Yeah, I'm far behind in general phone-fu, there may well be fairly simple ways to accomplish that here, it just seems like the convenience store route is not so easy. As I say, I'm far from sure it is legally mandated, VT usually has pretty lax regulations on stuff like that (no gun laws at all basically beyond "don't shoot in the direction of houses or in town!", etc). I guess you could certainly buy a phone at various box stores without a plan, they're happy to take your money. Verizon I KNOW will not activate a smart phone without a data plan though, and for that they require a contract, which means a John Hancock etc. AT&T and Sprint etc exists, and Sprint in particular is pretty lose on plans and contracts, you can definitely activate a phone without a contract and buy data service. The coverage sucks and good luck getting 3G, let alone 4G, but perhaps you can buy minutes without getting IDed. No doubt where there is sufficient will there is a way...
Well, I can't speak for other areas of the US or other countries, but in Vermont you MUST present ID to buy a pre-paid. Dunno if that's a legal requirement or what, but its universal, they record your ID before they will activate the phone. I don't doubt that if you slipped a convenience store clerk a few bills they'd scare you up a phone that wasn't linked to you, and there are plenty of homeless people wandering around with phones, etc you can probably acquire with minimal effort if you REALLY want to. Its just not as simple as paying cash.
No, they CALL the number and verify your information. That means, unless you've figured out a way to get anonymous 'burner' phone in the US that actually works, you'll be associated with the AWS account. Obviously if you're REALLY determined it IS possible to get active phones that aren't linked to you, but it isn't exactly easy and can raise the suspicion of law enforcement itself.
Of course if your goal is to provide proxy/tor services for people overseas none of this matters anyway.
How long would it be before all of AWS was just blocked at the national firewall level? Its not like these regimes give a crud what else they accidentally block. Most of them would as soon just block the whole thing if they could...
Actually maybe even before that, it happened incrementally. Back in the mid-60's my Father and his business partner had a consulting firm they ran out of the basement. They built all sorts of custom hardware for mostly the Air Force. He taught me basic electronics, and then when he went to work for another larger company we'd go into work on Saturday and I'd type in FORTRAN programs onto punch cards for him (but I didn't know what they did exactly). Eventually, sometime circa 1970 he was working for a place where most of what he worked on was software, and I'd play around with the PDP-11C (which had a tty). You could run BASIC and interact, so by age 7 I could use the computer like a calculator.
It wasn't until later that I really learned to seriously program. In high school we actually had A computer (TRS-80 Model 1 IIRC) which I finagled the librarian to let me play with, and I learned at least a bit. My uncle also gave us a typesetting machine that you could program in assembler using CP/M and reading the PACE assembler book I finally got the key concepts. The year after that I went to college and took FORTRAN. Hard to say in there where exactly i got to "can program" from "cannot program" but I'm sure in this day and age it would be MUCH easier and happen sooner.
Why would you ever need to BUY anything? I have at least 3 or 4 decent video editors that are free I can install in 5 minutes that for the level of stuff you can do with an online suite are perfectly fine. The 'article' (aka slashvertisment) is putting up a false dichotomy between pay software and a free webapp when nobody in their right mind that doesn't have at least pretensions to serious video editing has PAID for their software in a while now.
My my, and we must suppose you kiss your mother with that mouth too!
I know of no general principle which would make me conclude that message passing is safer than making system calls. In fact they offer pretty much exactly the same sorts of dangers. Much the same argument was touted by virtualization technology providers, and it hasn't proven particularly hard for exploit developers to worm their way from application to guest OS to hypervisor. I'm not at all convinced that microkernels are inherently any safer than monolithic kernels in any practical sense.
As for having more levels of privilege... There are various questions there, one being exactly what containment hierarchy is appropriate? But ultimately its the same old question all over again, how do you guarantee that the messages containing data passing between different sandboxes are benign? Why is it necessary to have a microkernel design in order to achieve this?
