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Our mission is to answer the biggest questions of all, scientifically.
What is the Universe made of? How did it become the way it is today? Where did everything come from? What is the ultimate fate of the cosmos?
For most of human history, these questions had no clear answers. Today, they do. Starts With a Bang, written by Dr. Ethan Siegel, explores what we know about the universe and how we came to know it, bringing the latest discoveries in cosmology and astrophysics directly to you.
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Ethan Siegel is an award-winning PhD astrophysicist and the author of four books, including The Grand Cosmic Story, published by National Geographic.
Ask Ethan: Could evolving dark energy lead to a Big Crunch?
There's some, but not overwhelming, evidence that dark energy is evolving. What would it take for a "Big Crunch" to be our cosmic fate?
Our Universe requires dark matter in order to make sense of things, astrophysically. Could massive photons do the trick?
Practically all of the matter we see and interact with is made of atoms, which are mostly empty space. Then why is reality so… solid?
If the electromagnetic and weak forces unify to make the electroweak force, maybe, at higher energies, something even grander happens?
The Universe is expanding, and the Hubble constant tells us how fast. But how can it be a constant if the expansion is accelerating?
In all the Universe, only a few particles are eternally stable. The photon, the quantum of light, has an infinite lifetime. Or does it?
Yes, the Universe is expanding, but if you've ever wondered, "How fast is it expanding," the answer isn't in terms of a speed at all.
Is the Universe finite or infinite? Does it go on forever or loop back on itself? Here's what would happen if you traveled forever.