Everything ever seen — every star, mountain, and face — makes up less than 5 percent of the universe. Astrophysicist Janna Levin reminds us that the rest — dark matter and dark energy — is invisible, mysterious, and everywhere. We are the luminous exception in a universe of darkness.

"Could black holes be the key to a quantum theory of gravity, a deeper theory of how reality, of how space and time works? Well, I think so."

"We're stuck at type zero. But what would it take to move between universes? What would it take to enter a black hole? What would it take to break the light barrier?"

“I like to say that physics is hard because physics is easy, by which I mean we actually think about physics as students.”

“Could black holes be the key to a quantum theory of gravity, a deeper theory of how reality, of how space and time works?”

"We are all in orbit around the center of the Milky Way galaxy. How big is this collection of stars? Somewhere between 200 and 400 billion suns in the Milky Way galaxy, about 100,000 light years across."

"Asking the question of, "Where did the entire universe come from?" is no longer a question for poets and theologians and philosophers. This is a question for scientists, and we have some amazing scientific answers to this question."

From nothing to everything: How zero changed our understanding of the universe, forever.

“You’re not meant to understand what I just said, because I don’t understand what I just said…” Physicist Brian Cox on one of the most complex theories in space science.

Is information intrinsic in our universe? NASA’s Michelle Thaller explains.

When black holes disappear, what happens to the stuff that fell in? Physicist Brian Cox explains.

Quantum wormholes are mathematically possible — but might also be physically impossible. Physicist Janna Levin explains Hawking’s famous information paradox.

Gravity defies quantum mechanics. What does that mean for a theory of everything?

Ever wonder what would happen if we got sucked into a black hole? Turns out we could live in it for a while — if it was big enough.

Sabine Hossenfelder talks about Albert Einstein, dead grandmothers, the physics of aging, and more in this full interview with Big Think.

According to renowned physicist Christophe Galfard, physics can’t explain our universe - yet.

Theoretical physicist Brian Greene explores the potential particles of time and why we could, in theory, travel forward in time but not back.

To understand the edges of our universe, we’ll need to explore the edges of our own philosophies.