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	2022-11-16: Are there Undiscovered Elements Beyond The Periodic Table? 16:34: In our last episode we talked about grabby aliens. 16:47: And the cut off is when the universe is fully colonized by … yep, grabby aliens. 16:34: In our last episode we talked about grabby aliens. 16:47: And the cut off is when the universe is fully colonized by … yep, grabby aliens.
	2022-11-09: What If Humanity Is Among The First Spacefaring Civilizations? 00:02: Half of the universe is filled with expansionist alien civilizations, and it’s only a matter of time before they’ll reach us. 03:14: And then they use the answer to propose something pretty wild: a proposal that gives their model its name: the grabby aliens model. 10:37: ... so-called grabby aliens model hypothesises the existence of a cosmic deadline for the birth of ... 11:01: The model claims that at some point in the future, all habitable planets will be occupied by rapidly expanding alien civilizations. 12:49: We do that with surprisingly useful bit of information: the fact that we haven’t yet seen any evidence of aliens through our telescopes. 13:08: ... if we could see grabby aliens in our skies, the aliens must be moving slowly, since they are in our ... 14:23: Finally: it tells us roughly when we should expect to meet those grabby aliens. 14:33: Don’t expect to meet any aliens any time soon, even if they do fill half the universe. 15:02: ... that our empty sky is one piece of evidence for a universe filled with aliens rushing in to grab this rare remaining patch of empty space ... 00:02: Half of the universe is filled with expansionist alien civilizations, and it’s only a matter of time before they’ll reach us. 11:01: The model claims that at some point in the future, all habitable planets will be occupied by rapidly expanding alien civilizations. 03:14: And then they use the answer to propose something pretty wild: a proposal that gives their model its name: the grabby aliens model. 10:37: ... so-called grabby aliens model hypothesises the existence of a cosmic deadline for the birth of ... 12:49: We do that with surprisingly useful bit of information: the fact that we haven’t yet seen any evidence of aliens through our telescopes. 13:08: ... if we could see grabby aliens in our skies, the aliens must be moving slowly, since they are in our ... 14:23: Finally: it tells us roughly when we should expect to meet those grabby aliens. 14:33: Don’t expect to meet any aliens any time soon, even if they do fill half the universe. 15:02: ... that our empty sky is one piece of evidence for a universe filled with aliens rushing in to grab this rare remaining patch of empty space ... 03:14: And then they use the answer to propose something pretty wild: a proposal that gives their model its name: the grabby aliens model. 10:37: ... so-called grabby aliens model hypothesises the existence of a cosmic deadline for the birth of new ... 15:02: ... that our empty sky is one piece of evidence for a universe filled with aliens rushing in to grab this rare remaining patch of empty space ...
	2022-10-12: The REAL Possibility of Mapping Alien Planets! 00:03: ... Pretty much anything. But definitely it could map the surfaces of alien ... 01:25: ... then we could start making detailed desk globes of alien worlds. Let’s talk about how we might   actually achieve this. ... 04:36: ... big part of my own research. But not today. Today we’re looking for aliens. ... 15:25: ... everyone in your immediate patch of Space Time know that it’s never aliens until it is at any rate.   There’s a link to the merch store ... 15:45: ... we’re going to have countless geographical features on alien worlds that’ll need naming.   We’ll try to get you guys a ... 00:03: ... Pretty much anything. But definitely it could map the surfaces of alien worlds. ... 01:25: ... then we could start making detailed desk globes of alien worlds. Let’s talk about how we might   actually achieve this. Because ... 15:45: ... we’re going to have countless geographical features on alien worlds that’ll need naming.   We’ll try to get you guys a ... 04:36: ... big part of my own research. But not today. Today we’re looking for aliens. ... 15:25: ... everyone in your immediate patch of Space Time know that it’s never aliens until it is at any rate.   There’s a link to the merch store ...
	2022-09-28: Why Is 1/137 One of the Greatest Unsolved Problems In Physics? 09:18: Imagine you were able to send a very short message to an alien civilization. 10:02: There’s no way for the alien civilization to recognize these numbers without knowing our units for distance, time, mass, electric charge, etc. 10:19: Even if you just transmit the number 137, those aliens are going to realize that something’s up. 09:18: Imagine you were able to send a very short message to an alien civilization. 10:02: There’s no way for the alien civilization to recognize these numbers without knowing our units for distance, time, mass, electric charge, etc. 10:19: Even if you just transmit the number 137, those aliens are going to realize that something’s up.
	2022-08-24: What Makes The Strong Force Strong? 21:07: ... trap as the proponents of theories of quantum consciousness, or that aliens built the pyramids, or that Elvis shot ...
	2022-07-20: What If We Live in a Superdeterministic Universe? 15:52: ... our last episode we talked about the challenges in decoding alien physics due to the hidden conventions that have been chosen arbitrarily ... 16:32: ... that a bigger problem than these conventions might be just the units the aliens are using - probably no such thing as centimeters or becquerels on ... 16:49: There are certain fundamental lengths, distances, energies, etc. that aliens could use to translate their units. 17:13: If the aliens simply describe the hydrogen atom and we saw that its electron had positive charge, we’d be set. 17:20: Dai Lixiuyuan and MrOvipare point out that we’d be able to tell what time "direction" the aliens use by their laws of thermodynamics. 17:45: ... fact these aliens would have to actually try to avoid revealing their physics conventions ... 18:07: ... as Benjamin Heasly points out, aliens would surely give some tests we could run to not risk planetary ... 15:52: ... our last episode we talked about the challenges in decoding alien physics due to the hidden conventions that have been chosen arbitrarily in order ... 16:32: ... that a bigger problem than these conventions might be just the units the aliens are using - probably no such thing as centimeters or becquerels on ... 16:49: There are certain fundamental lengths, distances, energies, etc. that aliens could use to translate their units. 17:13: If the aliens simply describe the hydrogen atom and we saw that its electron had positive charge, we’d be set. 17:20: Dai Lixiuyuan and MrOvipare point out that we’d be able to tell what time "direction" the aliens use by their laws of thermodynamics. 17:45: ... fact these aliens would have to actually try to avoid revealing their physics conventions ... 18:07: ... as Benjamin Heasly points out, aliens would surely give some tests we could run to not risk planetary ... 17:13: If the aliens simply describe the hydrogen atom and we saw that its electron had positive charge, we’d be set.
