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LIFE - 1/27/2010 - Are We Alone?
 

LIFE - 1/27/2010 - Are We Alone?

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Lecture presentation from Daniel Kainer, Biology Professor, Lone Star College-Montgomery

Lecture presentation from Daniel Kainer, Biology Professor, Lone Star College-Montgomery

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    LIFE - 1/27/2010 - Are We Alone? LIFE - 1/27/2010 - Are We Alone? Presentation Transcript

    • Fermi’s Paradox – Where is Everybody?
    • 50 Solutions to a Paradox
    • Who was Enrico Fermi (1901-1954)?
      • Discovered the “weak” force
      • 1 of only 4 forces in nature
      • Designed the world’s 1st nuclear reactor
      • Last great theoretical AND experimental physicist
      • Part of a team that identified the nuclear chain reaction underlying nuclear weapons
      • Won the Nobel Prize for physics in 1938
    • Fermi Questions
      • Relied on estimates and were deeply insightful
      • How many grains of sand are on the earth’s beaches?
      • How far can a crow fly?
      • How many molecules of air from Caesar’s last breath do you take in with each lungful of air?
      • How many piano tuners are there in Chicago?
      • Where is everybody?
    • The Fermi Paradox
      • “Where is everybody?”
      • With even ordinary rocket technology, a species could colonize the entire galaxy in ten million years. Why don’t we see them?
      • Fermi’s answer: they aren’t there.
    • The Drake Equation
    • 3 Possible Resolutions
    • 3 Possible Resolutions
      • They are here
    • 3 Possible Resolutions
      • They are here
      • They exist but have not yet communicated
    • 3 Possible Resolutions
      • They are here
      • They exist but have not yet communicated
      • They do not exist
    • They are here…
    • They are here: Solution #1
      They are here and they call themselves Hungarians…
    • They are here: Solution #1
      They are here and they call themselves Hungarians…
      Johnvon
      Neumann
      Edward Teller
    • They are here: Solution #2
      They are here and are meddling in human affairs…
    • They are here: Solution #2
      They are here and are meddling in human affairs…
      Most UFOs become IFOs – must they all be in order to “disprove” alien invasions?
    • They are here: Solution #3
      They were here and left evidence of their presence…
    • They are here: Solution #3
      They were here and left evidence of their presence…
      2001
      1976
    • They are here: Solution #3
                                           
      They were here and left evidence of their presence…
      Erich von Daniken
      Tunguska, 1908
    • They are here: Solution #3
                                           
      They were here and left evidence of their presence…
      NASA has already “parked” sattelites at some of these Lagrangian points L1 and L2. What about ET?
      Lagrangian Points
    • They are here: Solution #4
      They exist and they are us – We are all aliens!
    • They are here: Solution #4
      They exist and they are us – We are all aliens!
    • They are here: Solution #5
      The Zoo Scenario…
    • They are here: Solution #5
      The Zoo Scenario…
    • They are here: Solution #6
      The Interdict Scenario…
    • They are here: Solution #6
      The Interdict Scenario…
    • They are here: Solution #7
      The Planetarium Hypothesis…
    • They are here: Solution #7
      The Planetarium Hypothesis…
    • They exist but have not yet communicated
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
      Cosmic horizon = 10-12 billion light years
      Sloan Digital Sky Survey
    • They exist but have not communicated: Solution #8
                                                                                                                                                                                                                                                                                                          
