Our lives are so rushed, so busy. Always on the clock. Counting the hours, minutes, seconds. Have you ever stopped to wonder: what are you counting? What is this thing, that’s all around us, invisible, inescapable, always running out? What is time?

Original Air Date: November 18, 2023

Interviews In This Hour:

Time, loss and the Big Bang — Finding solace in the vastness of space — Carlo Rovelli's white holes, where time dissolves

Guests:

Marcelo Gleiser, Marjolijn van Heemstra, Carlo Rovelli

Check out the full series at ttbook.org/deeptime

Deep Time: The Cosmos and Us

”To the Best of Our Knowledge” is a Peabody award-winning national public radio show that explores big ideas and beautiful questions. Deep interviews with philosophers, writers, artists, scientists, historians, and others help listeners find new sources of meaning, purpose, and wonder in daily life. Whether it’s about bees, poetry, skin, or psychedelics, every episode is an intimate, sound-rich journey into open-minded, open-hearted conversations. Warm and engaging, TTBOOK helps listeners feel less alone and more connected – to our common humanity and to the world we share.

For more from the TTBOOK team, visit us at ttbook.org.

Society & Culture

Personal Journals

History

Philosophy

Places & Travel

We get the message before we’re out of training pants – when the going gets tough, look on the bright side, make lemonade out of lemons and just do it. We’re gonna consider the exact opposite – the wisdom of giving up and letting go. Because sometimes, the strongest and most courageous thing you can do is walk away.

Original Air Date: April 27, 2024

Interviews In This Hour:

The power and boundary-breaking of fasting — How do we know when to call it quits? — Escaping the tyranny of certainty

Guests:

John Oakes, Adam Phillips, Maggie Jackson

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Giving Up

Are you ready to think in centuries instead of seconds? Eons instead of hours? It’s time to make thousand-year plans and appreciate how Earth keeps time. 

Original Air Date: August 19, 2023

Interviews In This Hour:

Shifting your mind to 'geologic' time — Discovering the wonders of ancient cave art — Making art inspired by the ancestors

Guests:

Marcia Bjornerud, Stephen Alvarez, Dustin Illetewahke Mater

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Deep Time: How Earth Keeps Time

Can neuroscience explain what happens to the brain on psychedelics? And even if we map the brain while it’s tripping, does that tell us why these experiences can be so transformative? 

We’ll talk with some of the pioneers in psychedelic research — from Amanda Feilding’s boundary-busting work to Robin Carhart-Harris’ theory of the "entropic brain." Also, renowned neuroscientist Christof Koch goes down the rabbit hole on 5-MeO-DMT, also known as toad venom.  

Original Air Date: July 15, 2023

Interviews In This Hour:

Exploring consciousness on toad venom — The godmother of the European psychedelic revival — How therapeutic psilocybin could help heal long-buried trauma — Magic mushrooms and the 'entropic brain'

Guests:

Christof Koch, Amanda Feilding, David Nutt, Robin Carhart-Harris

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Luminous: Your Brain on Shrooms

From our narrow vantage point on Earth, how can we see what's out there, beyond our skies? We look to how scientists and scholars have studied eclipses, dark matter, deep-space transmissions from intelligent life and more, all in the hopes of painting a clearer picture of a vast and invisible universe.

Original Air Date: August 19, 2017

Interviews In This Hour:

How Eclipse Chasing Inspires Generations of Scientists — How Do We Investigate The Invisible Parts of the Universe? — Search For Life In All The Wrong Places — What Can You Hear In Space? — The Universe Is Under No Obligation To Make Sense To Us

Guests:

David Baron, Priya Natarajan, Seth Shostak, Don Gurnett, Neil deGrasse Tyson

Further Reading:

NASA: 2024 Eclipse Explorer

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Total Eclipse and Other Wonders

AI can do amazing things – write your term papers, sequence your genes, maybe replace your therapist. But even super-intelligence has limits. So, does AI really have a mind — or a soul? We'll explore the frontiers of artificial intelligence — from robots painting masterpieces to software engineers trying to create god-like machines.

Original Air Date: March 30, 2024

Interviews In This Hour:

Stop worrying about deepfakes — Does AI have a soul? — Can robots paint a masterpiece?

Guests:

Walter Scheirer, Meghan O’Gieblyn, Sougwen 愫君 Chung

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Deep Time: The Cosmos and Us

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