	2022-06-30: Could We Decode Alien Physics? 00:00: ... containing what amounts to all physics known by the aliens - including the equations of   their laws of physics and a ... 01:25: ... no. Unbeknownst to us, these aliens use positronic circuitry, not electronic. It’s just   ... 02:20: Is there anything in the way the aliens wrote down their laws of physics that might reveal our error? 05:20: ... describing   the laws of physics to determine the  alien sign convention for electric ... 05:33: ... to its antiparticle. So as long as our compendium   of alien physics describes the interactions  of specific particles, we can ... 06:55: ... made in our development of the laws of physics.   What if alien physics made other choices differently? Let's say that this rather ... 07:38: ... define particle handedness or partical chirality. What if our aliens were predominantly left-handed   or left tentacled or ... 10:41: ... left-handed antiparticles. If we search the   alien user manual for the part that describes weak force interactions we ... 11:52: ... and the final convention that we need to figure out is how the aliens define   the flow of time. Do they define the future as ... 14:09: ... Bryce, we realised it was selfish to just   sit waiting for aliens to send us their advanced technology, so we’ve used your ... 07:38: ... laws of physics. So can we figure out what parity convention our alien benefactors are using?   Well, only if we also know their sign convention. ... 00:00: ... We know  this because the particle carried by the   alien circuitry looks like the electron. We  decide this through a process of ... 01:25: ... a few cautious scientists take one last look  at the alien documentation. So what do you ... 00:00: ... blow up the planet.  How hard can it really be to decode  alien physics and engineering?   It’s gotta map to our own physics - I ... 05:33: ... to its antiparticle. So as long as our compendium   of alien physics describes the interactions  of specific particles, we can ... 06:55: ... made in our development of the laws of physics.   What if alien physics made other choices differently? Let's say that this rather finicky ... 05:33: ... to its antiparticle. So as long as our compendium   of alien physics describes the interactions  of specific particles, we can ... 05:20: ... describing   the laws of physics to determine the  alien sign convention for electric ... 00:00: ... the same universe after all.   We start by noticing that the alien technology seems to use good ol’ fashioned electronics,   even if it is ... 10:41: ... left-handed antiparticles. If we search the   alien user manual for the part that describes weak force interactions we ... 00:00: ... the same massive data   dump from what can only be an advanced alien species. It seems to contain the detailed   instructions for building a ... 01:25: ... no. Unbeknownst to us, these aliens use positronic circuitry, not electronic. It’s just   ... 02:20: Is there anything in the way the aliens wrote down their laws of physics that might reveal our error? 07:38: ... define particle handedness or partical chirality. What if our aliens were predominantly left-handed   or left tentacled or ... 10:41: ... we should be able to figure out   which handed rule the aliens are using. But again, this depends on our ability to distinguish ... 11:52: ... and the final convention that we need to figure out is how the aliens define   the flow of time. Do they define the future as ... 14:09: ... Bryce, we realised it was selfish to just   sit waiting for aliens to send us their advanced technology, so we’ve used your ... 00:00: ... containing what amounts to all physics known by the aliens - including the equations of   their laws of physics and a list ... 11:52: ... and the final convention that we need to figure out is how the aliens define   the flow of time. Do they define the future as an increasing ... 01:25: ... no. Unbeknownst to us, these aliens use positronic circuitry, not electronic. It’s just   that they define ... 02:20: Is there anything in the way the aliens wrote down their laws of physics that might reveal our error?
	2022-06-22: Is Interstellar Travel Impossible? 01:07: ... be the real answer to the Fermi paradox It’s the idea that we don’t see aliens because interstellar travel is just way too hard for anyone to ...
	2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life? 00:00: ... stellar systems. So is this why .. most of us .. haven’t seen aliens? ...
	2022-04-20: Does the Universe Create Itself? 17:39: ... explanation still isn’t that we’re in a black hole. And it’s not aliens or a simulation either. ...
	2022-03-08: Is the Proxima System Our Best Hope For Another Earth? 20:55: Or Aliens. And that's when our job will be done. 20:58: But let's hope it's never either. But  wait what if aliens are dark matter! 20:55: Or Aliens. And that's when our job will be done. 20:58: But let's hope it's never either. But  wait what if aliens are dark matter!
	2022-01-12: How To Simulate The Universe With DFT 14:43: ... and then the one about how we might search for Dyson spheres or other alien ... 18:30: So our aliens do have to shed their heat somehow. 18:43: Such a beam has a lower entropy than isotropic thermal radiation, and so less energy is made available for the aliens. 18:51: ... be doing just that. Defeshh points out that it’s scary to imagine an alien civilization that would need the amount of energy generated by a Dyson ... 19:04: ... completely agree. Especially if they're still scared of bigger aliens. Now the discussion that followed several people speculating on what ... 18:51: ... be doing just that. Defeshh points out that it’s scary to imagine an alien civilization that would need the amount of energy generated by a Dyson ... 14:43: ... and then the one about how we might search for Dyson spheres or other alien megastructures. ... 18:30: So our aliens do have to shed their heat somehow. 18:43: Such a beam has a lower entropy than isotropic thermal radiation, and so less energy is made available for the aliens. 19:04: ... completely agree. Especially if they're still scared of bigger aliens. Now the discussion that followed several people speculating on what ...
	2021-12-29: How to Find ALIEN Dyson Spheres 00:00: In our search for alien lifeforms we scan for primitive biosignatures, and wait and hope for their errant artificial signals to happen by the Earth. 05:40: So yeah, we could go flicking through the frequency channels of gas clouds looking for alien TV shows. 09:03: ... at the ends of their lives, or, presumably, when surrounded by giant alien astroengineering ... 10:47: Apparently there is non-Dyson-sphere-related weirdness going on, which may be interesting, but still isn’t aliens. 11:13: This weird star discovered by Tabetha Boyajian, exhibited complex dips in brightness, causing rumours of alien megastructures to abound. 13:40: The discovery of a single alien megastructure of any sort would massively change the way we think about our place in the universe. 09:03: ... at the ends of their lives, or, presumably, when surrounded by giant alien astroengineering ... 00:00: In our search for alien lifeforms we scan for primitive biosignatures, and wait and hope for their errant artificial signals to happen by the Earth. 13:40: The discovery of a single alien megastructure of any sort would massively change the way we think about our place in the universe. 11:13: This weird star discovered by Tabetha Boyajian, exhibited complex dips in brightness, causing rumours of alien megastructures to abound. 10:47: Apparently there is non-Dyson-sphere-related weirdness going on, which may be interesting, but still isn’t aliens.
	2021-12-10: 2021 End of Year AMA! 00:02: ... have been visited many times and it should be very apparent that aliens exist and so so how do i reconcile my uh instinct that we haven't ...
	2021-09-07: First Detection of Light from Behind a Black Hole 12:54: ... - as in, could we see the effects of FTL communication from distant alien ...
