Dark Matter in the Standard Model Extension with Singlet Quark

We analyze the possibility of hadron Dark Matter carriers consisting of singlet quark and the light standard one. It is shown that stable singlet quarks generate effects of new physics which do not contradict to restrictions from precision electroweak data. The neutral and charged pseudoscalar low-lying states are interpreted as the Dark Matter particle and its mass-degenerated partner. We evaluated their masses and lifetime of the charged component, and describe asymptotics of the potential of low-energy interactions of these particles with nucleons and with each other. Some peculiarities of Sommerfeld enhancement effect in the annihilation process are also discussed.Comment: 13 pages, 2 tabl

Dark Energy from graviton-mediated interactions in the QCD vacuum

Adopting the hypothesis about the exact cancellation of vacuum condensates contributions to the ground state energy in particle physics to the leading order in graviton-mediated interactions, we argue that the observable cosmological constant can be dynamically induced by an uncompensated quantum gravity correction to them after the QCD phase transition epoch. To start with, we demonstrate a possible cancellation of the quark-gluon condensate contribution to the total vacuum energy density of the Universe at temperatures $T<100$ MeV without taking into account the graviton-mediated effects. In order to incorporate the latter, we then calculate the leading-order quantum correction to the classical Einstein equations due to metric fluctuations induced by the non-perturbative vacuum fluctuations of the gluon and quark fields in the quasiclassical approximation. It has been demonstrated that such a correction to the vacuum energy density has a form $\varepsilon_{\Lambda}\sim G \Lambda_{\rm QCD}^6$, where $G$ is the gravitational constant, and $\Lambda_{\rm QCD}$ is the QCD scale parameter. We analyze capabilities of this approach based on the synthesis between quantum gravity in quasiclassical approximation and theory of non-perturbative QCD vacuum for quantitative explanation of the observed Dark Energy density.Comment: 21 pages, a discussion of cosmological evolution of the \Lambda-term has been added; published versio

On a possible compensation of the QCD vacuum contribution to the Dark Energy

We suggest one of the possible ways to compensate the large negative quantum-topological QCD contribution to the vacuum energy density of the Universe by means of a positive constant contribution from a cosmological Yang-Mills field. An important role of the exact particular solution for the Yang-Mills field corresponding to the finite-time instantons is discussed. An interesting connection of the compensation mechanism to the color confinement in the framework of instanton models has been pointed out. Besides the $\Lambda_{\rm QCD}$ scale, this proposal relies on one yet free dimensionless normalisation constant which cannot be fixed by the perturbative QCD theory, and thus should be fine-tuned for the exact compensation to hold.Comment: 10 pages, typos corrected, comments on fine-tuning and QCD confinement added; published versio

Vector-like technineutron Dark Matter: is a QCD-type Technicolor ruled out by XENON100?

We continue to explore a question about the existence of a new strongly coupled dynamics above the electroweak scale. The latter has been recently realized in the simplest consistent scenario, the vector-like (or chiral-symmetric) Technicolor model based upon the gauged linear sigma-model. One of the predictions of a new strong dynamics in this model, the existence of stable vector-like technibaryon states at a TeV scale, such that the lightest neutral one could serve as a Dark Matter candidate. Here, we consider the QCD-type Technicolor with SU(3)_TC confined group and one SU(2)_W doublet of vector-like techniquarks and test this model against existing Dark Matter astrophysics data. We show that the spin-independent Dirac technineutron-nucleon cross section is by far too large and ruled out by XENON100 data. We conclude that vector-like techniquark sectors with an odd group of confinement SU(2n+1)_TC, n=1,2,... and with ordinary vector-like weak SU(2)_W interactions are excluded if the technibaryon number is conserved. We discuss a possible generic TC scenario with a technibaryon sector interacting via an extra vector SU(2)_V other than the standard weak SU(2)_W and consider immediate implications for the cosmological evolution and freeze out of heavy relic technineutrons.Comment: 30 pages, 4 figures; extra clarification and motivation for the VLTC scenario has been made; minor correction

