Brian Cox - Alien Life & The Great Filter Hypothesis — Transcript

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1. 0:01I don't understand what what is your purpose here
2. 0:09if civilizations are common then there should be  civilizations ahead of us because there's been
3. 0:14so much time you imagine the time scales we've  been around take 40 000 years I don't know how
4. 0:19long our civilization's been around let's say that  the Galaxy is pretty much as old as the universe
5. 0:24it's 13 billion years worth of time so the idea  that there are no civilizations Eros you know
6. 0:31100 million years ago 200 million years ago one  billion years ago and imagine what they'd be like
7. 0:37if they'd survived I mean we've been we've had  science for let's say since Newton or Copernicus
8. 0:43500 years at most and look what we've done we've  gone beyond the solar system with voyager we've
9. 0:49walked on the moon we're about to go to Mars I  would think so we're about to begin colonizing
10. 0:54our own solar system so we've done that in  500 years imagine a million years it's one
11. 1:00of the arguments often used to say there aren't  any civilizations out there in the galaxy it's
12. 1:05called the Fermi Paradox because if you imagine  a civilization that's a millionaire ahead of us
13. 1:09they should have written their presence across  the sky by now we used to see him I mean you'll
14. 1:14see us if we survive in million years into the  future actually even a few thousand years into
15. 1:21the future we will be exploring the Galaxy we  will have spacecraft that are going toward the
16. 1:26Stars we will be doing it so our signature will  become visible I'm sure if we last is Earth a
17. 1:34lone Oasis Of Life or is the universe teeming  with hidden organisms waiting to be discovered
18. 1:39the vast number of stars each  potentially harboring planets
19. 1:43with conditions ripe for Life leads many  scientists to believe we can't be alone
20. 1:48the very elements that sparked life on Earth  carbon hydrogen oxygen are abundant throughout the
21. 1:55cosmos could this be the cosmic recipe for Life a  universal secret shared across the galactic canvas
22. 2:01join us as we embark on an unparalleled journey  to unlock the mystery of life beyond our world
23. 2:07if you look at the history of life on Earth then  so Earth formed there was no life it was a ball
24. 2:12of rock and almost as soon as it cooled down we  see evidence of life so certainly 3.8 billion
25. 2:19years ago possibly even further back than that we  see evidence of life on Earth so somewhere along
26. 2:26the line geochemistry active geochemistry became  biochemistry on Earth and we have some idea if
27. 2:35you get a gradients of temperature and acid and  alkaline and the conditions that are naturally
28. 2:40present on the surface of oceans then complex  carbon chemistry spontaneously happens so we know
29. 2:49that life almost certainly we know that life began  on Earth the other option is it came from space or
30. 2:54something like that but it probably didn't it  probably began on Earth so that means that at
31. 2:58least here that happened and that we know that  the conditions that led to the origin of life on
32. 3:04Earth were present on Mars 3.8 4 billion years ago  and we know that they're present on Europa today
33. 3:11so I don't see that there's anything special  life is just chemistry the idea that geochemistry
34. 3:18becomes biochemistry is not fanciful because  it happened here so I think that given the same
35. 3:24conditions it would be surprising to me if the  same thing didn't happen in that life begins to
36. 3:31test that is one of the great frontiers of science  now it's one of the great challenges so it would
37. 3:37be good to know what I've said is right the way we  find out is to find life or evidence of past life
38. 3:43the universe may be filled with life so  why haven't we found any evidence yet this
39. 3:48perplexing question is known as the Fermi Paradox  some propose the zoo hypothesis suggesting that
40. 3:54extraterrestrial civilizations might be watching  us intentionally avoiding contact like zookeepers
41. 3:59observing animals meanwhile the recent surge in  UFO and UAP reports has stirred excitement and
42. 4:06curiosity but are these truly indications of other  worldly visitors despite tantalizing stories and
43. 4:12sightings solid proof remains elusive the Galaxy  remains a silent enigmatic void withholding its
44. 4:19secrets but who knows really could the answers  be just beyond our reach waiting for the right
45. 4:24moment to reveal themselves that point seems  to me once you said I don't know you might as
46. 4:30well put full stop there and shut up I don't know  but then I think this you know it's like someone
47. 4:35asked me the other day about unidentified flying  objects as this Congressional panel on UFOs and
48. 4:40I said the thing is it's in the words and it's  just unidentified so should we just show up now
49. 4:45it's still identified therefore I think there's an  alien civilization close by that's building flying
50. 4:50sources that are trying to evade our defenses  and there's a big cover-up and the CIA are not
51. 4:54telling us everything so no unidentified that's  it I don't know what they are the Fermi Paradox
52. 5:00continues to baffle us a cosmic conundrum  echoing through the void if the universe is
53. 5:06teeming with life why is the evidence so elusive  some argue that technological limitations hinder
54. 5:12our search confining our gaze to a mere sliver  of the galactic expanse others believe that the
55. 5:18great filter an unknown barrier to the advancement  of civilizations might be preventing species from
56. 5:24reaching a point where we could detect them could  it be that life is abundant but intelligent life
57. 5:30is exceptionally rare or is there something  more profound a hidden truth veiled by the
58. 5:35vastness of space itself awaiting our discovery  there is an argument as well that technology is
59. 5:41so Advanced would be difficult for us to detect I  mean we tend to think of Starship Star Wars right