	2021-05-25: What If (Tiny) Black Holes Are Everywhere? 11:17: ... covering comments from the last two episodes: the one about how it’s not aliens yet, and then the one on how to mess with the limits of the uncertainty ... 11:28: You guys had a lot to say about the value of pursuing the “it’s aliens” hypothesis. 11:34: verus our partially facetious mantra that it's never aliens. I want to clarify my position on this. 11:38: I want it to be aliens. 11:42: And that’s what makes me most wary about the aliens hypothesis. 12:05: ... the case of the aliens hypothesis - this one is particularly dangerous because literally any ... 12:24: That said, as Simone Spinozi wittily queries: Aren't aliens also a natural phenomena? 12:41: ... saying “it’s never aliens” isn’t about “not having the courage” to pursue a fringe idea - it’s ... 15:45: Thanks - by these are just standard tricks used in film … by us space aliens. 11:17: ... covering comments from the last two episodes: the one about how it’s not aliens yet, and then the one on how to mess with the limits of the uncertainty ... 11:28: You guys had a lot to say about the value of pursuing the “it’s aliens” hypothesis. 11:34: verus our partially facetious mantra that it's never aliens. I want to clarify my position on this. 11:38: I want it to be aliens. 11:42: And that’s what makes me most wary about the aliens hypothesis. 12:05: ... the case of the aliens hypothesis - this one is particularly dangerous because literally any ... 12:24: That said, as Simone Spinozi wittily queries: Aren't aliens also a natural phenomena? 12:41: ... saying “it’s never aliens” isn’t about “not having the courage” to pursue a fringe idea - it’s ... 15:45: Thanks - by these are just standard tricks used in film … by us space aliens. 11:28: You guys had a lot to say about the value of pursuing the “it’s aliens” hypothesis. 11:42: And that’s what makes me most wary about the aliens hypothesis. 12:05: ... the case of the aliens hypothesis - this one is particularly dangerous because literally any unexplained ... 12:41: ... saying “it’s never aliens” isn’t about “not having the courage” to pursue a fringe idea - it’s about ... 12:05: ... phenomenon can be fit into some version of the extreme high-tech aliens story. ... 12:41: ... idea - it’s about absolute scientific rigor so that when it really is aliens you’ll know you did your due diligence and can have any faith whatever your ...
	2021-05-11: How To Know If It's Aliens 00:00: ... follow one rule on Space Time: It’s never aliens. But every rule has an exception and this rule is no exception because: ... 01:24: ... last half century we get another tantalizing hint of the existence of alien life. But they all seem to fizzle out - at least, we never get the grand ... 04:11: ... - but they don’t need to. When we’re talking about the discovery of alien life, the burden of proof rests very heavily on the shoulders of the ... 04:45: ... - or at least be very cautious about - all prior claims of evidence of alien life. For example, the occasional spikes in methane detected by the ... 06:27: ... to his many claims that some new astrophysical phenomenon might be aliens. And the statement is logically correct - improbable does beat impossible ... 09:21: ... by Tabitha Boyajian. Some declared that it’s best explained by an alien megastructure eclipsing the star’s light. That claim was on the strength ... 09:58: ... so all of this is a bit of a bummer if you really want it to be aliens. Let’s get to some hints that don’t yet have satisfactory natural ... 11:24: ... star. Now there are very good reasons to think that this signal isn't aliens. For example, Proxima is a dangerously active red dwarf - it’s unlikely ... 12:35: ... seen before. So does this mean we can never conclude the existence of aliens based on any observation? Should we not even bother looking? Not at all. ... 13:10: ... of us is - When do we believe some new hint or claim of the detection of alien life? That’s easier to answer - optimistic skepticism is the way to go. ... 13:52: ... reward we're going to reveal to you the true secrets of all those alien communications that astronomers have been hiding from the public for ... 06:27: ... that the most likely explanation for Oumuamua is that it’s an alien artifact - in particular a light sail - probably a broken one. Now, we covered ... 13:52: ... reward we're going to reveal to you the true secrets of all those alien communications that astronomers have been hiding from the public for years. We'll then ... 06:27: ... of Oumuamua and a clarification that there are huge problems with the alien hypothesis. But why not aliens if there’s no accepted natural explanation? Well the ... 01:24: ... last half century we get another tantalizing hint of the existence of alien life. But they all seem to fizzle out - at least, we never get the grand ... 04:11: ... - but they don’t need to. When we’re talking about the discovery of alien life, the burden of proof rests very heavily on the shoulders of the ... 04:45: ... - or at least be very cautious about - all prior claims of evidence of alien life. For example, the occasional spikes in methane detected by the Curiosity ... 13:10: ... of us is - When do we believe some new hint or claim of the detection of alien life? That’s easier to answer - optimistic skepticism is the way to go. ... 09:21: ... by Tabitha Boyajian. Some declared that it’s best explained by an alien megastructure eclipsing the star’s light. That claim was on the strength that no known ... 00:00: ... follow one rule on Space Time: It’s never aliens. But every rule has an exception and this rule is no exception because: ... 01:24: ... we never get the grand announcement that THIS particular evidence of aliens turns out to be ... 06:27: ... to his many claims that some new astrophysical phenomenon might be aliens. And the statement is logically correct - improbable does beat impossible ... 09:58: ... so all of this is a bit of a bummer if you really want it to be aliens. Let’s get to some hints that don’t yet have satisfactory natural ... 11:24: ... star. Now there are very good reasons to think that this signal isn't aliens. For example, Proxima is a dangerously active red dwarf - it’s unlikely ... 12:35: ... seen before. So does this mean we can never conclude the existence of aliens based on any observation? Should we not even bother looking? Not at all. ... 13:10: ... to answer - optimistic skepticism is the way to go. Believe me, if it is aliens the evidence will mount. Most scientists do want it to be aliens more ... 11:24: ... or is a natural source that we don’t know about yet. Or it could be aliens - but no one’s claiming aliens just ... 12:35: ... seen before. So does this mean we can never conclude the existence of aliens based on any observation? Should we not even bother looking? Not at all. I ... 01:24: ... we never get the grand announcement that THIS particular evidence of aliens turns out to be ...
	2021-03-09: How Does Gravity Affect Light? 02:36: I dunno, to escape giant alien spiders or something. 03:22: Your laser’s power rating goes from kill to tickle - good news for the giant alien spider, not so much for you. 03:39: That for some reason is also being attacked by giant alien spiders. 05:13: Let’s start with the good-old equivalence principle again, and a spaceship attacked by giant alien spiders. 05:45: These giant alien spiders are no joke. 03:22: Your laser’s power rating goes from kill to tickle - good news for the giant alien spider, not so much for you. 02:36: I dunno, to escape giant alien spiders or something. 03:39: That for some reason is also being attacked by giant alien spiders. 05:13: Let’s start with the good-old equivalence principle again, and a spaceship attacked by giant alien spiders. 05:45: These giant alien spiders are no joke.
