PBS Space Time

How Does The Nucleus Hold Together?

Two protons next to each other in an atomic nucleus are repelling each other electromagnetically with enough force to lift a medium-sized labradoodle off the ground. Release this energy and you have a nuclear explosion. So how does it all hold together? Nuclei are held together by a quirk of nature, without which we would have no complex atoms, no chemistry, and certainly no labradoodles.

How Does The Nucleus Hold Together?

14m 28s

  • How Eclipses Revealed Our Solar System: asset-mezzanine-16x9

    How Eclipses Revealed Our Solar System

    S10 E6 - 15m 7s

    Of all the astronomical phenomena you can witness, the total solar eclipse has to be the most visceral--the most in-your-face reminder that our reality consists of giant balls of rock spinning around stars. It's also the eclipse and phenomena like it that set us on the path to understanding that reality in the first place.

  • What If Gravity is Not A Fundamental Force?: asset-mezzanine-16x9

    What If Gravity is Not A Fundamental Force?

    S10 E5 - 15m 2s

    Gravity might not be a more fundamental than the force of a stretched elastic band. Maybe gravity is just an entropic byproduct—an emergent effect of the universe’s tendency to disorder. If you allow entropy to keep you in your seat for a bit, I’ll tell you all about it.

  • Does Space Emerge From A Holographic Boundary?: asset-mezzanine-16x9

    Does Space Emerge From A Holographic Boundary?

    S10 E4 - 14m 28s

    Space seems fundamental. Many physicists now think that the fabric of space emerges from something deeper. And the most existentially disturbing such proposal is that our 3-D universe is just the inward projection of an infinitely distant boundary. A hologram, or sorts. Let’s see how that can actually work, and what the holographic principle really says about the “realness” of this universe.

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