Finally, why in fact are you reacting as if I have badmouthed you or the concept of microkernels? I only stated that Hurd is rather obsolete at this point. Mach has been around since the 1980's and while a lot of things haven't changed THAT much its pretty clear that system architectures are evolving rapidly and are mostly held back now by software. Wouldn't it make more sense to develop an OS that was forward looking? IMHO it would draw from a wide range of experience with OSes of all types and incorporate some brand new ideas that are probably needed in order to move into the VERY many-core heterogeneous future.
Even more Finally: I don't think the answer to security issues like malware are going to be found in cleverer software designs. I think the ultimate 'solution' (and it may not look much like a solution to us) will be social and economic. Better software is clearly something we want, but its not THE solution, the bad guys will always have an almost insurmountable advantage in that realm.
Yeah, I don't know. I can't even pretend to be any more than superficially informed about modern OS design. There was a day when I worked on bare metal and RTOSes, ported FORTH to new processors and such things, but its been 25 years now. I understand that people have developed some more useful communications techniques and that a lot of the issue is CPU designs that assume a monolithic kernel architecture and aren't kind to things like microkernels. I know from casual skimming there are various areas of active research. It would seem like in the future we're likely to have dozens or 100's of cores, at which point dedicating one to running your USB port doesn't seem terribly ridiculous and I'd think that would obviate some of the context-switching issues with current designs.
Yeah, he's a bit out there, but it would be incredibly hypocritical not to give credit where due. The guy is clearly the prime mover behind a lot of free software. I'm sitting here typing this on my nice FC17 system in Firefox and using all sorts of FSF software practically every hour of the day to run my business etc. The world needs guys like RMS, even if it doesn't seem to know it or appreciate them a whole lot. In my world one RMS is worth 12 Bill Gateses.
If you're interested in understanding microkernel OS architectures, then Hurd might be useful to experiment with. Other than that its pretty close to unusuable as there isn't even basic SATA and USB support (IE you're going to have to install on OLD hardware, or much more likely in a VM where you can supply virtualized IDE).
Honestly, while I certainly don't want to rain on anyone's pet project Hurd has mostly become pointless. Its user space really offers nothing beyond what Linux or other POSIX *nix user spaces offer, and while microkernels are interesting concepts they've never proven to be terribly practical in most applications. Even in terms of microkernel design Hurd is dated. I'd think it would be much more interesting to work on future-looking OSes, say something with a Plan 9-like user space and some more modern experimental kernal with features designed around high core counts and heterogeneous compute resources. Not sure what that is, but I'm sure there are people out there working on stuff like that.
A list of patentable features of the algorithm would be right at the top of my list as well. If you can also show lack of existing patents covering any aspects of your code that would be good too.
Eh, yeah, well, we can only discuss things within the context of our own knowledge and experiences, that's true. I'm not entirely convinced that we have 'no idea' though. I think in terms of knowing what things are likely to be physically possible we're in a lot better shape than the people of 1000 years ago. I'm reminded of Isaac Asimov's famous essay where he talks about there being a HUGE difference between virtually no data and having a lot of data but not all the answers. Ancient man believed the world was flat. Indeed this was a logic belief which conformed with the available data, but it was of course a horribly inaccurate estimate of the shape of the Earth. 17th Century people OTOH knew the dimensions and general shape of the Earth, but still were unaware of its exact shape, considering it to be a sphere. While still not perfectly accurate their estimate is good enough that for the most part it is still used today even though we know that the Earth is in fact 0.3% oblate. Likewise NASA does not normally perform relativistic mechanical calculations for celestial navigation, 17th Century knowledge of mechanics suffices for this purpose. Clearly the knowledge of the 17th Century, while incomplete in many respects was good enough to irrefutably declare that the Earth was round, and to calculate the trajectories of the objects in the Solar System to great accuracy.