	2020-10-05: Venus May Have Life! 00:11: In fact we may have detected the signature of alien life - Venusian life -for the first time. 00:47: I joked more that the weirdest end to this very weird year would be the discovery of alien life. 03:15: These guys speculated about both microbes and larger creatures, alien gas bags perhaps supported by in-built hydrogen balloons. 07:41: Honestly, the former still seems the more likely because, well, it’s never aliens until every other possibility is ruled out. 12:15: The discovery of alien life in our nearest planetary neighbor would totally change our calculations about the frequency of life in the universe. 03:15: These guys speculated about both microbes and larger creatures, alien gas bags perhaps supported by in-built hydrogen balloons. 00:11: In fact we may have detected the signature of alien life - Venusian life -for the first time. 00:47: I joked more that the weirdest end to this very weird year would be the discovery of alien life. 12:15: The discovery of alien life in our nearest planetary neighbor would totally change our calculations about the frequency of life in the universe. 00:11: In fact we may have detected the signature of alien life - Venusian life -for the first time. 07:41: Honestly, the former still seems the more likely because, well, it’s never aliens until every other possibility is ruled out.
	2020-06-15: What Happens After the Universe Ends? 15:47: I had pointed out that alien viruses would need to be DNA-based in order to infect DNA-based life. 16:14: ... no reason to believe that alien DNA would have evolved exactly the same code Alien viruses would have no ... 16:56: Devin Smith asks what protocols exist for protecting earth from alien microbes, should they be discovered on a mission - say, to Mars. 17:30: And if it was actually alien life? 17:44: ... Stark realizes we can have an asteroid impact and alien virus wrapped up in one convenient single apocalypse, and asks that we ... 16:14: ... no reason to believe that alien DNA would have evolved exactly the same code Alien viruses would have no way ... 17:30: And if it was actually alien life? 16:56: Devin Smith asks what protocols exist for protecting earth from alien microbes, should they be discovered on a mission - say, to Mars. 17:44: ... Stark realizes we can have an asteroid impact and alien virus wrapped up in one convenient single apocalypse, and asks that we stop ... 15:47: I had pointed out that alien viruses would need to be DNA-based in order to infect DNA-based life. 16:14: ... to believe that alien DNA would have evolved exactly the same code Alien viruses would have no way to deliver their demands - for example replicate me or ...
	2020-06-08: Can Viruses Travel Between Planets? 04:32: ... of the most promising prospects for our first detection of alien life is to find signatures of its chemical activity in the atmospheres ... 04:43: ... talked about how this is done before - but in short, when an alien world passes in front of its home star, we can see signatures ... 05:32: So the evidence of alien viruses is unlikely to come to us. 11:16: But are such alien lurgies really a possible danger? 11:50: Would alien viruses have evolved to attack the same genetic structure? 12:14: But it’s very likely that an alien virus that made its way to earth would find it had absolutely no way to attack the cells it finds here. 12:27: Could any of the past recent pandemics have resulted from alien viruses? 12:59: It’s never aliens if there’s a sensible earthly explanation. 04:32: ... of the most promising prospects for our first detection of alien life is to find signatures of its chemical activity in the atmospheres of ... 11:16: But are such alien lurgies really a possible danger? 12:14: But it’s very likely that an alien virus that made its way to earth would find it had absolutely no way to attack the cells it finds here. 05:32: So the evidence of alien viruses is unlikely to come to us. 11:50: Would alien viruses have evolved to attack the same genetic structure? 12:27: Could any of the past recent pandemics have resulted from alien viruses? 04:32: ... is to find signatures of its chemical activity in the atmospheres of alien worlds. ... 12:59: It’s never aliens if there’s a sensible earthly explanation.
	2020-02-18: Does Consciousness Influence Quantum Mechanics? 00:36: The rules governing the tiny quantum world of atoms and photons seem alien.
	2019-11-04: Why We Might Be Alone in the Universe 01:44: When combined with the apparent absence of alien civilizations, it may tell us that intelligent life is incredibly rare in our universe. 03:00: Or, rather, a lack thereof - the fact that we see no evidence for aliens. 01:44: When combined with the apparent absence of alien civilizations, it may tell us that intelligent life is incredibly rare in our universe. 03:00: Or, rather, a lack thereof - the fact that we see no evidence for aliens.
	2019-10-07: Black Hole Harmonics 13:12: ... you want to know the number of possible multiverses or the likelihood of aliens, to challenge yourself in the advanced levels of science you’re going to ...
	2019-09-30: How Many Universes Are There? 00:14: And most importantly, what can they tell us about aliens? 08:54: It may explain why we don’t see aliens. 11:09: Ergo we shouldn’t be surprised that we don’t see aliens. 00:14: And most importantly, what can they tell us about aliens? 08:54: It may explain why we don’t see aliens. 11:09: Ergo we shouldn’t be surprised that we don’t see aliens.
	2019-08-12: Exploring Arecibo in VR 180 03:24: ... the planet habitability laboratory about finding exoplanets talking to aliens and Arecibo role in all of that. You can follow this link for that ...
	2019-07-25: Deciphering The Vast Scale of the Universe 09:44: ... watch Joe Hanson explore how to calculate the possibility that advanced alien civilizations are out ...
	2018-12-12: Quantum Physics in a Mirror Universe 00:02: ... of years but spores may be able to Estelle Lea proposes that we become aliens who originated life across the galaxy by sending lights-out probes ...
	2018-12-06: Did Life on Earth Come from Space? 00:37: ... technological civilizations far in advance of us and speaking of aliens a fun version of this idea is directed panspermia in which the seeds of ...
