PBS Space Time

Dark Forest: Should We Not Contact Aliens?

In 1974 we sent the Arecibo radio message towards Messier 13. The message was mostly symbolic; we weren’t really expecting a reply. Yet surely other civilisations out there are doing the same thing. So, why haven’t we heard anything? What if the silence from the stars is a hint that we shouldn’t be so outgoing? What if aliens are deliberately keeping quiet for fear that they might be destroyed?

Dark Forest: Should We Not Contact Aliens?

14m 12s

  • Does Infinity - Infinity = an Electron: asset-mezzanine-16x9

    Does Infinity - Infinity = an Electron

    S10 E30 - 15m 35s

    What do you get if you take something that’s infinitely massive and combining with something else that’s negative infinitely massive? You get a single electron, at least that’s what it looks like in our most precise way of describing the quantum world.

  • What Does An Electron Actually Look Like?: asset-mezzanine-16x9

    What Does An Electron Actually Look Like?

    S10 E29 - 13m 39s

    What does an electron really look like? I mean, if we zoom in all the way. Is it a sizeless speck of charge? Is it a multidimensional vortex of quantum strangeness? Is it the boundary of a tiny universe with universe-electrons of its own? Let’s find out.

  • The NEW Ultimate Energy Limit of the Universe: asset-mezzanine-16x9

    The NEW Ultimate Energy Limit of the Universe

    S10 E28 - 16m 35s

    The James Webb Space Telescope has found a quasar that simultaneously breaks a century-old theoretical limit and may explain the conundrum of gigantic black holes in the early universe.

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