1,223 research outputs found
The distribution of the variance of primes in arithmetic progressions
Hooley conjectured that the variance V(x;q) of the distribution of primes up
to x in the arithmetic progressions modulo q is asymptotically x log q, in some
unspecified range of q\leq x. On average over 1\leq q \leq Q, this conjecture
is known unconditionally in the range x/(log x)^A \leq Q \leq x; this last
range can be improved to x^{\frac 12+\epsilon} \leq Q \leq x under the
Generalized Riemann Hypothesis (GRH). We argue that Hooley's conjecture should
hold down to (loglog x)^{1+o(1)} \leq q \leq x for all values of q, and that
this range is best possible. We show under GRH and a linear independence
hypothesis on the zeros of Dirichlet L-functions that for moderate values of q,
\phi(q)e^{-y}V(e^y;q) has the same distribution as that of a certain random
variable of mean asymptotically \phi(q) log q and of variance asymptotically
2\phi(q)(log q)^2. Our estimates on the large deviations of this random
variable allow us to predict the range of validity of Hooley's Conjecture.Comment: 26 pages; Modified Definition 2.1, the error term for the variance in
Theorem 1.2 and its proo
Residue classes containing an unexpected number of primes
We fix a non-zero integer and consider arithmetic progressions , with varying over a given range. We show that for certain specific
values of , the arithmetic progressions contain, on average,
significantly fewer primes than expected.Comment: 18 pages. Added a few remarks, changed the numbering of sections,
slightly improved results, and made a few correction
A conditional determination of the average rank of elliptic curves
Under a hypothesis which is slightly stronger than the Riemann Hypothesis for
elliptic curve -functions, we show that both the average analytic rank and
the average algebraic rank of elliptic curves in families of quadratic twists
are exactly . As a corollary we obtain that under this last
hypothesis, the Birch and Swinnerton-Dyer Conjecture holds for almost all
curves in our family, and that asymptotically one half of these curves have
algebraic rank , and the remaining half . We also prove an analogous
result in the family of all elliptic curves. A way to interpret our results is
to say that nonreal zeros of elliptic curve -functions in a family have a
direct influence on the average rank in this family. Results of Katz-Sarnak and
of Young constitute a major ingredient in the proofs.Comment: 27 page
Teachers' Burnout Profile- Risk and protective factors
Background: Burnout syndrome represents a factual risk for school teachers during their career. Several factors have been analyzed as stress sources enabled to menace teachers’ general well-being; nevertheless, protective factors mostly related to their personal resources may differently characterize teachers’ profiles. Objectives: The current study aimed to define different teachers’ profiles based on their burnout levels and attitudes towards job (i.e., job satisfaction, self-efficacy, attitudes toward professional growth, collective efficacy, positive and negative emotions, and hedonic balance). attitudes towards job Methods: Participants were 266 school teachers (F=69.1%) ranging from 26 to 65 years old (M=48.95; SD=8.31), with teaching experience ranged from 1 to 41 years (M=21.72; SD=10.36). Data were collected by three self-report questionnaires: Copenhagen Burnout Inventory, Attitudes towards job questionnaires, School Collective efficacy. Results: Cluster analysis approach showed two distinct teacher’s profiles named at-risk and non at-risk teachers. Main differences were due to burnout levels, attitudes toward job and extra-mansions at work. No differences were found related to teachers’ socio-demographic characteristics and their years of experience. Conclusions: The two teachers’ profiles resulting from the cluster analysis show several similarities, including collective efficacy and job satisfaction levels. Results are discussed in relation as to how teachers’ positive emotions towards their job can work as protective factors against the risk of burnou
Low-lying zeros of elliptic curve L-functions: Beyond the ratios conjecture
We study the low-lying zeros of L-functions attached to quadratic twists of a
given elliptic curve E defined over . We are primarily interested in
the family of all twists coprime to the conductor of E and compute a very
precise expression for the corresponding 1-level density. In particular, for
test functions whose Fourier transforms have sufficiently restricted support,
we are able to compute the 1-level density up to an error term that is
significantly sharper than the square-root error term predicted by the
L-functions Ratios Conjecture.Comment: 33 page
Low-lying zeros of quadratic Dirichlet -functions: A transition in the Ratios Conjecture
We study the -level density of low-lying zeros of quadratic Dirichlet
-functions by applying the -functions Ratios Conjecture. We observe a
transition in the main term as was predicted by the Katz-Sarnak heuristic as
well as in the lower order terms when the support of the Fourier transform of
the corresponding test function reaches the point . Our results are
consistent with those obtained in previous work under GRH and are furthermore
analogous to results of Rudnick in the function field case.Comment: 15 page
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