Science and Nature

PBS Space Time

PBS Space Time explores the outer reaches of space, the craziness of astrophysics, the possibilities of sci-fi, and anything else you can think of beyond Planet Earth. Host Matt O'Dowd breaks down both the basic and incredibly complex sides of space and time.

Hawking Radiation


It’s the most famous prediction of perhaps the most famous genius of our time ... Stephen Hawking's theory of Hawking Radiation.


  • Does Antimatter Create Anti-Gravity?: asset-mezzanine-16x9

    Does Antimatter Create Anti-Gravity?

    S9 E35 - 16m 30s

    For many years, physicists have wondered whether a certain well-known exotic material may experience gravitational repulsion from the Earth. That material is antimatter, and physicists at CERN have just completed a very long and very difficult experiment to answer a seemingly simple question: does antimatter fall down, or does it fall up?

  • Can The Crisis in Cosmology Be Solved With Cosmic Voids?: asset-mezzanine-16x9

    Can The Crisis in Cosmology Be Solved With Cosmic Voids?

    S9 E34 - 14m 29s

    Two of the greatest mysteries in cosmology are the nature of dark energy and the apparent conflict in our measurements of the expansion rate of the early versus the modern universe that even dark energy can’t account for. Could both of these be explained by looking to a part of the universe that we’ve largely ignored so far? Could cosmic voids be driving the universe?

  • What If There's A Black Hole Inside The Sun?: asset-mezzanine-16x9

    What If There's A Black Hole Inside The Sun?

    S9 E33 - 17m 53s

    A fun nightmare sci-fi scenario is the sun being consumed by a black hole. Fortunately the chance of a black hole randomly wandering into our solar system is pretty tiny. That’s good news. But what if it’s already here, hiding in the core of the Sun and slowly eating it from the inside out?

  • What if Humans Are Not Earth's First Civilization?: asset-mezzanine-16x9

    What if Humans Are Not Earth's First Civilization?

    S9 E32 - 19m 19s

    We’re almost certainly the first technological civilization on Earth. But what if we’re not? We are. Although how sure are we, really? The Silurian hypothesis, which asks whether pre-human industrial civilizations might have existed.

  • Does Many Worlds Explain Quantum Probabilities?: asset-mezzanine-16x9

    Does Many Worlds Explain Quantum Probabilities?

    S9 E31 - 19m 3s

    The mystery of what happens when we go from a superposition to a definite state is known as the Measurement Problem. The different interpretations of quantum mechanics are really about solving the measurement problem. But Many Worlds offers one thing that the other interpretations do not: there’s no collapse of the wavefunction - which might be the key to solving the measurement problem?

  • What If Gravity is Not Quantum?: asset-mezzanine-16x9

    What If Gravity is Not Quantum?

    S9 E30 - 18m 32s

    The holy grail of theoretical physics is to come up with a quantum theory of gravity. But after a century of trying we really have no idea how close we are, or it it's even possible. But we shouldn't feel bad because it turns out that the universe is doing everything it its power to make this as difficult as possible. Or it's telling us that it isn't. Should we take the hint?

  • How Will We (Most Likely) Discover Alien Life?: asset-mezzanine-16x9

    How Will We (Most Likely) Discover Alien Life?

    S9 E29 - 18m 32s

    The first discovery of extraterrestrial life will almost certainly NOT be when it visits us, nor when we visit it. It’ll be in the excruciatingly faint changes in the color of alien sunsets glimpsed hundreds of light years away. Today we’re going to talk about the first such hint, why it's probably not aliens, and why there’s a tiny chance that it still might not not be aliens.

  • Why Did Attosecond Physics Win the Nobel Prize?: asset-mezzanine-16x9

    Why Did Attosecond Physics Win the Nobel Prize?

    S9 E28 - 12m 5s

    The 2023 Nobel prize in physics has been awarded to three physicists for opening a new window in physics—but it's not a window to a new size scale or a new mode of seeing—-it’s for a new window in time. It’s for attosecond physics—the billionth of a billionth of a second that represents the timescale of the insides of atoms. This year’s Nobel in physics is for a microscope in time.

  • JWST Discovered The Farthest Star Ever Seen!: asset-mezzanine-16x9

    JWST Discovered The Farthest Star Ever Seen!

    S9 E27 - 15m 59s

    With the James Webb Space Telescope we’re starting to be able to see the first galaxies. If only we could see the individual stars in those galaxies we could learn so much more. Well, now using this one weird trick we can do exactly that. Or at least we have one lonely star at the end of the universe. But it won’t be lonely for long.

  • Are Many Worlds & Pilot Wave The Same Theory?: asset-mezzanine-16x9

    Are Many Worlds & Pilot Wave The Same Theory?

    S9 E26 - 17m 24s

    It’s hard to interpret the strange results of quantum mechanics, though many have tried. Interpretations range from the outlandish—like the multiple universes of Many Worlds, to the almost mundane, like the very mechanical Pilot Wave Theory. But perhaps we’re converging on an answer, because some are arguing that these two interpretations are really the same thing.

  • Are Room Temperature Superconductors Impossible?: asset-mezzanine-16x9

    Are Room Temperature Superconductors Impossible?

    S9 E25 - 18m

    The broader use of superconductors is limited because they need to be cooled to extremely low temperatures to work. But what if we could produce superconductivity at room temperature? It would change the world.

  • What New Science Would We Discover with a Moon Telescope?: asset-mezzanine-16x9

    What New Science Would We Discover with a Moon Telescope?

    S9 E24 - 20m 39s

    There’s nowhere on the earth, or even orbiting the Earth, that’s far enough to hear to the faint radio hum from the time before stars. In fact, we may need to build a giant radio telescope in the quietest place in the solar system—the far side of the moon.

Extras + Features

  • Quantum Physics in a Mirror Universe: asset-mezzanine-16x9

    Quantum Physics in a Mirror Universe

    S5 - 12m 19s

    When you look in mirror, and see what you think is a perfect reflection, you might be looking at universe whose laws are fundamentally different.

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