	2018-11-21: 'Oumuamua Is Not Aliens 00:07: To repeat the "Space Time" maxim, it's never aliens, until it is. 01:15: ... Biali and Avi Loeb that investigates the possibility that Oumuamua is aliens, or more accurately an artificial light cell presumably attached to an ... 02:46: Those things are odd, but not odd enough to start assuming aliens. 04:00: So duh, aliens, right? 04:06: To be fair, in the paper itself, these authors don't say it's aliens or even that it's probably aliens. 04:58: ... thinner and lighter than any conceivable natural space object, ergo aliens. ... 05:49: What if aliens sent this probe to us intentionally? 09:45: Can we really say the same about the unnatural explanation of an alien lightsail? 10:43: ... that travels at such a snail's pace, surely beyond the lifespan of any aliens who sent it, especially when the technology to accelerate a Lightsail to ... 11:10: In their paper, they don't claim that an alien lightsail is the most likely explanation, just that it's a plausible one. 11:53: Some of those articles were measured and some were even critical, but most were giddy at the possibility that we discovered an alien craft. 12:04: Harvard astrophysicist blah blah blah alien probe. 12:22: The author responses in media interviews do not downplay the likelihood of aliens. 12:59: Whether or not it's aliens, it's likely our first encounter with the natural or unnatural denizens from interstellar space time. 11:53: Some of those articles were measured and some were even critical, but most were giddy at the possibility that we discovered an alien craft. 09:45: Can we really say the same about the unnatural explanation of an alien lightsail? 11:10: In their paper, they don't claim that an alien lightsail is the most likely explanation, just that it's a plausible one. 01:15: ... or more accurately an artificial light cell presumably attached to an alien probe. ... 12:04: Harvard astrophysicist blah blah blah alien probe. 00:07: To repeat the "Space Time" maxim, it's never aliens, until it is. 01:15: ... Biali and Avi Loeb that investigates the possibility that Oumuamua is aliens, or more accurately an artificial light cell presumably attached to an ... 02:46: Those things are odd, but not odd enough to start assuming aliens. 04:00: So duh, aliens, right? 04:06: To be fair, in the paper itself, these authors don't say it's aliens or even that it's probably aliens. 04:58: ... thinner and lighter than any conceivable natural space object, ergo aliens. ... 05:49: What if aliens sent this probe to us intentionally? 10:43: ... that travels at such a snail's pace, surely beyond the lifespan of any aliens who sent it, especially when the technology to accelerate a Lightsail to ... 12:22: The author responses in media interviews do not downplay the likelihood of aliens. 12:59: Whether or not it's aliens, it's likely our first encounter with the natural or unnatural denizens from interstellar space time.
	2018-10-31: Are Virtual Particles A New Layer of Reality? 13:43: ... conclusions we can really draw about this persistently annoying lack of aliens. ... 13:54: ... even paradoxical with some common objections about the behavior of aliens, saying things like the window of strong radio emission for any ... 14:57: All of these arguments of aliens probably don't do this or that are what we call a soft filter. 15:11: These arguments on alien psychology are soft filters. 13:43: ... conclusions we can really draw about this persistently annoying lack of aliens. ... 13:54: ... even paradoxical with some common objections about the behavior of aliens, saying things like the window of strong radio emission for any ... 14:57: All of these arguments of aliens probably don't do this or that are what we call a soft filter.
	2018-10-25: Will We Ever Find Alien Life? 00:13: But our most recent surveys of the Milky Way finally allow us to draw scientific conclusions about this depressingly persistent absence of aliens. 00:54: If aliens can travel between the stars, why haven't they visited? 01:43: ... Kepler telescope has discovered 2,652 alien worlds to date, spotted as they marched across the face of their parent ... 04:14: Thrillingly, one proposed explanation was an alien mega structure, perhaps a vast fleet of solar collectors built by the local inhabitants. 04:38: As we like to say on Space Time, it's never aliens until it is. 04:46: For example, these alien solar collectors may be our best shot at spotting other civilizations. 09:00: ... researchers estimate that in order for us not to see any aliens, the chance of going from space rock to high tech society must be less ... 09:17: ... it's gamma ray bursts or something else, our failure to find aliens tells us there must be a developmental bottleneck, or colloquially, a ... 09:37: That is perhaps it's one of the biological factors of the Drake equation that keeps the number of aliens low. 10:43: Some scientists have been inspired by the persistent absence of evidence for aliens to investigate this possibility. 04:14: Thrillingly, one proposed explanation was an alien mega structure, perhaps a vast fleet of solar collectors built by the local inhabitants. 04:46: For example, these alien solar collectors may be our best shot at spotting other civilizations. 01:43: ... Kepler telescope has discovered 2,652 alien worlds to date, spotted as they marched across the face of their parent star in ... 00:13: But our most recent surveys of the Milky Way finally allow us to draw scientific conclusions about this depressingly persistent absence of aliens. 00:54: If aliens can travel between the stars, why haven't they visited? 04:38: As we like to say on Space Time, it's never aliens until it is. 09:00: ... researchers estimate that in order for us not to see any aliens, the chance of going from space rock to high tech society must be less ... 09:17: ... it's gamma ray bursts or something else, our failure to find aliens tells us there must be a developmental bottleneck, or colloquially, a ... 09:37: That is perhaps it's one of the biological factors of the Drake equation that keeps the number of aliens low. 10:43: Some scientists have been inspired by the persistent absence of evidence for aliens to investigate this possibility. 09:37: That is perhaps it's one of the biological factors of the Drake equation that keeps the number of aliens low. 09:17: ... it's gamma ray bursts or something else, our failure to find aliens tells us there must be a developmental bottleneck, or colloquially, a great ...
	2018-08-30: Is There Life on Mars? 04:56: Then he went full-on "Ancient Aliens," Martian edition. 08:05: It's never aliens until there's no other possible explanation. 04:56: Then he went full-on "Ancient Aliens," Martian edition. 08:05: It's never aliens until there's no other possible explanation. 04:56: Then he went full-on "Ancient Aliens," Martian edition.
	2018-01-10: What Do Stars Sound Like? 07:39: While Kepler does asteroseismology as a side gig to finding alien planets.
	2017-12-13: The Origin of 'Oumuamua, Our First Interstellar Visitor 02:46: Or it could be the flickering exhaust jets of an alien scout ship returning to report a planet ripe for invasion. 02:53: But no, it's never aliens. 06:02: Unless of course there are aliens in that solar system throwing rocks at us? 06:06: No, it's never aliens. 02:46: Or it could be the flickering exhaust jets of an alien scout ship returning to report a planet ripe for invasion. 02:53: But no, it's never aliens. 06:02: Unless of course there are aliens in that solar system throwing rocks at us? 06:06: No, it's never aliens.
	2017-12-06: Understanding the Uncertainty Principle with Quantum Fourier Series 13:13: ... stars for the characteristic dips in brightness due to transiting alien ... 13:23: Sukuraslight suggested that Seti@home use its computing cycles to mine bitcoin instead of look for alien signals. 13:13: ... stars for the characteristic dips in brightness due to transiting alien planets. ... 13:23: Sukuraslight suggested that Seti@home use its computing cycles to mine bitcoin instead of look for alien signals.
	2017-11-22: Suicide Space Robots 03:26: But this time, the alien atmosphere proved the savior, rather than the destroyer of robots.
