bio  website  www2.imperial.ac.uk/~rpanneko 

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I am a postdoc at Imperial College. My interests are rational points on varieties, in particular K3 surfaces and abelian varieties.
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Is any quadric birational to a product of BrauerSeveri varieties?
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Is any quadric birational to a product of BrauerSeveri varieties?
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Is any quadric birational to a product of BrauerSeveri varieties?
Thank you for the question! It seems that the same argument should work for any quadric $V$ over a number field that fails to have local points at exactly one place. 
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Is any quadric birational to a product of BrauerSeveri varieties?
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Is any quadric birational to a product of BrauerSeveri varieties?
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answered  Is any quadric birational to a product of BrauerSeveri varieties? 
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Can a nonsurjective polynomial map from an infinite field to itself miss only finitely many points?
Does this generalize at all to maps $f_k \colon V(k) \rightarrow W(k)$, where $V,W$ are $k$varieties (or $k$schemes) and where $f_k$ is induced by a morphism $f \colon V \rightarrow W$? (And what if $f$ is a rational map?) 
Apr 14 
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Find two triangles of longest side length 25?
It can be deduced from yours. Write $t = m/n$ with $m,n$ integers, then multiply the three sidelengths by $kn^2$ for an arbitrary integer $k$. 
Apr 14 
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Find two triangles of longest side length 25?
Your parametrization only gives some Pythagorean triangles, not all. You should use $(a,b,c)=(k(m^2n^2),2kmn,k(m^2+n^2))$, with $k,m,n$ integers. 
Apr 14 
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Find two triangles of longest side length 25?
They are 152025 and 72425. 
Apr 12 
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Quadratic twist of an elliptic curve given by nonWeierstrass model
I think joro is right: the isomorphism class of $E_d$ does not depend on the choice of origin on $E$. You see this by simply writing down the obvious $\overline{k}$isomorphism between $E_d$ and $E_d'$ (which we define as the twist by the same cocycle but wrt some different choice of origin on $E$) and check that it is defined over $k$. 
Apr 12 
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Quadratic twist of an elliptic curve given by nonWeierstrass model
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Quadratic twist of an elliptic curve given by nonWeierstrass model
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Quadratic twist of an elliptic curve given by nonWeierstrass model
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answered  Quadratic twist of an elliptic curve given by nonWeierstrass model 
Apr 9 
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Algebraic Geometry for nonmathematician
I always found the Harris book much more difficult than the two Shafarevich volumes. There are many examples in Harris's book, but there are also many claims that are left to the reader, and the prerequisites are quite substantial. 
Mar 18 
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Picard number of Prym Variety
But how do you know that the desired conclusion is false for a generic curve $C$? Is this somehow related to the work of Maulik and Poonen (NéronSeveri groups under specialization)? 
Mar 2 
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“GrossZagier” formulae outside of number theory
Are there examples where the class of $D \subset M \times M$ in the cohomology of $M \times M$ is trivial? (Since it has nonzero intersection number with $M \times \{ \operatorname{pt} \}$, I am tempted to think the answer can't be yes.) 
Mar 1 
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Functoriality of Br(X)
There is no inclusion $X \rightarrow \overline{X}$, but there is a projection going the other way. :) 
Feb 27 
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Consecutive square values of cubic polynomials
Very nice answer. By the way, the minus in one of the indices in your displayed formula should be a plus. (I deleted my previous comment, whose validity rested on the assumption that the $V_c$ are smooth. I thought I had an easy proof of this, but it was wrong.) 