TITLE: Is there a stronger (but widely believed) version of the Chowla conjecture?
QUESTION [7 upvotes]: In Terry Tao's notes on the Chowla conjecture, the said conjecture states that for any fixed integer $m>0$ and nonzero $(a_1,\ldots,a_m)\in\{0,1\}^m$, 
$$
\lim_{x\rightarrow\infty}\frac{1}{x}\sum_{n\leq x}\mu(n+1)^{a_1}\cdots\mu(n+m)^{a_m}=0,
$$
where $\mu$ denotes the Möbius function.  I would like information about the rate of this conjectured convergence.  Are there any widely believed conjectures along these lines?

REPLY [11 votes]: I imagine the "correct" conjecture is the Möbius $s$-tuples conjecture in the form that if $s \in \mathbb{N}$, $\alpha_1, \ldots, \alpha_s \in \mathbb{N}$ with at least one $\alpha_i$ odd, and $d_1, \ldots, d_s \in \mathbb{Z}$ distinct, then for all $\varepsilon > 0$ we have that
$$\sum_{n \leq x}{\mu(n + d_1)^{\alpha_1} \mu(n + d_2)^{\alpha_2} \cdots \mu(n + d_s)^{\alpha_s}} \ll_{\varepsilon} x^{1/2 + \varepsilon}$$
uniformly for all $|d_i| \leq x$. However, I don't imagine there is any good evidence for this other than the fact that the Riemann hypothesis implies the case $s = 1$. I don't think this problem has really been studied enough for there to be a widely-believed generalisation of Chowla's conjecture.
A form of this conjecture is assumed by Ng in this paper on the distribution of the Möbius function in short intervals; he assumes that this conjecture holds with "for all $\varepsilon > 0$" replaced by "for some $0 < \beta_0 < 1/2$".