4 ms·

Unfortunately, this idea has been explored and discarded. Thermodynamics requires the emission of detectable EM energy from such shells, just at longer waveleng

Unfortunately, this idea has been explored and discarded. Thermodynamics requires the emission of detectable EM energy from such shells, just at longer wavelengths. We'd expect to see dark matter emitting in microwave or IR, but we don't.

CamperBob2 10y ago
It doesn't require that a Dyson Sphere be an isotropic radiator, though. It could be emitting its heat in a different direction.
- breischl 10y ago
  Well, if you emitted it all in a beam away from the plane of your galaxy, that might make you very stealthy. That would impart thrust on the sphere... which if it wasn't perfectly balanced might cause it to wobble, and then start rotating... ... and now we have a sci-fi reason for quasars. :)
  - Semiapies 10y ago
    You could direct the waste in two beams perpendicular to the plane of the galaxy, in order to balance net thrust. I question how stealthy that would really make you, though. If someone was bothering to look for stealthy civilizations, they'd just have to scatter some observatories around their region of the galaxy, then watch. Eventually, your structure would occult a star from the POV of one of those observatories, or they'd pick up your beam scattering in interstellar gasses or dust clouds.
    - breischl 10y ago
      Of course you'd need two beams. If you used a single beam it would be a stellar rocket... which might be fun in different ways. Certainly gives the phrase "interstellar warfare" a different meaning. I realize this is all space opera, not hard SF. It's still fun.
      - Mtinie 10y ago
        "But Sir, these are the correct stellar coordinates for the Zorgoph home world! They should be right here!" "There's nothing here, Captain. Nothing at all. So you're saying that they moved an entire star system? In the last solar cycle?" Good times, good times.
    - Grishnakh 10y ago
      Maybe they figured out how to create an artificial wormhole and direct their waste heat into that....
tremon 10y ago
buzzkill ;)

CamperBob2 10y ago

It doesn't require that a Dyson Sphere be an isotropic radiator, though. It could be emitting its heat in a different direction.

breischl 10y ago
Well, if you emitted it all in a beam away from the plane of your galaxy, that might make you very stealthy. That would impart thrust on the sphere... which if it wasn't perfectly balanced might cause it to wobble, and then start rotating... ... and now we have a sci-fi reason for quasars. :)
- Semiapies 10y ago
  You could direct the waste in two beams perpendicular to the plane of the galaxy, in order to balance net thrust. I question how stealthy that would really make you, though. If someone was bothering to look for stealthy civilizations, they'd just have to scatter some observatories around their region of the galaxy, then watch. Eventually, your structure would occult a star from the POV of one of those observatories, or they'd pick up your beam scattering in interstellar gasses or dust clouds.
  - breischl 10y ago
    Of course you'd need two beams. If you used a single beam it would be a stellar rocket... which might be fun in different ways. Certainly gives the phrase "interstellar warfare" a different meaning. I realize this is all space opera, not hard SF. It's still fun.
    - Mtinie 10y ago
      "But Sir, these are the correct stellar coordinates for the Zorgoph home world! They should be right here!" "There's nothing here, Captain. Nothing at all. So you're saying that they moved an entire star system? In the last solar cycle?" Good times, good times.
  - Grishnakh 10y ago
    Maybe they figured out how to create an artificial wormhole and direct their waste heat into that....

tremon 10y ago

buzzkill ;)