K/K_0, the same conclusion holds for $H^{1}$(A_F,A[p_0]) with a split unitary structure. For p=2, the orthogonal case requires a rational symmetric line bundle inducing λ, and the symplectic case requires the pair (A,λ) to be quadratic at every place; the paper proves these conditions in several arithmetic situations, including when [K:Q] equals dim A or 2 dim A. The corresponding structural result for Shafarevich-Tate groups is that X(A)/div[p^∞] is isomorphic to M⊕M for a finite O_0-module M in the covered cases.

Load-bearing premise

The construction needs quadratic refinements of λ at every local place, which for p=2 is imposed as a rational symmetric line bundle in the orthogonal case and as vanishing of all local obstructions c_{λ,v} in the symplectic case; if these conditions fail, the adelic quadratic structure and the Selmer intersection statement are not established.

Editorial extensions

If this is right

  • For every covered triple (A,λ,O), the rank of Sel_p(A) is the dimension of L∩W, and when X^1(F,A[p])=0 the Selmer group itself is described this way.
  • Families of abelian varieties with real multiplication by a fixed order O admit a conjectural distribution of dim Sel_p given by the orthogonal distribution D^Ort_q, while CM families in the ramified and inert cases correspond to symplectic and unitary distributions.
  • In the split unitary case, maximal isotropic subspaces are parameterized by ordinary subspaces of a k_0-space, so the relevant limit distributions are the co-rank distributions of random matrices over k_0, connected to Rogers-Ramanujan-type identities.
  • The p-primary component X(A)/div[p^∞] is a self-dual module M⊕M in the stated conditions, giving parity constraints and even dimensions over O_0/p_0.
  • For p=2 with [K:Q]=dim A and odd discriminant, the results imply the existence of rational theta characteristics in the branched-covering examples, and finiteness of X(A) forces X(A) to have the form M⊕M.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Because both L and W are O-stable, a faithful random model for these families should sample only maximal isotropic subspaces that are O-submodules; for O strictly larger than Z this sample space is much smaller than the full Grassmannian, so observed Selmer-rank distributions should deviate from the plain orthogonal distribution as [K:Q] grows.
  • A computable test of the theory is to work out the local obstruction c_{λ,v} at bad-reduction places for p=2 in the symplectic case; the theorem predicts vanishing everywhere, so any nonzero value would force a different global mechanism.
  • In the split unitary case, the Rogers-Ramanujan-type identity suggests that Selmer ranks in twist families of CM abelian varieties are governed by a random-subspace model rather than a classical random-matrix model, which could be probed by comparing the generating functions for explicit families.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

2 major / 4 minor

Summary. The paper extends the Poonen–Rains quadratic-space framework from elliptic curves to abelian varieties carrying an order O in a number field inside their endomorphism algebra, for a symmetric isogeny λ whose Rosati involution stabilizes O. It constructs metabolic orthogonal, symplectic, unitary, or split-unitary structures on the adelic cohomology group H^1(A_F, A[p]), proves under certain p=2 hypotheses that the Selmer group is the intersection of two maximal isotropic subspaces, and derives consequences for the structure of Shafarevich–Tate groups. Section 2 develops a self-contained combinatorial and topological theory of quadratic spaces over finite fields, including new split-unitary distributions and a Rogers–Ramanujan identity. The main arithmetic results are Theorems 3.12, 5.7, and 6.2, with conditional hypotheses needed in the p=2 orthogonal and symplectic cases.

Significance. If the main theorems are correct, this is a substantial extension of the Poonen–Rains Selmer-group model to abelian varieties with real and complex multiplication, and it gives new conjectural distributions (Conjecture 1.6) for Selmer ranks in RM families. The paper also contributes interesting structural results for Shafarevich–Tate groups, and Section 2 contains useful and apparently correct combinatorial material, including explicit formulas for split-unitary maximal-isotropic intersections. The proof architecture is coherent: local duality gives local quadratic structures, the restricted product gives the adelic space, and the Cassels–Tate argument gives the Shafarevich–Tate structure. However, one load-bearing proof step in the p=2 orthogonal case is invalid as written, and another step in the proof of Theorem 3.12 is incomplete. These issues are local and appear repairable, but they must be fixed before the stated theorems can be accepted.

