Questions regarding the amount of communication needed to accomplish a computational task, when the information about the task is spread across several agents

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8
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1answer
254 views

Lower bound for NFA accepting 3 letter language

Related to a recent question (Bounds on the size of the smallest NFA for L_k-distinct) Noam Nisan asked for a method to give a better lower bound for the size of an NFA than what we get from ...
18
votes
1answer
196 views

Deterministic communication complexity vs partition number

Background: Consider the usual two-party model of communication complexity where Alice and Bob are given $n$-bit strings $x$ and $y$ and have to compute some Boolean function $f(x,y)$, where ...
9
votes
1answer
340 views

Best sources for communication complexity

What are some of the best sources (books and papers) to motivate and learn communication complexity on its own and in connection with its relation to computational complexity theory?
10
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1answer
132 views

Any evidence that Linial, Shraibman lower bound on quantum communication complexity is not tight?

As far as I know, the factorization norm lower bound given by Linial and Shraibman is essentially the only lower bound known for quantum communication complexity (or at least it subsumes all others). ...
6
votes
1answer
117 views

Zero error randomized communication complexity vs deterministic communication complexity

It is known that for $\Theta(1)$ error the worst case definition of randomized communication complexity and average case definition are equivalent. But when the error is $0$, the worst case randomized ...
18
votes
2answers
554 views

Bounds on the size of the smallest NFA for L_k-distinct

Consider the language $L_{k-distinct}$ consisting of all $k$-letter strings over $\Sigma$ such that no two letters are equal: $$ L_{k-distinct} :=\{w = \sigma_1\sigma_2...\sigma_k \mid \forall ...
7
votes
1answer
92 views

Lower bounds on alternative models of multiparty communication complexity

I'm a newcomer to communication complexity, and so far I've read the chapter in Arora-Barak and some papers giving lower bounds in various applications. A priori the definition of multiparty ...
7
votes
3answers
235 views

Communication complexity of finding common element of two subsets

Suppose that Alice receives a subset $S \subseteq \{1,\dots,n\}$ and Bob receives $T \subseteq \{1,\dots,n\}$. It is promised that $\lvert S \cap T \rvert = 1$. What is the randomized communication ...
1
vote
1answer
141 views

Succinct Representation and Communication complexity

Succinct representation is often used to define NEXP or EXP complete problems. For example, when a graph is given as a circuit to compute the existence of edge between vertex $i,j$ for indices of ...
0
votes
1answer
130 views

Various conjectures which is similar to Log Rank conjecture

Log rank conjecture is one of the most famous open problems in the area of communication compleixty. Lets consider the two party cdommunication complexity. Alice and Bob have $n$ bit strings $a,b$ , ...
2
votes
0answers
72 views

Are there efficient black-box constructions of sigma-protocols for SAT?

Is there a known black-box construction for the following implication? non-interactive string commitment that stretches additively by an amount which does not depend on the string being ...
6
votes
2answers
278 views

Testing for equality with zero error

This question comes from what I asked in a comment here, although I realized that I don't actually care about which input is less than the other, if they're different. Alice and Bob have n-bit ...
14
votes
2answers
569 views

Testing for positivity instead of equality

Alice and Bob have n-bit strings, and want to figure out if they're equal while doing little communication. The standard randomized solution is to treat the n-bit strings as polynomials of degree $n$ ...
10
votes
1answer
233 views

Why does the log-rank conjecture use rank over the reals?

