{
  "abstract": "A ball bouncing on a thicker cushion should bounce less. We show that this is not always so . Measuring the coefficient of restitution $e$ of a steel ball dropped on a stack of $N$ sheets of standard A4 printer paper, we find that $e$ first drops, then rises to a pronounced maximum, and only then decreases towards a minimum. The maximum occurs where the acoustic round trip through the stack matches the contact time of the impact. For a contact set by the stack itself, one recovers the classical bar-impact condition of a stack-to-ball mass ratio of order one. Bar impact, however, predicts only a weak recovery, insensitive to the surrounding gas. For paper stacks, the recovery is large and no maximum is resolved when the stack is evacuated: the air trapped between the sheets, not the paper alone, makes the stack a trampoline.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.31213",
  "author_total": 5,
  "authors": [
    {
      "name": "Manou Liesker"
    },
    {
      "name": "Colton Kawamura"
    },
    {
      "name": "Maria Kieft"
    },
    {
      "name": "Joshua A. Dijksman"
    },
    {
      "name": "Antoine Deblais"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c0pamksvsknc9.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.31213",
  "fulltext_url": null,
  "id": "c0pamksvsknc9",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.31213",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.soft"
    ],
    [
      "openalex",
      "3109|Experimental and Theoretical Physics Studies"
    ]
  ],
  "openalex": "W7214636946",
  "pdf_url": "https://arxiv.org/pdf/2609.31213",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-25",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c0pamksvsknc9.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:52Z",
      "native_id": "2609.31213",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.31213"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.soft",
      "subfield": "condensed-matter"
    }
  ],
  "title": "The Paper-Stack Trampoline: Acoustic Restitution in Layered Media",
  "title_text": "The Paper-Stack Trampoline: Acoustic Restitution in Layered Media",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:52Z",
  "url": "https://research.draconitic.com/paper/c0pamksvsknc9",
  "venue": "arXiv",
  "versions": []
}