Designing Regulation for Mobile Financial Markets

Prior scholarship advocates for international harmonization of financial regulation as a solution to the problem of cross-border regulatory arbitrage. The scholarship is theoretical and rests on the contention that financial institutions can simply depart from an unfavorable regulatory regime. This Paper contributes an empirical foundation to the concern that financial institutions relocate following regulation, while also deeply qualifying claims that effective regulation requires international harmonization. Using experience from swap markets following the Dodd-Frank Act, this Article provides the first empirical evidence that financial institutions migrate in response to derivatives regulation. This Article shows that U.S. banks substantially shifted inter-bank swap trading offshore while the delivery of swaps to U.S. customers did not decline. Building on this case study, the Article develops theory for what policy goals are more susceptible to subversion through migration. Policy goals concerned with regulating relationships between financial institutions and their customers (e.g., goals of customer protection) are less vulnerable to relocation than policy goals concerned with inter-relationships between financial institutions (e.g., reduction of systemic risk). This distinction reflects well-informed priors on the relative costs and benefits of cross-border arbitrage to providers of financial services and their customers. In exploring how relocation skirted some regulations and alternative regulatory designs for achieving the same policy goals, the Article solves a longstanding puzzle for international regulation. The claim that financial institutions can avoid territorially bounded regulation appears, on its face, suspect. If an institution truly removes its operations, what legitimate interest does a jurisdiction retain in regulating that institution? Through examining how operations may be restructured across borders, the Article shows that a lack of harmonization: (a) does not affect whether a jurisdiction can unilaterally implement its policy goals, but (b) does narrow the range of regulatory designs available to achieve policy goals. Absent harmonization, jurisdictions may be limited to regulatory designs that are more difficult to implement, for instance, due to politics, administrative costs or other frictions affecting efficacious lawmaking, supervision, or enforcement

Tax Authority as Regulator and Equity Holder: How Shareholders\u27 Control Rights Could Be Adapted to Serve the Tax Authority

(Excerpt) If taxes served solely the goal of generating revenues, the tax authority could simply be granted nonvoting common shares in every corporation and rely on assertive shareholders to safeguard its interest.14 As is, however, taxes are designed to do more than raise revenues—they are also used to encourage congressionally favored behavior.15 In other words, the tax authority as interest holder does not only care about how much the taxpayer earns but also about how the taxpayer earns it. As a result, the interests of shareholders and the tax authority are not always aligned, as the latter operates under statutory directives that balance raising revenue with encouraging congressionally favored enterprise. If it were not allowed distinct control rights, the tax authority could not steer firm strategy when private and public policy diverged

Composite scalar Dark Matter from vector-like SU(2)SU(2) confinement

A toy-model with $SU(2)_{\rm TC}$ dynamics confined at high scales $\Lambda_{\rm TC}\gg 100$ GeV enables to construct Dirac UV completion from the original chiral multiplets predicting a vector-like nature of their weak interactions consistent with electroweak precision tests. In this work, we investigate a potential of the lightest scalar baryon-like (T-baryon) state $B^0=UD$ with mass $m_B\gtrsim 1$ TeV predicted by the simplest two-flavor vector-like confinement model as a Dark Matter (DM) candidate. We show that two different scenarios with the T-baryon relic abundance formation before and after the electroweak (EW) phase transition epoch lead to symmetric (or mixed) and asymmetric DM, respectively. Such a DM candidate evades existing direct DM detection constraints since its vector coupling to $Z$ boson absents at tree level, while one-loop gauge boson mediated contribution is shown to be vanishingly small close to the threshold. The dominating spin-independent (SI) T-baryon--nucleon scattering goes via tree-level Higgs boson exchange in the $t$-channel. The corresponding bound on the effective T-baryon--Higgs coupling has been extracted from the recent LUX data and turns out to be consistent with naive expectations from the light technipion case $m_{\tilde \pi}\ll \Lambda_{\rm TC}$. The latter provides the most stringent phenomenological constraint on strongly-coupled $SU(2)_{\rm TC}$ dynamics so far. Future prospects for direct and indirect scalar T-baryon DM searches in astrophysics as well as in collider measurements have been discussed.Comment: 17 pages, 14 figures; an extra figure added, discussion of mass splitting improved, minor corrections, conclusions unchange