FTL? - The Alcubierre Drive Initiative

Discussion in 'Alternative Technologies & Energetics' started by nivek, Sep 22, 2019.

  1. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    But it does seem to be quite clear that the number of UFO sightings skyrocketed within a couple of years after the first nuke was detonated.
    Yeah they were either nearby, or they had a monitoring station nearby - those are the most logical explanations imo.

    Your math is way off here - remember that as radius increases linearly, volume increases by the cubed power.

    There are about 14,600 stars within 100 light-years of the Earth.

    But not if the signal were transmitted FTL in some manner, either via an FTL probe or a wormhole or something we haven't imagined yet.

    No the first atomic bomb test was detonated on July 16, 1945 - almost exactly 2 years before Roswell.
     
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  2. Dejan Corovic

    Dejan Corovic Honorable

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  3. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    There are 83 star systems within 20 light-years of the Earth, containing 109 stars and 8 brown dwarfs. That's a lot to explore in the local neighborhood, once we figure out how to build field propulsion systems.
     
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  4. nivek

    nivek As Above So Below

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    We could be in the mist of a local federation of planets if even a third of those star systems supported intelligent life and like you said that's only 20 light years around, quite a small area potentially holding such wide diversity of life...

    ...
     
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  5. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    Estimating the prevalence of civilizations is really tricky business. Here’s how I look at it.

    ~10% of all stars are yellow dwarf stars like our Sun.
    ~22% of all yellow dwarf stars are orbited by an Earth-like planet in the habitable zone (HZ).

    So about 2% of all stars will be a good candidate for the emergence of life as we know it.

    We have no idea how frequently intelligent life will arise on living worlds. But since the average age of warm Earth-like worlds is 2-3 billion years older than the Earth, then if evolution tends to produce intelligent life given adequate timescales (which is a hypothesis that I favor because intelligence is the most successful adaptive advantage in nature), then perhaps half of all living worlds will yield an advanced civilization given adequate time.

    That gives us a reasonable baseline estimate: about 1% of all star systems would yield a sentient species. In that case there’s a very good chance that an intelligent species has arisen within 20 light-years of the Earth. It’s another matter to try to estimate their survival rate on cosmological timescales, so maybe it happened nearby and then they perished.

    On the other hand, if sentient species tend to survive long enough to develop gravitational field propulsion, then it’s quite likely that they colonize all over the place, shifting the numbers substantially upward – perhaps nearly all habitable worlds have been populated by interstellar civilizations. And perhaps lots of them choose to become purely interstellar, living their lives aboard starships. In this scenario the galaxies could be seething with life both on habitable worlds and moons, and strewn throughout the cosmos aboard residential exploration vessels.

    Looking at all of this with a moderately conservative mindset given the potential for life and fairly explosive expansion of civilizations, the situation does seem to favor the likelihood of abundant civilizations which would be on average vastly beyond our level of development.

    But lots of other people seem to cling to the idea that life, or at least intelligent life, is some kind of miraculously unlikely development even under ideal conditions. That might be. But such arguments seem very weak these days, because I can see no scientific reason to argue in favor of the rarity of life or even intelligent life: all of the rationalizations that people could once use to justify that perspective have collapsed in the light of modern data, imo. We now know that water is ubiquitous throughout the cosmos, so are amino acids, and we now know that warm Earth-sized worlds will have very similar compositions to the Earth - including a magnetic field, and they'll also retain similar atmospheric compositions.

    So if there's a reason that life or even intelligent life would be very rare even under very favorable conditions, I don't see it. At this point it can only be either a religious viewpoint, or one based purely on ego - the need to feel exceptional in the universe. And I find neither of those to be persuasive.
     
    Last edited: Sep 29, 2019
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  6. Dejan Corovic

    Dejan Corovic Honorable

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    "Unapologetic Rationalist" surrenders to quackery? I can not believe what I read. You should consider joining middle way, like myself, between quack & boffin camps, if you plan to go inter-stellar.

