4 ms·

I'm in a more conservative camp than speed limits: the practicality one. Even if we ignore the ponies and rainbows of wormhole travel, if you want to travel to

I'm in a more conservative camp than speed limits: the practicality one. Even if we ignore the ponies and rainbows of wormhole travel, if you want to travel to a plain black hole to use the magic teleporter, the nearest two are V616 Mon at 11 solar masses and 3000 LY away, and Cyg X1 at 15 SM and 6000 LY. If you buy into the article's assertion that you won't get burned or spaghettified on your way to becoming a nucleon paste, and you want a heavier BH, the nearest is Sag A* at 4.1e6 SM and 25000 LY away. Anyway, to travel between the teleporter and Earth, we're talking most of the resources of a planet to accelerate a mass to substantial fractions of c. Then you've got thousands of years of collisions, radiation, and maybe (assumption?) cultural and biological challenges of living in space for aeons, plus needing another planet's worth of resources to slow down at the destination. All this makes it hard enough even to get a dozen LY to our nearest start system. My opinion is we're in something of a Well World universe, where everyone is pretty well travel-isolated from their neighbors.

arbuge 8y ago
> the nearest two are V616 Mon at 11 solar masses and 3000 LY away, and Cyg X1 at 15 SM and 6000 LY. The nearest known ones, that is. They were detected due to their gravitational effect on binary companions we could more easily detect. By that token, it is quite possible there are nearer ones - it's just that detecting them directly if they don't have a binary companion is tough.
- empath75 8y ago
  Could be one on a collision course with us right now.
jvanderbot 8y ago
The author didn't mention using black holes to get around. Hyperspace might be just moving into wherever the events in the movie Event Horizon took place.
- krapp 8y ago
  Isn't Event Horizon basically just a horror movie, except the haunted house is a spaceship? If you're going to pick a fictional hyperspace "framework," there are many to choose from, all of which are equally nonsensical.
deleted 8y ago
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wallace_f 8y ago
Very interesting, but this assumes life evolves to Type II civ. I mean, looking at our own planet, it seems this might be extremely unlikely. To the best of my knowledge, another Planet Earth could possibly be within a few hundred ly of us(0.000000001 of known universe), and we'd have no idea(1)..? 1-https://www.centauri-dreams.org/2012/05/31/is-our-civilization-detectable/ https://www.centauri-dreams.org/2012/05/31/is-our-civilizati...
adrianN 8y ago
Artificially creating microscopic black holes is not extremely difficult [1], and after that you can "just" feed them a few stars. Probably you can harvest them while travelling less than 25000 LY. [1] Section V of this paper https://arxiv.org/abs/0908.1803 https://arxiv.org/abs/0908.1803
- the-great-assyr 8y ago
  Nice. Can you make one for us, please?
- v_lisivka 8y ago
  You can feed 1 star into 1 BH.
tachyonbeam 8y ago
I hear you, but I think colonizing the galaxy might still be feasible. If we can get to the point where we have the technology to colonize Mars, which will hopefully happen this century, then I would imagine it probably won't be long after that until we manage to have permanent space habitats that harvest materials from asteroids. If we have fusion power, durable permanent space habitats, and the technology to harvest materials from asteroids, then traveling to the next star system doesn't seem so far-fetched anymore. If we could just reach 0.1c, we could make it to Alpha Centauri in less than 50 years. Once we make it there, if we're already comfortable living in space, we don't even need to worry about terraforming or anything lengthy and complicated like that, we can just harvest asteroids and build more space stations and ships. Not a physicist, but I see Project Orion could have reached 0.33% of the speed of light. Would it be realistic to extend that design to accelerate to 0.1c?
- wongarsu 8y ago
  Using hydrogen bombs you can get something like Project Orion to about 10% the speed of light, but not much faster. Project Daedalus is a more advanced design with the goal of accelerating an unmanned probe to 12% the speed of light [1]. The only somewhat practical ideas that seem to go beyond that involve antimatter fuel: not quite as easy to handle and well understood as nuclear bombs but certainly more attainable than giant black holes. There are a few designs that should allow travel at 60-80% the speed of light 1: https://en.wikipedia.org/wiki/Project_Daedalus https://en.wikipedia.org/wiki/Project_Daedalus
  - Tepix 8y ago
    Isn't fusion power a promising technology to provide the energy needed to accelerate (and decelerate) for a long time?
    - ljcn 8y ago
      Not my area but I think the fuel is the problem, not the power source. Even a fusion-powered drive needs to spit something out the back to accelerate (e.g. ions), so you need to carry many kg of ionizable fuel.
YeGoblynQueenne 8y ago
>> My opinion is we're in something of a Well World universe, where everyone is pretty well travel-isolated from their neighbors. Let us hope so.