In communication complexity, the log-rank conjecture states that $$cc(M) = (\log rk(M))^{O(1)}$$ Where $cc(M)$ is the communication complexity of $M(x,y)$ and $rk(M)$ is the rank of $M$ (as a ...
3
votes
0answers
195 views

Streaming Algorithm Lower Bounds by Communication Complexity

I am learning the methods for proving lower bounds on streaming algorithms using communication complexity. My question is about a basic technique to prove lower bounds on streaming models using the ...
1
vote
1answer
206 views

“Send Once”-One way Multiparty Communication Complexity

There are plenty results on multiparty communication complexity, and one way protocol which anyone playing communicatin games is able to send one person, is a basic setting. I want to consider more ...
4
votes
1answer
298 views

Streaming Algorithms: Motivations for estimating frequency moments

The celebrated AMS paper "The space complexity of approximating the frequency moments" defines the problem as following: Let $a_1, a_2,\dotsc, a_m$ be a sequence of integers where each $a_j \in ...
12
votes
1answer
229 views

Best communication complexity lower bound of disjointness

It is well known that no deterministic two-party protocol can solve disjointness problem (DISJ) on $n$-bit inputs without sending n+1 bits in the worst case (see, e.g., the book by Kushilevitz and ...
7
votes
2answers
165 views

Delegating all of the work to the prover in $\mathcal{MA}$ protocols

An $\mathcal{MA}$ communication complexity protocol is communication complexity protocol that starts with an omniscient prover that sends a proof (that depends on the the specific input of the ...
7
votes
0answers
135 views

Communication complexity of random functions with limited independence

Let $X_0, \ldots, X_{2^n-1}$ be $k$-wise independent random $0/1$ variables over a sample space $\Omega$ and $Prob \left[ X_i = 1 \right] = p$ for every $i$ and some $0 < p < 1$. Let assume $n$ ...
8
votes
1answer
229 views

A balanced generalization of Hall’s theorem

Let $X$ and $Y$ be sets, and $\mathcal{B}$ be a partition of $X \times Y$. I would like to prove that there exists a distribution $\mathcal{D}$ over $X \times Y$ whose marginal is uniform over $X$, ...
3
votes
0answers
132 views

Lower Bound Methods in NonDet Communication Complexity

rank+($M$) is the minimum $r$ such that the following statement holds. The statement : there exists matrices $U,V$ such that $M = UV$ and $U$ has $r$ columns and $V$ has $r$ rows. Is rank+($M$) ...
5
votes
1answer
196 views

Average message complexity for the election problem on graphs

I am currently studying the election problem in distributed algorithms. There, I stumpled over one approach to implement a Chang-Roberts-like message extinction algorithm on graphs without requiring a ...
4
votes
0answers
170 views

Do the quantum communication complexity lower bounds hold when parties can send a “duplicated” qubits?

This question continues from the previous question where I mistakenly asked a question that is too general. In quantum communication complexity, we always assume that Alice and Bob have unlimited ...
0
votes
2answers
301 views

Are Alice and Bob allowed to copy qubits in quantum communication complexity model?

In quantum communication complexity, we always assume that Alice and Bob have unlimited computational power and are still prove lower bounds such as the $\Omega(n)$ lower bounds of parity. What ...
12
votes
0answers
382 views

Known upper bounds on the communication complexity of Karchmer-Wigderson games

In 1988 Karchmer and Wigderson established a nice characterization of the circuit depth $d$ (DeMorgan circuits) of a Boolean function $f \colon \{0,1\}^n\rightarrow\{0,1\}$: $d$ is exactly the number ...
9
votes
3answers
223 views

Bounds on approximating frequency moments

Let $a_1, a_2,\dotsc, a_m$ be a sequence of integers where each $a_j \in \{1,2,\dotsc,n\}$. For $i \in \{1,2,\dotsc,n\}$, let $m_i = |\{j : a_j = i\}|$. The $k$th frequency moment is defined to be ...
8
votes
2answers
470 views

Communication complexity with a referee

Assume a framework in communication complexity where we have two players A(lice) and B(ob) and a R(eferee). A and B don't communicate directly with each other. In each round of communication, each of ...
17
votes
0answers
283 views

Descriptive complexity of communication complexity classes

It is well known that some major complexity classes, like P or NP, admit a full logical characterization (e.g NP = existential 2nd order logic by Fagin's theorem). On the other hand, one can also ...
10
votes
2answers
340 views

Nonlocal Games and Quantum Communication

I'm currently on the look out for some good reference material relating non-local games with beneficial aspects in quantum communication. For instance, I am aware that non-local games are good at ...
7
votes
1answer
84 views

