The measurements of the anomalous like-sign dimuon charge asymmetry in ppˉp \bar{p} collisions by the D\O\ Collaboration

In this short review we present the history, an overview of the analysis, and some personal comments on the anomalous like-sign dimuon charge asymmetry measurements by the D\O\ Collaboration.Comment: 6 pages, 2 figures. arXiv admin note: text overlap with arXiv:1109.143

Constraints on neutrino masses from Baryon Acoustic Oscillation measurements

From 21 independent Baryon Acoustic Oscillation (BAO) measurements we obtain the following sum of masses of active Dirac or Majorana neutrinos: $\sum m_\nu = 0.711 - 0.335 \cdot \delta h + 0.050 \cdot \delta b \pm 0.063 \textrm{ eV,}$ where $\delta h \equiv (h - 0.678) / 0.009$ and $\delta b \equiv (\Omega_b h^2 - 0.02226) / 0.00023$. This result may be combined with independent measurements that constrain the parameters $\sum m_\nu$, $h$, and $\Omega_b h^2$. For $\delta h = \pm 1$ and $\delta b = \pm 1$, we obtain $m_\nu < 0.43$ eV at 95\% confidence.Comment: 2 pages, 0 figure

Measurements of the cosmological parameters Ωm\Omega_m, Ωk\Omega_k, Ωde(a)\Omega_\textrm{de}(a), H0H_0, and ∑mν\sum m_\nu

From Baryon Acoustic Oscillation measurements with Sloan Digital Sky Survey SDSS DR14 galaxies, and the acoustic horizon angle $\theta_*$ measured by the Planck Collaboration, we obtain $\Omega_m = 0.2724 \pm 0.0047$, and $h + 0.020 \cdot \sum{m_\nu} = 0.7038 \pm 0.0060$, assuming flat space and a cosmological constant. We combine this result with the 2018 Planck `TT,TE,EE$+$lowE$+$lensing' analysis, and update a study of $\sum m_\nu$ with new direct measurements of $\sigma_8$, and obtain $\sum m_\nu = 0.27 \pm 0.08$ eV assuming three nearly degenerate neutrino eigenstates. Measurements are consistent with $\Omega_k = 0$, and $\Omega_\textrm{de}(a) = \Omega_\Lambda$ constant.Comment: 11 pages, 6 figure

Anomalous dimuon charge asymmetry in proton-antiproton collisions

We present an overview of the measurements of the like-sign dimuon charge asymmetry by the DO Collaboration at the Fermilab Tevatron proton-antiproton Collider. The results differ from the Standard Model prediction of CP violation in mixing and interference of B^0 and B^0_s by 3.6 standard deviations.Comment: 6 pages, 6 figures, Proceedings of Rencontres de Moriond, EW session, 201

Trying to understand dark matter

We present some "back-of-the-envelope" calculations to try to understand cold dark matter, its searches, and extensions of the Standard Model. Some of the insights obtained from this exercise may be useful.Comment: 16 pages, 1 figur

Built to evolve

We study the probabilities of evolution based on random mutations and natural selection. We conclude that evolution to multicellular eukaryots, or even prokaryots, is unlikely to be the result of only random mutations. Complex organisms have evolved through several mechanisms besides random mutations, namely DNA recombination, adaptive mutations, and acquisition of foreign DNA. We conclude that all living organisms, in addition to being self-organizing and reproducing (autopoyetic), have built-in mechanisms of evolution, some of which respond in very specific ways to environmental stress.Comment: 10 pages, 4 figure

Understanding the like-sign dimuon charge asymmetry in ppˉp \bar{p} collisions

The D\O\ collaboration has measured the like-sign dimuon charge asymmetry in $p \bar{p}$ collisions at the Fermilab Tevatron collider. The result is significantly different from the standard model expectation of CP violation in mixing. In this paper we consider the possible causes of this asymmetry and identify one standard model source not considered before. It decreases the discrepancy of the like-sign dimuon charge asymmetry with the standard model prediction, although does not eliminate it completely.Comment: 7 pages, 0 figure

Global Warming: some back-of-the-envelope calculations

We do several simple calculations and measurements in an effort to gain understanding of global warming and the carbon cycle. Some conclusions are interesting: (i) There has been global warming since the end of the "little ice age" around 1700. There is no statistically significant evidence of acceleration of global warming since 1940. (ii) The increase of CO_2 in the atmosphere, beginning around 1940, accurately tracks the burning of fossil fuels. Burning all of the remaining economically viable reserves of oil, gas and coal over the next 150 years or so will approximately double the pre-industrial atmospheric concentration of CO_2. The corresponding increase in the average temperature, due to the greenhouse effect, is quite uncertain: between 1.3 and 4.8K. This increase of temperature is (partially?) offset by the increase of aerosols and deforestation. (iii) Ice core samples indicate that the pre-historic CO_2 concentration and temperature are well correlated. We conclude that changes in the temperatures of the oceans are probably the cause of the changes of pre-historic atmospheric CO_2 concentration. (iv) Data suggests that large volcanic explosions can trigger transitions from glacial to interglacial climates. (v) Most of the carbon fixed by photosynthesis in the Amazon basin returns to the atmosphere due to aerobic decay.Comment: 19 pages, 4 figure

Limits on the Two Higgs Doublet Model from meson decay, mixing and CP violation

Using the experimental data on meson decay rates, mixing and CP violation we set competitive upper and lower limits to the parameter tan(beta) as a function of the mass of the charged Higgs m_H in the Two Higgs Doublet Model (Model II).Comment: 9 page

Ratio between two Λ\Lambda and Λˉ\bar{\Lambda} production mechanisms in pp scattering

We consider $\Lambda$ and $\bar{\Lambda}$ production in a wide range of proton scattering experiments. The produced $\Lambda$ and $\bar{\Lambda}$ may or may not contain a diquark remnant of the beam proton. The ratio of these two production mechanisms is found to be a simple universal function $r = [ \kappa/(y_p - y) ]^i$ of the rapidity difference $y_p - y$ of the beam proton and the produced $\Lambda$ or $\bar{\Lambda}$, valid over four orders of magnitude, from $r \approx 0.01$ to $r \approx 100$, with $\kappa = 2.86 \pm 0.03 \pm 0.07$, and $i = 4.39 \pm 0.06 \pm 0.15$.Comment: 2 pages, 2 figure