Science
15 Oct 15
22 Oct 15
Originally posted by googlefudgeStill, that would by definition be a one way trip, probably for colonization purposes. Suppose you had to go 30 billion light years, for one thing, would the universe even have habitable spaces by then? Our sun would be a well spread out cloud of dust by then and its daughter stars, granddaughter stars and great granddaughter stars would all be dust after THAT much time.
If your conciousness is embedded in computing substrate, billions of years is not a problem.
Also, what about the long term? What do they do when the star runs out of hydrogen? I think they had better be thinking about cut an run as the star would start to expand and sooner or later would be bigger than whatever Dyson sphere they had built.
23 Oct 15
Originally posted by sonhouseBut you still have enough energy to keep you going past what otherwise would be the heat death of the universe - assuming moderate energy use and no really significant increase in population in the meantime. As long as our population doesn't increase by more than a factor of a million or so we can survive as a species for trillions of years on the cumulative total power output of the sun. Even as a white dwarf the sun'll shine enough to keep us in power surplus for something like a trillion years.
Still, that would by definition be a one way trip, probably for colonization purposes. Suppose you had to go 30 billion light years, for one thing, would the universe even have habitable spaces by then? Our sun would be a well spread out cloud of dust by then and its daughter stars, granddaughter stars and great granddaughter stars would all be dust after T ...[text shortened]... d start to expand and sooner or later would be bigger than whatever Dyson sphere they had built.
Class 3 civilizations should be able to use the entire energy output of their entire galaxy. Really my objection to this is not due to lack of potential it's entirely a matter of feasibility. Once it's set up it's great, but setting it up is close to impossible.
23 Oct 15
Originally posted by DeepThoughtI think it safe to rule out using entire galaxies as energy sources for sure. Besides, we are still in our infancy of physics, which has only been around for a couple thousand years at best, compare that to the age of Earth. The exponential growth in physics has only been around for about 100 to 200 years. a sniff in the time line of Earth, much less the universe.
But you still have enough energy to keep you going past what otherwise would be the heat death of the universe - assuming moderate energy use and no really significant increase in population in the meantime. As long as our population doesn't increase by more than a factor of a million or so we can survive as a species for trillions of years on the cumul ...[text shortened]... a matter of feasibility. Once it's set up it's great, but setting it up is close to impossible.
The gist of that statement is this:
We have no idea where physics will be in another 100 years much less 1000 years or 1 million years assuming we as a civilization don't off ourselves in the meantime.
So given that we might be around after a thousand more years of growth in the sciences, we can't in all honesty say whether a Dyson sphere is even what would happen in an advanced civilization.
My guess is it would be a last resort effort.
My guess is that some other means of extreme energy will be found that obviates the need for a Dyson sphere in the first place, like my dream physics:
We find a simple almost energy free way to convert matter into anti-matter and then it is a simple matter to just combine the two to generate as much energy as anyone would ever want, a LOT more then would ever come out of a star, pound for pound.
Or something out of quantum physics tapping vacuum energy or some such.
I think it more likely that some kind of scientific development like that is much more likely to come about negating the need for any kind of large scale structure like a Dyson sphere.
With matter/antimatter generators, you only need micrograms of conversion for a person to have all the energy one would ever need for heating, cooling, cooking, transportation and industry, most industries anyway, for the heavy stuff you might even need a couple of MILLIgrams🙂
So my bet would be on the future advancement of physics we can barely imagine today.
Hyper super insulators, where one mm would equal 100 meters of blown glass insulation capable of holding off 100,000 degrees C on one side and absolute zero on the other side, hyper conductors where you get zero resistivity and full Meissner magnetic effects but working at 5000 degrees C and such for starters.
Supermagnetism like 1000 tesla magnets making tiny fusion reactors a reality.
Those are just the wish list of ordinary physics, not even going into exotic quantum effects like a real wormhole into other universes or a billion light years from home kind of thing.
