Gravity / Quantum Physics / Quantum Physics


What Is Dark Energy?

In 1998, astronomers hoped to discover whether the universe would expand forever or eventually collapse under its own gravity. What they found instead shattered every expectation: something was overpowering the pull of gravity and pushing the universe apart.

They called it dark energy. But what is this invisible substance that makes up more than 70% of our universe? And what does it mean for the future?

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Greg Kestin

    Greg Kestin holds a faculty position at Harvard University, where he conducts theoretical physics research, teaches, and produces educational online content. He earned his physics Ph.D. from Harvard, as a member of The Center for the Fundamental Laws of Nature, focusing on theoretical particle physics and quantum field theory. Over his career, he has also conducted research in nuclear physics, fusion energy, and gravitational wave physics. For over a decade he has been involved with innovative educational outreach endeavors, bringing science to both students and members of the public through his writings, videos, lectures, and multimedia.

    Samia Bouzid

    Samia Bouzid is a multimedia storyteller with a passion for science, especially physics. She is a production assistant for NOVA’s YouTube series “What the Physics?!”