Episode 1: Arrow of time will eventually lead to disorder. The cosmos, by guess, will became an empty space with light particles traveling and black holes. Black holes may stop existence. That might be the end of arrow of time. However, in micro-universe arrow of time can turn back.
Episode 2: All matters are constitute of 92 elements, forming by atoms. It's extremely difficut to bring two atoms together thus the elements with more atoms are more rare. Explosion comes when they are forced together. The origin of the elements are the expanding and fading of red giants which creates extreme high temprature and pressure to bring atoms together. However it will take supernorva to create elements heavier than iron. That's why elements like gold are so precious.
Episode 3: Gravity is matters bend the fabric of space-time with their weights and thus change the track of moving things. It's not simply a force. The heavier the matter is the more it will bend the space-time. This is what our best theory of space-time - Einstein's theory of general relatively tells us. In the deepest end of black hole, the space and time become infinitely curved that the center of the hole becomes infinitely dense. That place is called singularity, where our understanding of the cosmos ends.
Episode 4: All waves have speed limit. We can look back into time by observing stars far away from us due the the light speed. Messages are hidden in light itself. One of them is color. Lights can be stretched or squashed. We can suqash the light and reduce the wave length, then it moves towards the blue end of spectrum. If you stretch it and increase the wave length, everything moves towards the red end of spectrum. That is called "red shift". At the edge of the universe, all galaxies seems red. The lights are stretched and galaxies are further away from each other. This means the universe is expanding, all galaxies were on top of each other. That is the big bang theory.
The longest waves in the universe are radio waves. All objects give out radio waves. After we took a picture of the radio waves gave out since the big bang, we can see there are differences in density. It is the differences in density that gave birth to stars.
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