major comments (2)
  1. [§3.3, Proposition 3.11(1)] The proof that the quadratic map q is Galois equivariant is incorrect. After choosing a basis e1, e2 with θ(e1, e2) = 1⊗−1, the paper defines q(ae1+be2) = ab⊗−1 and asserts that q is Galois equivariant because θ is. This does not follow: for a Galois element σ with σ(e1)=e1+e2 and σ(e2)=e2, which is a transvection in Sp_2(F_2), one has q(σe2)=q(e1+e2)=1 while σ(q(e2))=0. The equality q(σx)=σ(q(x)) fails whenever the chosen basis is not Galois-stable, and the coordinates of σx are not simply σ(a), σ(b). This claim is the sole input to Theorem 3.12 in the case †=1, and through Theorem 3.12 it is used in Proposition 4.7(2), Corollary 1.4, and Theorem 5.7 for p=2 orthogonal spaces. The proposition is likely salvageable: the quadratic form q(v)=1 for every nonzero v in A[p] has Arf invariant one and is invariant under all of Sp_2(F_2), so it is a valid Galois-equivariant refinement of the given alternating form. The proof as written, however, does not establish the claim and must be repaired.
  2. [§3.3, Theorem 3.12 (split primes)] In the proof of Theorem 3.12, after the decomposition 2O = p_1⋯p_r q_1 q_1^†⋯q_s q_s^†, the paper states that e^µ_qj + e^µ_qj† has the quadratic refinement (x,y) ↦ e^µ_qj(x,y). This is not a valid definition of a quadratic refinement: a quadratic refinement is a function of one variable, not of two variables, and the identity q(x+y)=q(x)q(y)β(x,y) is not verified for the proposed map. This step is used to prove c_µ=0 for the split prime ideals above 2 in the case †≠1, and therefore it is load-bearing for Theorem 3.12. The intended construction may be standard, but the present text does not supply the needed argument; please replace this sentence with a complete verification or a precise reference.
minor comments (4)
  1. [§1, MSC line] The word 'Primiary' in the Mathematics Subject Classification line should be 'Primary'.
  2. [§4.3, Proposition 4.7(1)] The displayed equality in the proof of Proposition 4.7(1) is garbled: the text appears to claim e^λ_p = e^{2λ}|_{A[p]×A[p]} = e^λ_2|_{A[p]×A[p]}, which is not meaningful as printed. Please restate the precise intended relationship between e^λ_p and e^λ_2.
  3. [§2.5, paragraph before Proposition 2.22] The word 'Theoreom' should be 'Theorem' in the sentence citing Theorem 2.13.
  4. [§1.3.2] The companion paper [59] is cited for the distribution of Selmer ranks in CM twist families; since that paper is not yet published, please state explicitly which results from [59] are assumed and which are merely anticipated.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity: the Selmer-intersection theorem is a conditional structural result built from standard duality and explicit hypotheses, not from a fit or self-citation.

full rationale

The paper's central claim (Theorem 5.7, Corollary 1.4) is conditional: the quadratic k-space structure is constructed from Weil pairings, local Tate duality, and the theta-group/line-bundle input of Poonen-Rains [50]/[49], with the p=2 orthogonal case explicitly assuming hypothesis (L) and the symplectic case assuming quadraticity everywhere. The isomorphism Sel_p(A)/X^1(F,A[p]) is isomorphic to L∩W is indeed a diagram chase from the Kummer sequence once L and W are defined, but the paper does not present it as an independent prediction; the substantive content is the metabolic structure and maximal isotropy of L and W, which are proved from local/global duality. The only self-citation, [59], is a forward reference to the author's companion work on distributions of Selmer ranks in CM twist families; it is contextual and not load-bearing for the theorems proved here. The proof issue in Proposition 3.11(1) noted by the skeptic concerns the Galois-equivariance of a coordinate-defined quadratic refinement; that is a possible correctness defect, not an equivalence of the claimed conclusion with its inputs. Because no derivation step reduces to a fitted parameter, a definitional renaming of a known result, or a load-bearing self-citation, the circularity score is 0.

