Katie Mack

Theoretical cosmologist and Hawking Chair in Cosmology and Science Communication at the Perimeter Institute for Theoretical Physics; author of The End of Everything (Astrophysically Speaking) and a TED Fellow whose work explores dark matter, the early universe, and the fate of the cosmos.

The Universe Will End, and Meaning Must Exist Now

Cosmologist Katie Mack argues that the universe’s eventual end offers no final accounting that can make human life meaningful in retrospect. In conversation with designer and podcaster Debbie Millman, Mack describes five broad cosmic fates physicists have modeled—from collapse and heat death to vacuum decay and cyclic rebirth—while explaining how the cosmic microwave background preserves a direct trace of the early universe. Her conclusion is personal as well as scientific: for temporary beings in a changing cosmos, meaning must exist in the present rather than await a cosmic resolution.

TEDAug 24, 20267 min read