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On R-triviality of F4

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Abstract

It is known that simple algebraic groups of type F4 defined over a field k are precisely the full automorphism groups of Albert algebras over k. We explore R-triviality for the algebraic group Aut(A) when A is an Albert algebra. In this paper, we consider the case when A arises from the first Tits construction. We prove that Aut(A) is R-trivial, in the sense of Manin.

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References

  1. S. Alsaody, V. Chernousov and A. Pianzola, R-triviality of groups of type F4arising from the first Tits construction, Bulletin of the London Mathematical Society 53 (2021), 535–547.

    Article  MathSciNet  Google Scholar 

  2. S. Alsaody, V. Chernousov and A. Pianzola, On the Tits-Weiss conjecture and the Kneser-Tits conjecture for \(E_{7,1}^{78}\) and \(E_{8,2}^{78}\), https://arxiv.org/abs/1911.12908.

  3. V. Chernousov and A. Merkurjev, R-equivalence and special unitary group, Journal of Algebra 209 (1998), 175–198.

    Article  MathSciNet  Google Scholar 

  4. V. I. Chernousov and V. P. Platonov, The rationality problem for semisimple group varieties, Journal für die Reine und Angewandte Mathematik 504 (1998), 1–28.

    MathSciNet  MATH  Google Scholar 

  5. J. C. Ferrar and H. P Petersson, Exceptional simple Jordan algebras and Galois cohomology, Archiv der Mathematik 61 (1993), 517–520.

    Article  MathSciNet  Google Scholar 

  6. S. Garibaldi, Kneser-Tits for a rank 1 form of E6(After Veldkamp), Compositio Mathematica 143 (2007), 191–200.

    Article  MathSciNet  Google Scholar 

  7. P. Gille, Spécialisation de la R-équivalence pour les groupes réductifs, Transactions of the American Mathematical Society 356 (2004), 4465–4474.

    Article  MathSciNet  Google Scholar 

  8. P. Gille, Le Probléme de Kneser-Tits, Astérisque 326 (2009), 39–81.

    MATH  Google Scholar 

  9. N. Jacobson, Lie Algebras, Interscience Tracts in Pure and Applied Mathematics, Vol. 10, Interscience, New York-London, 1962.

    MATH  Google Scholar 

  10. N. Jacobson, Structure and Representations of Jordan Algebras, Colloquium Publications, Vol. 39, American Mathematical Society, Providence, RI, 1968.

    Book  Google Scholar 

  11. M. A. Knus, A. Merkurjev, M. Rost and J. P. Tignol, The Book of Involutions, Colloquium Publications, Vol. 44, American Mathematical Society, Providence, RI, 1998.

    Google Scholar 

  12. Yu. I. Manin, Cubic Forms, North-Holland Mathematical Library, Vol. 4, North-Holland, Amsterdam-London, 1974.

    Google Scholar 

  13. K. McCrimmon, Generically algebraic algebras, Transactions of the American Mathematical Society 127 (1967), 527–551.

    Article  MathSciNet  Google Scholar 

  14. K. McCrimmon, The Freudenthal-Springer-Tits constructions of exceptional Jordan algebras, Transactions of the American Mathematical Society 139 (1969), 495–510.

    Article  MathSciNet  Google Scholar 

  15. R. Parimala, R. Sridharan and M. L. Thakur, A classification theorem for Albert algebras, Transactions of the American Mathematical Society 350 (1998), 1277–1284.

    Article  MathSciNet  Google Scholar 

  16. R. Parimala, J. P. Tignol and R. M. Weiss, The Kneser-Tits conjecture for groups with Tits-index \(E_{8,2}^{66}\) over an arbitrary field, Transformation Groups 17 (2012), 209–231.

    Article  MathSciNet  Google Scholar 

  17. H. P. Petersson, Structure theorems for Jordan algebras of degree three over fields of arbitrary characteristic, Communications in Algebra 32 (2004), 1019–1049.