    According to that same paper from which you took that "2-3 billion years" fact, life is concentrated 2/3 of galactic radius away from the center. Earth is 1/3 of galactic radius away from the center on the very edge of the galactic high radiation zone. That means that all the oldest and coolest civilisations are at that 2/3rds and we are suburbian upstarts. They are Babylonians and we are Hebrews, the goat herders. Disapointingly, scientific facts suggest that we are the monkeys of the Milky Way. No offence to great Hebrew people, just using Biblical reference like everyone else.

    Those two facts combined explain the variety of some 50 witnessed alien speceis and relatively high frequency of observations. Without doing elaborate math, and considering that there are about 200,000 UFO reports in four main North American databases, covering period of some 70 years, it works out that there are 8 UFO observations per day somewhere in the world, but mostly in US.

    A fact that life is self-replicating software makes it incredibly tough. There are bugs eating rocks many miles bellow surface. Recent article finds that microbes festered in Western Australia 3.5 billion years ago when whole Earth hasn't yet completely cooled off. Not to mention that more than 99% of life was was wiped out on few occasions.

    So, sentient life, at 1% is not unlikely, and is maybe quite abundant across Milky Way. Unfortunately most of sentient humanoids are likely busy braking each other's skulls while working their way through a stone age of their own.

    All this makes us into utterly suburban upstarts, relative to those swell 2/3rds away (from galactic center) civilisations, that are one or two billions of years technologyicaly ahead of us.
     
    Last edited: Sep 29, 2019
  7. Spaceman spiff

    Spaceman spiff Honorable

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    Even if just 1 percent of that 1 percent made it, it would be hell of a lot more species than in all of our combined fiction. And thats just one galaxy.
     
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  8. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    Hmm...I'm going to assume that you're joking, but then make my argument for the mainstream academic credibility of these ideas anyway, because in general I find that most people think that these ideas are wildly speculative, when the opposite is true: we have every reason to believe that these concepts are physically viable because so far everything the underlying theory has predicted has been proven to be valid to the highest level of precision.

    FTL travel via metric propulsion was first elucidated by Dr. Miguel Alcubierre in 1994, and his findings have never been credibly challenged. Alcubierre received his doctorate in numerical general relativity (computing exact solutions in general relativity using Einstein's full nonlinear tensor field equations) and he’s now the Director of the Nuclear Sciences Institute at the National Autonomous University of Mexico.

    Wormhole solutions to general relativity were most thoroughly elucidated by Dr. Kip Thorne at CalTech, and he recently received a Nobel prize for his work with the first detection of gravitational waves at the LIGO facilities. Kip Thorne, John Archibald Wheeler (who co-wrote the first paper about wormholes and coined the term), and Charles Misner also together co-wrote the graduate-level academic physics textbook Gravitation, which is still widely considered to be the bible on Einstein’s general theory of relativity.

    If quantum field theory and general relativity have taught us just one very convincing lesson, it’s that their mathematical predictions are all consistently accurate to within our observational acuity every single time we test them. So the only reason we don’t have experimental proof that gravitational field propulsion performs exactly as Alcubierre described, is that we don’t have the technological capability to produce the required conditions to run the tests. Someday we will, if our species survives long enough. And evidently that "someday” arrived very long ago for many of the “somebodies” sharing the universe with us.
     
    Last edited: Sep 30, 2019
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  9. Dejan Corovic

    Dejan Corovic Honorable

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    I was more refering to FTL signal than traveling. One little tiny wormhole, 3ft wide, would rip Solar system into pieces. We don't see that happening.
     
  10. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    It would only take a wormhole slightly larger than the wavelength of the transmission frequency in order to send a signal through a wormhole, so using a high frequency could require a wormhole smaller than an atom.

    Why do you think that a wormhole 3ft wide would "rip [the] Solar system into pieces"?
     