      The Stars are Far Away…
      • Only explains why they haven’t visited us (maybe)
      0.000058c
      73,000 years to a Centauri
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
      • Only explains why they haven’t visited us (maybe)
      4.2 light years away
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
      • Rockets carry fuel and payload
      • Ramjets carry only payload
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
    • They exist but have not communicated: Solution #8
      The Stars are Far Away…
      Exotic technologies:
    • They exist but have not communicated: Solution #9
      They have not had time to reach us…
    • They exist but have not communicated: Solution #9
      They have not had time to reach us…
      • Population growth: 0.03/year; emmigration rate =0.0003/year
      • Colonization in ~60 million years
      • Diffusion process – colonization time would depend on population growth
      • Near zero: 13 billion years for galactic colonization
      • Does not account for speed of interstellar travel
      • Other motives for exploration/colonization?
    • They exist but have not communicated: Solution #10
      A Percolation Theory Approach…
    • They exist but have not communicated: Solution #10
      A Percolation Theory Approach…
      Assumptions:
      • Interstellar travel is possible but difficult
      • Parent civilization exerts only weak control over its colonies
      • Civilizations can’t establish colonies on already colonized worlds
      • A given colony will have a certain probability of having a “colonization drive”
      Collectively, these assumptions produce apercolation problem
    • They exist but have not communicated: Solution #10
      A Percolation Theory Approach…
      Percolation problem: Mathematical method of filling a large array of empty
      Spaces with objects
      • Key task is to Calculate the probability that, in a given system, there is a continuous path from one end of the system to another
      • forest fires, disease, etc.
      • N cells, each w/probability p of being
      populated – size of p determines
      population density
      • Spanning cluster when p>pc
    • They exist but have not communicated: Solution #10
      A Percolation Theory Approach…
      Fermi paradox might be resolved:
      • p
      has reached us
      • p=pc: earth is in a great void
      • p>pc: earth is in a small void
      • Advantage: No motives are assumed
      • Disadvantage: Does not explain the “Great Silence”
    • They exist but have not communicated: Solution #11
      Bracewell-von Neumann Probes…
    • They exist but have not communicated: Solution #11
      Bracewell-von Neumann Probes…
      Are automatons: can function in the world & make copies of themselves
      • consists of a constructor & a program
      • We are automatons
      Ronald Bracewell
      John von Neumann
    • They exist but have not communicated: Solution #11
      Bracewell-von Neumann Probes…
      • Galactic colonization time would be short
      • Fermi might ask: “Where are the probes?”
      • Copying errors would lead to mutations; mutations to evolution
      • Different sources = different “species”
      • Would all ETCs choose not to risk it?
    • They exist but have not communicated: Solution #12
      We are Solar Chauvinists…
    • They exist but have not communicated: Solution #12
      We are Solar Chauvinists…
      G2
      O?
      Dyson Spheres
    • They exist but have not communicated: Solution #13
      They Stay at Home…
    • They exist but have not communicated: Solution #13
      They Stay at Home…
      Will we ever go back?
      Are there good reasons to “go for a cosmic swim?”
      • How likely is it that all ETCs
      have chosen to “stay home”?
      Dennis Tito
    • They exist but have not communicated: Solution #14
      …and Surf the Net
    • They exist but have not communicated: Solution #14
      …and Surf the Net
      • Plausible for individual species (us?), but not likely for all civilizations
    • They exist but have not communicated: Solution #15
      They are signaling but we don’t know how to listen…
    • They exist but have not communicated: Solution #15
      They are signaling but we don’t know how to listen…
      SETI: radio, visible Dyson Spheres: infrared
    • They exist but have not communicated: Solution #15
      They are signaling but we don’t know how to listen…
      Tachyons:
      There was a young lady named Bright,
      Whose speed was far faster than light.
      She went out one day,
      In a relative way,
      And returned the previous night!
      -Reginald Buller
    • They exist but have not communicated: Solution #16
      They are signaling but we do not know at which frequency to listen…
    • They exist but have not communicated: Solution #16
      They are signaling but we do not know at which frequency to listen…
      Even with
      billions of
      channels, there
      is still nothing
      on!
      H: 1.42 GHz
      OH: 1.64 GHz
      Other logicalspots?
    • They exist but have not communicated: Solution #17
      Our search strategy is wrong…
    • They exist but have not communicated: Solution #17
      Our search strategy is wrong…
      • All-sky surveys
      • Targeted searches
      • Optical SETI
      • SETI @ Home
    • They exist but have not communicated: Solution #18
      The signal is already there in the data…
    • They exist but have not communicated: Solution #18
      The signal is already there in the data…
      • Could some astronomical phenomena be ETC signatures?
      • Gamma ray bursters: Cataclysmic fireball or ET chatter?
      • Infrared excess: Dust or Dyson Sphere?
    • They exist but have not communicated: Solution #19
      We have not listened long enough…
    • They exist but have not communicated: Solution #19
      We have not listened long enough…
      SETI:Billions of stars, billions of frequencies, and billions ofyears: trillions of possible combinations!
    • They exist but have not communicated: Solution #20
      Everyone is listening; No one is transmitting…
    • They exist but have not communicated: Solution #20
      Everyone is listening; No one is transmitting…
    • They exist but have not communicated: Solution #20
      Everyone is listening; No one is transmitting…
      • Signal that could be detected @ 100 light years by a small antenna would require more power than entire electricity-generating capacity of the entire world
      • Same signal to be detected by an Arecibo-type dish on opposite side of Milky Way could be sent by the Arecibo telescope – but with an extremely narrow band
      • Lasers? Brief pulses can be billions of times brighter than a star.
      • Where would we point the dish or laser?
      • Isotropic transmission increases both odds and expense
    • They exist but have not communicated: Solution #21
      Berserkers…
    • They exist but have not communicated: Solution #21
      Berserkers…
      The ultimate deterrent?
    • They exist but have not communicated: Solution #21
      Berserkers…
      • Why would a culture build them?
      • Could von Neumann probes have mutated?
      • Why are we still here?
    • They exist but have not communicated: Solution #22
      They have no desire to communicate…
    • They exist but have not communicated: Solution #22
      They have no desire to communicate…
      • Fear?
      • Berserkers? Conquest?
      • Lack of curiosity?
      • “Surfing the Net” is better
      • Uninterested in “backwards” civilizations like ours?
      • Maybe in scientific matters, but what about others?
      • Nonexpansionist philosophies
      • Like China under the Ming Dynasty?
      • Noninterference policies?
    • They exist but have not communicated: Solution #23
      They develop a different mathematics…
    • They exist but have not communicated: Solution #23
      They develop a different mathematics…
      • Why does mathematics demonstrate an “unreasonable effectiveness?”
      • Platonic ideal or human construct?
      • Can evolution dictate mathematics?
      • Inferior parietal cortex
      • Discrete vs. continuous variables
      • Could other mathematics (if they exist) lead to the development of technology?
      • Inverse square law, etc.
    • They exist but have not communicated: Solution #24
      They are calling but we do not recognize the signal…
    • They exist but have not communicated: Solution #24
      They are calling but we do not recognize the signal…
      • Maybe frequencies that are obvious to us are irrelevant to them
      • Waterhole; 2 X hydrogen; pi X hydrogen, etc.
      • Some signals would be easily discerned as artificial, others not
      • Even if we detected a signal, could we interpret it?
      • And you thought the Voynich Manuscript was tough?
    • They exist but have not communicated: Solution #25
      They are somewhere, but the universe is stranger than we imagine…
    • They exist but have not communicated: Solution #25
      They are somewhere, but the universe is stranger than we imagine…
      • Parallel universes?
      • Many Worlds Interpretation of quantum mechanics
      • The Galactic Overmind?
      • Telepathy and the Space-Time-Mind Continuum?
    • They exist but have not communicated: Solution #26
      A choice of catastrophes…
    • They exist but have not communicated: Solution #26
      A choice of catastrophes…
      Gray Goo problem?
    • They exist but have not communicated: Solution #27
      They hit the singularity…
    • They exist but have not communicated: Solution #27
      They hit the singularity…
      • Moore’s Law
      • Will superhuman AI be here by 2030?
      • Will Moore’s Law steadily decrease then in an “intelligence explosion?”
      • What need would our machines then have of us?
      • The Singularity will have been reached
    • They exist but have not communicated: Solution #28
      Cloudy skies are common…
    • They exist but have not communicated: Solution #28
      Cloudy skies are common…
      Venus
      Titan
      Europa
    • They exist but have not communicated: Solution #29
      Infinitely many ETCs exist, but only one within our particle horizon (us!)…
    • They exist but have not communicated: Solution #29
      Infinitely many ETCs exist, but only one within our particle horizon (us!)…
    • They do not exist
    • They don’t exist: Solution #30
      The universe is here for us…
    • They don’t exist: Solution #30
      The universe is here for us.
    • They don’t exist: Solution #31
      Life can have emerged only recently…
    • They don’t exist: Solution #31
                                                                                                          
