I saw a UFO once. I was eight or nine, playing in the street with a friend who was a couple of years older, and we saw a featureless silver disc hovering over the houses. We watched it for a few seconds, and then it shot away incredibly quickly. Even as a kid, I got angry it was ignoring the laws of physics. We ran inside to tell the grown-ups, and they were skeptical -- you'd be skeptical too, right? I got my own back a few years later: one of those grown-ups told me, "Last night I saw a flying saucer. I was coming out of the pub after a few drinks." I stopped him there. I said, "I can explain that sighting."
Nekoč sem videl NLP. Star sem bil osem ali devet let, s prijateljem, ki je bil nekaj let starejši, sem se igral na ulici in videla sva pust srebrn disk, ki je lebdel nad hišami. Nekaj sekund sva ga gledala, nato pa se je neverjetno hitro izstrelil stran. Celo kot otroka me je jezilo, ker je ignoriral vse fizikalne zakone. Stekla sva noter, da bi povedala odraslim, in bili so skeptični ... Tudi vi bi bili skeptični, kajne? Nekaj let kasneje sem bil tudi jaz. Eden od tistih odraslih mi je rekel: "Sinoči sem videl NLP. Vračal sem se iz gostilne po nekaj kozarčkih." Ustavil sem ga in rekel: "To videnje pa lahko razložim."
(Laughter)
(smeh)
Psychologists have shown we can't trust our brains to tell the truth. It's easy to fool ourselves. I saw something, but what's more likely -- that I saw an alien spacecraft, or that my brain misinterpreted the data my eyes were giving it? Ever since though I've wondered: Why don't we see flying saucers flitting around? At the very least, why don't we see life out there in the cosmos? It's a puzzle, and I've discussed it with dozens of experts from different disciplines over the past three decades. And there's no consensus. Frank Drake began searching for alien signals back in 1960 -- so far, nothing. And with each passing year, this nonobservation, this lack of evidence for any alien activity gets more puzzling because we should see them, shouldn't we?
Psihologi so pokazali, da možganom ne moremo zaupati, da nam bodo povedali resnico. Z lahkoto nas preslepijo. Nekaj sem videl, ampak kaj je bolj verjetno: da sem videl neznano plovilo ali da so moji možgani napačno interpretirali podatke, ki so jim jih poslale moje oči? Pa vendar se od takrat sprašujem, zakaj okoli sebe ne vidimo švigati letečih krožnikov? Zakaj vsaj ne vidimo življenja tam zunaj v kozmosu? To je uganka, o kateri v zadnjih treh desetletjih diskutiramo z na desetine strokovnjaki z različnih področij. In ne pridemo do soglasja. Frank Drake je začel že leta 1960 iskati nezemljanske signale, pa do danes - nič. In z vsakim minulim letom ta nezasleditev, to pomanjkanje dokazov nezemeljske aktivnosti postane bolj begajoče, ker bi jih vendar morali videti, kajne?
The universe is 13.8 billion years old, give or take. If we represent the age of the universe by one year, then our species came into being about 12 minutes before midnight, 31st December. Western civilization has existed for a few seconds. Extraterrestrial civilizations could have started in the summer months. Imagine a summer civilization developing a level of technology more advanced than ours, but tech based on accepted physics though, I'm not talking wormholes or warp drives -- whatever -- just an extrapolation of the sort of tech that TED celebrates. That civilization could program self-replicating probes to visit every planetary system in the galaxy. If they launched the first probes just after midnight one August day, then before breakfast same day, they could have colonized the galaxy. Intergalactic colonization isn't much more difficult, it just takes longer. A civilization from any one of millions of galaxies could have colonized our galaxy.
Vesolje je staro približno 13,8 milijard let. Če predstavimo starost vesolja z enim letom, je naša vrsta nastala približno 12 minut pred polnočjo 31. decembra. Zahodna civilizacija obstaja nekaj sekund. Izvenzemeljske civilizacije bi se lahko začele v poletnih mesecih. Predstavljajte si poletno civilizacijo, kako razvija tehnologijo, ki je mnogo bolj napredna od naše, a temelji na sprejeti fiziki, ne govorim o črvinah ali warp pogonu ali čemer koli že, samo ekstrapolacija neke vrste tehnologije, ki jo slavi TED. Ta civilizacija bi lahko programirala samopodvojevalne vesoljske kapsule, da bi obiskala vse planetarne sisteme v galaksiji. Če bi prve sonde lansirali malo po polnoči nekega avgustovskega dne, bi pred zajtrkom istega dne že lahko kolonizirali galaksijo. Intergalaktična kolonizacija ni veliko težja, samo dlje traja. Civilizacija iz katere koli od milijona galaksij bi lahko kolonizirala našo galaksijo.