24 Oct 15
Originally posted by sonhouseIf you've spread out enough to get at the central black hole you can extract a healthy fraction of that just by taking energy from the jets. I don't think the Kardashev (?) categorization really works either. A better technologically focused categorization would look at how much energy a civilization can focus onto a single project on some kind of log scale. The thing with the Kardashev scale is you have some chance of detecting them with current technology and categorizing them. Whereas you're not going to notice the presence of a civilization with the same capabilities as we do from a couple of hundred parsecs, so a scale based on my suggestion is far too fine grained.
I think it safe to rule out using entire galaxies as energy sources for sure. Besides, we are still in our infancy of physics, which has only been around for a couple thousand years at best, compare that to the age of Earth. The exponential growth in physics has only been around for about 100 to 200 years. a sniff in the time line of Earth, much less the un ...[text shortened]... ects like a real wormhole into other universes or a billion light years from home kind of thing.
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04 Nov 15
Originally posted by DeepThoughtApparently it wouldn't be the first planet/object found not gravitationally bound to a host star.
I had to look that up, yes, although the theoretical prediction and measured values are slightly different. The theoretical prediction is that Jupiter is only slightly below the upper radius limit. The measured maximum is about 1.5x the radius - see figure 4 on page 22 of [1] and I was looking at a log scale so that's a bit of a guess. Other than not ...[text shortened]... he first observed object not associated with a star.
[1] http://arxiv.org/pdf/0707.2895v1.pdf
I just came across this...
http://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-34712877
04 Nov 15
one way to get free energy from the expansion of the universe is to have a rope a few million light years long (easy, right?) and have it rolled up at one end and then have a giant weight at the other end, say tethered to the north or south pole of a dead planet and the expansion of the universe will pull the rope and you have a generator tied to the pulley and viola!, instant power.
05 Nov 15
8 edits
Originally posted by sonhouseTo stop the universe from expanding to become undesirably ever more sparse of matter, we should over a few million years construct a system of ropes between all the galaxies in the whole universe to stop them flying apart (I leave the tedious technical details of how to attach each end of each rope to a whole galaxy to those who are in-the-know about this sort of thing ).
one way to get free energy from the expansion of the universe is to have a rope a few million light years long (easy, right?) and have it rolled up at one end and then have a giant weight at the other end, say tethered to the north or south pole of a dead planet and the expansion of the universe will pull the rope and you have a generator tied to the pulley and viola!, instant power.
But then to stop them being all pulled together under their own collective gravity into an undesirably big crunch, we should then construct a system of rigid struts between all the galaxies to stop them coming towards each other. I suggest we should rearrange the relative positions of all the galaxies into a fairly evenly-spaced but aesthetically pleasing patterned arrangement, perhaps with lots of pleasingly hexagonal and pentagonal arranged groups of galaxies. I estimate that this will cost around $10^1000000 so we will just have to save up for it and wait until our economy improves somewhat. I personally think both the UK and US economy should contribute. This is all assuming some smart-ass aliens haven't already shamed us by starting the construction of all this already i.e. beat us to it.
Perhaps I should make this suggestion to NASA?
05 Nov 15
1 edit
Originally posted by humyJust make sure the rope is very strong and leave the ends close the event horizons of the central black holes of the two galaxies and everything should hang together.
To stop the universe from expanding to become undesirably ever more sparse of matter, we should over a few million years construct a system of ropes between all the galaxies in the whole universe to stop them flying apart (I leave the tedious technical details of how to attach each end of each rope to a whole galaxy to those who are in-the-know about this sort ...[text shortened]... uction of all this already i.e. beat us to it.
Perhaps I should make this suggestion to NASA?
Edit: the rope also needs to be able to resist collisions with stars and intermediate and stellar mass black holes, which could turn out to be the problem with the plan.
05 Nov 15
1 edit
Originally posted by DeepThoughtBah, just simple engineering problems🙂
Just make sure the rope is very strong and leave the ends close the event horizons of the central black holes of the two galaxies and everything should hang together.
Edit: the rope also needs to be able to resist collisions with stars and intermediate and stellar mass black holes, which could turn out to be the problem with the plan.
Anyway, to get long term use you need to just keep adding rope in between sections cut out so you keep getting new rope for more energy.