Big Bang

What is the Cosmological Principle?

/ Emma / 8 Comments

What if I were to ask you: Are there any unique places in the universe?

That is, does any one location in the universe have a special vantage point? Does the universe look different from different locations?

You might say that yes, there are unique places, because everywhere you look in the night sky, there is something different. No two solar systems are the same, no two galaxies are quite the same, and on the scale of galaxy clusters, no cluster appears the same as the others.

But these are local variations.

Imagine if we could look into the universe from the outside. If we zoomed out until whole galaxy clusters appeared as little more than faint dots, we would see something quite different…

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The Universe’s First Moments

/ Emma / 6 Comments

Imagine a time before galaxies existed, before the first stars had been born, before the most basic building blocks of matter–atoms–had formed.

This was mere moments after the Big Bang.

No one understands how matter and energy behave under the extreme conditions of the Big Bang itself. We can’t tell the story of the universe from exactly zero. But we can rewind the clock all the way back to the universe’s first one-millionth of a second.

So, what was the universe like back then?

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What was the Big Bang?

/ Emma / 3 Comments

Have you heard of the Big Bang?

I still remember the first time I heard about it. I was little; I can’t remember if I’d fallen in love with astronomy yet. But I do remember sitting in my living room, surrounded by my dad’s scientific journals and magazines.

One cover page caught my eye. There was a full-page illustration of a young student standing before an old-fashioned blackboard, writing over and over, “I believe in the Big Bang.”

I had no idea back then what this “Big Bang” was.

And as it turns out, it’s not what most people think…

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