Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A New Protocol and Lower Bounds for Quantum Coin Flipping   We present a new protocol and two lower bounds for quantum coin flipping. In
our protocol, no dishonest party can achieve one outcome with probability more
than 0.75. Then, we show that our protocol is optimal for a certain type of
quantum protocols.
  For arbitrary quantum protocols, we show that if a protocol achieves a bias
of at most $\epsilon$, it must use at least $\Omega(\log \log
\frac{1}{\epsilon})$ rounds of communication. This implies that the parallel
repetition fails for quantum coin flipping. (The bias of a protocol cannot be
arbitrarily decreased by running several copies of it in parallel.)

6
The categories of this paper are: astro-ph
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg