The Universe

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We have not directly observed dark energy or dark matter, but scientists think they exist because they are the simplest explanations for two otherwise unexplained behaviors: the accelerating expansion of the universe and the mass that appears to be missing in galaxies based on gravitational effects

In other words, dark energy makes the universe expand faster and faster, and dark matter makes galaxies have the shapes that they do

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How will the universe end?

Big Freeze?

üThis is currently the most accepted theory within the scientific community.

üDark energy will cause the universe to expand forever and become very cold as the stars burn out

Big Crunch?

üThis theory says that the density of the universe is enough for gravity to stop its expansion and begin contracting

üAfter billions of years of contracting, the universe could “crunch” into a single point, possibly causing another Big Bang

üThis “bang-crunch” cycle could occur repeatedly

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The anthropic principle

Scientists have discovered that in order for humans to exist, many extremely unlikely events must have occurred, but they did…

Are we incredibly lucky to exist? Yes and no.

The anthropic principle basically says that because we can consider this question, we must have been made, so its not really luck, but necessity

Basically, “an observed universe must allow the observer to exist"

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We still don’t know:

What caused the Big Bang?

What is dark matter?

What is dark energy?

Are there other universes connected to ours?

Why is there something instead of nothing?

And many other questions…