Assumptions & free parameters 0 free parameters · 6 assumptions · 0 invented entities

The central theorems rest on standard arithmetic duality theorems and on the explicit p=2 hypotheses. No numerical parameters are fitted to data, and the paper introduces no new physical or algebraic entities with independent evidence requirements beyond the quadratic structures it constructs.

assumptions (6)
  • standard math Local Tate duality for finite flat group schemes over p-adic fields and for abelian varieties over local fields is valid.
    Invoked in Section 5.1 to show local Kummer images are self-orthogonal (Proposition 5.5) and to define nondegenerate local pairings h'_v and h_v.
  • standard math Global Poitou-Tate duality and the Brauer reciprocity law hold for the global field F.
    Used in the proof of Theorem 5.7 to prove the image of global cohomology W is maximal isotropic and, in the p=2 orthogonal case, that q'(W)=0 via the exact sequence for Brauer groups.
  • standard math The theta group and quadratic refinement machinery of Poonen-Rains [49,50] is valid: a symmetric isogeny lambda has a quadratic refinement over S exactly when the class c_lambda vanishes.
    Used in Propositions 3.8, 4.2, and 4.5 to turn vanishing of c_lambda into quadratic maps on local and adelic cohomology.
  • standard math The classification of nondegenerate quadratic spaces in hermitian categories of locally compact vector spaces over finite fields (Bak [5], Scharlau [55]) is correct.
    The entire Section 2.2 and Table 1 rest on this classification, including the form parameter Lambda and the dictionary delta = 0, 1/2, 1.
  • domain assumption For p=2, the hypotheses (L) in the orthogonal case and 'quadratic everywhere' in the symplectic case hold for the varieties under consideration in the unconditional corollaries.
    Theorem 5.7 is explicitly conditional on these. The paper proves them under extra conditions (Theorem 3.12, Proposition 4.7), but not in full generality, so the Selmer intersection theorem as stated depends on them.
  • domain assumption For the Shafarevich-Tate results, the characteristic of F and the discriminant of O satisfy the stated coprimality conditions, and lambda is induced from a rational symmetric line bundle in the p=2 cases.
    Theorems 6.2 and Corollary 6.4 require these to ensure the Cassels-Tate pairing is alternating and the module structure M direct sum M-dual holds.

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Pith. "Pith review of Quadratic spaces and Selmer groups of abelian varieties with multiplication." pith.science (2026). https://pith.science/paper/LOPSFW5B

@misc{pith2026250421272,
  author       = {Pith},
  title        = {Pith review of: Quadratic spaces and Selmer groups of abelian varieties with multiplication},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/LOPSFW5B}},
  note         = {Machine review of arXiv:2504.21272}
}
abstract

For certain symmetric isogeny $\lambda: A\rightarrow A^\vee$ of abelian varieties over a global field $F$, B. Poonen and E. Rains put an orthogonal quadratic structure on $\mathrm{H}^1(\mathbb{A}_F,A[\lambda])$ and realize the Selmer group $\mathrm{Sel}_\lambda(A)$ as an intersection of two maximal isotropic subspaces of $\mathrm{H}^1(\mathbb{A}_F,A[\lambda])$. With this understanding of Selmer groups, they expect to model the Selmer groups of elliptic curves and Jacobian varieties of hyperelliptic curves as the intersections of random maximal isotropic subspaces of orthogonal spaces. We extend this phenomenon to abelian varieties with multiplication and discuss the Shafarevich-Tate groups.

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Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Selmer ranks in twists of CM abelian varieties

    math.NT 2025-04 conditional novelty 7.0 of 10

    For CM abelian varieties satisfying a simplicity hypothesis, Selmer ranks in p-th twists obey the symplectic or unitary distribution D^epsilon_q, giving unsolvability of most twisted Fermat curves along a fan structure.

Reference graph

Works this paper leans on

74 extracted references · 67 canonical work pages · cited by 1 Pith paper

  1. [50]

    Poonen and E

    B. Poonen and E. Rains. Random maximal isotropic subspaces and Selmer groups.J. Amer. Math. Soc., 25(1), 2012

  2. [1]

    The Average Size of 2-Selmer Groups of Elliptic Curves in Characteristic 2

    N. Achenjang. The average size of 2-Selmer groups of elliptic curves in characteristic 2.arXiv:2310.08493v3, 2023

  3. [2]

    Amir-Khosravi

    Z. Amir-Khosravi. Serre’s tensor construction and moduli of abelian schemes.Manuscripta Math., 156:409– 456, 2018

  4. [3]

    G. E. Andrews.The theory of partion, volume 2 ofEncyclopedia of Mathematics and its Applications. Addison-Wesley, 1976. 42

  5. [4]

    M. F. Atiyah and C. T. C. Wall. Cohomology of groups. In J. W. S. Cassels and A. Fr¨ ohlich, editors,Algeraic Number Theory, Proc. of an Instructional Conference by L. M. S., chapter IV, pages 94–113. Harcourt Brace Jovanovich, 1967

  6. [5]