Seems far-fetched? Maybe it is, but wouldn't aliens engage in some recognizable activity -- put worldlets around a star to capture free sunlight, collaborate on a Wikipedia Galactica, or just shout out to the universe, "We're here"?
Se zdi za lase privlečeno? Morda je, ampak ali se ne bi Nezemljani lotili kake prepoznavne aktivnosti ... okoli zvezde bi nanizali planetoide, da bi ujeli zastonj svetlobo, sodelovali pri Wikipediji Galaktiki ali preprosto zakričali v vesolje: "Tukaj smo!"?
So where is everybody? It's a puzzle because we do expect these civilizations to exist, don't we? After all, there could be a trillion planets in the galaxy -- maybe more.
Kje so torej vsi? To je uganka, ker pričakujemo, da te civilizacije obstajajo, kajne? Konec koncev je lahko v galaksiji bilijon planetov, mogoče več.
You don't need any special knowledge to consider this question, and I've explored it with lots of people over the years. And I've found they often frame their thinking in terms of the barriers that would need to be cleared if a planet is to host a communicative civilization. And they usually identify four key barriers.
Nobenega posebnega znanja ne potrebujete, da razmislite o tem vprašanju. Jaz sem ga leta in leta raziskoval z mnogimi ljudmi. Ugotovil sem, da pogosto omejujejo svoje razmišljanje s preprekami, ki bi jih bilo potrebno odstraniti, če bi naj nek planet bil dom komunikativne civilizacije. In ponavadi identificirajo štiri ključne prepreke:
Habitability -- that's the first barrier. We need a terrestrial planet in that just right "Goldilocks zone," where water flows as a liquid. They're out there. In 2016, astronomers confirmed there's a planet in the habitable zone of the closest star, Proxima Centauri -- so close that Breakthrough Starshot project plans to send probes there. We'd become a starfaring species. But not all worlds are habitable. Some will be too close to a star and they'll fry, some will be too far away and they'll freeze.
bivalnost, to je prva prepreka. Potrebujemo zemeljski planet v tisti ravno pravi idealni coni, kjer voda teče kot tekočina. Taki obstajajo. Leta 2016 so astronomi potrdili, da obstaja planet v naseljivi coni najbližje zvezde, Proxima Centauri, tako blizu, da bo projekt Breakthrough Starshot tja poslal vesoljske kapsule. Postali bi civilizacija, ki potuje med zvezdami. A vsi svetovi niso naseljivi. Nekateri bodo preblizu zvezdi in se bodo scvrli. Nekateri bodo predaleč in bodo zmrznili.
Abiogenesis -- the creation of life from nonlife -- that's the second barrier. The basic building blocks of life aren't unique to Earth: amino acids have been found in comets, complex organic molecules in interstellar dust clouds, water in exoplanetary systems. The ingredients are there, we just don't know how they combine to create life, and presumably there will be worlds on which life doesn't start.
Abiogeneza, ustvarjanje življenja iz neživljenja, je druga prepreka. Osnovni gradniki življenja niso značilni le za Zemljo. Aminokisline smo našli tudi na kometih, kompleksne organske molekule v medzvezdnih oblakih prahu, vodo v zunajosončnih sistemih. Sestavine so na voljo, a ne vemo, kako se skombinirajo, da usvarijo življenje. Domnevno obstajajo tudi svetovi, na katerih se življenje ne začne.
The development of technological civilization is a third barrier. Some say we already share our planet with alien intelligences. A 2011 study showed that elephants can cooperate to solve problems. A 2010 study showed that an octopus in captivity can recognize different humans. 2017 studies show that ravens can plan for future events -- wonderful, clever creatures -- but they can't contemplate the Breakthrough Starshot project, and if we vanished today, they wouldn't go on to implement Breakthrough Starshot -- why should they? Evolution doesn't have space travel as an end goal. There will be worlds where life doesn't give rise to advanced technology.
