Modular Constraints on Superconformal Field Theories

We constrain the spectrum of $\mathcal{N}=(1, 1)$ and $\mathcal{N}=(2, 2)$ superconformal field theories in two-dimensions by requiring the NS-NS sector partition function to be invariant under the $\Gamma_\theta$ congruence subgroup of the full modular group $SL(2, \mathbb{Z})$. We employ semi-definite programming to find constraints on the allowed spectrum of operators with or without $U(1)$ charges. Especially, the upper bounds on the twist gap for the non-current primaries exhibit interesting peaks, kinks, and plateau. We identify a number of candidate rational (S)CFTs realized at the numerical boundaries and find that they are realized as the solutions to modular differential equations associated to $\Gamma_\theta$. Some of the candidate theories have been discussed by H\"ohn in the context of self-dual extremal vertex operator (super)algebra. We also obtain bounds for the charged operators and study their implications to the weak gravity conjecture in AdS$_3$.Comment: 50 pages, 16 figure

Review of \u3cem\u3eCombating Poverty: Quebec\u27s Pursuit of a Distinctive Welfare State\u3c/em\u3e Axel Van Den Berg, Charles Plante, Hicham Raiq, Christine Proulx, and Sam Faustmann

Axel Van Den Berg, Charles Plante, Hicham Raiq, Christine Proulx, and Sam Faustmann, Combating Poverty: Quebec’s Pursuit of a Distinctive Welfare State. University of Toronto Press (2017), 232 pages, $37.50 (hardcover)

Modular Constraints on Conformal Field Theories with Currents

We study constraints coming from the modular invariance of the partition function of two-dimensional conformal field theories. We constrain the spectrum of CFTs in the presence of holomorphic and anti-holomorphic currents using the semi-definite programming. In particular, we find the bounds on the twist gap for the non-current primaries depend dramatically on the presence of holomorphic currents, showing numerous kinks and peaks. Various rational CFTs are realized at the numerical boundary of the twist gap, saturating the upper limits on the degeneracies. Such theories include Wess-Zumino-Witten models for the Deligne's exceptional series, the Monster CFT and the Baby Monster CFT. We also study modular constraints imposed by $\mathcal{W}$-algebras of various type and observe that the bounds on the gap depend on the choice of $\mathcal{W}$-algebra in the small central charge region.Comment: 49 pages, 23 figure

Metal-organic chemical vapor deposition of 2D van der Waals materials-The challenges and the extensive future opportunities

The last decade has witnessed significant progress in two-dimensional van der Waals (2D vdW) materials research; however, a number of challenges remain for their practical applications. The most significant challenge for 2D vdW materials is the control of the early stages of nucleation and growth of the material on preferred surfaces to eventually create large grains with digital thickness controllability, which will enable their incorporation into high-performance electronic and optoelectronic devices. This Perspective discusses the technical challenges to be overcome in the metal-organic chemical vapor deposition (MOCVD) growth of 2D group 6 transition metal dichalcogenide (TMD) atomic crystals and their heterostructures, as well as future research aspects in vdW epitaxy for 2D TMDs via MOCVD. In addition, we encourage the traditional MOCVD community to apply their expertise in the field of "2D vdW materials," which will continue to grow at an exponential rate

Temporal Discounting and Inter-Temporal Choice in Rhesus Monkeys

Humans and animals are more likely to take an action leading to an immediate reward than actions with delayed rewards of similar magnitudes. Although such devaluation of delayed rewards has been almost universally described by hyperbolic discount functions, the rate of this temporal discounting varies substantially among different animal species. This might be in part due to the differences in how the information about reward is presented to decision makers. In previous animal studies, reward delays or magnitudes were gradually adjusted across trials, so the animals learned the properties of future rewards from the rewards they waited for and consumed previously. In contrast, verbal cues have been used commonly in human studies. In the present study, rhesus monkeys were trained in a novel inter-temporal choice task in which the magnitude and delay of reward were indicated symbolically using visual cues and varied randomly across trials. We found that monkeys could extract the information about reward delays from visual symbols regardless of the number of symbols used to indicate the delay. The rate of temporal discounting observed in the present study was comparable to the previous estimates in other mammals, and the animal's choice behavior was largely consistent with hyperbolic discounting. Our results also suggest that the rate of temporal discounting might be influenced by contextual factors, such as the novelty of the task. The flexibility furnished by this new inter-temporal choice task might be useful for future neurobiological investigations on inter-temporal choice in non-human primates

