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Maybe the Earth was not spinning faster and slowing down now. What if the Earth was smaller, this could also account for the shorter days?
Hamza - you are confusing space with the Earth's atmosphere.
just because an object is in a vacuum, doesnt mean it cant be slowed down. electromagnetic forces act over a distance.
I mentioned a can of worms; if the Earth were to suddenly change its gravity without a corresponding quantity of mass, the edifice upon which our scientific understanding of how gravity works must be flawed, or at the very least may have missed something important.
Indeed - and your question opens a can of worms. Here a rough animation I made that looks at two Earth/time scenarios:http://goodfelloweb.com/nature/terra/terra.htmlIt is curious that the gross behavior of continents is to drift apart rather remain in equilibrium or clump together.
The supercontinent cycle describes the quasi-periodic aggregration and dispersal of Earth's continental crust. There are varying opinions as to whether Earth's budget of continental crust is increasing, decreasing, or remaining about constant, but it is agreed that this inventory is constantly being reconfigured. Continental collision makes fewer and larger continents while rifting makes more and smaller continents. The last supercontinent, Pangaea, formed about 300 million years ago. The previous supercontinent, Pannotia or Greater Gondwanaland, formed about 600 million years ago, and its dispersal formed the fragments that ultimately collided to form Pangaea. But beyond this the time span between supercontinents becomes more irregular. For example, the supercontinent before Gondwanaland, Rodinia, existed ~1.1 billion to ~750 million years ago - a mere 150 million years before Gondwanaland. The supercontinent before this was Columbia: ~1.8 to 1.5 billion years ago. And before this was Kenorland: ~2.7 to ~2.1 billion years ago. Ur existed ~3 billion years ago and Vaalbara ~3.6 to ~2.8 billion years ago. One complete Supercontinent cycle is said to take 300 to 500 million years to occur.The hypothetical supercontinent cycle is, in some ways, the complement to the Wilson cycle. The latter is named after plate tectonics pioneer J. Tuzo Wilson and describes the periodic opening and closing of ocean basins. Because the oldest seafloor is only 170 million years old, whereas the oldest bit of continental crust goes back to 4 billion years or more, it makes sense to emphasize the much longer record of the planetary pulse that is recorded in the continents.