Editing Packing problems (section)

==Packing of irregular objects==
Packing of irregular objects is a problem not lending itself well to closed form solutions; however, the applicability to practical environmental science is quite important. For example, irregularly shaped soil particles pack differently as the sizes and shapes vary, leading to important outcomes for plant species to adapt root formations and to allow water movement in the soil.<ref>C.Michael Hogan. 2010. [http://www.eoearth.org/article/Abiotic_factor?topic=49461 ''Abiotic factor''. Encyclopedia of Earth. eds Emily Monosson and C. Cleveland. National Council for Science and the Environment]. Washington DC</ref>

The problem of deciding whether a given set of [[polygon]]s can fit in a given square container has been shown to be complete for the [[existential theory of the reals]].<ref>{{citation
 | last1 = Abrahamsen | first1 = Mikkel
 | last2 = Miltzow | first2 = Tillmann
 | last3 = Nadja | first3 = Seiferth
 | arxiv = 2004.07558
 | title = Framework for <math>\exists\mathbb{R}</math>-Completeness of Two-Dimensional Packing Problems
 | year = 2020}}.</ref>