Quantum Vortices and Superconductivity + Challenge Answers | Space Time | PBS Digital Studios

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1. Hi, Matt,
   
   I'm curious how we might detect the remnants of another technologically advanced civilization within 100 LY of us. For instance, let's say 1 billion years ago, another civilization at approximately our current level of technology wiped itself out. Could we tell that they had once existed without leaving Earth?
2. I always click on these videos in hope of learning something. It always ends up with me leaving or sleeping 5 minutes in.
3. one huge factor this estimation is missing for "planets similar to earth" is the moon. In order for a planet to have seasons and stable weather, a planet MUST have at least one moon orbiting it in such a way and with such precise mass (relative to it's parent gravitational body) such that planetary oscillation is kept in check.
4. water freezing at above boiling point in carbon nanotubes is an interesting topological effect ,and not one I understand at all !
5. That equation for calculating number of tech civilizations is based on Earth like planets. But what about this: in a Solar system there are 6 presumed submerged oceans, under the thick crust of ice. That means that, approximately, there is 6 times more chance that submerged ocean planets or moons will produce life, than Earth-like planets.
6. well , your answer is incorrect. How can you generalize your local observation of a sample space ?!
7. The question isn't if there are aliens, it's WHEN.
   50,000 years ago aliens probably wouldn't have been that interested in us, and who knows if we'll even exist for another 1000.
   The universe is billions of years old, so the amount who have come and gone is virtually infinite, needless to say those who are still in their versions of monkey states, or haven't even begun to evolve yet.
8. I think the possibility of advanced life is far more unlikely than just life. using earth's history as a guide, life existed for billions of years (and developed early in earths history) but only recently humans became an advanced. So i think it's important to not assume it's just a matter of time for evolution to produce advance life. humans became advanced due to primarily the agricultural revolution which was a unique event. also technological advances may have only been possible due to unique human societal structure which other life may not possess - assuming life on other planets exist. There are other reason why advanced life may be much much rarer than just life - which is probably very rare as well.
9. what if an advanced population did not use detectable technology ie magnetic radiatian? also, we've only been detectable for a hundred years - nothing in the scheme of things
10. An advanced alien race wouldn't be foolish enough to create a cosmic signal lamp
11. What if the Tabby's star anomaly is the deteriorating remnant of a long-dead type II civ? Just because a civ is type II doesn't mean they'll survive eternally. Maybe their Dyson sphere, over the last couple of million years has deteriorated into a swarm of space junk around the star. Maybe the failed construction/collapse of the sphere was their civ's "great filter". I'd be interested in seeing a simulation of a non-functional mesh-network like Dyson sphere as it orbits its star over millions of years.
12. Will there be a video on the news from the EM Drive that NASA has been testing?? Apparently people are saying it works. A video explaining what it is and if its true would be great.
13. challenge question is irrelevant+math-math=
14. Could that explain the formation of a solar systems? As the nebula gets colder and colder, particles align to induce the spinning, formation of a gravitational center that will become the protosun by gathering mass... just wandering.
15. Jake A mentioned that we have had detectable radio/tv broadcasts for ~100 years. I would also suggest the newer technologies such as cable and the internet will mean that the total radio/tv leakage will slowly fade. So is ~50 or so, the Earth will become invisible again. The "window" of visibility will be very short indeed.
    
    Maybe we should look for other signatures for life. Street lighting will always be needed. Searching suitable planets that also show abnormal light spectra could be one. E.g. Sodium lines
16. Why not alien life not requiring water?
    Nor brains. Couldn't different base materials produce something utterly different?
    Otherwise, we're expecting something like the Star Wars cantina.
17. I think that we are by far the youngest civilization in 1000 light years. And we are known to all the others. But we are so ugly in their opinion that we are just getting ignored, because they're all jerks. So who needs 'em anyway.
18. I have a question, where does information / DNA come from? Even if all conditions were perfect with the exact right combination of chemicals etc. etc. Explain to me where the data would come from to create life?
19. Civilizations do not arise, Abiogenesis has been falsified numerous times by experiments such as the Urey and Miller experiment, speciation based on mutagenic alterations is also a falsified theory.
    
    I find it amazing that the more complex the universe and life becomes based on our empirical knowledge the more people believe it is self arising.
20. 4:12 Speak for yourself. Plus people like you who think they found the answer have closed minds.