6 ms·

I'm usually a skeptic but I don't buy into the idea that we can't reason anything about aliens until we find them. Some things are just physics. Physics places

by cletus 5y ago

I'm usually a skeptic but I don't buy into the idea that we can't reason anything about aliens until we find them. Some things are just physics. Physics places absolute limits on how small or large an organism can be, for example. It's why I'm not worried about the possibility of superintelligent viruses. There is a long theory of the value of thought experiments in science. The word "atom" is derived from the Greek "atomos", which was the result of a 2000+ year old thought experiment about if something was infinitely divisible or not. Experimental evidence didn't come until the 1800s (IIRC). It seems weird that any article talking about possible alien life doesn't at least touch on the anthropic principle, which is a whole set of thought experiments. My personal view is that our knowledge of the Universe at this point isn't perfect but it's closer to correct than not. That means (IMHO) the speed of light is an absolute limit and thermodynamics holds true. With just those two things, you have a lot of constraints and you can start making some observations. For example: a burgeoning civilization needs energy (and matter), will produce waste heat and that waste heat has to go somewhere. This of course touches on various thought experiments relating to the Fermi Paradox. My personal view is that there simply aren't any starfaring civilizations to find within a pretty large (1M+ light years) light cone. And if you look at the Milky Way, if there aren't any to find now, it's highly unlikely there other civilizations beyond our light cone just because of the low probability of two (or more) such civilizations evolving to that point within 100,000 years of each other.

colordrops 5y ago
> superintelligent viruses What if some virus evolved to work super intelligently as a hive mind? > My personal view is that our knowledge of the Universe at this point isn't perfect but it's closer to correct than not. I think most of the evidence contradicts this. My suspicion is that if we continue to progress at the same rate or accelerate, in 1000 years we (assuming we are still recognizably human) will look back at our understanding of reality right now as nearly completely wrong. So your constraints don't seem to be givens. > My personal view is that there simply aren't any starfaring civilizations to find within a pretty large (1M+ light years) light cone. This makes a lot of assumptions, including that intelligent species don't accelerate quickly into something unrecognizable as they evolve to more advancement, or that our model of spacetime is basically right and there isn't much more to expand into besides our sparse region of reality.
- kiba 5y ago
  I think most of the evidence contradicts this. My suspicion is that if we continue to progress at the same rate or accelerate, in 1000 years we (assuming we are still recognizably human) will look back at our understanding of reality right now as nearly completely wrong. Most of the evidence? We haven't found any new physics phenomenon from which we can derive new technology. There's no known or theoretical ways for us to traverse to different realities let alone prove or disprove such existence, for example. This makes a lot of assumptions, including that intelligent species don't accelerate quickly into something unrecognizable as they evolve to more advancement, or that our model of spacetime is basically right and there isn't much more to expand into besides our sparse region of reality. Just because we can imagine something doesn't make it possible.
  - colordrops 5y ago
    I'm referring to historical evidence. At any point in history other than recent, our understanding of reality has been completely revised since then. And the extrapolation is that the same trend will continue. We've got zero evidence whatsover that we've found core models that can't be overridden by further discovery, and eventually made obsolete in whole by large paradigm shifts.
    - Normal_gaussian 5y ago
      I will happily argue there is pretty strong historical evidence our models are correct. In my amateur trip through philosophy from Plato to Wittgenstein I've seen a lot of acknowledgements by the intelligencia of a generation as to what is presumed, convenient, or constructed fact and what is actual fact. Paradigm shifts in thinking have gotten repeatedly smaller over the written record, and would hardly be considered a paradigm shift by previous generations.
    - Delk 5y ago
      That would be true if the development of our understanding had happened at a linear pace. It hasn't, though. Our understanding of the physical universe has grown so much within the last hundred or couple hundred years that I'm not sure understanding had grown equally much even throughout the entire preceding human history. At least you'd have to go pretty far in history. With accelerating growth of understanding you will, at some point, get to "mostly correct". I don't know if we're there yet but you can't extrapolate linearly from history that we aren't.
