Examining Vietnam’s COVID-19 response

A recent study by Vietnamese social scientists looked into the initial success of Vietnam’s response to COVID-19

Right Handed Neutrino Currents in the SU(3)_LxU(1)_N Electroweak Theory

A version of the \mbox{SU(3)}_L\otimes \mbox{U(1)}_N electroweak theory in which there are right-handed neutrino currents is reconsidered in detail. We argue that in order to have a result consistent with low-energy one, the right-handed neutrino component must be treated as correction instead of an equivalent spin state. The data from the $Z$-decay allow us to fix the limit for $\phi$ as $-0.00285 \leq \phi \leq 0.00018$. From the neutrino neutral current scattering, we estimate a bound for the new neutral gauge boson $Z^2$ mass in the range of 400 GeV. A bound for the new charged and neutral (non-Hermitian) gauge bosons $Y^{\pm}, X^o$ is also obtained from symmetry-breaking hierarchy.Comment: 13 pages, latex, no figures, Presented at the 2nd Recontres du Vietnam - Physics at the Frontiers of the Standard Model, Ho Chi Minh City, Vietnam, 21-28 October 199

On a conjecture by Pierre Cartier about a group of associators

In \cite{cartier2}, Pierre Cartier conjectured that for any non commutative formal power series $\Phi$ on $X=\{x_0,x_1\}$ with coefficients in a \Q-extension, $A$, subjected to some suitable conditions, there exists an unique algebra homomorphism $\varphi$ from the \Q-algebra generated by the convergent polyz\^etas to $A$ such that $\Phi$ is computed from $\Phi_{KZ}$ Drinfel'd associator by applying $\varphi$ to each coefficient. We prove $\varphi$ exists and it is a free Lie exponential over $X$. Moreover, we give a complete description of the kernel of polyz\^eta and draw some consequences about a structure of the algebra of convergent polyz\^etas and about the arithmetical nature of the Euler constant