	2017-08-24: First Detection of Life 01:35: ... easiest-- and so probably the first-- way we'll spot alien life is by its effect on its planet's atmosphere-- in particular, the ... 03:24: It's never aliens until it's aliens. 04:05: Yep, Carl Sagan published a nature paper about how to detect alien cow farts. 04:42: Alien life might have very different chemistry and so result in other disequilibria. 04:58: There is one molecule that we want to find in high abundance regardless of alien chemistry or even equilibrium values-- we want to find liquid water. 06:17: Now these wouldn't be considered proof of life on an alien world, but maybe a strong indicator, especially in the presence of atmospheric signatures. 09:03: ... for the first time to perform Sagan's 1990 experiment on an Earth-like alien ... 09:52: Perhaps our first detection of alien life is only a couple of years away. 10:08: Our first evidence of it is likely to be found in the disequilibria of alien atmospheres. 10:19: In fact, we may even discover alien life in the next few years. 10:08: Our first evidence of it is likely to be found in the disequilibria of alien atmospheres. 04:58: There is one molecule that we want to find in high abundance regardless of alien chemistry or even equilibrium values-- we want to find liquid water. 04:05: Yep, Carl Sagan published a nature paper about how to detect alien cow farts. 01:35: ... easiest-- and so probably the first-- way we'll spot alien life is by its effect on its planet's atmosphere-- in particular, the ... 04:42: Alien life might have very different chemistry and so result in other disequilibria. 09:52: Perhaps our first detection of alien life is only a couple of years away. 10:19: In fact, we may even discover alien life in the next few years. 03:24: It's never aliens until it's aliens.
	2017-05-03: Are We Living in an Ancestor Simulation? ft. Neil deGrasse Tyson 01:07: ... snot-nosed kid in the parents' basement of an alien civilization, who's bored, and they're more advanced than we are, and ... 03:11: Now Neil uses an entertaining example of us being a Sims game for hyper advanced alien basement dwellers. 01:07: ... snot-nosed kid in the parents' basement of an alien civilization, who's bored, and they're more advanced than we are, and they have way ...
	2017-01-25: Why Quasars are so Awesome 03:37: ... flurry of hypothesizing followed-- swarms of neutron stars, an alien civilization harnessing their entire galaxy's power, bright, fast-moving ...
	2017-01-11: The EM Drive: Fact or Fantasy? 09:56: So in our recent episode, we talked about whether alien civilizations could possibly detect us from radio transmissions. 11:09: SunPower Guru argues that SITI is pointless, because there's no good reason to think that aliens would use, for example, radio. 11:17: Well, actually, there are good reasons to think that alien civilizations will use similar technologies to us. 11:39: It's common to draw analogies between technological or intellectual gaps, like we are to aliens as ants are to us or similar. 12:22: There's very good reason to think that aliens will use light, with a radio or otherwise. 12:28: Speaking of not using radio, Richy Rich and Gareth Dean had a nice discussion on whether aliens would use radio waves. 13:48: ... is confident that we'll first make contact with an alien civilization by discovering some form of universal internet based on ... 14:14: He suggests that the first message we get from aliens might be stop broadcasting. 13:48: ... is confident that we'll first make contact with an alien civilization by discovering some form of universal internet based on ... 09:56: So in our recent episode, we talked about whether alien civilizations could possibly detect us from radio transmissions. 11:17: Well, actually, there are good reasons to think that alien civilizations will use similar technologies to us. 11:09: SunPower Guru argues that SITI is pointless, because there's no good reason to think that aliens would use, for example, radio. 11:39: It's common to draw analogies between technological or intellectual gaps, like we are to aliens as ants are to us or similar. 12:22: There's very good reason to think that aliens will use light, with a radio or otherwise. 12:28: Speaking of not using radio, Richy Rich and Gareth Dean had a nice discussion on whether aliens would use radio waves. 14:14: He suggests that the first message we get from aliens might be stop broadcasting.
	2017-01-04: How to See Black Holes + Kugelblitz Challenge Answer 04:59: An extremely advanced alien race has decided to destroy the Earth by enveloping it in a giant Kugelblitz, a black hole made entirely of lights. 10:53: Maybe we can just build a mini sun inside after we blast the aliens and save spacetime. 04:59: An extremely advanced alien race has decided to destroy the Earth by enveloping it in a giant Kugelblitz, a black hole made entirely of lights. 10:53: Maybe we can just build a mini sun inside after we blast the aliens and save spacetime.
	2016-12-21: Have They Seen Us? 00:16: What are the chances that alien civilizations have detected and even decoded these signals? 00:31: ... advanced alien race monitoring our planet, even from the nearest neighboring star, ... 02:05: ... aliens arrive on our doorstep tomorrow, would they have been alerted to our ... 03:03: Surely, this is the window where aliens would choose to broadcast their messages welcoming us into the galactic community. 03:54: ... been successful if there were deliberate powerful beacons emitted by an alien ... 04:41: An alien civilization at exactly our current tech level would never have seen our TV bubble. 05:18: This is another advantage for searching for alien signals in and around the water hole. 05:52: But surely aliens are working with the same physics that we are. 06:38: ... an interferometer facility with the sensitivity to potentially see an alien TV bubble to many light years and that is large enough to filter out ... 07:28: The SKA is not being built to search for aliens. 08:18: Such a machine also just happens to be perfect for spotting alien television bubbles. 09:17: An alien civilization with their own SKA certainly couldn't watch Earth TV. 10:04: ... aliens would need a radio telescope trillions of times the SKA's surface area ... 10:25: We may even be a little optimistic in thinking that the SKA will detect alien TV. 11:33: ... Earth's TV bubble would be spotted within hours, or even minutes, of aliens pointing the facility to our solar system, even if they weren't looking ... 03:54: ... been successful if there were deliberate powerful beacons emitted by an alien civilization. ... 04:41: An alien civilization at exactly our current tech level would never have seen our TV bubble. 09:17: An alien civilization with their own SKA certainly couldn't watch Earth TV. 00:16: What are the chances that alien civilizations have detected and even decoded these signals? 00:31: ... advanced alien race monitoring our planet, even from the nearest neighboring star, would ... 05:18: This is another advantage for searching for alien signals in and around the water hole. 08:18: Such a machine also just happens to be perfect for spotting alien television bubbles. 02:05: ... aliens arrive on our doorstep tomorrow, would they have been alerted to our ... 03:03: Surely, this is the window where aliens would choose to broadcast their messages welcoming us into the galactic community. 05:52: But surely aliens are working with the same physics that we are. 07:28: The SKA is not being built to search for aliens. 10:04: ... aliens would need a radio telescope trillions of times the SKA's surface area ... 11:33: ... Earth's TV bubble would be spotted within hours, or even minutes, of aliens pointing the facility to our solar system, even if they weren't looking ... 02:05: ... aliens arrive on our doorstep tomorrow, would they have been alerted to our presence ... 11:33: ... Earth's TV bubble would be spotted within hours, or even minutes, of aliens pointing the facility to our solar system, even if they weren't looking for ...
