Burkhardt quartic

In mathematics, the Burkhardt quartic is a quartic threefold in 4-dimensional projective space studied by {{harvs |txt |authorlink=Heinrich Burkhardt |last=Burkhardt |year1=1890 |year2=1891 |year3=1892}},

with the maximum possible number of 45 nodes.

Definition

The equations defining the Burkhardt quartic become simpler if it is embedded in P5 rather than P4.

In this case it can be defined by the equations σ1 = σ4 = 0, where σi is the ith elementary symmetric function of the coordinates (x0 : x1 : x2 : x3 : x4 : x5) of P5.

Properties

The automorphism group of the Burkhardt quartic is the Burkhardt group U4(2) = PSp4(3), a simple group of order 25920, which is isomorphic to a subgroup of index 2 in the Weyl group of E6.

The Burkhardt quartic is rational and furthermore birationally equivalent to a compactification of the Siegel modular variety A2(3).{{cite journal|title=The Geometry of Siegel Modular Varieties |last1=Hulek |first1=Klaus |last2=Sankaran |first2=G. K. |journal=Advanced Studies in Pure Mathematics |volume=35 |year=2002 |pages=89–156}}

References

{{Reflist}}

  • {{Citation | last1=Burkhardt | first1=Heinrich | title=Untersuchungen aus dem Gebiete der hyperelliptischen Modulfunctionen Erster Theil | doi=10.1007/BF01206368 | year=1890 | journal=Mathematische Annalen | volume=36 | issue=3 | pages=371–434 | url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN00225252X&L=1 | archive-url=https://archive.today/20130912062926/http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN00225252X&L=1 | url-status=dead | archive-date=September 12, 2013 }}
  • {{Citation | last1=Burkhardt | first1=Heinrich | title=Untersuchungen aus dem Gebiete der hyperelliptischen Modulfunctionen Zweiter Theil | publisher=Springer | doi=10.1007/BF01199251 | year=1891 | journal=Mathematische Annalen | volume=38 | issue=2 | pages=161–224 | url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002252996&L=1 | access-date=2013-09-12 | archive-url=https://web.archive.org/web/20160305080542/http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002252996&L=1 | archive-date=2016-03-05 | url-status=dead | url-access=subscription }}
  • {{Citation | last1=Burkhardt | first1=Heinrich | title=Untersuchungen aus dem Gebiete der hyperelliptischen Modulfunctionen Dritter Theil | doi=10.1007/BF01443416 | year=1892 | journal=Mathematische Annalen | volume=41 | issue=3 | pages=313–343 | url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002253909&L=1 | archive-url=https://archive.today/20130912062945/http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002253909&L=1 | url-status=dead | archive-date=September 12, 2013 }}
  • {{Citation | last1=de Jong | first1=A. J. | last2=Shepherd-Barron | first2=N. I. | last3=Van de Ven | first3=Antonius | title=On the Burkhardt quartic | doi=10.1007/BF01453578 | mr=1032936 | year=1990 | journal=Mathematische Annalen | issn=0025-5831 | volume=286 | issue=1 | pages=309–328 | url=http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002333597&L=1 | archive-url=https://archive.today/20130912062911/http://gdz.sub.uni-goettingen.de/index.php?id=11&PPN=GDZPPN002333597&L=1 | url-status=dead | archive-date=September 12, 2013 | url-access=subscription }}
  • {{Citation | last1=Freitag | first1=Eberhard | last2=Salvati Manni | first2=Riccardo | title=The Burkhardt group and modular forms | doi=10.1007/s00031-004-7002-6 | mr=2130601 | year=2004 | journal=Transformation Groups | issn=1083-4362 | volume=9 | issue=1 | pages=25–45}}
  • {{Citation | last1=Freitag | first1=Eberhard | last2=Manni | first2=Riccardo Salvati | title=Hermitian modular forms and the Burkhardt quartic | doi=10.1007/s00229-005-0603-0 | mr=2194378 | year=2006 | journal=Manuscripta Mathematica | issn=0025-2611 | volume=119 | issue=1 | pages=57–59}}
  • {{Citation | last1=Hunt | first1=Bruce | title=The geometry of some special arithmetic quotients | publisher=Springer-Verlag | location=Berlin, New York | series=Lecture Notes in Mathematics | isbn=978-3-540-61795-2 | doi=10.1007/BFb0094399 | mr=1438547 | year=1996 | volume=1637}}