Razvoj tehnološke civilizacije je tretja prepreka. Nekateri pravijo, da že delimo planet z izvenzemeljsko inteligenco. Študija iz l. 2011 je pokazala, da sloni sodelujejo, da rešijo probleme. Študija iz l. 2010 je pokazala, da lahko hobotnica v ujetništvu prepozna različne ljudi. Študije iz l. 2017 so pokazale, da znajo vrane načrtovati za prihodnost - čudovita, pametna bitja - a ne morejo ustvariti projekta Breakthrough Starshot in če bi danes izginili, ne bi uporabile projekta Breakthrough Starshot - zakaj bi ga? Končni cilj evolucije ni vesoljsko potovanje. Obstajajo svetovi, kjer življenje ne ustvarja napredne tehnologije.
Communication across space -- that's a fourth barrier. Maybe advanced civilizations choose to explore inner space rather than outer space, or engineer at small distances rather than large. Or maybe they just don't want to risk an encounter with a potentially more advanced and hostile neighbor. There'll be worlds where, for whatever reason, civilizations either stay silent or don't spend long trying to communicate.
Komunikacija po vesolju, to je četrta prepreka. Morda napredne civilizacije raje raziskujejo bližnje vesolje kot pa daljnje vesolje ali pa raje konstruirajo za manjše razdalje, ne večje. Ali mogoče preprosto nočejo tvegati srečanja s potencialno naprednejšim in sovražnejšim sosedom. Obstajajo svetovi, kjer civilizacije iz katerih koli razlogov ali želijo biti tiho ali pa ne poskušajo komunicirati dolgo.
As for the height of the barriers, your guess is as good as anyone's. In my experience, when people sit down and do the math, they typically conclude there are thousands of civilizations in the galaxy. But then we're back to the puzzle: Where is everybody? By definition, UFOs -- including the one I saw -- are unidentified. We can't simply infer they're spacecraft. You can still have some fun playing with the idea aliens are here. Some say a summer civilization did colonize the galaxy and seeded Earth with life ... others, that we're living in a cosmic wilderness preserve -- a zoo. Yet others -- that we're living in a simulation. Programmers just haven't revealed the aliens yet. Most of my colleagues though argue that E.T. is out there, we just need to keep looking, and this makes sense. Space is vast. Identifying a signal is hard, and we haven't been looking that long. Without doubt, we should spend more on the search. It's about understanding our place in the universe. It's too important a question to ignore.
Kar se tiče največjih preprek, lahko ugibate tako kot jaz. Po mojih izkušnjah ljudje, ko sedejo in računajo, tipično zaključijo, da je v galaksiji na tisoče civilizacij. Pa smo spet pri uganki: kje so vsi? Definicija pravi, da so NLP-ji, vključno s tistim, ki sem ga jaz videl, neidentificirani. Ne moremo kar sklepati, da so vesoljska plovila. Še vedno se lahko malo pozabavate z idejo, da obstajajo Nezemljani. Nekateri pravijo, da je neka poletna civilizacija kolonizirala galaksijo in na Zemlji zasejala življenje. Drugi pravijo, da živimo v divjem kozmičnem rezervatu, živalskem vrtu. In tretji pravijo, da živimo v simulaciji. Programerji samo še niso razkrili Nezemljanov. Večina mojih kolegov trdi, da E.T. obstaja, samo poiskati ga moramo, in to je smiselno. Vesolje je prostrano. Identificirati signal je težko in ne iščemo še dolgo. Nedvomno bi morali za iskanje zapraviti več. Gre za razumevanje, kaj v vesolju pomenimo. To vprašanje je preveč pomembno, da bi ga ignorirali.
But there's an obvious answer: we're alone. It's just us. There could be a trillion planets in the galaxy. Is it plausible we're the only creatures capable of contemplating this question? Well, yes, because in this context, we don't know whether a trillion is a big number. In 2000, Peter Ward and Don Brownlee proposed the Rare Earth idea. Remember those four barriers that people use to estimate the number of civilizations? Ward and Brownlee said there might be more.