      Life can have emerged only recently.
    • They don’t exist: Solution #32
      Planetary systems are rare…
    • They don’t exist: Solution #32
      Planetary systems are rare.
      Protoplanetary disk
    • They don’t exist: Solution #32
      Planetary systems are rare.
    • They don’t exist: Solution #33
      We are the first…
    • They don’t exist: Solution #33
      We are the first…
    • They don’t exist: Solution #34
      Rocky planets are rare…
    • They don’t exist: Solution #34
      Rocky planets are rare…
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      • One assumption of most astrobiologists is that habitable planets must maintain stable climates over very long time periods, probably such that the planet can maintain a large supply of
      liquid water
      • Originally, the only variable that was considered was the nature of the orbit of the planet around its star
      HZ
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      • CHZ: Continuously Habitable Zone
      • Inner edge thought to be ~0.85-0.95 AU
      • Outer edge thought to be ~1.37-1.67 AU
      • Presence of Jupiter- like planets nearby
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      • Alternative (non-star) sources of energy that can support life
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      • Just how hearty is this thing we call life anyway?
      • Before you answer – check out these extremophiles!
      halophile
      Thermophiles in volcanic mudpot
      acidophile
      Deinococcus radiodurans can survive radiation levelsthousands of times higher than what would kill most
      organisms (including people) – panspermia candidate?
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      Type of Star:
      O, B, A, F, G, K, M
    • They don’t exist: Solution #35
      Continuously habitable zones are narrow…
      Galactic Habitable ZoneGalaxy Type
      irregular
      Intragalactic position:
      elliptical
      spiral
    • They don’t exist: Solution #36
      Jupiters are rare…
    • They don’t exist: Solution #36
      Jupiters are rare…
    • They don’t exist: Solution #36
      Jupiters are rare…
      Comet Shoemaker-Levy Collision with Jupiter (1994)
    • They don’t exist: Solution #37
      Earth has an optimal “pump of evolution”…
    • They don’t exist: Solution #37
      Earth has an optimal “pump of evolution”…
    • They don’t exist: Solution #38
      The galaxy is a dangerous place…
    • They don’t exist: Solution #38
                                                                                                                      
