The Universe was created 13.7 billion years ago in the Big Bang. Astronomers expect that first generation stars were formed, within the expanding universe. After that galaxies and star clusters were formed. Our solar system was born about 9 billion years after the Big Bang. A few 100 Million years later, life on earth was born. The history of the Human race is only few million years old. Modern particle physics and astrophysics have allowed us to explain cosmic history including the origin of matter and the formation of stars and galaxies from observing electromagnetic waves directly with state of the art detectors. In these first 10 years of the 21st century, newly developed detectors will revolutionaries our whole view of the Universe.
In this article I will summarize some of the key issues in the history of the universe with a particular emphasis on the formation of globular clusters, as a fossil of the universe, in low-heavy-element environments.

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Direct numerical simulations of natural convection in differentially heated vertical channel are conducted with Boussinesq approximation. The discritization of computation is carried out with a spectral method for three directions. Rayleigh number (Ra) which is defined with the channel width and the temperature difference between both walls, is 5.4 × 10⁴. We extract the large-scale structures by using Snapshot POD (Proper Orthogonal Decomposition) and trace the time evolution of the structures. The formation and the breakdown of the large-scale streaky structures are observed sequentially in one cycle, suggesting that the regeneration process of the large scale flow is similar to the case of a minimal plane Couette flow. Also it is found that the strong down-wash event, due to the large scale vortical flow, play a key role for the heat transfer on the wall.

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It is shown that Rosby wave and Kelvin wave can be converted into each other at a boundary in a rotating shallow water system using numerical experiments. This conversion makes it possible that Rossby wave pass through an island in the transient process of an initial value problem. In the steady state, it makes difference on flow resistance between two basin connected by a channel according to its latitude. This property of the waves can affect the 3-D circulation such as the thermohaline circulation of the ocean not only 2-D flow.

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