Revisiting the role of CP-conserving processes in cosmological particle–antiparticle asymmetries

We point out qualitatively different possibilities on the role of CP-conserving processes in generating cosmological particle–antiparticle asymmetries, with illustrative examples from models in leptogenesis and asymmetric dark matter production. In particular, we consider scenarios in which the CP-violating and CP-conserving processes are either both decays or both scatterings, thereby being naturally of comparable rates. This is in contrast to the previously considered CP-conserving processes in models of leptogenesis in different see-saw mechanisms, in which the CP-conserving scatterings typically have lower rates compared to the CP-violating decays, due to a Boltzmann suppression. We further point out that the CP-conserving processes can play a dual role if the asymmetry is generated in the mother sector itself, in contrast to the conventional scenarios in which it is generated in the daughter sector. This is because, the CP-conserving processes initially suppress the asymmetry generation by controlling the out-of-equilibrium number densities of the bath particles, but subsequently modify the ratio of particle antiparticle yields at the present epoch by eliminating the symmetric component of the bath particles through pair-annihilations, leading to a competing effect stemming from the same process at different epochs. We find that the asymmetric yields for relevant particle–antiparticle systems can vary by orders of magnitude depending upon the relative size of the CP-conserving and violating reaction rates.

Theoretical modeling of defects in the molecular crystal of 2-(2'-hydroxyphenyl)benzothiazole

2-(2'-hydroxyphenyl)benzothiazole is a photoreactive compound that exhibits excited state intramolecular proton transfer in the structure with an OH...N hydrogen bond. Energy of various structures is calculated for isolated molecules, clusters and periodic structures of 2-(2'-hydroxyphenyl)benzothiazole by density-functional based tight-binding methods. It is shown that the most stable conformation of the isolated molecule is a planar structure with an OH...N hydrogen bond. Other conformations have significantly larger energy in comparison with the average room temperature heat energy that implies a low equilibrium number of those structures in non-polar solvents. In crystal the defect with lowest energy is non-hydrogen-bonded conformation formed by rotation of the OH bond. The energy of this defect is close to the energy difference for corresponding conformations of the isolated molecule. For other conformations, the energy values of the defects are larger than the energy differences for isolated molecules. In contrast to the crystal of 2-(2'-hydroxyphenyl)benzoxazole, energy of the defect caused by the entire molecule reorientation is comparable with the energy of defects caused by different conformations.

How do Optimistic Individuals Affect Insurance Advertisements?

Some people have optimistic expectations regarding their accident probability, and thus, refrain from purchasing adequate insurance. This study investigates how insurance firms use advertisements to lower the ratio of optimistic individuals in the market. The main results are as follows: first, the optimal level of advertisements is maximized when the insurance premium is moderate. Second, the maximum level of advertisement varies according to the degree of optimism, which is measured by the difference between accurate and optimistic accident probabilities. Third, the advertisement decision is affected by the free-rider problem, and the equilibrium number of insurance firms with advertisement is always larger than that of firms without advertisement in a competitive insurance market.

Optimal Pricing Decisions for the Online Video Platform Under Customer Choice

With the development of the video-on-demand (VOD) technology, the audiences can decide to skip the advertisements by paying the video platform. This paper examines the optimal pricing decisions for an online video platform by considering the customer’s choice behavior. Based on a two-sided market that is composed of a monopolistic video platform, advertisers and audiences, we show that the platform’s optimal price charging from the advertisers is decreasing in the degree of audiences’ disutility for advertisements, while the optimal price charging from the audiences is convex in the degree of audiences’ disutility for advertisements. More interestingly, we find that the equilibrium number of advertisers on the platform and the video platform’s profit are both convex in the degree of audiences’ disutility for advertisements, which are counter-intuitive. We also extend our model to the case with two duopolistic platforms and find that the optimal number of advertisers on the platform is concave in the degree of audiences’ disutility for advertisements. Numerical experiments are further presented to reveal the managerial insights.

The Effects of Mandatory Audit Firm Rotation on Client Importance and Audit Industry Concentration

ABSTRACT Recently, a system of audit firm rotation has been implemented for the audits of listed companies conducted in the European Union (EU). In the U.S., in contrast, the regulator decided against such rotation. Whereas proponents argue that rotation would strengthen independence and decrease audit market concentration, opponents stress the importance of auditors' learning effects, which would be eliminated by a change in auditors. In extending the market matching model of Salop (1979), we provide an analysis that integrates these contradictory views. We assume that both auditors' industry expertise and their experience in auditing a client decrease audit costs. We investigate the bidding strategies applied to re-acquire clients that were lost due to rotation, auditors' profit contributions, the equilibrium number of auditors (i.e., audit market concentration), and the economic importance of specific clients. Our findings indicate that the regulators' goals of simultaneously decreasing client importance and audit market concentration are in direct conflict and, therefore, the rotation system might have unintended consequences. Our model, thus, suggests how different institutional parameters give rise to economic forces that can support diverging decisions regarding the implementation of MAR.

A general equilibrium analysis of food industry considering the food quality

By establishing a dynamic equilibrium model, the paper analyses the equilibrium of the food industry and the equilibrium about the food quality as well as quantity is achieved. Firstly, the study examines the effects of competitions on the price, outputs, profits and social welfare. The authors argue that competition reduces the food quality. Secondly, this paper shows that consumers benefit from the quality regulation while producers undertake a loss. Moreover, social welfare first increases then decreases with the regulation. Thirdly, the optimal quality regulation is presented and a higher quality regulation reduces competition, while the lower quality regulation promotes it. Finally, the effects of fixed costs on the equilibrium number of firms in the corresponding industry are captured.  

Competitive Entry In Ontarios Deregulated Power Generation Industry

In this paper we investigate the issues involved in the deregulation of an electricity market. The paper focuses on efficiency considerations, comparing the gap between the socially efficient outcome and that achievable by a market. We model this problem with two-sided uncertainty: the uncertain market demand and the uncertain cost of production. In each case, we find the social optimum and the equilibrium outcome of the deregulated market. Conditions when deregulated industry cannot generate the socially optimal number of firms are identified. The relationship between market demand, the degree of risk-aversion of private firms, and the equilibrium number of firms is investigated.

Optimum Structure of the Banking Market: How Many Banks Are Necessary for Russia?

The number of classical banks in the world has reduced. In the majority of countries the number of banks does not exceed 200. The uniqueness of the Russian banking sector is that in this respect it takes the third place in the world after the USA and Germany. The paper reviews the conclusions of the economic theory about the optimum structure of the banking market. The empirical analysis shows that the number of banks in a country is influenced by the size of its territory, population number and GDP per capita. Our econometric estimate is that the equilibrium number of banks in Russia should be in a range of 180-220 units.