    Article  MathSciNet  Google Scholar 

  18. H. P. Petersson, A survey on Albert algebras, Transformation Groups 24 (2019), 219–278.

    Article  MathSciNet  Google Scholar 

  19. H. P. Petersson and M. Racine, Cubic subfields of exceptional simple Jordan algebras, Proceedings of the American Mathematical Society 91 (1984), 31–36.

    Article  MathSciNet  Google Scholar 

  20. H. P. Petersson and M. Racine, Springer forms and the first Tits construction of exceptional Jordan division algebras, Manuscripta Mathematica 45 (1984), 249–272.

    Article  MathSciNet  Google Scholar 

  21. H. P. Petersson and M. Racine, Classification of algebras arising from the Tits process, Journal of Algebra 98 (1986), 244–279.

    Article  MathSciNet  Google Scholar 

  22. H. P. Petersson and M. Racine, Jordan algebras of degree 3 and the Tits process, Journal of Algebra 98 (1986), 211–243.

    Article  MathSciNet  Google Scholar 

  23. H. P. Petersson and M. Racine, Albert algebras, in Jordan Algebras (Oberwolfach, 1992), de Gruyter, Berlin, 1994, pp. 197–207.

    MATH  Google Scholar 

  24. H. P. Petersson and M. Thakur, The étale Tits process of Jordan algebras revisited, Journal of Algebra 273 (2004), 88–107.

    Article  MathSciNet  Google Scholar 

  25. V. P. Platonov and A. Rapinchuk, Algebraic Groups and Number Theory, Pure and Applied Mathematics, Vol. 139, Academic Press, Boston, MA, 1994.

    Google Scholar 

  26. G. Prasad, On the Kneser-Tits problem for triality forms, Commentarii Mathematici Helvetici 83 (2008), 913–925.

    Article  MathSciNet  Google Scholar 

  27. T. A. Springer, Linear Algebraic Groups, Progress in Mathematics, Vol. 9, Birkhäuser, Boston, MA, 1998.

    Google Scholar 

  28. T. A. Springer and F. D. Veldkamp, Octonions, Jordan Algebras and Exceptional Groups, Springer Monographs in Mathematics, Springer, Berlin, 2000.

    Google Scholar 

  29. M. Thakur, Automorphisms of Albert algebras and a conjecture of Tits and Weiss, Transactions of the American Mathematical Society 365 (2013), 3041–3068.

    Article  MathSciNet  Google Scholar 

  30. M. Thakur, Automorphisms of Albert algebras and a conjecture of Tits and Weiss II, Transactions of the American Mathematical Society 372 (2019), 4701–4728.

    Article  MathSciNet  Google Scholar 

  31. M. Thakur, Albert algebras and the Tits-Weiss conjecture, https://arxiv.org/abs/1911.04976.

  32. M. Thakur, On R-triviality of F4-II, https://arxiv.org/abs/2001.09749.

  33. V. E. Voskresenskii, Algebraic Groups and Their Birational Invariants, Translation of Mathematical Monographs, Vol. 179, American Mathematical Society, Providence, RI, 1998.

    Google Scholar 

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Acknowledgement

This work was partially funded by the DFG under Germany’s Excellence Strategy “EXC 2044-390685587, Mathematics Münster: Dynamics-Geometry-Structure”, when the author visited Math-Institute, Münster, in the summer of 2019. We thank Linus Kramer for his support. The author thanks Holger Petersson for some fruitful discussions at Hagen during the above period. We thank the referee for some very constructive suggestions that have improved the readability of the paper.

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Correspondence to Maneesh Thakur.

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Thakur, M. On R-triviality of F4. Isr. J. Math. 244, 145–161 (2021). https://doi.org/10.1007/s11856-021-2175-4

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  • DOI: https://doi.org/10.1007/s11856-021-2175-4

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