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B The aliens are silent because they are dead

  1. Oct 5, 2016 #1

    wolram

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    https://www.sciencedaily.com/releases/2016/01/160121110932.htm

    Date:
    January 21, 2016
    Source:
    Australian National University
    Summary:
    The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens. But life on other planets would likely be brief and become extinct very quickly, say astrobiologists. In research aiming to understand how life might develop, the scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets.

    So is SETI a waste of time or is there life amidst the thousands of Earth like planets.
     
  2. jcsd
  3. Oct 5, 2016 #2
    It seems improbable to me that ours is the only planet to have evolved complex life forms. However you work the maths, the number of planets capable of supporting some form of life is staggering. Take a look at the variety of 'extremophile' life forms on Earth: https://en.wikipedia.org/wiki/Extremophile

    Once life gains a foothold it spreads. Rapid climate change may kill the majority of life but surely not all? Once a new stable point is reached the remaining organisms would thrive, mutate and spread again...

    Long live SETI!
     
  4. Oct 5, 2016 #3
    It's possible that SETI or something similar could find evidence of intelligent life.
    However we wouldn't be able to have any kind of conversation with them.
    Even if they are fairly close in cosmic scale of things it's still going to take decades, more likely centuries to get any reply to 'hi there'.
     
  5. Oct 5, 2016 #4

    Garth

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    May it be that the aliens are silent because they are sensible? - That is the ones that are sensible enough to manage to survive the technology crisis and not wipe themselves off the face of their planets.

    These would be sensible enough to have sustainable technologies, sustainable over millions or even billions of years.

    They also would therefore not waste energy by leaking it through broadcasting into space but have narrow band and narrow beam communication systems or fibre-optic type systems.

    Perhaps one day we too may become 'sensible', but so far it doesn't look too good......

    Garth
     
    Last edited: Oct 5, 2016
  6. Oct 5, 2016 #5
    Quite right, the Great Dying (aka the Permian-Triassic Extinction Event) on Earth would seem to back that up to an extent. It took around 10 million years, but the biosphere eventually bounced back from that. Theoretical life surviving in subsurface ocean worlds would also seem to be in a better position to survive when it comes to climate change as well.
    As far as SETI goes, the general idea is to listen for radio transmissions. The absence of such transmissions is taken by some as evidence there is not other intelligent life except for humans. A life form doesn't necessarily have to use technology to be intelligent. Humans got along perfectly fine on Earth for a long time without the benefit of radio, but we would still consider a human from, say, the 16th century to be an intelligent life form. It seems (from our own star system) that sub surface ocean planets might also be abundant in addition to Earth like worlds. Silence doesn't mean they're not out there, maybe they're just not listening or broadcasting. Maybe they evolved in an environment like a sub surface ocean world and aren't even concerned with what's possibly going on beyond the icy shell of their world. There are other methods apart from SETI that can be employed to search for alien life, it's possible a future breakthrough won't depend on radio transmissions at all.
     
  7. Oct 5, 2016 #6

    Chronos

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    It's just not in our nature to resist the opportunity to eavesdrop on our celestial nature. I'm confident there are people listening for messages from other planets in our own solar system. SETI may be a long shot for any number of reasons, but, what other means are available? You never know what may be out there unless you look for it. There is no reason to believe an alien civilization would not use radio even if it is a primitive and pathetically feeble technology. We don't yet have technology of the type a highly advanced civilization might use, but, I'm confident we will try as that technology is developed.
     