  11. Dejan Corovic

    Dejan Corovic Honorable

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    The
    Wormholes require huge energies, particularly macroscopic ones, don't they?
     
  12. Dejan Corovic

    Dejan Corovic Honorable

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    New way to wipe out life in a whole galaxy almost at once. Some perfectly docile galaxies turn into quasars within just two months:

     
  13. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    The first studies of wormholes showed that they would require huge gravitational fields, like a black hole, and the size of the mouth is proportional to the mass-energy requirements. But that type of wormhole collapses so quickly that nothing - not even light - can pass through it.

    The work by Kip Thorne and others has explored the notion of a stable wormhole, in which case the mouths of the wormhole would have to be kept open by huge magnitudes of exotic matter and/or negative energy (though some physicists speculate that dark energy might do the trick, if it could be intensely concentrated). Hawking radiation might necessitate a high on-going energy input to keep a tiny wormhole open, but I haven't read any papers specifically about microscopic wormholes.

    In any case a stable wormhole would require roughly equal magnitudes of negative mass-energy and positive mass-energy, which suggests that the net external gravitational field would be very small and possibly nonexistent via self-cancellation. But without a quantum theory of gravity the key questions about wormholes remain essentially insoluble, and we can't even be confident that they're possible until we unite gravitation with quantum field theory.

    My point is simply that if they do turn out to be possible in the context of a grand unified theory, then more advanced civilizations would likely exploit them (or some even better idea that we haven't even dreamed up yet) for relaying data essentially instantaneously across vast distances. And if wormholes don't work out, the theoretical physics of FTL probes looks pretty convincing at this point, so they could transport data across vast distances at arbitrarily high speeds.
     
    Last edited: Oct 1, 2019
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  14. nivek

    nivek As Above So Below

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    Would wormholes of any significant size, say to fly a ship through, occur naturally and as of yet undetected?...I would hazard to guess that if it's possible for a wormhole to open naturally it would be in a region of space devoid of any stars or planets, the energy sparking such an event would rip them apart...

    ...
     
  15. Thomas R. Morrison

    Thomas R. Morrison Unapologetic Rationalist & Grand Inquisitor

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    Some physicists have speculated that a pair of black holes could connect, but that idea seemed to fall apart when that type of wormhole was found to collapse faster than light could traverse it.

    And the stable wormholes would require an extremely unnatural and symmetric distribution of positive and negative energy...if they can exist at all. So it seems radically implausible that any stable wormholes would form under natural conditions.

    But we can't be 100% sure of much, regarding wormholes, until we have a cohesive theory that can describe both their spacetime characteristics and their quantum dynamics. The fact that we haven't seen anything in nature which might resemble the formation of a wormhole seems like a pretty strong indication that they don't form naturally - at least on this side of the surface of last scattering anyway, because the universe is so vast that even very exotic events happen quite frequently and nowadays we pick them up with various instruments.
     
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  16. nivek

    nivek As Above So Below

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    I was thinking the sudden collapse of a star or two black holes merging would cause such a tremendous amount of energy that its possible for a wormhole to open but with an exit aperture occurring in a random location, like a one way opening because on the exit side there would be no energy to keep it open, what would keep it open would be the main event that started the process...As long as there's energy to keep it open it would remain open forcing energy through the vortex and out the exit side until that energy dissipated causing it to close...The level of energy created by the main event would determine the distance of the exit aperture from the original opening, or have I watched too much Star Trek lol...

    ...
     
  17. Spaceman spiff

    Spaceman spiff Honorable

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  18. nivek

    nivek As Above So Below

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    I think for species that reside closer to us would be the culprits if we were to discover we are being watched by some alien technology, we would be a greater potential threat to them than a species on the other side of the galaxy, if they happen to cross our path...Isn't this a prevailing theory in one of the moon conspiracies, of aliens having bases there, possibly monitoring our activities?...

    ...
     

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