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Existing laser tech could be used for “porch light” to attract alien astronomers

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Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#61

Post by jessaustin »

Johnny555 wrote: post #60
jessaustin wrote: post #59

Earlier quoted context omitted.

Your example sort of fell apart there. It took 180 days at some hypothetical moment in history. Now it takes a few days. There are a few words in English the meaning of which is absolute, regardless of context. "Few" is not among those words.

Few doesn't have an absolute meaning, but it does have a consistent relative meaning. You could take a handful of sand from a sand dune and say "I took only a few grains of sand home with me" You could say "only a few of the thousands of visible stars are close enough to send a signal to" even if that means hundreds. But you wouldn't say "it takes 40 light years to reach the star, so the laser can reach it in a few y…

Now you've got it! Yes, "few" in this case is 40, just as in the sand example you've given it is maybe a few hundred thousand. Just as interstellar communication might take thousands of years, the sand dune might have contained billions of grains. Context is important!

NB: The light-year is a measure of distance, not of time.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#62

Post by Johnny555 »

jessaustin wrote: post #61
Johnny555 wrote: post #60

Earlier quoted context omitted.

Few doesn't have an absolute meaning, but it does have a consistent relative meaning. You could take a handful of sand from a sand dune and say "I took only a few grains of sand home with me" You could say "only a few of the thousands of visible stars are close enough to send a signal to" even if that means hundreds. But you wouldn't say "it takes 40 light years to reach the star, so the laser can reach it in a few y…

Now you've got it! Yes, "few" in this case is 40, just as in the sand example you've given it is maybe a few hundred thousand. Just as interstellar communication might take thousands of years, the sand dune might have contained billions of grains. Context is important! NB: The light-year is a measure of distance, not of time.

And now refer back to the original quote:

especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth, or TRAPPIST-1, a star about 40 light-years away that hosts seven exoplanets, three of which are potentially habitable. If the signal is spotted from either of these nearby systems, the study finds, the same megawatt laser could be used to send a brief message in the form of pulses similar to Morse code.....“If we were to successfully close a handshake and start to communicate, we could flash a message, at a data rate of about a few hundred bits per second, which would get there in just a few years,”

And you'll see my point that you wouldn't say you can reach a star that's 40 light years away in "just a few years" when "just a few years" is 40.

Note that the starting number was 40, and the "to be compared with" number was 40. 40 is not "a few" of 40.

And yeah, I was a little sloppy in using "light years" as time.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#63

Post by jessaustin »

Johnny555 wrote: post #62
jessaustin wrote: post #61

Earlier quoted context omitted.

Now you've got it! Yes, "few" in this case is 40, just as in the sand example you've given it is maybe a few hundred thousand. Just as interstellar communication might take thousands of years, the sand dune might have contained billions of grains. Context is important! NB: The light-year is a measure of distance, not of time.

And now refer back to the original quote: especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth, or TRAPPIST-1, a star about 40 light-years away that hosts seven exoplanets, three of which are potentially habitable. If the signal is spotted from either of these nearby systems, the study finds, the same megawatt laser could be used to send a brief message in…

That's not a point. You deliberately misinterpreted and continue to misinterpret the clear meaning of the text. Thanks for wasting my time.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#64

Post by Johnny555 »

jessaustin wrote: post #63
Johnny555 wrote: post #62

Earlier quoted context omitted.

And now refer back to the original quote: especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth, or TRAPPIST-1, a star about 40 light-years away that hosts seven exoplanets, three of which are potentially habitable. If the signal is spotted from either of these nearby systems, the study finds, the same megawatt laser could be used to send a brief message in…

That's not a point. You deliberately misinterpreted and continue to misinterpret the clear meaning of the text. Thanks for wasting my time.

I was pretty clear about my point in my original post, and even quoted the sentence in question.

Though it's disingenuous to reply multiple times to a HackerNews post to make a trivial point and then complain about wasted time -- you choose how to spend your time.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#65

Post by antepodius »

sebazzz wrote: post #47
paulsutter wrote: post #41

Earlier quoted context omitted.

Quoting the link > Like hunters in a "dark forest" ... where any two civilizations cannot communicate well enough to relieve mistrust, making conflict inevitable. Therefore, it is in every civilization's best interest to preemptively strike and destroy any developing civilization before it can become a threat, but without revealing their own location, thus explaining the Fermi paradox.

I think the explanation of the Fermi paradox is the fact that without a natural predator and add technically superior intelligence we populate the entire planet, while also having little care for the environment causing global warming which is then a problem handled too little too late (or even denied) by our politicians around the globe. This can eventually cause conflict, especially when food prices become too high…

Why would you kill an ant? Would you care if one died while workers were building an orphanage?

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#66

Post by antepodius »

beerlord wrote: post #44
village-idiot wrote: post #23

Are they fucking crazy? Turn out that light! Our first encounter with space faring aliens will probably go about as well as native Americans first encounter with Europeans.

The value that Earth provides is the fact that it hosts millions of living species. Mere geological resources can be gathered from asteroids or other planets with lesser gravity wells. The Alien species would have to determine if Human technology, economy and culture holds any value to them. If it does, they will conduct a cost-benefit analysis of the various billions of humans inhabiting the planet, and eliminate th…

If we're talking about intelligences that can travel between stars, there is no 'carrying capacity' aside from space on the surface for radiative cooling towers to stop the planet from boiling from the heat generated by the trillions of humans and machines. Seriously, you can probably put all the nonhuman processes of an ecosystem into a bottle that takes in air, energy, and wastewater and puts out food/crops/etc, and you can just dismantle some asteroids for the materials needed for as many fleets of solar panels as you need to put around earth, assuming they don't want to use what's powering their rockets. Really, the limiting factor is cooling the earth. You'd probably want to block all infrared from the sun for convenience.

Implying these beings would likely have any need to worry about 'decreasing' carbon emissions is ludicrous. It's like humans going to a beehive and worrying about killing some bees to stop honey wastage when the humans poke a hole in the hive to collect honey- no, they'll just completely reconstitute the hive. There's a chance it's some first-interstellar-travel thing we might do right now, but it's more likely it's from the time a civilisation is kardashev-2, given that time would be longer. Fermi paradox's still a problem, though.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#67

Post by antepodius »

crobertsbmw wrote: post #26

How we would agree on a handshake? Aliens don’t know English let alone Morse code.

What would we do if we detected a big glob of binary? Try and look at it in everywhich way. And we would as well if it was stranger.

Re: Existing laser tech could be used for “porch light” to attract alien astronomers

#68

Post by BrandoElFollito »

gisely wrote: post #33
ALittleLight wrote: post #18

Earlier quoted context omitted.

For being such a cynic about humanity you're awfully optimistic about aliens.

I think there might be some reasons to be optimistic. Any civilization that might notice our signal and decide to interact with us has with us has existed much longer than our own civilization with high probability. Thus, there is more evidence of long-term stability in such a civilization than our own. With stability comes the potential for experience, with experience the potential for wisdom.

Old movie spoilers ahead

I watched a short movie (an episode from the Outer Limits? It was ~20 years ago) about some army rangers who stumble upon, track and ultimately kill an alien.

When observing it closely afterwards, they realized it was an alien child sent to Earth on some kind of children camp.

The primitive livings on that planet killed the child. The parents were not happy, blew up the camp (and our planet).

So yes, I also favor the Dark Forest approach

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