Effect of protocol ordering on multiparty comm. complexity

Brief Background In Multi-Party Protocols by Chandra, Lipton, and Furst [CFL83], a Ramsey-theoretic proof is used to show a lower bound (and later, a matching upper bound) for the predicate ...
4
votes
1answer
371 views

Monochromatic Rectangle Tiling

This problem originates from the tiling lowerbound method for communication complexity. In that method, there is a 0-1 matrix $M_{n \times n}$. A rectangle is defined as a submatrix $A \times B$ where ...
6
votes
1answer
519 views

Existence of zero-knowledge proof for location

N items have been placed at specific points on a map. A prize is awarded to the first person who turns in a list with the location of all N items. The location of each item must fall with a distance ...
10
votes
1answer
241 views

What is the largest gap between rank and approximate rank?

We know that the log of the rank of a 0-1 matrix is the lower bound of deterministic communication complexity, and the log of the approximate rank is the lower bound of randomized communication ...
4
votes
1answer
163 views

Why does deterministic recognition of DYCK(2) languages in the streaming model take linear space?

I was reading the paper "Recognizing Well-Paranthesized Expressions in the Streaming Model" by Magniez, Mathieu and Nayak where they give upper and lower bounds on the space required to recognize ...
11
votes
2answers
630 views

Best alien communication protocol?

Let's say we discover alien civilizations that are able to send and receive messages using an interstellar digital communications channel. (Say using modulated radio waves, laser pulses, ...
8
votes
2answers
333 views

Finding out a set by intersection comparison

The following problem recently emerged from my research and I would like to ask if anyone knows if this problem was considered before or has heard of anything that might be related. The general ...
8
votes
3answers
456 views

One way randomised communication complexity of disjointness

I am looking for a reference for the (classical) one way randomised communication complexity of disjointness when the universe can be large. Say Alice and Bob both have sets of size $m$ chosen from a ...
22
votes
2answers
933 views

Protocol partition number and deterministic communication complexity

Besides (deterministic) communication complexity $cc(R)$ of a relation $R$, another basic measure for the amount of communication needed is the protocol partition number $pp(R)$. The relation between ...
16
votes
4answers
748 views

Communication Complexity …Classes?

Discussion: I've been spending some personal time lately learning various things in communication complexity. For instance, I've re-familiarized myself with the relevant chapter in Arora/Barak, ...
5
votes
1answer
265 views

Stronger Lower Bounds on Nondeterministic Multiparty Communication

This is a continuation of my previous question on Lower bounds for Nondeterministic Multiparty Communication. From the answer, the $\mu^\infty$ norm lower bounds nondeterministic multiparty ...
11
votes
1answer
389 views

Lower bounds for Nondeterministic Multiparty Communication

This is a continuation of my previous question on communication lower bounds for partial boolean functions. Can someone suggest any reference on lower bounds for nondeterministic multiparty ...
6
votes
2answers
337 views

Communication lower bounds for partial boolean functions

There are well known techniques for proving lower bounds on the communication complexity of boolean functions, like fooling sets, the rank of the communication matrix, and discepancy. 1) How do we ...
12
votes
2answers
331 views

multi-party Communication complexity of “Set Partition problem”

In an application I'm considering, I need to know the communication complexity of the following problem: Given $n$, let $S$ be the set of integers from $1$ to $n$. Alice, Bob, and Carol each ...
10
votes
1answer
672 views

Communication complexity for deciding associativity

Let $S=${$0,...,n-1$} and $\circ : S \times S \rightarrow S$. I want to compute the communication complexity of deciding whether $\circ$ is associative. The model is the following. $\circ$ is given ...
18
votes
1answer
393 views

Approximating the sign rank of a matrix

The sign rank of a matrix A with +1,-1 entries is the least rank (over the reals) of a matrix B which has the same sign pattern as A (i.e., $A_{ij}B_{ij}>0$ for all $i,j$). This notion is important in ...