A obstaja očiten odgovor: sami smo. Samo mi smo. V galaksiji lahko obstaja bilijon planetov. Ali je verjetno, da smo edina bitja, sposobna razmišljati o tem vprašanju? No, da, ker v tem kontekstu ne vemo, ali je bilijon velika številka. L. 2000 sta Peter Ward in Don Brownlee prišla na plan z idejo Rare Earth. Se spomnite tistih štirih preprek, s katerimi ljudje ocenjujejo število civilizacij? Ward in Brownlee sta rekla, da jih je morda več.
Let's look at one possible barrier. It's a recent suggestion by David Waltham, a geophysicist. This is my very simplified version of Dave's much more sophisticated argument. We are able to be here now because Earth's previous inhabitants enjoyed four billion years of good weather -- ups and downs but more or less clement. But long-term climate stability is strange, if only because astronomical influences can push a planet towards freezing or frying. There's a hint our moon has helped, and that's interesting because the prevailing theory is that the moon came into being when Theia, a body the size of Mars, crashed into a newly formed Earth. The outcome of that crash could have been a quite different Earth-Moon system. We ended up with a large moon and that permitted Earth to have both a stable axial tilt and a slow rotation rate. Both factors influence climate and the suggestion is that they've helped moderate climate change. Great for us, right? But Waltham showed that if the moon were just a few miles bigger, things would be different. Earth's spin axis would now wander chaotically. There'd be episodes of rapid climate change -- not good for complex life. The moon is just the right size: big but not too big. A "Goldilocks" moon around a "Goldilocks" planet -- a barrier perhaps.
Poglejto si eno možno prepreko. Gre za nedavni predlog Davida Walthama, geofizika. To je moja zelo poenostavljena verzija Davidovega mnogo bolj sofisticiranega argumenta. Tu smo lahko, ker so Zemljini prejšnji prebivalci uživali štiri milijarde let lepega vremena - boljšega in slabšega, a bolj kot ne blagega. A dolgoročna vremenska stabilnost je čudna, če ne zaradi drugega, zato; ker lahko astronomski vplivi potisnejo planet proti zamrznitvi ali cvrenju. Namig - naša Luna je pomagala, kar je zanimivo, saj prevladujoča teorija pravi, da je Luna nastala, ko se je Theia, gmota, velika kot Mars, zaletela v novo formirano Zemljo. Izid trka bi lahko bil precej drugačen sistem Zemlja - Luna. Tako pa je nastala velika Luna, kar je omogočilo Zemlji, da ima tako stabilno nagnjenost osi kot tudi majhno hitrost rotacije. Oba faktorja vplivata na podnebje in možno je, da sta pomagala oblikovati zmerne podnebne spremembe. Super za nas, kajne? A Waltham je pokazal, da če bi bila Luna samo nekaj milj večja, bi bile stvari drugačne. Zemljina os vrtenja bi kaotično uhajala. Bili bi trenutki hitrih klimatskih sprememb, ki niso dobri za kompleksno življenje. Luna je ravno prave velikosti: velika, a ne prevelika. Idealna luna okoli idealnega planeta - morda prepreka.
You can imagine more barriers. For instance, simple cells came into being billions of years ago ... but perhaps the development of complex life needed a series of unlikely events. Once life on Earth had access to multicellularity and sophisticated genetic structures, and sex, new opportunities opened up: animals became possible. But maybe it's the fate of many planets for life to settle at the level of simple cells.
Lahko si predstavljate še več preprek. Na primer, preproste celice so se pojavile pred milijardami let, a morda je razvoj kompleksnega življenja potreboval serijo malo verjetnih dogodkov. Ko je enkrat življenje na Zemlji imelo dostop do večceličnosti, sofisticiranih genetskih struktur in spola, so se odprle nove možnosti: možne so postale živali. A mogoče je usoda mnogih planetov, da se življenje ustavi na stopnji preprostih celic.
Purely for the purposes of illustration, let me suggest four more barriers to add to the four that people said blocked the path to communicative civilization. Again, purely for the purposes of illustration, suppose there's a one-in-a-thousand chance of making it across each of the barriers. Of course there might be different ways of navigating the barriers, and some chances will be better than one in a thousand. Equally, there might be more barriers and some chances might be one in a million. Let's just see what happens in this picture.
