Chowla's Non-Vanishing Conjecture
- Chowla’s Non-Vanishing Conjecture consists of multiple related but mathematically distinct statements, each with specific scopes and implications.
- Examples are THE central-value formulation on quadratic Dirichlet characters predicting zero exclusion, the shifted-correlation conjecture involving lioville Function correlations, and the Chowla–Milnor conjecture regarding Hurwitz zeta.
- Chowla’s Non-Vanishing Conjecture encompasses ideas from analytic number theory, randomness and distributions sequences, as well as number theory over function fields. It includes applying a broad set of analytical tools and combinatorial techniques.
Chowla’s non-vanishing conjecture is an ambiguous designation for several conjectures associated with mathematician Sarvadaman Chowla. In analytic number theory, it most commonly denotes the assertion that central values of quadratic Dirichlet -functions do not vanish: for every primitive quadratic character over . In other contexts, “Chowla conjecture” denotes vanishing of correlations of shifted Liouville or Möbius functions, while the Chowla–Milnor conjecture concerns linear independence of Hurwitz zeta values. Chowla also formulated a cosine-sum problem predicting a negative minimum of order the square root of the cardinality of a finite set. These statements are mathematically distinct, and “non-vanishing” should not be used without specifying which object is asserted not to vanish.
1. Terminological scope and principal formulations
The central-value formulation of Chowla’s conjecture concerns real, nonprincipal Dirichlet characters. For a primitive quadratic character associated with a fundamental discriminant , it predicts
and in particular
The conjecture therefore asserts the complete absence of central-point zeros among quadratic Dirichlet -functions over (Li, 2018).
This statement is different from the shifted-correlation conjecture usually called Chowla’s conjecture. If 0 is the Liouville function, then for fixed distinct shifts 1,
2
The conclusion is cancellation, or normalized vanishing, rather than non-vanishing. The case 3 follows from the prime number theorem, while every fixed tuple with 4 remains open (Matomäki et al., 2015).
The phrase “Chowla’s non-vanishing conjecture” can consequently refer to at least four different subjects:
- Central 5-value non-vanishing for quadratic Dirichlet characters.
- Correlation cancellation for shifted Liouville or Möbius functions.
- The Chowla–Milnor conjecture on linear independence of rational Hurwitz zeta values.
- Chowla’s cosine problem, concerning quantitative negativity of finite cosine sums.
The shifted-correlation conjecture is sometimes informally associated with non-vanishing because it predicts that all finite sign patterns occur with positive density. Nevertheless, its standard mathematical formulation asserts that nontrivial correlations vanish.
2. Quadratic Dirichlet 6-functions over 7
For a primitive quadratic character 8, the completed 9-function satisfies a functional equation
0
For a real primitive quadratic character, 1, and the quadratic root number is 2 in the standard normalization. Hence the functional equation does not force
3
Chowla’s conjecture predicts that no accidental central zeros occur.
The conjecture remains open. Soundararajan proved that at least 4 of odd squarefree positive integers 5 satisfy
6
but a positive-density result does not establish non-vanishing for every quadratic character (Li, 2018).
A conditional approach uses a Landau–Siegel zero. Suppose a primitive quadratic character 7 modulo 8 has a real zero
9
For
0
a recent result proves, for 1 and
2
the conditional estimate
3
where 4 and the shifts are fixed (Jaskari et al., 2024). The mechanism is that the exceptional character resembles 5 on many primes while retaining periodicity and access to character-sum cancellation. A modified completely multiplicative function 6, agreeing with 7 on primes up to 8 and with 9 above 0, approximates 1 sufficiently well for a smooth–rough decomposition and a beta-sieve reduction to character sums.
This result is conditional and range-restricted. It does not prove the full fixed-shift Chowla conjecture, nor does it produce a lower bound showing that the correlations are nonzero. Its conclusion is an upper bound toward cancellation.
3. Function-field analogues
The rational-number conjecture has two contrasting function-field analogues.
For quadratic characters over 2, central vanishing can occur infinitely often. If 3 is monic and squarefree, the hyperelliptic curve
4
has an associated quadratic character 5. The condition
6
is equivalent to the occurrence of a prescribed Frobenius eigenvalue on the Jacobian 7, and also to the existence of a nonconstant map from 8 to a fixed abelian variety 9 (Li, 2018). Geometric constructions of such maps give infinitely many central zeros, with lower bounds of the forms
0
depending on the finite field.
Thus universal non-vanishing is false over 1, even though the rational-number conjecture predicts universal non-vanishing.
A statistical function-field analogue asks whether the proportion of nonvanishing central values tends to 2 as the genus grows. For 3, an unconditional theorem proves that the number of squarefree 4 of odd degree 5 with
6
is at most
7
Since the number of squarefree polynomials of degree 8 is of order 9, the proportion of vanishing values is 0. Consequently,
1
where 2 denotes the proportion of squarefree degree-3 polynomials whose quadratic characters have nonzero central value (Koymans et al., 10 Sep 2026).
The proof uses 4-adic Selmer-type spaces, Artin pairings, Rédei matrices, expansion maps, Rédei symbols, quartic reciprocity, function-field large-sieve estimates, and repeated Cauchy–Schwarz. The dimensions of non-systematic components of the Selmer spaces form a descending process; generic descent forces these components to vanish, which implies central non-vanishing.
The result is density one, not universal non-vanishing. Central zeros still occur infinitely often. Its scope is restricted to quadratic characters, odd-degree imaginary characters, 5, and the central point.
