{"abstract":[{"lang":"eng","text":"We introduce extension-based proofs, a class of impossibility proofs that includes valency arguments. They are modelled as an interaction between a prover and a protocol. Using proofs based on combinatorial topology, it has been shown that it is impossible to deterministically solve k-set agreement among n > k ≥ 2 processes in a wait-free manner. However, it was unknown whether proofs based on simpler techniques were possible. We explain why this impossibility result cannot be obtained by an extension-based proof and, hence, extension-based proofs are limited in power."}],"date_published":"2020-07-31T00:00:00Z","date_created":"2020-09-13T22:01:18Z","publication_identifier":{"isbn":["9781450375825"]},"page":"54-56","conference":{"location":"Virtual, Italy","end_date":"2020-08-07","start_date":"2020-08-03","name":"PODC: Principles of Distributed Computing"},"date_updated":"2024-02-28T12:54:19Z","doi":"10.1145/3382734.3405743","title":"Brief Announcement: Why Extension-Based Proofs Fail","department":[{"_id":"DaAl"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","quality_controlled":"1","oa_version":"None","language":[{"iso":"eng"}],"author":[{"orcid":"0000-0003-3650-940X","id":"4A899BFC-F248-11E8-B48F-1D18A9856A87","last_name":"Alistarh","first_name":"Dan-Adrian","full_name":"Alistarh, Dan-Adrian"},{"first_name":"James","full_name":"Aspnes, James","last_name":"Aspnes"},{"last_name":"Ellen","first_name":"Faith","full_name":"Ellen, Faith"},{"last_name":"Gelashvili","full_name":"Gelashvili, Rati","first_name":"Rati"},{"first_name":"Leqi","full_name":"Zhu, Leqi","last_name":"Zhu"}],"month":"07","article_processing_charge":"No","publication_status":"published","publisher":"Association for Computing Machinery","type":"conference","citation":{"mla":"Alistarh, Dan-Adrian, et al. “Brief Announcement: Why Extension-Based Proofs Fail.” <i>Proceedings of the 39th Symposium on Principles of Distributed Computing</i>, Association for Computing Machinery, 2020, pp. 54–56, doi:<a href=\"https://doi.org/10.1145/3382734.3405743\">10.1145/3382734.3405743</a>.","ama":"Alistarh D-A, Aspnes J, Ellen F, Gelashvili R, Zhu L. Brief Announcement: Why Extension-Based Proofs Fail. In: <i>Proceedings of the 39th Symposium on Principles of Distributed Computing</i>. Association for Computing Machinery; 2020:54-56. doi:<a href=\"https://doi.org/10.1145/3382734.3405743\">10.1145/3382734.3405743</a>","short":"D.-A. Alistarh, J. Aspnes, F. Ellen, R. Gelashvili, L. Zhu, in:, Proceedings of the 39th Symposium on Principles of Distributed Computing, Association for Computing Machinery, 2020, pp. 54–56.","chicago":"Alistarh, Dan-Adrian, James Aspnes, Faith Ellen, Rati Gelashvili, and Leqi Zhu. “Brief Announcement: Why Extension-Based Proofs Fail.” In <i>Proceedings of the 39th Symposium on Principles of Distributed Computing</i>, 54–56. Association for Computing Machinery, 2020. <a href=\"https://doi.org/10.1145/3382734.3405743\">https://doi.org/10.1145/3382734.3405743</a>.","ista":"Alistarh D-A, Aspnes J, Ellen F, Gelashvili R, Zhu L. 2020. Brief Announcement: Why Extension-Based Proofs Fail. Proceedings of the 39th Symposium on Principles of Distributed Computing. PODC: Principles of Distributed Computing, 54–56.","apa":"Alistarh, D.-A., Aspnes, J., Ellen, F., Gelashvili, R., &#38; Zhu, L. (2020). Brief Announcement: Why Extension-Based Proofs Fail. In <i>Proceedings of the 39th Symposium on Principles of Distributed Computing</i> (pp. 54–56). Virtual, Italy: Association for Computing Machinery. <a href=\"https://doi.org/10.1145/3382734.3405743\">https://doi.org/10.1145/3382734.3405743</a>","ieee":"D.-A. Alistarh, J. Aspnes, F. Ellen, R. Gelashvili, and L. Zhu, “Brief Announcement: Why Extension-Based Proofs Fail,” in <i>Proceedings of the 39th Symposium on Principles of Distributed Computing</i>, Virtual, Italy, 2020, pp. 54–56."},"scopus_import":"1","day":"31","year":"2020","status":"public","publication":"Proceedings of the 39th Symposium on Principles of Distributed Computing","_id":"8383"}