Samo za namen ponazoritve naj predlagam še štiri prepreke kot dodatek štirim, za katere pravijo, da so preprečile pot do komunikativnih civilizacij. Spet, samo za namen ponazoritve, si predstavljajte, da obstaja možnost 1 proti 1000, da se premaga vsako od teh preprek. Seveda lahko obstajajo različni načini navigiranja med preprekami in nekatere možnosti bodo boljše kot 1 proti 1000. Prav tako lahko obstaja več preprek in nekatere možnosti bodo lahko 1 proti milijon. Pa poglejmo, kaj se zdaj zgodi.
If the galaxy contains a trillion planets, how many will host a civilization capable of contemplating like us projects such as Breakthrough Starshot? Habitability -- right sort of planet around the right sort of star -- the trillion becomes a billion. Stability -- a climate that stays benign for eons -- the billion becomes a million. Life must start -- the million becomes a thousand. Complex life forms must arise -- the thousand becomes one. Sophisticated tool use must develop -- that's one planet in a thousand galaxies. To understand the universe, they'll have to develop the techniques of science and mathematics -- that's one planet in a million galaxies. To reach the stars, they'll have to be social creatures, capable of discussing abstract concepts with each other using complex grammar -- one planet in a billion galaxies. And they have to avoid disaster -- not just self-inflicted but from the skies, too. That planet around Proxima Centauri, last year it got blasted by a flare. One planet in a trillion galaxies, just as in the visible universe.
Če galaksija vsebuje bilijon planetov, koliko jih je dom civilizaciji, ki si je sposobna kot mi izmisliti projekte, kot je Breakthrough Starshot? Bivalnost - prava vrsta planeta okoli prave vrste zvezde - in bilijon postane milijarda. Stabilnost - podnebje, ki ostane neškodljivo eone let - in milijarda postane milijon. Življenje se mora začeti - in milijon postane tisoč. Nastati mora kompleksno življenje - in tisoč postane ena. Razviti se mora uporaba sofisticiranih orodij - in imamo en planet v tisoč galaksijah. Da bi razumeli vesolje, bi morali razviti tehniki znanosti in matematike - in imamo en planet v milijon galaksijah. Da bi dosegli zvezde, bi morali biti družabna bitja, sposobna diskusije o abstraktnih konceptih z uporabo kompleksne slovnice - en planet v milijardi galaksij. In morali bi se izogniti katastrofam - ne le zadanih sebi, ampak tudi z neba. Tisti planet okoli Proxime Centauri je lani ožgal plamen. En planet v bilijonu galaksij, kot jih tudi je v vidnem vesolju.
I think we're alone. Those colleagues of mine who agree we're alone often see a barrier ahead -- bioterror, global warming, war. A universe that's silent because technology itself forms the barrier to the development of a truly advanced civilization. Depressing, right?
Mislim, da smo sami. Tisti moji kolegi, ki se strinjajo, da smo sami, pogosto pred sabo vidijo prepreko - biološki terorizem, globalno segrevanje, vojne. Vesolje, ki je tiho, ker sama tehnologija predstavlja prepreko za razvoj resnično napredne civilizacije. Depresivno, kajne?
I'm arguing the exact opposite. I grew up watching "Star Trek" and "Forbidden Planet," and I saw a UFO once, so this idea of cosmic loneliness I certainly find slightly wistful. But for me, the silence of the universe is shouting, "We're the creatures who got lucky." All barriers are behind us. We're the only species that's cleared them -- the only species capable of determining its own destiny. And if we learn to appreciate how special our planet is, how important it is to look after our home and to find others, how incredibly fortunate we all are simply to be aware of the universe, humanity might survive for a while. And all those amazing things we dreamed aliens might have done in the past, that could be our future.
Jaz trdim prav nasprotno. Odrastel sem ob Zvezdnih stezah in Prepovedanem planetu in enkrat sem videl NLP, tako da se mi ideja kozmične samote zdi malce turobna. A meni tišina vesolja kriči: "Mi smo tisti, ki se nam je posrečilo." Vse prepreke so za nami. Mi smo edina vrsta, ki jih je premagala - edina vrsta, ki je bila sposobna določiti lastno usodo. In če se naučimo ceniti, kako poseben je naš planet, kako pomembno je paziti na svoj dom in najti druge, kako izjemno srečo imamo, ker se zavedamo vesolja, bo človeštvo morda obstalo še nekaj časa. In vse te izjemne stvari, ki bi jih naj v preteklosti morda naredili Nezemljani, so lahko naša prihodnost.
Thank you very much.
Hvala lepa.
(Applause)
(aplavz)