4. Chowla’s shifted-correlation conjecture
The Liouville function is completely multiplicative: 6 Chowla’s correlation conjecture states that for every fixed 7 and every tuple of distinct shifts,
8
The distinctness condition excludes repetitions such as 9.
The conjecture is equivalent to Bernoulli randomness of the Liouville sequence in the finite-dimensional correlation sense. Since the values are 0, vanishing of all nonempty shifted products implies that every sign pattern
1
has density 2. This is a normality or Bernoulli formulation, but it remains unproved for fixed shifts when L\!\left(\frac12,\chi_d\right)\neq0.$3 and $L\!\left(\frac12,\chi_d\right)\neq0.$4,
$L\!\left(\frac12,\chi_d\right)\neq0.$5
Thus the average absolute correlation is $L\!\left(\frac12,\chi_d\right)\neq0.$6 whenever $L\!\left(\frac12,\chi_d\right)\neq0.$7, but the result permits exceptional shift tuples and does not prove the conjecture for any prescribed fixed tuple (Matomäki et al., 2015).
The analytic method uses typical prime factorization, Ramaré’s identity, short-interval mean values for non-pretentious multiplicative functions, and a Kátai–Bourgain–Sarnak–Ziegler minor-arc argument. It also yields uniform averaged short-interval exponential-sum bounds
$L\!\left(\frac12,\chi_d\right)\neq0.$8
Ergodic theory provides another conditional route. If the Liouville sequence is generic for an ergodic Furstenberg system, then it is generic for the Bernoulli measure, and the Chowla correlations follow. The proof combines local Gowers-uniformity seminorms, inverse theorems involving nilsequences, nilsequence orthogonality, and Tao’s entropy-decrement reduction (Frantzikinakis, 2016). Ergodicity of the Liouville system itself remains unknown.
There are also subsequential counterpoint phenomena. Certain completely multiplicative, totally aperiodic functions constructed by Matomäki, Radziwiłł, and Tao fail the full-sequence Chowla conclusion: their two-point correlations need not converge to zero. Nevertheless, they possess subsequences whose Furstenberg systems are Bernoulli, as well as subsequences giving unipotent systems with finite-dimensional independence but higher-order algebraic dependence (Gomilko et al., 2020). This shows that subsequential Chowla behavior does not imply full-sequence Chowla behavior.
5. Other Chowla conjectures and non-vanishing interpretations
The Chowla–Milnor conjecture concerns the rational Hurwitz zeta values
$L\!\left(\frac12,\chi_d\right)\neq0.$9
It predicts that these $L$0 values are linearly independent over $L$1. Writing
$L$2
the difficult component is the odd space
$L$3
A 2025 result proves
$L$4
for fixed $L$5 as $q\to\infty (Lai et al., 19 May 2025). This establishes that at least logarithmically many odd combinations are nonzero and participate in rational linear independence, but it does not prove that every individual value is nonzero or that the full Chowla–Milnor conjecture holds.
Chowla’s cosine problem is a separate harmonic-analysis conjecture. For a finite set 6, define
7
Chowla conjectured
8
A recent result proves the first polynomial lower bound: 9 The proof embeds 0 into a cyclic Cayley graph, identifies cosine values with graph eigenvalues, and shows that a graph with a very small negative eigenvalue must contain a large clique, which is impossible for the relevant cyclic graph (Jin et al., 3 Sep 2025). The exponent 1 does not reach the conjectured 2.
The term “non-vanishing” also appears in the Ankeny–Artin–Chowla conjecture. For a prime 3, write the fundamental unit of 4 as
5
The conjecture asserted that 6. A counterexample is
7
for which 8 (Reinhart, 2024). This is a Pell-type non-divisibility assertion and is unrelated to shifted Liouville correlations or quadratic Dirichlet central values, although it belongs to the broader arithmetic network involving units, regulators, class numbers, and special 9-values.
6. Related extensions and current status
Chowla-type cancellation has been established in several settings that do not resolve the original fixed-shift conjecture.
Over 00, geometric methods prove the full fixed-order Möbius correlation conjecture under a finite-field size condition. If 01 with 02 odd and
03
then for distinct shifts 04,
05
with a power-saving estimate (Sawin et al., 2018). The proof exploits the characteristic-06 identity
07
which allows Möbius values on derivative fibers to be represented by quadratic Dirichlet characters. Improved function-field Burgess bounds and a level of distribution close to 08 then yield cancellation.
For Beatty sequences, if 09 is irrational, then
10
The higher-order Beatty analogue is only partially established: for 11, current results exclude correlations of essentially maximal size but do not prove convergence to zero (Teräväinen et al., 2023).
For a Steinhaus random multiplicative function 12, nonlinear polynomial sequences exhibit a different probabilistic form of cancellation. If 13 has degree at least 14 and is not of the form
15
then
16
If 17 is not a product of linear factors over 18, then almost surely there are arbitrarily large 19 such that
20
These are random-model results, not theorems for the deterministic Liouville function (Klurman et al., 2022).
The current status can therefore be summarized as follows:
- Quadratic Dirichlet central values over 21: universal non-vanishing remains open.
- Function-field quadratic central values: universal non-vanishing is false, but density-one non-vanishing holds for odd-degree imaginary characters when 22.
- Fixed-shift Liouville correlations: the full Chowla conjecture remains open for every fixed tuple with L\!\left(\frac12,\chi_d\right)\neq 0$23-value, a shifted multiplicative correlation, a Hurwitz-zeta linear relation, a cosine sum, or a Pell-type unit coefficient.
References (12)2.12.