    Bak.K-theory of forms, volume 98 ofAnnals of Mathematics Studies

    A. Bak.K-theory of forms, volume 98 ofAnnals of Mathematics Studies. Princeton University Press, Prince- ton, NJ, 1981

  7. [6]

    Bhargava, D

    M. Bhargava, D. Kane, H. Lenstra, B. Poonen, and E. Rains. Modeling the distribution of ranks, Selmer groups, and Shafarevich-Tate groups of elliptic curves.Camb. J. Math., 3(3):275–321, 2015

  8. [7]

    Bhargava and A

    M. Bhargava and A. Shankar. The average number of elements in the 4-Selmer groups of elliptic curves is 7.arXiv:1312.7333, 2013

Show all 74 references
  1. [8]

    Bhargava and A

    M. Bhargava and A. Shankar. The average size of the 5-Selmer group of elliptic curves is 6, and the average rank is less than 1.arXiv:1312.7859, 2013

  2. [9]

    Bhargava and A

    M. Bhargava and A. Shankar. Binary quartic forms having bounded invariants, and the boundedness of the average rank of elliptic curves.Ann. of Math., 181:191–242, 2015

  3. [10]

    Bhargava and A

    M. Bhargava and A. Shankar. Ternary cubic forms having bounded invariants, and the existence of a positive proportion of elliptic curves having rank 0.Ann. of Math., 181:587–621, 2015

  4. [11]

    Bloch and K

    S. Bloch and K. Kato. L-functions and Tamagawa numbers of motives. In P. Cartier and et al., editors,The Grothendieck Festschrift I, volume 86 ofProgr. Math., pages 333–400. Birkhauser Boston, 1990

  5. [12]

    Bosch, W

    S. Bosch, W. L¨ utkebohmert, and M. Raynaud.N´ eron models, volume 21 ofErgebnisse der Mathematik und ihrer Grenzgebiete (3). Springer Berlin, Heidelberg, 1990

  6. [13]

    Bourbaki.Espaces vectoriels topologiques

    N. Bourbaki.Espaces vectoriels topologiques. Masson, Paris, 1981

  7. [14]

    T. J. I’a. Bromwich.An introduction to the theory of infinite series. Macmillan, London, 2nd edition revised edition, 1964

  8. [15]

    Casselman

    B. Casselman. local quadratic extensions.Notes available at https://personal.math. ubc.ca/ cass/research/ pdf/QuadraticCFT.pdf

  9. [16]

    J. W. S. Cassels. Arithmetic on curves of genus 1, IV. Proof of the hauptvermutung.J. Reine Angew. Math., 211, 1962

  10. [17]

    J. W. S. Cassels. Global fields. In J. W. S. Cassels and A. Fr¨ ohlich, editors,Algeraic Number Theory, Proc. of an Instructional Conference by L. M. S., chapter II, pages 42–84. Harcourt Brace Jovanovich, 1967

  11. [18]

    B. Conrad. Gross-Zagier revisited. InHeegner points and Rankin L-series, volume 49 ofMath. Sci. Res. Inst. Publ., pages 67–163. Cambridge University Press, 2004

  12. [19]

    A. J. de Jong. Counting elliptic surfaces over finite fields.Mosc. Math. J., 2(2):281–311, 2002

  13. [20]

    Deligne and G

    P. Deligne and G. Pappas. Singularit´ es des espaces de modules de Hilbert, en les caract´ ristiques divisant le discriminant.Compositio Mathematica, 90(1):59–79, 1994

  14. [21]

    Edixhoven, G

    B. Edixhoven, G. van der Geer, and B. Moonen.Abelian varieties. In preparation. Available at https:// gerard.vdgeer.net/AV.pdf

  15. [22]

    Ellenberg and A

    J. Ellenberg and A. Landesman. Homological stability for generalized Hurwitz spaces and Selmer groups in quadratic twist families over function fields.arXiv:2310.16286v3, 2023

  16. [23]

    Faltings

    G. Faltings. Finite theorems for abelian varieties over number fields. In G. Cornell and J. H. Silverman, editors,Arithmetic geometry, chapter II, pages 9–26. Springer New York, 1986

  17. [24]

    T. Feng, A. Landesman, and E. Rains. The geometric distribution of Selmer groups of elliptic curves over function fields.Math. Ann., 387:615–687, 2023

  18. [25]

    M. Flach. A generalization of Cassels-Tate pairing.J. Reine Angew. Math., 412(113-127), 1990

  19. [26]

    J. Flood. Pontryagin duality for topological modules.Proc. Amer. Math. Soc., 75(2):329–333, 1979

  20. [27]