	2016-12-14: Escape The Kugelblitz Challenge 01:00: And then we'll use this knowledge to address a very serious, although questionably plausible, scenario involving an alien black hole attack. 04:10: Scenario-- a super-advanced alien civilization decides to build a giant black hole that will engulf the planet Earth. 06:14: Maybe that energy can then power a super weapon to fight the aliens. 06:46: Maybe the outgoing light wave will destroy the alien ships. 01:00: And then we'll use this knowledge to address a very serious, although questionably plausible, scenario involving an alien black hole attack. 04:10: Scenario-- a super-advanced alien civilization decides to build a giant black hole that will engulf the planet Earth. 06:46: Maybe the outgoing light wave will destroy the alien ships. 06:14: Maybe that energy can then power a super weapon to fight the aliens.
	2016-11-02: Quantum Vortices and Superconductivity + Drake Equation Challenge Answers 08:23: Ergo, Tabby's Star probably isn't aliens. Sorry!
	2016-10-05: Are We Alone? Galactic Civilization Challenge 05:22: Some people like to think this is evidence of some sort of alien mega structure eclipsing the star.
	2016-09-29: Life on Europa? 07:23: ... are blasting enough energy and nutrients upwards to support all those alien whale things and tentacled monstrosities and merperson cities that I ...
	2016-09-14: Self-Replicating Robots and Galactic Domination 00:06: Space is big, maybe even too big to be easily colonized by real, living aliens. 05:55: ... system, or build a Dyson swarm, or annihilate all life-- whatever these aliens are ... 07:23: Let's talk about numbers before we get into the intricacies of alien psychology. 08:17: OK, so alien psychology-- the exclusivity argument, that civilizations will never do certain things, is fatally flawed. 07:23: Let's talk about numbers before we get into the intricacies of alien psychology. 08:17: OK, so alien psychology-- the exclusivity argument, that civilizations will never do certain things, is fatally flawed. 00:06: Space is big, maybe even too big to be easily colonized by real, living aliens. 05:55: ... system, or build a Dyson swarm, or annihilate all life-- whatever these aliens are ...
	2016-08-24: Should We Build a Dyson Sphere? 09:26: Aliens build partial swarms to provide the energy to build more efficient engines, which would be essentially undetectable. 10:00: It's never aliens, unless every other explanation is exhausted. 09:26: Aliens build partial swarms to provide the energy to build more efficient engines, which would be essentially undetectable. 10:00: It's never aliens, unless every other explanation is exhausted. 09:26: Aliens build partial swarms to provide the energy to build more efficient engines, which would be essentially undetectable.
	2016-05-04: Will Starshot's Insterstellar Journey Succeed? 00:49: To send swarms of light sail driven nanocraft to Alpha Centauri fast enough that we may have close-up images of alien worlds within our lifetimes. 04:51: So less vast alien mega structure slash planet destroyer and more Bond super-villain laser. 08:35: ... be sure to get back to you with the first up close alien snapshots in around 50 years right here on "Space Time." In the last ... 04:51: So less vast alien mega structure slash planet destroyer and more Bond super-villain laser. 08:35: ... be sure to get back to you with the first up close alien snapshots in around 50 years right here on "Space Time." In the last episode, we ... 00:49: To send swarms of light sail driven nanocraft to Alpha Centauri fast enough that we may have close-up images of alien worlds within our lifetimes.
	2015-11-05: Why Haven't We Found Alien Life? 00:10: [MUSIC PLAYING] Why don't we see alien civilizations? 00:22: But today we'd like to go deeper because it really does seem like there should be aliens. 08:04: But this just makes it weirder that the Milky Way isn't swarming with ancient alien civilizations. 11:23: Now, a few of you took issue with my statement that it's never aliens. 11:27: And fair enough, it's never aliens until it's aliens. 11:31: ... point of this philosophy is that the alien hypothesis is a bad place to start because you can explains almost any ... 00:10: [MUSIC PLAYING] Why don't we see alien civilizations? 08:04: But this just makes it weirder that the Milky Way isn't swarming with ancient alien civilizations. 11:31: ... point of this philosophy is that the alien hypothesis is a bad place to start because you can explains almost any weird ... 00:22: But today we'd like to go deeper because it really does seem like there should be aliens. 11:23: Now, a few of you took issue with my statement that it's never aliens. 11:27: And fair enough, it's never aliens until it's aliens.
	2015-10-28: Is The Alcubierre Warp Drive Possible? 08:49: ... Kepler Space Telescope result that the media is hyping that there's an alien megastructure eclipsing a distance ... 08:57: Now, this is a stunning result. But as we say on "Space Time," it's never aliens. 09:24: Although I imagine it could possibly be insanely vast ragtag colony of space structures surrounding a parent planet== except it's never aliens. 09:37: ... Un Disclosed, I say, you laugh, but the first evidence of alien life may be the spectroscopic signature of biogenetic atmospheric ... 08:49: ... Kepler Space Telescope result that the media is hyping that there's an alien megastructure eclipsing a distance ... 08:57: Now, this is a stunning result. But as we say on "Space Time," it's never aliens. 09:24: Although I imagine it could possibly be insanely vast ragtag colony of space structures surrounding a parent planet== except it's never aliens.
	2015-08-05: What Physics Teachers Get Wrong About Tides! 09:49: ... down in the description, you'll see a link to her talk about alien atmospheres-- it's very good-- at the NASA Space Apps Challenge, along ...
	2015-06-24: The Calendar, Australia & White Christmas 06:04: ... Time." Last week we talked about different possible ways to signal aliens, including maybe putting planet-sized geometric objects in orbit around ... 06:16: ... McLean asked, "if aliens can't pick up our radio waves, then why are we trying to listen for ... 06:27: And the operating assumption of SETI for several decades is that maybe aliens are broadcasting such a beacon into space. 06:32: However, they might be using optical laser pulses if they have limited resources or the kind of alien billboards that we discussed in the episode. 06:16: ... can't pick up our radio waves, then why are we trying to listen for alien radio waves with SETI?" Well, aliens wouldn't be able to pick up our stray ... 06:04: ... Time." Last week we talked about different possible ways to signal aliens, including maybe putting planet-sized geometric objects in orbit around ... 06:16: ... McLean asked, "if aliens can't pick up our radio waves, then why are we trying to listen for ... 06:27: And the operating assumption of SETI for several decades is that maybe aliens are broadcasting such a beacon into space. 06:04: ... Time." Last week we talked about different possible ways to signal aliens, including maybe putting planet-sized geometric objects in orbit around the ...
