Posted on 03/16/2018 9:36:20 PM PDT by LibWhacker
“If you could build a craft that could travel at or near the speed of light you just can’t just ‘’hit the brakes’’ like it was a car. If you did you’d be a smear on the inside wall/bulkhead or what ever of your ship.”
That’s what inertial dampeners are for. Duh.
Good point. Going from 0.8c to 0 in a stopping distance of a few hundred AU... the deceleration forces alone would probably kill you.
Fuel and transport cost money, so even if Proxima Centauri is having a sale on Unobtainium for $1/pound, when you include shipping the cost will be $100,000,000,001.
I don't think interstellar commerce would work like that. The reason is that you don't wait 50 years for the next delivery. You have a ship launch every year and pretty soon your delivery time frames are annual. Yes, there's a big jump for the first batch but after that the time frame dwindles. There is always the option of a lost ship or goods exposed to space, but then you would only ship the most durable items anyway.
Without inter-dimensional travel, there is no possible way to conduct commerce with other star systems, let alone other galaxies.
You need to able to go from one point to another and back within a reasonable amount of time.
Higher dimensions allow virtual instant travel time between two points. I’m sure some brainiac will find the secrete in the future.
Read a sci-fi short once where some advanced civilizations would automatically attack any other such they encountered because the other was completely inscrutable, unpredictable and as such posed an unacceptable existential threat. No time to study them. You snooze, you lose. Instantaeous annihilation for just revealing your presence. Totally creeped me out.
See Cixin Liu’s The Three Body Problem, The Dark Forest and Deaths End.
What you relate is the Dark Forest Theory. If you make noise in the forest, predators will hear and come for a meal.
It this story the predators do not actually come to the meal but being cautions lest other predators hear them, send a seed which grows to encompass the entire solar system and converts it into a 2-dimensional object. Problem solved. Predator remain hidden.
“Of all the gin joints in the universe....bar fight”
;>)
Aren’t you putting the cart before the horse, as it were?
I wonder what would happen if you were going .5c and ran head on into another object that was going .5c ?
So... where would you keep that light sail, in the glovebox ? How many crew members would it take to unfurl it ?
OY! It would be such a mess!
You’d want to keep the acceleration/deceleration at or below 1g if humans were aboard, especially for the length of time it takes to go to and from 0.8 light speed. To get there at 1g, it would take 283 days, and covering a distance of 19,600 AU’s (0.31 ly). Double that for the deceleration leg. But where does a spaceship get the energy to do this, keeping in mind that the more fuel you’re carrying, the heavier and slower your spaceship will be? I can’t imagine doing it with anything less than some futuristic super fuel like antimatter.
Thanks fieldmarshaldj for the ping, LibWhacker for the topic. Definitely want to check the sell-by dates. Unless the trade is in cryptocurrency.
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Interesting article. It mentions mining asteroids. Think that would have a quicker return on investment. Few if any of the technologies discussed exist yet, but they’re not far off. At least not in terms of a civilization. His math seems solid.
That, or we could just invent a warp drive. This is not entirely snark. I know at least two people who are seriously working on the physics behind actually doing so. The trick is that while matter or energy cannot move faster than the speed of light, space itself can.
Time dialation actually works the other way around. If you are on a ship moving at .9c and going to a system 10 light years away and back, from the outside it will look like the round trip takes 18 years. From the inside of the ship it will take a lot less. (Sorry, too lazy to do the math on a Saturday.)
It’s worse. If you are going 0.5c and run into a stationary 1 gram dust particle, the released energy from impact will basically be equivalent to a large nuke.
Pedal to the metal. Is better to 'push through' the impact. Go Full Light Speed, or faster. Then the energy can't catch you.
; )
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