    J. Fulman. Probability in the classical groups over finite fields.Ph. D. thesis, Harvard Univ., 1997

  21. [28]

    Fulman and L

    J. Fulman and L. Goldstein. Stein’s method and the rank distribution of random matrices over finite fields. The Annals of Probability, 43(3):1274–1314, 2015

  22. [29]

    Fulman and D

    J. Fulman and D. Stanton. On the distribution of the number of fixed vectors for the finite classical groups. Ann. Comb., 20:755–773, 2016

  23. [30]

    Grothendieck

    A. Grothendieck. ´El´ ements de g´ eom´ etrie alg´ ebrique: IV.´Etude locale des sch´ emas et des morphismes de sch´ emas. III., volume 28 ofPubl. Math. Inst. Hautes ´Etudes Sci.1966

  24. [31]

    Grothendieck

    A. Grothendieck. Le groupe de Brauer III. Exemples et compl´ ements. In A. Grothendieck and N. H. Kuiper, editors,Dix Expos´ es sur la Cohomologie des Sch´ emas, volume 3 ofAdvanced Studies in Pure Mathematics, pages 88–188. North-Holland, Amsterdam, 1968

  25. [32]

    D. R. Heath-Brown. The size of Selmer groups for the congruent number problem.Invent. Math., 111(1):171– 195, 1993

  26. [33]

    D. R. Heath-Brown. The size of Selmer groups for the congruent number problem. II. With an appendix by P. Monsky.Invent. Math., 118(2):331–370, 1994

  27. [34]

    Gerth III

    F. Gerth III. Limit probabilities for coranks of matrices overF q.Linear and Multilinear Algebra, 19:79–93, 1986

  28. [35]

    Kac and P

    V. Kac and P. Cheung.Quantum calculus. Universitext. Springer New York, 2001

  29. [36]

    D. Kane. On the ranks of the 2-Selmer groups of twists of a given elliptic curve.Algebra & Number Theory, 7(5):1253–1279, 2013. 43

  30. [37]

    Klagsbrun, B

    Z. Klagsbrun, B. Mazur, and K. Rubin. A Markov model for Selmer ranks in families of twists.Compositio Mathematica, 150(7):1077–1106., 2014

  31. [38]

    Knus.Quadratic and Hermitian forms over rings, volume 294 ofGrundlehren der Mathematischen Wissenschaften

    M.-A. Knus.Quadratic and Hermitian forms over rings, volume 294 ofGrundlehren der Mathematischen Wissenschaften. Springer, Berlin, Heidelberg, 1991

  32. [39]

    Koymans and A

    P. Koymans and A. Smith. Sums of rational cubes and the 3-Selmer group.arXiv:2405.09311, 2024

  33. [40]

    Maz and K

    B. Maz and K. Rubin. Ranks of twists of elliptic curves and hilbert’s tenth problem.Invent. Math., 181:541– 575, 2010

  34. [41]

    Mazur and K

    B. Mazur and K. Rubin. Finding large Selmer rank via an arithmetic theory of local constants.Ann. of Math., 166:579–612, 1994

  35. [42]

    J. S. Milne.Complex multiplication. Available at https://www.jmilne.org/math/CourseNotes/

  36. [43]

    J. S. Milne.Arithmetic duality theorems. Academic Press Inc Boston Ma, 2006

  37. [44]

    Mumford.Abelian varieties

    D. Mumford.Abelian varieties. Oxford University Press, London, 1974

  38. [45]

    Mumford, M

    D. Mumford, M. Nori, and P. Norman.Tata lecutres on theta, III, volume 97 ofProgr. Math.Birkhauser Boston, 1991

  39. [46]

    Pan and Y

    J. Pan and Y. Tian. On the distribution of 2-Selmer ranks of quadratic twists if elliptic curves overQ. arXiv:2503.21462, 2025

  40. [47]

    Polishchuk

    A. Polishchuk. Theta identities with complex multiplication.Duke Math. J., 96(2), 1999

  41. [48]

    Polishchuk.Abelian varieties, theta functions and the Fourier transform, volume 153 ofCambridge Tracts in Mathematics

    A. Polishchuk.Abelian varieties, theta functions and the Fourier transform, volume 153 ofCambridge Tracts in Mathematics. Cambridge University Press, 2003

  42. [49]

    Poonen and E

    B. Poonen and E. Rains. Self cup products and the theta characteristic torsor.Math. Res. Lett., 18(6):1305– 1318, 2011

  43. [51]

