This (which can be written in many similar ways) ... Firs

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A curmudgeonly view of SETI
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Drake (Green Bank) equation
NN fp fe fl fi fc (L/Lmax)
This (which can be written in many similar ways)
at least organizes our ignorance. But is it
leading us to concentrate on the right questions?
In other words, who needs it? In any case, we can
look at the terms
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N number of stars in the Galaxy
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N number of stars in the Galaxy
400 billion (the McDonalds number)
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fp fraction of stars with planets
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fp fraction of stars with planets
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fe fraction of Earthlike planets
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How earthlike is earthlike?

• We can see how to do global assays nearby
• Environment where life appeared???
• Solar System environments may help
• Rare Earth or not?
• Mass, large moon, temperature range, tides,
  rotation period, lifetime, liquid water,
  atmosphere, location of Jovian neighbors which
  matter???

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fl fraction of life-bearing planets
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fi fraction of living worlds with intelligence

• Fossil record complexity, rather than appearance
  of first life forms, is the time bottleneck

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fi fraction of intelligences which develop
communicative civilizations

• SETI involves either interstellar communication
  or starflight,defining the sample
• First per planet may always win
• Contingency (Africa versus South America)

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L lifetime in communicative state
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Beware of psychological mirroring

• Conventional widom at various times has thought
  of L ended by nuclear war, ecological collapse,
  Chinese coup, era of navel-gazing
• Communication imperatives?
• Primogeniture and European expansion drivers for
  exploration accidental

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Natural (dis)advantages
Jared Diamond, in Guns, Germs, and Steel, make a
strong argument that geography and ecology picked
the winners in human development long ago. What
unseen advantages might we, or might hypothetical
intelligences, have or lack?
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What good is intelligence?
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Deliberate/accidental detection
Our own leakage decreases is accidental
detection itself an accident of development?
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How to cheat Frank Drake

• Interstellar expansion (and there are Earthly
  lessons Vinland versus Florida)
• Multiple (dis)appearances of intelligence (a la
  Karl Schroders Permanence)
• Ignorance of Earthlike context
• Scouring of worlds by cosmic events

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New(ish) Approaches

• Gravitational lensing
• Lasers
• Interstellar scintillation as a free amplifier
• Chasing beamed phenomena
• Local ambassadors

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Star-star microlensing
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Gamma-ray bursts as beacons
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Gamma-ray bursts as beacons