This theory could also mathematically explain and calculate the so-called Dark Energy, rather an unknown repulsing the universe force, as well. Following this direction, we could understand why, when and at what rate our universe expands or contracts.
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If there is gravity force between photons and matter with mass, there will be a simple and logical way to explain why the universe expands (so called Dark Energy) and at changing rates (Hubble Constant); and why the latest observations of the universe appear smoother than mainstream theory expected.
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If there is gravitational force between Electromagnetic waves and matter with mass, that would explain why the latest observations of the universe appear smoother than mainstream theory expected. Electromagnetic waves/Photons, which have gravitational effects, were emitted and spread throughout the entire universe. That makes the universe more even.
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According to a new study, there is gravitational force between matter with mass and photons, or between photons. Hence Photons/Electromagnetic waves in the outside space of universe exert gravitational force on the matter with mass and photons in the universe. This is the same as 3.1 how the gravity force inside a solid sphere. Inside the blue part the mass with matter gravity force will be calculated as, which is the reason on why the gravity force is less than the gravity force on the surface of the sphere.
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