    Poonen and M

    B. Poonen and M. Stoll. The Cassels-Tate pairing on polarized abelian varieties.Ann. of Math., 150:1109– 1149, 1999

  44. [52]

    Ramakrishnan and R

    D. Ramakrishnan and R. J. Valenza.Fourier analysis on number fields, volume 186 ofGraduate Texts in Mathematics. Springer New York, 1998

  45. [53]

    Rapoport

    M. Rapoport. Compactifications de l’espace de modules de Hilbert-Blumenthal.Compositio Mathematica, 36(3):255–335, 1978

  46. [54]

    K. A. Ribet. Galois action on division points of abelian varieties with real multiplication.Amer. J. Math., 98(3), 1976

  47. [55]

    Scharlau.Quadratic and Hermitian forms, volume 270 ofGrundlehren der Mathematischen Wis- senschaften

    W. Scharlau.Quadratic and Hermitian forms, volume 270 ofGrundlehren der Mathematischen Wis- senschaften. Springer-Verlag, Berlin, 1985

  48. [56]

    J. P. Serre.Cohomologie Galisienne, volume 5 ofLecture Notes in Mathematics. Springer-Verlag, Berlin, 5th edition, 1994

  49. [57]

    Serre and J

    J.-P. Serre and J. Tate. Good reduction of abelian varieties.Ann. of Math., 68:492–517, 1968

  50. [58]

    Shatz.Profinite groups, arithmetic, and Geometry, volume 67 ofAnnals of Mathematics Studies

    S. Shatz.Profinite groups, arithmetic, and Geometry, volume 67 ofAnnals of Mathematics Studies. Princeton University Press, Princeton, NJ, 1972

  51. [59]

    J. Shu. Selmer ranks of twists of CM abelian varieties.arXiv:2504.21274, 2025

  52. [60]

    A. N. Skorobogatov. Abelian varieties over local and global fields.Notes available at https://www.ma.imperial.ac.uk/ anskor/abel%20var%20notes.pdf

  53. [61]

    A. Smith. The distribution ofℓ ∞-Selmer groups in degreeℓtwist families, I.arXiv:2207.05674v2., 2022

  54. [62]

    A. Smith. The Birch and Swinnerton-Dyer conjecture implies Goldfeld’s conjecture.arXiv:2503.17619, 2025

  55. [63]

    Swinnerton-Dyer

    P. Swinnerton-Dyer. The effect of twisting on the 2-Selmer group.Math. Proc. Cambridge Philos. Soc., 145(3):513–526, 2008

  56. [64]

    J. Tate. Duality theorems in Galois cohomology over number fields. InProc. Inter. Congr. Math., pages 234–241, Stockholm, 1962

  57. [65]

    J. Tate. WC-grous overp-adic fields.S´ eminaire Bourbaki, 4(156):265–277, 1995

  58. [66]

    D. L. Ulmer.p-descent in characteristicp.Duke Math. J., 62(2):237–265, 1991

  59. [67]

    van Dantzig

    D. van Dantzig. Zur topologischen algebra. III. Brouwersche und Cantorsche gruppen.Compositio Mathe- matica, 3:408–426, 1936

  60. [68]

    W. C. Waterhouse. Principal homogeneous spaces and group scheme extensions.Trans. Amer. Math. Soc., 153:181–189, 1971

  61. [69]

    Weil.Basic number theory, volume 144 ofGrundlehren der mathematischen Wissenschaften

    A. Weil.Basic number theory, volume 144 ofGrundlehren der mathematischen Wissenschaften. Springer Berlin, Heidelberg, third edition edition, 1974

  62. [70]

    G. Yu. Average size of 2-Selmer groups of elliptic curves, II.Acta Arith., 117(1):1–33, 2005

  63. [71]

    G. Yu. Average size of 2-Selmer groups of elliptic curves, I.Trans. Amer. Math. Soc., 358(4):1563–1584, 2006

  64. [72]

    Y. G. Zarhin. Noncommutative cohomology and Mumford groups.Mat. Zametki, 15:415–419, 1974

  65. [73]

    Y. G. Zarhin. Hyperelliptic Jacobians without complex multiplication.Math. Res. Lett., 7:123–132, 2000

  66. [74]

    Y. G. Zarhin. Hyperelliptic Jacobians without complex multiplication in positive characteristic.Math. Res. Lett., 8:429–435, 2001. 44 School of Mathematical Sciences, Tongji University, Shanghai 200092, P. R. China Email address:shujie@tongji.edu.cn 45

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