Abstract
In this chapter, we explain Arthur’s description of the discrete automorphic representations of classical groups in terms of selfdual cuspidal automorphic representations of GLn. In agreement with the general philosophy of this book, we restrict our exposition to the level 1 automorphic representations, but provide a concrete form of the famous Arthur multiplicity formula for those representations whose Archimedean component is a discrete series. As a prerequisite, we discuss Shelstad’s parametrization of the individual elements of a discrete series L-packet, including several examples, and its generalization to the Adams-Johnson packets. We apply this theory to Siegel modular forms and orthogonal automorphic forms; this sheds much light on the more elementary constructions of the previous chapters. We also discuss applications to standard L-functions and Galois representations.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Notes
- 1.
In this chapter, we use the term Chevalley group as a synonym for split semisimple \(\mathbb {Z}\)-group.
- 2.
The choice of this root is fixed once and for all and will not play any role in the rest of this book. For example, since all these roots are permuted transitively by W(D n+1) ⊂O(En+1), the isomorphism class of the \(\mathbb {Z}\)-group SOn depends only on n.
- 3.
Let us mention that none of the difficulties stated by Arthur in his Chap. 9 seem to apply to the situation we are interested in, which concerns only “pure inner forms” of Chevalley groups [115].
- 4.
The reader should be aware that there are several notions of algebraic automorphic representations in the literature. Definition 8.2.7, which is essentially the one considered, for example, in [33, Sect. 18.2], but which is not the one used by Clozel in [59], is reminiscent of the notion of Hecke character of type A0 in the sense of Weil (see [43] for a clarification of the various notions).
- 5.
Following Langlands, it is suggestive to write \(z^\lambda \overline {z}^\mu \) for the element (z∕|z|)λ−μ|z|λ+μ when \(z \in \mathbb {C}^\times \) and \(\lambda ,\mu \in \mathbb {C}\) are such that \(\lambda - \mu \in \mathbb {Z}\).
- 6.
In this definition of Pp(π), it is understood that cp(π) p w(π)∕2 denotes the semisimple conjugacy class of \({\mathrm{GL}}_n(\mathbb {C})\) obtained by taking the product of the class cp(π), viewed in \({\mathrm{GL}}_n(\mathbb {C}) \supset {\mathrm{SL}}_n(\mathbb {C})\), and the scalar \(p^{w(\pi )/2} \in \mathbb {C}^\ast \subset \mathrm {GL}_n(\mathbb {C})\).
- 7.
What we denote here by \(\psi _{\mathbb {R}}\), \({\mathrm{C}}_{\nu _\infty }\), and \(\varPi (\psi _{\mathbb {R}})\) is denoted by ψ, \(\mathcal {S}_\psi \), and \(\widetilde {\varPi }_{\psi }\), respectively, in Arthur’s statement; moreover, Arthur does not give a name to ι and for u ∈ Π(ν ∞), he writes the character χ u as x↦〈x, u〉. The image of ι, a finite subset of \(\varPi _{\mathrm{unit}}(G(\mathbb {R}))\), is commonly called the Arthur packet associated with \(\psi _{\mathbb {R}}\).
- 8.
When \(L_{\varDelta ,\varphi }(\mathbb {R})\) is connected, the character ρ is determined by its differential at the identity, itself characterized by the property that the representation π Δ,φ defined in the text must have the same infinitesimal character as V .
References
J. Adams, Discrete series and characters of the component group, in Stabilization of the Trace Formula, Shimura Varieties, and Arithmetic Applications, ed. by L. Clozel, M. Harris, J.-P. Labesse, and B.-C. Ngô (International Press, 2011), Chap. 4.2.
J. Adams, D. Barbasch, D. Vogan, The Langlands classification and irreducible characters for real reductive groups, Progr. Math., vol. 104 (Birkhaüser, Boston-Basel-Berlin, 1992).
J. Adams, J. Johnson, Endoscopic groups and packets of non-tempered representations, Compos. Math. 64 (1987), pp. 271–309.
A. N. Andrianov, V. L. Kalinin, On the analytic properties of standard zeta functions of Siegel modular forms, Math. USSR, Sb. 35 (1979), pp. 1–17.
N. Arancibia, Paquets d’Arthur des représentations cohomologiques, Ph. D. thesis, Univ. Paris 6 (2015).
J. Arthur, Unipotent automorphic representations: conjectures, in Orbites unipotentes et représentations II : groupes p-adiques et réels, Astérisque 171–172 (Soc. Math. France, Paris, 1989), pp. 13–71.
J. Arthur, On the transfer of distributions: weighted orbital integrals, Duke Math. J. 99, pp. 209–283 (1999).
J. Arthur, The endoscopic classification of representations: orthogonal and symplectic groups, Colloquium Publ., vol. 61 (Amer. Math. Soc., 2013).
J. Bellaïche, G. Chenevier, The sign of Galois representations attached to automorphic forms for unitary groups, Compos. Math. 147 (2011), pp. 1337–1352.
S. Böcherer, Über die Funktionalgleichung automorpher L-Funktionen zur Siegelschen Modulgruppe, J. reine angew. Math. 362 (1985), pp. 146–168.
