Ordinary matter makes up only a few percent of the content of the universe, almost a quarter of the content is made of dark matter and the rest is made of dark energy.Dark matter is hypothetical matter that is undetectable by its emitted radiation, but whose presence can be inferred from gravitational effects on visible matter.
In this video Patricia Burchat answers questions like:
What is universe made of?
What is the twenty first century view of the universe?
What are the laws of physics that govern the fundamental constituents of the universe?
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