achenatx 5y ago
Natural selection means that they likely are warlike and violent. Warlike and violent intelligent species destroy themselves quickly so are unlikely to exist at the same time as us. Only the ones that can reengineer themselves to not be warlike and violent before they destroy themselves will survive for long enough to exist at the same time as us. Therefore it is likely any intelligent species we meet will be peaceful (among themselves at least).
mpoteat 5y ago
My view is that we can reason about organisms living in space because we are one of them. We have a sample size of one, but assuming that properties of different space-faring organisms are distributed normally, it stands to reason that the first sample collected is near to the mean of the underlying distribution. In other words, imagine a normal distribution with very, very low variance (say, 0.0001). The mean is unknown to you. If you take one sample, your sample will very likely be close to the mean.
- AnimalMuppet 5y ago
  Within your argument, what's the justification for assuming low variance?
  - mpoteat 5y ago
    There is none! Variance could be arbitrarily high I suppose. In the limit, if you assume a uniform distribution, I don't think that a single sample will give you any information about the underlying distribution characteristics. However, for the sake of the argument, variance can be arbitrarily high and still provide increasingly lower amounts of Bayesian evidence. As long as the variance is not unbounded (i.e. as long as the distribution is Gaussian, which I think is a reasonable assumption in nature), you can extract _some_ evidence from a single sample.
Enginerrrd 5y ago
Honestly, the idea of a coherent starfaring civilization is itself kind of dubious to me based on the following things: IMO, biological corporeal from for intelligence is not a longterm solution. Bodies are good at what the things they evolved to do and interstellar travel aint one of those things. Now downloading your consciousness onto a robot/computer/swam on the other hand is waaaaaaaaaaaaaay more robust against all manner of failures and threats and really opens up the door for interstellar travel. HOWEVER.... Assume speed of light is an absolute limit. This means even short hops between stars take a really long time. This doesn't really get much better with increasing technology either, because the amount of computation and evolution we would expect for a sentient robot swarm likely increases faster or at least at the same rate to where, in relative time, it's probably always going to be long and expensive in terms of energy. Even worse... take two "individuals" within this civilization and separate them for 100 years, which is not an unreasonable estimate for interstellar travel. They will be separated for far longer in practical computation time and are likely to evolve substantially without a lot of communication over that time. They will be so different as to not even be the same kind by the time they rejoin. So any semblance of stability for a galactic civilization is such a massively unlikely assumption in my mind. Instead individuals are likely to be in competition with each other. This produces an incentive to prevent such travel from occurring to begin with.
- stevenhuang 5y ago
  If mind states can be streamed and integrated continuously while traversing those light years, that would make reintegration less of shock.
  - Enginerrrd 5y ago
    That's a hell of a network latency to contend with.
trainsplanes 5y ago
We've only barely detected that planets exist outside of our solar system fairly recently. Our observations are mainly limited to the general size of them, e.g. 1 Jupiter width, 2 earth masses, etc. Telescopic images of other stars in our galaxy are just a couple pixels. We're essentially blind but saying there's nothing to see. We don't yet have the technology to really observe what's happening in our galactic neighborhood. We don't even know what's going on under the atmospheres of the gas giants in our own solar system and it's mostly speculation. If another planet had a pipeline linking their planet to a star for pure plasma energy, we couldn't even observe that with today's tools. Another planet observing earth for intelligent life using our standards would also conclude that there's absolutely nothing here. Artificial lighting is under 200 years old, leaving little in the visible spectrum as an obvious sign of intelligent life for anything over 200 light years away. They could easily brush off oxygen/CO2 production as some sort of natural process. They could also conclude that the idea of life existing on earth for hundreds of millions of years is insanity, because clearly earthlings have planetary rodeos where we'd drag planets around for fun or we'd be using the methane on our gas giants for sustenance.