A. Borel, Automorphic L-functions, in Automorphic forms, representations and L-functions, II (Oregon State Univ., Corvallis, Ore.), Proc. Symp. in Pure Math. XXXIII (Amer. Math. Soc., Providence, RI, 1979), pp. 27–61.
M. Borovoi, Galois cohomology of reductive algebraic groups over the field of real numbers, preprint available at http://arxiv.org/abs/1401.5913.
K. Buzzard & T. Gee, The conjectural connections between automorphic representations and Galois representations, Automorphic forms and Galois representations Vol. 1, London Math. Soc. Lecture Note Ser. 414, Cambridge Univ. Press, Cambridge (2014), pp 135–187.
A. Caraiani, Local-global compatibility and the action of monodromy on nearby cycles, Duke Math. J. 161 (2010), pp. 2311–2413.
P.-H. Chaudouard, G. Laumon, Le lemme fondamental pondéré. I. Constructions géométriques, Compos. Math. 146 (2010), pp. 1416–1506.
P.-H. Chaudouard, G. Laumon, Le lemme fondamental pondéré. II. Énoncés cohomologiques, Annals of Math. 176 (2012), pp. 1647–1781.
G. Chenevier, M. Harris, Construction of automorphic Galois representations II, Cambridge Math. J. 1 (2013), pp. 53–73.
G. Chenevier, D. Renard, Level one algebraic cusp form of classical groups of small rank, Mem. Amer. Math. Soc., vol. 1121 (Amer. Math. Soc., Providence, RI, 2015).
L. Clozel, Motifs et formes automorphes : applications du principe de fonctorialité, in Automorphic forms, Shimura varieties, and L-functions, Vol. I (Ann Arbor, MI., 1988), Perspectives in Math. vol. 10 (Academic Press, Boston, MA, 1990).
L. Clozel, Purity Reigns Supreme, Int. Math. Res. Not., I.M.R.N., vol. 2013 (2013), pp. 328–346.
L. Clozel, M. Harris, J.-P. Labesse, Construction of automorphic Galois representations I, in Stabilization of the Trace Formula, Shimura Varieties, and Arithmetic Applications, ed. by L. Clozel, M. Harris, J.-P. Labesse, B.-C. Ngô (International Press, 2011).
J. Cogdell, Lectures on L-functions, converse theorems, and functoriality for GL n, in Lectures on automorphic L-functions, Fields Inst. Monogr. (Amer. Math. Soc., Providence, RI, 2004).
D. Ginzburg, S. Rallis, D. Soudry, The descent map from automorphic representations of GL(n) to classical groups (World Sci. Publishing, 2011).
W. Goldring, Galois representations associated to holomorphic limits of discrete series I: unitary groups, Compos. Math. 150 (2014), pp. 191–228.
T. Ikeda, Pullback of the lifting of elliptic cusp forms and Miyawaki’s conjecture, Duke Math. J. 131 (2006), pp. 469–497.
T. Ikeda, On the lifting of automorphic representations from \(\mbox{PGL}_2(\mathbb {A})\) to \(\mbox{Sp}_{2n}(\mathbb {A})\) or \(\widetilde {\mbox{Sp}_{2n+1}(\mathbb {A})}\) over a totally real field, available at https://www.math.kyoto-u.ac.jp/~ikeda/.
H. Jacquet, J. Shalika, A non-vanishing theorem for zeta-functions of GL n, Invent. Math. 38 (1976), pp. 1–16.
T. Kaletha, Rigid inner forms of real and p-adic groups, preprint available at http://arxiv.org/abs/1304.3292.
A. W. Knapp, Representation theory of semisimple groups (Princeton Univ. Press, 1986).
A. Knapp, Local Langlands correspondence: the archimedean case, in Motives vol. II, Proc. Sympos. Pure Math., vol. 55 (Amer. Math. Soc., Providence, RI, 1994), pp. 393–410.
A. Knapp & G. Zuckerman, Normalizing factors, tempered representations and L-groups, in Automorphic forms, representations and L-functions, I (Oregon State Univ., Corvallis, Ore.), Proc. Symp. in Pure Math. XXXIII (Amer. Math. Soc., Providence, RI, 1979), pp. 93–105.
R. Kottwitz, Stable trace formula: cuspidal tempered terms, Duke Math. J. 51 (1984), pp. 611–650.
R. Kottwitz, Shimura varieties and λ-adic representations, in Automorphic forms, Shimura varieties, and L-functions vol. I (Ann Arbor, MI, 1998), Perspect. Math., vol. 10 (Academic Press, 1990), pp. 161–209.
J.-P. Labesse, R. Langlands, L-indistinguishability for SL(2), Canadian J. Math. 31 (1979), pp. 726–785.
J.-P. Labesse, J.-L. Waldspurger, La formule des traces tordue d’après le Friday Morning Seminar, CRM Monogr. Ser., vol 31 (Amer. Math. Soc., Providence, RI, 2013).
R. Langlands, The classification of representations of real reductive groups, Math. Surveys Monogr., vol. 31 (Amer. Math. Soc., Provindence, RI, 1973).
