{
  "annotation_id": "9cd9ef2f-a0cd-4302-b180-b030727e246e",
  "date_created": "2026-03-02T18:01:45.907000Z",
  "date_modified": "2026-03-02T18:01:45.907000Z",
  "file_hash": "aa51f46c10749add627ec147dc9e6150469fee602faf0f7afcec4f8462dd655b",
  "private": false,
  "record": {
    "abstract": "We prove new bounds on the quantum communication complexity of the\ndisjointness and equality problems. For the case of exact and non-deterministic\nprotocols we show that these complexities are all equal to n+1, the previous\nbest lower bound being n/2. We show this by improving a general bound for\nnon-deterministic protocols of de Wolf. We also give an O(sqrt{n}c^{log^*\nn})-qubit bounded-error protocol for disjointness, modifying and improving the\nearlier O(sqrt{n}log n) protocol of Buhrman, Cleve, and Wigderson, and prove an\nOmega(sqrt{n}) lower bound for a large class of protocols that includes the\nBCW-protocol as well as our new protocol.",
    "arxiv_id": "quant-ph/0109068",
    "authors": [
      "Peter Hoyer",
      "Ronald de Wolf"
    ],
    "categories": [
      "quant-ph",
      "cs.CC"
    ],
    "doi": "10.1007/3-540-45841-7_24",
    "journal_ref": "19th Annual Symposium on Theoretical Aspects of Computer Science,\n  STACS 2002, LNCS 2285, pp. 299-310, 2002",
    "title": "Improved Quantum Communication Complexity Bounds for Disjointness and   Equality",
    "url": "https://arxiv.org/abs/quant-ph/0109068"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "33a0754b-422e-4c15-aa73-cedc232340b1",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}