by cletus 5y ago

colordrops 5y ago

> superintelligent viruses What if some virus evolved to work super intelligently as a hive mind? > My personal view is that our knowledge of the Universe at this point isn't perfect but it's closer to correct than not. I think most of the evidence contradicts this. My suspicion is that if we continue to progress at the same rate or accelerate, in 1000 years we (assuming we are still recognizably human) will look back at our understanding of reality right now as nearly completely wrong. So your constraints don't seem to be givens. > My personal view is that there simply aren't any starfaring civilizations to find within a pretty large (1M+ light years) light cone. This makes a lot of assumptions, including that intelligent species don't accelerate quickly into something unrecognizable as they evolve to more advancement, or that our model of spacetime is basically right and there isn't much more to expand into besides our sparse region of reality.

kiba 5y ago
I think most of the evidence contradicts this. My suspicion is that if we continue to progress at the same rate or accelerate, in 1000 years we (assuming we are still recognizably human) will look back at our understanding of reality right now as nearly completely wrong. Most of the evidence? We haven't found any new physics phenomenon from which we can derive new technology. There's no known or theoretical ways for us to traverse to different realities let alone prove or disprove such existence, for example. This makes a lot of assumptions, including that intelligent species don't accelerate quickly into something unrecognizable as they evolve to more advancement, or that our model of spacetime is basically right and there isn't much more to expand into besides our sparse region of reality. Just because we can imagine something doesn't make it possible.
- colordrops 5y ago
  I'm referring to historical evidence. At any point in history other than recent, our understanding of reality has been completely revised since then. And the extrapolation is that the same trend will continue. We've got zero evidence whatsover that we've found core models that can't be overridden by further discovery, and eventually made obsolete in whole by large paradigm shifts.
  - Normal_gaussian 5y ago
    I will happily argue there is pretty strong historical evidence our models are correct. In my amateur trip through philosophy from Plato to Wittgenstein I've seen a lot of acknowledgements by the intelligencia of a generation as to what is presumed, convenient, or constructed fact and what is actual fact. Paradigm shifts in thinking have gotten repeatedly smaller over the written record, and would hardly be considered a paradigm shift by previous generations.
  - Delk 5y ago
    That would be true if the development of our understanding had happened at a linear pace. It hasn't, though. Our understanding of the physical universe has grown so much within the last hundred or couple hundred years that I'm not sure understanding had grown equally much even throughout the entire preceding human history. At least you'd have to go pretty far in history. With accelerating growth of understanding you will, at some point, get to "mostly correct". I don't know if we're there yet but you can't extrapolate linearly from history that we aren't.

achenatx 5y ago

Natural selection means that they likely are warlike and violent. Warlike and violent intelligent species destroy themselves quickly so are unlikely to exist at the same time as us. Only the ones that can reengineer themselves to not be warlike and violent before they destroy themselves will survive for long enough to exist at the same time as us. Therefore it is likely any intelligent species we meet will be peaceful (among themselves at least).

mpoteat 5y ago

My view is that we can reason about organisms living in space because we are one of them. We have a sample size of one, but assuming that properties of different space-faring organisms are distributed normally, it stands to reason that the first sample collected is near to the mean of the underlying distribution. In other words, imagine a normal distribution with very, very low variance (say, 0.0001). The mean is unknown to you. If you take one sample, your sample will very likely be close to the mean.

AnimalMuppet 5y ago
Within your argument, what's the justification for assuming low variance?
- mpoteat 5y ago
  There is none! Variance could be arbitrarily high I suppose. In the limit, if you assume a uniform distribution, I don't think that a single sample will give you any information about the underlying distribution characteristics. However, for the sake of the argument, variance can be arbitrarily high and still provide increasingly lower amounts of Bayesian evidence. As long as the variance is not unbounded (i.e. as long as the distribution is Gaussian, which I think is a reasonable assumption in nature), you can extract _some_ evidence from a single sample.

Enginerrrd 5y ago

Honestly, the idea of a coherent starfaring civilization is itself kind of dubious to me based on the following things: IMO, biological corporeal from for intelligence is not a longterm solution. Bodies are good at what the things they evolved to do and interstellar travel aint one of those things. Now downloading your consciousness onto a robot/computer/swam on the other hand is waaaaaaaaaaaaaay more robust against all manner of failures and threats and really opens up the door for interstellar travel. HOWEVER.... Assume speed of light is an absolute limit. This means even short hops between stars take a really long time. This doesn't really get much better with increasing technology either, because the amount of computation and evolution we would expect for a sentient robot swarm likely increases faster or at least at the same rate to where, in relative time, it's probably always going to be long and expensive in terms of energy. Even worse... take two "individuals" within this civilization and separate them for 100 years, which is not an unreasonable estimate for interstellar travel. They will be separated for far longer in practical computation time and are likely to evolve substantially without a lot of communication over that time. They will be so different as to not even be the same kind by the time they rejoin. So any semblance of stability for a galactic civilization is such a massively unlikely assumption in my mind. Instead individuals are likely to be in competition with each other. This produces an incentive to prevent such travel from occurring to begin with.

stevenhuang 5y ago
If mind states can be streamed and integrated continuously while traversing those light years, that would make reintegration less of shock.
- Enginerrrd 5y ago
  That's a hell of a network latency to contend with.

trainsplanes 5y ago

We've only barely detected that planets exist outside of our solar system fairly recently. Our observations are mainly limited to the general size of them, e.g. 1 Jupiter width, 2 earth masses, etc. Telescopic images of other stars in our galaxy are just a couple pixels. We're essentially blind but saying there's nothing to see. We don't yet have the technology to really observe what's happening in our galactic neighborhood. We don't even know what's going on under the atmospheres of the gas giants in our own solar system and it's mostly speculation. If another planet had a pipeline linking their planet to a star for pure plasma energy, we couldn't even observe that with today's tools. Another planet observing earth for intelligent life using our standards would also conclude that there's absolutely nothing here. Artificial lighting is under 200 years old, leaving little in the visible spectrum as an obvious sign of intelligent life for anything over 200 light years away. They could easily brush off oxygen/CO2 production as some sort of natural process. They could also conclude that the idea of life existing on earth for hundreds of millions of years is insanity, because clearly earthlings have planetary rodeos where we'd drag planets around for fun or we'd be using the methane on our gas giants for sustenance.