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3 votes
0 answers
167 views

Simplicial resolution for commutative group scheme

Let $X$ be a quasi-projective $k$-variety. In this case the symmetric power $S^d(X)$ is well-defined. If $S^\bullet(X)=\bigsqcup_{n>0}S^d(X)$, where we suppose $S^0(X)=\operatorname{spec}(k)$, then ...
Sam's user avatar
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1 vote
0 answers
90 views

The splitting pattern of the Killing form of an algebraic group and the Tits index

Let us assume that $G$ is an anisotropic semisimple, connected algebraic group over a field $k$ of characteristic zero. Let $K_G$ denote the class of its Killing form in the Witt ring of $k$. Let $X$ ...
nxir's user avatar
  • 1,479
2 votes
0 answers
141 views

Are Generalized Involution Varieties hyperlane sections of Generalized Severi Brauer Varieties?

Let $A$ be a central, simple algebra of degree $2n$ with orthogonal involution $\sigma$. Let SB$(A)$ the Severi-Brauer variety, which is the variety of left ideals of reduced dimension one in $A$. ...
nxir's user avatar
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4 votes
0 answers
161 views

Quadrics contained in the (complex) Cayley plane

In the paper Ilev, Manivel - The Chow ring of the Cayley plane we can learn, that $CH^8(X)$, with $X := E_6/P_1$, denoting the Cayley plane, has three generators with one of them being the class of ...
nxir's user avatar
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5 votes
1 answer
450 views

Constructing groups of Type E7 with certain Tits Index

In a new survey on $E_8$, namely Skip Garibaldi - E8 the most exceptional group , the author gives an example (Example 8.4., page 15) on how to construct a group of type E8 with a prescribed Tits-...
nxir's user avatar
  • 1,479
4 votes
0 answers
121 views

Norm variety for n=5, p=2 not isomorphic to a quadric

In the paper "Motivic construction of cohomological invariants", the author displays a list of known norm varieties for several $n,p$ on page $11$. For $p=2, n=5$ it says that a norm variety is given ...
nxir's user avatar
  • 1,479
5 votes
0 answers
291 views

Hyperplane sections of principal homogeneous spaces

Let $P_i$ denote the $i$-th vertex in the Dynkin diagramm of an algebraic group. It symbolizes a parabolic subgroup of $G$ corresponding to the other vertices, meaning $G/P_i$ is a smooth, projective, ...
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5 votes
1 answer
341 views

Motives of a variety of type D4

Over the last decade Nikita Semenov, Skip Garibaldi and others have made some progress in the theory of cohomological invariants, (Rost)-motives and motivic decompositions of algebraic groups. For ...
nxir's user avatar
  • 1,479
8 votes
1 answer
467 views

Known norm varieties and the Bloch-Kato conjecture

The Bloch-Kato conjecture states that $K_M^n(k)/l \simeq H^n(k,\mu^{\otimes n}_l)$ for every $n,l$,while $l$ is invertible in $k$. A important part in the proof of the Bloch-Kato conjecture is to ...
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