라오스 소비자 특성에 따른 우유의 속성별 가치 평가: 가상 제품과의 비교

학위논문 (석사)-- 서울대학교 국제농업기술대학원 국제농업기술학과, 2017. 8. 김태윤.Lao' dairy market is small and under developed due to low level of per capital income with around 7 million population. Most milk products are imported from Thailand and Vietnam. The Lao government had tried to develop its national brand, for example, Nabong milk, however it failed in 2008 because of lack of competitiveness compared to other importing milk products. The Lao government still has a plan to develop its dairy industry by making its own national brand. The Lao government's development plan continuously hope to develop the dairy industry. With that in mind, this study this study estimates random utility function of fluid milk using 1,165 survey data in Laos. It finds out both products attributes and individual characteristics affecting consumers preference on the milk and compares four real milk products and hypothetical one with the brand of Laos-Korea that has never been traded assuming a potential influence of Korea caused by the bilateral cooperation between two countries. Lao national brand, Nabong is also included for understanding peoples awareness although it is not available at current market. Results show that the calories has a positive relationship with consumers preference while the price and fat have negative one. The decision for choosing each brand is significantly affected by individual characteristics such as gender, age, whether or not to live with kids, the level of education, income, the frequency of purchasing a milk per week, and the region where they are living. The preference for five brands appears in the order of the Foremost, Nabong, Thai-Danish, Meiji, and Lao-Korea, and probabilities of purchasing each brand at the mean level are 30.9%, 17.48%, 21.48%, 15.0% and 10.39%, respectively. In addition, policy of promoting livestock and milk industry in Laos would be more effective if it focuses more on having a good national brand, female consumers, family with kids, high quality of milk products, the young generation, and Vientiane capital areas.1. Introduction 1 1.1. Current Status of Milk Market in Laos 1 1.2. Background and Purpose 7 2. Literature Review and Methodology 12 2.1. Literature Review 12 2.2. Random Utility Model 16 3. Survey and Data Description 18 3.1. Survey Design 18 3.2. Survey Procedure 23 3.3. Descriptive Summary for Survey Response 30 4. Results 34 5. Conclusion and Implication 42 5.1. Conclusion 42 5.2. Implication 49 References 53 Appendix 57 Abstract in Korean 79 Abstract in Laotian 81Maste

Paths to Democracy, the Post-Cold War and 21st Century New Standard of Civilization, the New Wave Expansion of International Society: China, South Korea and Iraq

In my dissertation, I examine two main research questions: 1. Can we regard democracy as the new standard of civilization and the new wave expansion of international society in the post-Cold War era and in the 21st century? and 2. Should we think that each path toward democracy is relatively different based on the characteristics of each international society and the internal and external variables of each state? In my dissertation, I use typology to demonstrate that each country has taken its own unique path toward democracy, and that democracy has become the post-Cold War and 21st century new standard of civilization and new wave expansion of international society. A pluralist international society, a solidarist international society, and a liberal anti-pluralist international society have influenced paths toward democracy, along with institutions such as international law, diplomacy, Great Powers and international organizations. In addition to those, internal variables such as each country\u27s history, culture, politics, economy, military power and foreign policy can also influence paths toward democracy. However, in my dissertation, I primarily focus on the characteristics of international society and institutions rather than internal variables in order to examine the different paths toward democracy. Case studies on countries such as China, South Korea, and Iraq can help demonstrate that each type of international society as well as external and internal variables can have an impact on paths toward democracy. In the case of China, democratization can be viewed in the context of interest-oriented socialization. In South Korea, it can be viewed as value-oriented socialization, and, finally, in Iraq, it can be viewed as the use of force. To conclude, democracy is gradually becoming the post-Cold War and 21st century new standard of civilization and new wave expansion of international society, and each country\u27s path toward democracy is relatively different based on each circumstance