  8. Oct 5, 2016 #7

    CalcNerd

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    What if the planet, oh, let's say Earth, were a little more even/smooth with less tectonic activity and a LOT more water. Without land to crawl up onto, all of our life would be water borne. Probably wouldn't even have dolphins, but let's ignore that. Dolphins are highly intelligent, yet, they would NEVER develop any type of radio technology EVER! Why can I make this claim, because it is obvious, they could never develop even the simplest metallurgy. Without access to air, they could never advance any further than they currently are. Yeah, they might evolve hands of some sort and even make shift tools of a sort, but their own ocean would prevent them from developing any further. They might, might ascertain they lived on a giant ball, covered with water. but that would be the extent of it. Fire would be a foreign concept. Their experience with electricity would be from lightning strikes. They would have NO way to replicate and learn from this. They would be a civilization to be discovered, but they wouldn't be transmitting any radio signals, much less venturing out into the cosmos themselves.
     
  9. Oct 5, 2016 #8
    Several aqueous animals here have evolved methods of giving powerful electric shocks. Sharks have evolved electroreceptors to sense electromagnetic fields. Flying fish have evolved methods of staying above water for short periods of time.What's to say an intelligent subsea race would be incapable of replicating and improving upon these developments? To constrain technological advance to the narrow path that it has taken so far here is probably short sighted.
     
  10. Oct 5, 2016 #9
    The aliens are silent because they are in Happiness Boxes. Computer-generated "artificial" realities. It's the smart thing to do. All sentient races do this. In fact, what has made this clear is the human race has started to go down the same path.

    Here is a more detailed explanation. It shows why this MUST happen. It's actually a really easy thing to see, given the appearance of video games. https://omni.media/all-advanced-aliens-are-in-happiness-boxes
     
  11. Oct 6, 2016 #10
    So what would be supplying and maintaining electricity and other necessary physical infrastructure for said happiness boxes?
     
    Last edited: Oct 6, 2016
  12. Oct 6, 2016 #11

    Chronos

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    Humans tend to gravitate toward 'games' with enduring risk-reward consequences virtual games are incapable of offering.
     
  13. Oct 6, 2016 #12
  14. Oct 11, 2016 #13
    It's possible that some civilizations may have cooperated and used that cooperation to engineer their planets to control the climate and avoid extinction.
     
  15. Oct 11, 2016 #14
    I believe SETI is indeed a long shot, but like a major impact in any given century, the consequences are enormous.
     
  16. Oct 11, 2016 #15
    However you work the maths, it's still a fabrication. It is unscientific to assign a probability to an event known only ever to have occurred once.
     
  17. Oct 11, 2016 #16
    If it happened once, it will most likely, using probability, happen again, and again, and again... every very long line of anything starts with a one; I like the idea of being the first, known sentient beings, and hate the idea of being the only ones. Oh it's not thousands of planets, it's thousands of billions of planets to pick from.
    I state categorically there are numerous civilizations, thousands and thousands, and have been and will be for billions and billions of years.

    In human terms life, endlessly abundant, forever and forever. In human terms, the universe is eternal, life is eternal.
     
  18. Oct 11, 2016 #17
    No, a sample of one means it has definitely happened once.
    That offers no implication or predication at all for the likelihood (or unlikelihood) of how often it might occur elsewhere.
    We don't even have much of a clue how life got started here on Earth though there are numerous interesting ideas.
     
  19. Oct 11, 2016 #18
    On the contrary, a key aspect of science is to propose a hypothesis and establish a means of testing it against observable data. In 2013 Sarah Seager published an attempt to put some actual figures on the probability of us detecting an inhabited planet within ten years:

    https://www.cfa.harvard.edu/events/..._the_Post_Kepler_Era/Program_files/Seager.pdf

    The component FL in her equation, the fraction of planets with life, is as she says purely speculative until we find one. My point was concerning the number of planets which we would consider capable of supporting life.
     
  20. Oct 12, 2016 #19
    If they are genuinely intelligent they will avoid us, as well, they will not communicate with us... even go as far as to hide the best they can from beings like us. Seriously. We mass murder each other. Think about how that looks to people from other systems.
     
  21. Oct 12, 2016 #20
    We are genuinely intelligent. If they are too, maybe they also mass murder each other. That would certainly fit into the OP's theory!!!
     
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