      The galaxy is a dangerous place…
      ?
      Supernova 1994I
    • They don’t exist: Solution #38
                                                                                                                      
      The galaxy is a dangerous place…
      Gamma ray burster
    • They don’t exist: Solution #39
      A planetary system is a dangerous place…
    • They don’t exist: Solution #39
      A planetary system is a dangerous place…
    • They don’t exist: Solution #39
      A planetary system is a dangerous place…
    • They don’t exist: Solution #39
      A planetary system is a dangerous place…
    • They don’t exist: Solution #40
      Earth’s system of plate tectonics is unique…
    • They don’t exist: Solution #40
      Earth’s system of plate tectonics is unique…
    • They don’t exist: Solution #41
      The Moon is unique…
    • They don’t exist: Solution #41
      The Moon is unique…
      Mars
      Uranus
      Saturn
      Jupiter
      Venus
      Earth
    • They don’t exist: Solution #42
      Life’e genesis is rare…
    • They don’t exist: Solution #42
      Life’e genesis is rare…
    • They don’t exist: Solution #43
      The prokaryote-eukaryote transition is rare…
    • They don’t exist: Solution #43
      The prokaryote-eukaryote transition is rare…
    • They don’t exist: Solution #44
      Toolmaking species are rare…
    • They don’t exist: Solution #44
      Toolmaking species are rare…
    • They don’t exist: Solution #45
      Technological progress is not inevitable…
    • They don’t exist: Solution #45
      Technological progress is not inevitable…
    • They don’t exist: Solution #46
      Intelligence at the human level is rare…
    • They don’t exist: Solution #46
      Intelligence at the human level is rare…
    • They don’t exist: Solution #47
      Language is unique to humans…
    • They don’t exist: Solution #48
      Science is not inevitable…
    • They don’t exist: Solution #49
      We Are Alone
    • Is there anyone else out there asking the eternal question: “Are We Alone?”
    • © Daniel Kainer
      Lone Star College-Montgomery