Unsolved Problems
Showing 1-13 of 13 problems
Sums of independent random variables with unbounded variance
Conjecture If $X_1, \dotsc, X_n \geq 0$ are independent random variables with $\mathbb{E}[X_i] \leq \mu$, then $$\mathrm{Pr} \left( \sum X_i - \mathbb...
P vs. NP
Problem Is P = NP?...
Exponential Algorithms for Knapsack
Conjecture The famous 0-1 Knapsack problem is: Given $a_{1},a_{2},\dots,a_{n}$ and $b$ integers, determine whether or not there are $0-1$ values $x_{...
The robustness of the tensor product
Problem Given two codes $R,C$, their Tensor Product $R \otimes C$ is the code that consists of the matrices whose rows are codewords of $R$ and whose ...
Subset-sums equality (pigeonhole version)
Problem Let $a_1,a_2,\ldots,a_n$ be natural numbers with $\sum_{i=1}^n a_i < 2^n - 1$. It follows from the pigeon-hole principle that there exist dist...
Complexity of square-root sum
Question What is the complexity of the following problem? Given $a_1,\dots,a_n; k$, determine whether or not $\sum_i \sqrt{a_i} \leq k.$...
Linear-size circuits for stable $0,1 < 2$ sorting?
Problem Can $O(n)$-size circuits compute the function $f$ on $\{0,1,2\}^*$ defined inductively by $f(\lambda) = \lambda$, $f(0x) = 0f(x)$, $f(1x) = 1f...
Discrete Logarithm Problem
If $p$ is prime and $g,h \in {\mathbb Z}_p^*$, we write $\log_g(h) = n$ if $n \in {\mathbb Z}$ satisfies $g^n = h$. The problem of finding such an int...
P vs. PSPACE
Problem Is there a problem that can be computed by a Turing machine in polynomial space and unbounded time but not in polynomial time? More formally, ...
One-way functions exist
Conjecture One-way functions exist....
Unconditional derandomization of Arthur-Merlin games
Problem Prove unconditionally that $\mathcal{AM}$ $\subseteq$ $\Sigma_2$....
P vs. BPP
Conjecture Can all problems that can be computed by a probabilistic Turing machine (with error probability < 1/3) in polynomial time be solved by a de...
Refuting random 3SAT-instances on $O(n)$ clauses (weak form)
Conjecture For every rational $\epsilon > 0$ and every rational $\Delta$, there is no polynomial-time algorithm for the following problem. Given is a...