R. Langlands, On the functional equation satisfied by Eisenstein series, Lecture Notes in Math., vol. 544 (Springer Verlag, 1976).
R. Langlands, Automorphic representations, Shimura varieties, and motives (Ein Märchen), in Automorphic forms, representations and L-functions, II (Oregon State Univ., Corvallis, Ore.), Proc. Symp. in Pure Math. XXXIII (Amer. Math. Soc., Providence, RI, 1979), pp. 205–246.
R. Langlands, D. Shelstad, On the definition of transfer factors, Math. Ann. 278 (1987), pp. 219–271.
P. Mezo, Character identities in the twisted endoscopy of real reductive groups, Mem. Amer. Math. Soc., vol. 222 (Amer. Math. Soc. Provindence, RI, 2013).
P. Mezo, Tempered spectral transfer in the twisted endoscopy of real groups, preprint available at http://people.math.carleton.ca/~mezo/ (2013).
S.-I. Mizumoto, Poles and residues of standard L-functions attached to Siegel modular forms, Math. Ann. 289 (1991), pp. 589–612.
C. Moeglin, J.-L. Waldspurger, Stabilisation de la formule des traces tordue VI & X, preprint available at http://webusers.imj-prg.fr/~jean-loup.waldspurger/ (2014).
Motives, ed. by U. Jannsen, S. Kleiman, J.-P. Serre, Proc. Symp. in Pure Math., vol. 55 (Amer. Math. Soc., 1991).
B. C. Ngô, Le lemme fondamental pour les algèbres de Lie, Publ. Math. Inst. Hautes Études Sci. 111 (2009), pp. 1–169.
I. Piatetski-Shapiro, S. Rallis, L-functions for the classical groups, Lecture Notes in Math., vol. 1254 (Springer Verlag, 1987), pp. 1–52.
J.-P. Serre, Cohomologie galoisienne, 5th edn., Lecture Notes in Math., vol. 5 (Springer Verlag, 1994).
D. Shelstad, Orbital integrals and a family of groups attached to a real reductive group, Ann. Sci. Éc. Norm. Sup. 12 (1979), pp. 1–31.
D. Shelstad, L-indistinguishability for real groups, Math. Ann. 259 (1982), pp. 385–430.
D. Shelstad, Tempered endoscopy for real groups III : inversion of transfer and L-packet structure, Represent. Theory 12 (2008), pp. 369–402.
D. Shelstad, Examples in endoscopy for real groups, notes from a talk at the conference Stable trace formula (Banff, 2008), available at http://andromeda.rutgers.edu/~shelstad/.
D. Shelstad, Some results on endoscopic transfer, notes from a talk at the conference L-packets (Banff, 2011), available at http://andromeda.rutgers.edu/~shelstad/.
D. Shelstad, On geometric transfer in real twisted endoscopy, Ann. of Math. 176 (2012), pp. 1919–1985.
D. Shelstad, On the structure of endoscopic transfer factors, preprint available at http://andromeda.rutgers.edu/~shelstad/.
D. Shelstad, On spectral transfer factors in real twisted endoscopy, preprint available at http://andromeda.rutgers.edu/~shelstad/.
S.-W. Shin, Galois representations arising from some compact Shimura varieties, Ann. of Math. 173 (2011), pp. 1645–1741.
O. Taïbi, Dimensions of spaces of level one automorphic forms for split classical groups using the trace formula, preprint available at http://arxiv.org/abs/1406.4247 (2014).
J. Tate, Number theoretic background, in Automorphic forms, representations and L-functions, II (Oregon State Univ., Corvallis, Ore.), Proc. Symp. in Pure Math. XXXIII (Amer. Math. Soc., Providence, RI, 1979), pp. 3–26.
D. Vogan, Representations of real reductive Lie groups, Progr. Math., vol. 15 (1981).
D. Vogan, On the unitarizability of certain series of representations, Annals of Math. 120 (1984), pp. 141–187.
D. Vogan, G. Zuckerman, Unitary representations with non-zero cohomology, Compos. Math. 53 (1984), pp. 51–90.
J.-L. Waldspurger, Endoscopie et changement de caractéristique, J. Inst. Math. Jussieu 5 (2006), pp. 423–525.
J.-L. Waldspurger, Stabilisation de la formule des traces tordues I, II, III, IV, V, VII, VIII, IX, preprints available at http://webusers.imj-prg.fr/~jean-loup.waldspurger/ (2014).
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this chapter
Cite this chapter
Chenevier, G., Lannes, J. (2019). Arthur’s Classification for the Classical \(\mathbb {Z}\)-groups. In: Automorphic Forms and Even Unimodular Lattices. Ergebnisse der Mathematik und ihrer Grenzgebiete. 3. Folge / A Series of Modern Surveys in Mathematics, vol 69. Springer, Cham. https://doi.org/10.1007/978-3-319-95891-0_8
Download citation
DOI: https://doi.org/10.1007/978-3-319-95891-0_8
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-95890-3
Online ISBN: 978-3-319-95891-0
eBook Packages: Mathematics and StatisticsMathematics and Statistics (R0)