60. 5:47big energy things that you can see the signature  of but actually it may be the civilization just
61. 5:51becomes a nano civilization because that's more  efficient it's a better way to do things so it's
62. 5:57possible I suppose that there are space probes  all over the place that are so small and is so
63. 6:02efficient and you sell little energy that we  just don't see them as far as that is possible
64. 6:08the great filter hypothesis presents a  chilling explanation for our Cosmic silence
65. 6:13it suggests that somewhere along the path to  becoming a space-faring civilization there's
66. 6:19a nearly insurmountable barrier a filter that  prevents advancement is this filter behind
67. 6:25us making our existence a rare Triumph against  astronomical odds or is it ahead of us a future
68. 6:32obstacle that might extinguish our civilization  as it has possibly done to others before
69. 6:37the great filter looms large in our search for  extraterrestrial intelligence casting a shadow
70. 6:43of both hope and Dread it's a theory that forces  us to confront not only our place in the universe
71. 6:49but our future within it there's in the Drake  equation which is wasn't trying to estimate
72. 6:54the number of civilizations really it was to try  and focus your mind on what the variables are how
73. 6:58you should think about it but at the end of that  the way that you wrote it there's an L the letter
74. 7:03L which is the length of time a civilization  will be broadcasting or contactable through
75. 7:08radio waves and I mean we've been around in that  form which is with radio telescope I like it that
76. 7:15astronomers Define civilization as when did you  get a radio telescope then you're civilized and
77. 7:20you know it's less than 100 years so we've only  been that L for us is the contextable lifetime of
78. 7:26civilization it is you know 100 years or so for  us you know we could have gone you think about
79. 7:31the Cuban Missile Crisis for example that could  have been 20 years for us you know we're still in
80. 7:36that position you know how long is L how long  is the lifetime of civilization wants it once
81. 7:42it acquires nuclear weapons for example which  he will how long does your civilization manage
82. 7:47that it's not clear we're doing the experiment  and we've dodged it a few times when might the
83. 7:54great filter arise some propose it occurs in the  early stages of life where the spark of existence
84. 8:00is snuffed out by harsh Cosmic realities others  argue it may surface later when intelligence
85. 8:06emerges presenting challenges that civilizations  struggle to overcome the development of complex
86. 8:12technology though a sign of advancement could  also Mark a dangerous precipice take nuclear
87. 8:18weapons for example a Marvel of human Innovation  yet a potential harbinger of our own destruction
88. 8:23could they represent a great filter a threshold  that has annihilated other civilizations before us
89. 8:30the answers May Define not only our quest to  find extraterrestrial life but our very survival
90. 8:35Oppenheimer thought about this a lot because  he now the Manhattan Project he'd been Felts
91. 8:41himself responsible for creating the bomb you  can look at it many ways you can say that he's
92. 8:46shortened the war in the Pacific I can say that  he invented this thing that we don't have the
93. 8:50wisdom to control he was very worried about what  he'd done he just strongly felt that he might
94. 8:55still be right that we didn't have the wisdom to  control the knowledge so it could be the case so
95. 9:00that could be another answer so the great silence  that people call the Learning Paradox might just
96. 9:04be because we are fundamentally idiots the great  stupidity intelligent beings are fundamentally
97. 9:11just dumb they raise themselves from the Universe  I challenge anyone who's listening to argue that
98. 9:17there's at least a possibility that that's  what we are the great filter hypothesis delves
99. 9:22deeper into the haunting Silence of the cosmos  offering a profound explanation for our isolation
100. 9:28could it be that every civilization faces a  series of critical barriers tests that must
101. 9:33be overcome to reach the Stars these barriers  might include surviving planetary catastrophes
102. 9:39avoiding self-annihilation through Warfare or  navigating The Perils of unchecked technological
103. 9:44advancement the great filter posits that few  if any Traverse this perilous path successfully
104. 9:51hence the quiet universe it's a theory that  resonates with both optimism and warning
105. 9:57urging us to reflect on our choices  on the universal Journey we share
106. 10:01the way I look at life is that it's the  most important phenomenon that exists
107. 10:06in the universe without life the universe is by  definition meaningless clearly meaning enters the
108. 10:13universe with Consciousness and Consciousness  is a property of living things and so without
109. 10:19living things there's no meaning so I think that  if this is the only planet in the Milky Way galaxy
110. 10:24that currently hosts an intelligent civilization  then it's the only island of meaning in a CF 400
111. 10:30billion stars and therefore we have a tremendous  responsibility to protect this island of meaning
112. 10:37if we mess it up we will be responsible if that's  the case for annihilating meaning perhaps forever
113. 10:45in a galaxy so I think life's important in our  quest to understand the universe we've explored
114. 10:51the tantalizing possibilities of life elsewhere  grappled with the Enigma of the Fermi Paradox
115. 10:57and delved into the profound great filter  hypothesis from the basic elements forming
116. 11:02life to the silence echoing across the cosmos our  journey reveals both hope and caution but as we
117. 11:08gaze into the infinite void one question ignites  our curiosity and fuels our imagination in this
118. 11:15vast Mysterious Universe are we the exception or  the rule is the key to unlocking alien life within
119. 11:21our grasp or is the secret buried deeper in the  cosmos than we ever dared to dream foreign [Music]