	2015-06-17: How to Signal Aliens 00:02: Aliens. 00:13: [THEME MUSIC] Let's leave aside for the moment the fact that signaling aliens might not be a good idea. 00:39: It's too slow, it's too hard to do in bulk, and it's too relying on aliens being able to decipher the content of the probe. 00:50: ... to popular misconception, it could be very difficult for aliens to pick up the radio and TV transmissions that we've been leaking into ... 00:58: ... growing consensus is that, even if nearby aliens have space-based radio receivers with the total area equivalent to a ... 05:07: So to signal aliens very far away near the galactic center, you'd still need high-powered microwaves. 05:12: ... in all, a billboard seems like a distinct, cheap, ongoing signal that aliens could notice just by doing exoplanets astronomy, even if they aren't ... 05:24: ... that billboards are the most efficient, most noticeable way to signal aliens, or at least one of them, that aliens might apply Princess Bride poison ... 05:40: In which case, in order to catch our attention, maybe alien have put up billboards. 05:55: ... pulses, which SETI does now, should SETI also be looking for geometric alien billboards orbiting nearby ... 00:02: Aliens. 00:13: [THEME MUSIC] Let's leave aside for the moment the fact that signaling aliens might not be a good idea. 00:39: It's too slow, it's too hard to do in bulk, and it's too relying on aliens being able to decipher the content of the probe. 00:50: ... to popular misconception, it could be very difficult for aliens to pick up the radio and TV transmissions that we've been leaking into ... 00:58: ... growing consensus is that, even if nearby aliens have space-based radio receivers with the total area equivalent to a ... 05:07: So to signal aliens very far away near the galactic center, you'd still need high-powered microwaves. 05:12: ... in all, a billboard seems like a distinct, cheap, ongoing signal that aliens could notice just by doing exoplanets astronomy, even if they aren't ... 05:24: ... that billboards are the most efficient, most noticeable way to signal aliens, or at least one of them, that aliens might apply Princess Bride poison ...
	2015-05-27: Habitable Exoplanets Debunked! 07:10: ... true, if aliens came along with some spaceships and lowered down some cranes and lifted ...
	2015-04-29: What's the Most Realistic Artificial Gravity in Sci-Fi? 00:35: ... "Battlestar Galactica," "Star Trek," "Andromeda," the Ridley Scott "Alien," "Prometheus" series, all of them use this ...
	2015-03-25: Cosmic Microwave Background Explained 00:59: Aliens. 01:01: No, it's not aliens. 01:02: It's never aliens. 00:59: Aliens. 01:01: No, it's not aliens. 01:02: It's never aliens.
	2015-02-25: How Do You Measure the Size of the Universe? 05:32: ... "Space Time." Last week, we asked whether it's irrational to believe in aliens? ... 06:20: So why should all the aliens? 05:32: ... "Space Time." Last week, we asked whether it's irrational to believe in aliens? ... 06:20: So why should all the aliens?
	2015-02-18: Is It Irrational to Believe in Aliens? 00:00: [MUSIC PLAYING] A lot of people, including many scientists, seem pretty confident that aliens have to exist somewhere in the universe. 00:09: Is that just wishful thinking or can you actually calculate whether intelligent aliens exist? 00:19: ... sightings and Area 51 rumors aside, we have never seen an alien, never heard an alien, or had any kind of verifiable indication that ... 00:27: So how do you estimate how many intelligent aliens you should see when you've never actually seen any? 01:19: The details are different, since Drake, the founder of SETI, was estimating the number of detectable alien radio signals. 01:48: Is it impossible to take a rational statistical scientific position on whether or not aliens exist? 01:54: There are sensible arguments both for and against the existence of aliens. 02:07: Let's start with a pro aliens argument, that intelligent life should exist. 02:35: You would still expect over 1,000 alien civilizations in our galaxy by now. 03:15: The Sagan view then is not that alien life is guaranteed. 03:29: One prominent no aliens argument begins by pointing out that our galaxy is not just very big, but also very old, about 10 billion years old. 04:17: ... space station probes, a broken down Millenium Falcon, I don't know, an alien "drink Pepsi" sign, ... 04:32: We've see exactly zero evidence of current intelligent aliens or residual evidence s extinct ones. 04:37: ... if our ability to send stuff into space isn't special, and alien intelligence really is inevitable on the billions and billions of ... 04:54: The punchline is that precisely because we don't see aliens, the odds of intelligent life must be, wait for it, astronomically low. 05:07: Maybe aliens hate exploring space, OK. 05:39: ... intelligent alien life never evolves on the billions of possible planets or that ... 06:40: Anyway, now you know how legit scientists and scholars handle the question of space aliens. 06:50: Alien abduction story, also welcomed, with proof. 02:35: You would still expect over 1,000 alien civilizations in our galaxy by now. 04:17: ... space station probes, a broken down Millenium Falcon, I don't know, an alien "drink Pepsi" sign, ... 04:37: ... if our ability to send stuff into space isn't special, and alien intelligence really is inevitable on the billions and billions of habitable planets, ... 03:15: The Sagan view then is not that alien life is guaranteed. 05:39: ... intelligent alien life never evolves on the billions of possible planets or that intelligent ... 01:19: The details are different, since Drake, the founder of SETI, was estimating the number of detectable alien radio signals. 00:00: [MUSIC PLAYING] A lot of people, including many scientists, seem pretty confident that aliens have to exist somewhere in the universe. 00:09: Is that just wishful thinking or can you actually calculate whether intelligent aliens exist? 00:27: So how do you estimate how many intelligent aliens you should see when you've never actually seen any? 01:48: Is it impossible to take a rational statistical scientific position on whether or not aliens exist? 01:54: There are sensible arguments both for and against the existence of aliens. 02:07: Let's start with a pro aliens argument, that intelligent life should exist. 03:29: One prominent no aliens argument begins by pointing out that our galaxy is not just very big, but also very old, about 10 billion years old. 04:32: We've see exactly zero evidence of current intelligent aliens or residual evidence s extinct ones. 04:37: ... on the billions and billions of habitable planets, then where the aliens? ... 04:54: The punchline is that precisely because we don't see aliens, the odds of intelligent life must be, wait for it, astronomically low. 05:07: Maybe aliens hate exploring space, OK. 05:39: ... never evolves on the billions of possible planets or that intelligent aliens evolve, none of whom ever spread out in any observable way in the ... 06:40: Anyway, now you know how legit scientists and scholars handle the question of space aliens. 02:07: Let's start with a pro aliens argument, that intelligent life should exist. 03:29: One prominent no aliens argument begins by pointing out that our galaxy is not just very big, but also very old, about 10 billion years old. 05:39: ... never evolves on the billions of possible planets or that intelligent aliens evolve, none of whom ever spread out in any observable way in the ... 00:09: Is that just wishful thinking or can you actually calculate whether intelligent aliens exist? 01:48: Is it impossible to take a rational statistical scientific position on whether or not aliens exist? 05:07: Maybe aliens hate exploring space, OK.

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