Comment on: How the result of a single coin toss can turn out to be 100 heads

Ferrie and Combes [PRL 113 120404 (2014)] produce a classical measurement scheme that supposedly exhibits `anomalous' weak values. I show that their model is flawed due to an incorrect definition of the weak value. As a consequence their claims are invalid.Comment: Includes a brief response to the the published reply [Phys. Rev. Lett. 114, 118902 (2015)

Exclusive vector meson electroproduction at HERA

The latest results on exclusive vector meson electroproduction from HERA are reviewed. In particular, the new high-statistics measurements of the rho^0 electroproduction are presented and compared to several models.Comment: 8 pages, 15 figures, talk presented at the 12th internationa conference of elastic and diffractive scattering, Hamburg, May 21-25, 200

General Bilinear Forms

We introduce the new notion of general bilinear forms (generalizing sesquilinear forms) and prove that for every ring $R$ (not necessarily commutative, possibly without involution) and every right $R$-module $M$ which is a generator (i.e. $R_R$ is a summand of $M^n$ for some $n\in\N$), there is a one-to-one correspondence between the anti-automorphisms of \End(M) and the general regular bilinear forms on $M$, considered up to similarity. This generalizes a well-known similar correspondence in the case $R$ is a field. We also demonstrate that there is no such correspondence for arbitrary $R$-modules. We use the generalized correspondence to show that there is a canonical set isomorphism between the orbits of the left action of \Inn(R) on the anti-automorphisms of $R$ and the orbits of the left action of \Inn(M_n(R)) on the anti-automorphisms of $M_n(R)$, provided $R_R$ is the only right $R$-module $N$ satisfying $N^n\cong R^n$. We also prove a variant of a theorem of Osborn. Namely, we classify all semisimple rings with involution admitting no non-trivial idempotents that are invariant under the involution.Comment: 26 page