{"abstract":[{"text":"The genus g(G) of a graph G is the minimum g such that G has an embedding on the orientable surface M_g of genus g. A drawing of a graph on a surface is independently even if every pair of nonadjacent edges in the drawing crosses an even number of times. The Z_2-genus of a graph G, denoted by g_0(G), is the minimum g such that G has an independently even drawing on M_g. By a result of Battle, Harary, Kodama and Youngs from 1962, the graph genus is additive over 2-connected blocks. In 2013, Schaefer and Stefankovic proved that the Z_2-genus of a graph is additive over 2-connected blocks as well, and asked whether this result can be extended to so-called 2-amalgamations, as an analogue of results by Decker, Glover, Huneke, and Stahl for the genus. We give the following partial answer. If G=G_1 cup G_2, G_1 and G_2 intersect in two vertices u and v, and G-u-v has k connected components (among which we count the edge uv if present), then |g_0(G)-(g_0(G_1)+g_0(G_2))|<=k+1. For complete bipartite graphs K_{m,n}, with n >= m >= 3, we prove that g_0(K_{m,n})/g(K_{m,n})=1-O(1/n). Similar results are proved also for the Euler Z_2-genus. We express the Z_2-genus of a graph using the minimum rank of partial symmetric matrices over Z_2; a problem that might be of independent interest. ","lang":"eng"}],"department":[{"_id":"UlWa"}],"publication_status":"published","date_published":"2019-06-01T00:00:00Z","date_updated":"2021-01-12T08:13:24Z","tmp":{"image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"article_processing_charge":"No","month":"06","day":"01","type":"conference","file":[{"file_id":"7445","file_size":628347,"date_created":"2020-02-04T09:14:31Z","date_updated":"2020-07-14T12:47:57Z","content_type":"application/pdf","access_level":"open_access","creator":"dernst","file_name":"2019_LIPIcs_Fulek.pdf","checksum":"aac37b09118cc0ab58cf77129e691f8c","relation":"main_file"}],"alternative_title":["LIPIcs"],"status":"public","title":"Z_2-Genus of graphs and minimum rank of partial symmetric matrices","quality_controlled":"1","scopus_import":1,"publisher":"Schloss Dagstuhl - Leibniz-Zentrum für Informatik","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","date_created":"2020-01-29T16:17:05Z","oa_version":"Published Version","oa":1,"article_number":"39","_id":"7401","language":[{"iso":"eng"}],"conference":{"end_date":"2019-06-21","location":"Portland, OR, United States","name":"SoCG: Symposium on Computational Geometry","start_date":"2019-06-18"},"citation":{"short":"R. Fulek, J. Kyncl, in:, 35th International Symposium on Computational Geometry (SoCG 2019), Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019.","ama":"Fulek R, Kyncl J. Z_2-Genus of graphs and minimum rank of partial symmetric matrices. In: <i>35th International Symposium on Computational Geometry (SoCG 2019)</i>. Vol 129. Schloss Dagstuhl - Leibniz-Zentrum für Informatik; 2019. doi:<a href=\"https://doi.org/10.4230/LIPICS.SOCG.2019.39\">10.4230/LIPICS.SOCG.2019.39</a>","ista":"Fulek R, Kyncl J. 2019. Z_2-Genus of graphs and minimum rank of partial symmetric matrices. 35th International Symposium on Computational Geometry (SoCG 2019). SoCG: Symposium on Computational Geometry, LIPIcs, vol. 129, 39.","apa":"Fulek, R., &#38; Kyncl, J. (2019). Z_2-Genus of graphs and minimum rank of partial symmetric matrices. In <i>35th International Symposium on Computational Geometry (SoCG 2019)</i> (Vol. 129). Portland, OR, United States: Schloss Dagstuhl - Leibniz-Zentrum für Informatik. <a href=\"https://doi.org/10.4230/LIPICS.SOCG.2019.39\">https://doi.org/10.4230/LIPICS.SOCG.2019.39</a>","chicago":"Fulek, Radoslav, and Jan Kyncl. “Z_2-Genus of Graphs and Minimum Rank of Partial Symmetric Matrices.” In <i>35th International Symposium on Computational Geometry (SoCG 2019)</i>, Vol. 129. Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019. <a href=\"https://doi.org/10.4230/LIPICS.SOCG.2019.39\">https://doi.org/10.4230/LIPICS.SOCG.2019.39</a>.","ieee":"R. Fulek and J. Kyncl, “Z_2-Genus of graphs and minimum rank of partial symmetric matrices,” in <i>35th International Symposium on Computational Geometry (SoCG 2019)</i>, Portland, OR, United States, 2019, vol. 129.","mla":"Fulek, Radoslav, and Jan Kyncl. “Z_2-Genus of Graphs and Minimum Rank of Partial Symmetric Matrices.” <i>35th International Symposium on Computational Geometry (SoCG 2019)</i>, vol. 129, 39, Schloss Dagstuhl - Leibniz-Zentrum für Informatik, 2019, doi:<a href=\"https://doi.org/10.4230/LIPICS.SOCG.2019.39\">10.4230/LIPICS.SOCG.2019.39</a>."},"publication_identifier":{"isbn":["978-3-95977-104-7"],"issn":["1868-8969"]},"external_id":{"arxiv":["1903.08637"]},"publication":"35th International Symposium on Computational Geometry (SoCG 2019)","author":[{"orcid":"0000-0001-8485-1774","full_name":"Fulek, Radoslav","id":"39F3FFE4-F248-11E8-B48F-1D18A9856A87","last_name":"Fulek","first_name":"Radoslav"},{"last_name":"Kyncl","first_name":"Jan","full_name":"Kyncl, Jan"}],"has_accepted_license":"1","doi":"10.4230/LIPICS.SOCG.2019.39","project":[{"call_identifier":"FWF","grant_number":"M02281","_id":"261FA626-B435-11E9-9278-68D0E5697425","name":"Eliminating intersections in drawings of graphs"}],"ddc":["000"],"file_date_updated":"2020-07-14T12:47:57Z","year":"2019","volume":129,"intvolume":"       129"}