arbuge 8y ago

> the nearest two are V616 Mon at 11 solar masses and 3000 LY away, and Cyg X1 at 15 SM and 6000 LY. The nearest known ones, that is. They were detected due to their gravitational effect on binary companions we could more easily detect. By that token, it is quite possible there are nearer ones - it's just that detecting them directly if they don't have a binary companion is tough.

empath75 8y ago
Could be one on a collision course with us right now.

jvanderbot 8y ago

The author didn't mention using black holes to get around. Hyperspace might be just moving into wherever the events in the movie Event Horizon took place.

krapp 8y ago
Isn't Event Horizon basically just a horror movie, except the haunted house is a spaceship? If you're going to pick a fictional hyperspace "framework," there are many to choose from, all of which are equally nonsensical.

deleted 8y ago

[deleted]

wallace_f 8y ago

Very interesting, but this assumes life evolves to Type II civ. I mean, looking at our own planet, it seems this might be extremely unlikely. To the best of my knowledge, another Planet Earth could possibly be within a few hundred ly of us(0.000000001 of known universe), and we'd have no idea(1)..? 1-https://www.centauri-dreams.org/2012/05/31/is-our-civilization-detectable/ https://www.centauri-dreams.org/2012/05/31/is-our-civilizati...

adrianN 8y ago

Artificially creating microscopic black holes is not extremely difficult [1], and after that you can "just" feed them a few stars. Probably you can harvest them while travelling less than 25000 LY. [1] Section V of this paper https://arxiv.org/abs/0908.1803 https://arxiv.org/abs/0908.1803

the-great-assyr 8y ago
Nice. Can you make one for us, please?
v_lisivka 8y ago
You can feed 1 star into 1 BH.

tachyonbeam 8y ago

I hear you, but I think colonizing the galaxy might still be feasible. If we can get to the point where we have the technology to colonize Mars, which will hopefully happen this century, then I would imagine it probably won't be long after that until we manage to have permanent space habitats that harvest materials from asteroids. If we have fusion power, durable permanent space habitats, and the technology to harvest materials from asteroids, then traveling to the next star system doesn't seem so far-fetched anymore. If we could just reach 0.1c, we could make it to Alpha Centauri in less than 50 years. Once we make it there, if we're already comfortable living in space, we don't even need to worry about terraforming or anything lengthy and complicated like that, we can just harvest asteroids and build more space stations and ships. Not a physicist, but I see Project Orion could have reached 0.33% of the speed of light. Would it be realistic to extend that design to accelerate to 0.1c?

wongarsu 8y ago
Using hydrogen bombs you can get something like Project Orion to about 10% the speed of light, but not much faster. Project Daedalus is a more advanced design with the goal of accelerating an unmanned probe to 12% the speed of light [1]. The only somewhat practical ideas that seem to go beyond that involve antimatter fuel: not quite as easy to handle and well understood as nuclear bombs but certainly more attainable than giant black holes. There are a few designs that should allow travel at 60-80% the speed of light 1: https://en.wikipedia.org/wiki/Project_Daedalus https://en.wikipedia.org/wiki/Project_Daedalus
- Tepix 8y ago
  Isn't fusion power a promising technology to provide the energy needed to accelerate (and decelerate) for a long time?
  - ljcn 8y ago
    Not my area but I think the fuel is the problem, not the power source. Even a fusion-powered drive needs to spit something out the back to accelerate (e.g. ions), so you need to carry many kg of ionizable fuel.

YeGoblynQueenne 8y ago

>> My opinion is we're in something of a Well World universe, where everyone is pretty well travel-isolated from their neighbors. Let us hope so.