Condensed Sets on Compact Hausdorff Spaces

A condensed set is a sheaf on the site of Stone spaces and continuous maps. We prove that condensed sets are equivalent to sheaves on the site of compact Hausdorff spaces and continuous maps. As an application, we show that there exists a model structure on the category of condensed sets.Comment: 15 page

Japanese national pension scheme and economic growth

This thesis is an exercise to apply macro-economic analysis to the Japanese National Pension Scheme. Though this treats the effect of the National Pension Scheme on the national economy, the analysis is limited to its impact on national expenditure and on economic growth. Other important aspects, such as in¬ come redistribution, are not considered, though a short reference is made to the built-in stabilizing effectiveness of the pension scheme. I have concentrated on the problem of growth because of its importance in the case of the Japanese economy. I shall try to demonstrate the impact of the new National Pension Scheme on future economic growth and this requires me to examine the special features of the institutional framework of the Japanese National Pension Scheme in so far as it may affect the structure of government investment. In analysing the effect of the Scheme, some of the analytical tools of macro-economics, such as the Keynesian income determina¬ tion model, a growth model of a Harrod-Domar type, etc., are used. In analysing the effects on national expenditure only the direction of changes in expenditure produced by the Scheme are indicated. Given present information,an econometric model would not seem to be appropriate. In essence, this is an analysis of the pension scheme, yet several important traditional topics of social security are considered because they form the background to a study of pensions. Although a short statistical and historical description of the place of social services in the economy is given, historical details are not the main concern of the present thesis. Administrative details of the financing of the Scheme are not provided, although considerable space is given in the analysis to the structural framework of the Japanese pension scheme

Seasonal variation of moisture transport in polar regions and the relation with annular modes

Climatological seasonal variations of moisture transport and the interannual variations associated with the annular modes in the Arctic and Antarctic regions are investigated using 15-year ECMWF reanalysis data. Over the Arctic, there are strong moisture inflows from the Atlantic and Pacific in all seasons. Over the Antarctic, a strong moisture inflow exists around the Antarctic Peninsula in all seasons and another strong inflow exists over the Bellingshausen Sea and the Amundsen Sea in austral autumn and winter. Transient moisture flux is dominant over stationary flux and transient flux variation mainly controls the seasonal variation of precipitation minus evaporation(P-E) in both regions. The seasonal variations of P-E show a summer maximum in the Arctic and a winter maximum in the Antarctic. It is mainly governed by the seasonal variation of precipitable water variation in the Arctic and transient eddy activity in the Antarctic. The zonal mean poleward and eastward moisture fluxes in high latitudes are positively correlated with annular modes in both regions. Positive polarity of the Arctic Oscillation is associated with enhanced moisture inflow from the Atlantic, while positive polarity of the Antarctic Oscillation is associated with enhanced moisture inflow west of the Antarctic Peninsula

Atmospheric hydrological cycles in the Arctic and Antarctic during the past four decades

Atmospheric hydrological cycles over the Arctic and Antarctic have been investigated in the previous studies and there are some similarity and dissimilarity in the two polar regions. The Arctic and Antarctic are areas of moisture flux convergence through the year. So the precipitation (P) exceeds the evaporation (E) and the net precipitation (P-E) is positive. Therefore, the atmospheric moisture transport is a primary input of water into the polar regions. Meanwhile the climatological seasonal cycles of P-E over these regions are dominated by transient moisture flux associated with cyclone activities, the interannual variations are governed by the stationary flux associated with the Arctic Oscillation and the Antarctic Oscillation (AAO). In addition, recent climate changes influence the polar hydrological cycles. Our analyses using an atmospheric reanalysis up to recent years indicated that there were no significant long-term changes in the poleward moisture transport into both the Arctic and Antarctic during 1979-2016. On the other hand, the water vapor (precipitable water) were clearly increasing over the Arctic and gradually decreasing over the Antarctic during the same period. As expected, the increasing trend of water vapor was due to the large warming over the Arctic. There were two reasons for the gradually decreasing trend of water vapor over the Antarctic. The first one was the positive trend of AAO in summer and the second was deepening trend of the Amundsen low in autumn. The trends in water vapor and temperature during the past 38 years further suggest that both polar regions were getting dryer in several seasons. The trend, however, needs to be confirmed by follow-up climatological analyses

Quantum magnonics: magnon meets superconducting qubit

The techniques of microwave quantum optics are applied to collective spin excitations in a macroscopic sphere of ferromagnetic insulator. We demonstrate, in the single-magnon limit, strong coupling between a magnetostatic mode in the sphere and a microwave cavity mode. Moreover, we introduce a superconducting qubit in the cavity and couple the qubit with the magnon excitation via the virtual photon excitation. We observe the magnon-vacuum-induced Rabi splitting. The hybrid quantum system enables generation and characterization of non-classical quantum states of magnons.Comment: 10 pages, 6 figure