Likewise our understanding of things like basic conservation laws, causality, and thus the absolute limitations on travel to the stars. These things are not simply theories we've cooked up. They are reinforced by a vast interlocking array of observations. To for instance posit the actual existence of a reactionless drive or some form of FTL would be as if some 18th Century navigator had stumbled upon a whole new continent in the midst of the Atlantic ocean, there simply wasn't any unknown territory with the room to fit it into anymore.
Clearly you can always just say "well, you haven't looked in the right place, your viewpoint is limited by current understanding" etc. but what would you say to someone who showed you a map with Atlantis in the middle of ocean? It just can't be fitted with what we know, and we've seen too much to discount it, Atlantis just doesn't exist. It can't. FTL and etc things likewise.
So, that means we have to do it "the hard way". Will that never ever happen? I just posit that the hard way is too uneconomical to be at all common. I don't claim it is literally impossible. Contrariwise it seems likely it is possible to some degree, but I question if it can really happen enough to matter.
Well, sure, I agree, it is hard to be certain what is and isn't going to be possible in an engineering sense. You certainly cannot say with absolute certainty what the capabilities of a specific mission mass budget will be centuries down the road. There are questions though, blind optimism is not advised. First of all we have yet to witness any sort of complex nano-technology in action. While clearly it is possible to do things similar to what living organisms do IMHO there must be some fairly significant barriers to going much further than that, otherwise we'd having life forms with such capabilities already. Nor is it at all certain that such small and thus delicate and vulnerable structures could survive for long in the high radiation environment prevailing during a high velocity interstellar voyage (or even just floating around in the interstellar environment for that matter). 'starwisp' type vehicles are at best highly speculative. Possible? Maybe, but nobody has suggested a framework under which such technology would work.
I've THOUGHT about a lot things. Obviously extrapolation is reasonable, OTOH plenty of engineers and such will tell you that this level of miniaturization probably won't work. I suspect the truth is somewhere in between. Many of the things it is so easy for a sci-fi author to write up like it is plausible will turn out to be pipe dreams, but many things will turn out to be possible. The question then is will the real utility of a bunch of these low-mass craft really be great enough to do a whole lot? Only time will tell. I think the loss rate could be very high and then you're sort of back to "it takes a lot of energy" again, just for slightly different reasons. If you coupled that with "these sorts of spacecraft are pretty limited" then where are you?
Sure, never is a long time, but we also don't need to come even close to postulating never. Lets suppose it is difficult and expensive enough to travel between the stars that actual colonization is effectively a losing proposition. You might even be able to accomplish it now and then, but its not often attempted, rarely succeeds, and thus for every given instance of an inhabited planet the probability of founding even one colony is less than one. Under this assumption civilizations don't 'spread', so they will only come into contact by proximity.
Secondly we then look out at the sheer vastness of the Universe. If intelligent life isn't SUPER common, and doesn't last for millions of years, then the chances of 2 civilizations being nearby in time and space rapidly approaches zero. In the whole Universe will it never happen? Probably it will, but the chances that WE are one of that handful are very low.
I think that the fundamental stumbling block that I run into all the time with these sorts of discussions is that the human mind is simply not capable of appreciating the sheer scale of the Universe in both time and space. We see a Universe vastly full of 'stuff', but space is vast beyond all human imagining, and time is long beyond all human imagining. Unless intelligent life is either extremely common or extremely facile at both crossing these unimaginably vast reaches of space and enduring across vast cosmological ages of time then every such spark is almost sure to be unique and alone. If the Universe in its lifetime holds 10 trillion civilizations then we have virtually no hope of ever meeting even one other.
I would just say on the first point that every single organism we have ever observed, including humans, spends all the energy it can get hold of on growth and reproduction in some sense. There's NEVER 'spare' energy. Were there the vast quantities of spare energy that would be required for interstellar travel that would imply that said society has either A) limited itself in terms of growth, which IMHO implies it probably wouldn't be interested in exploration, a fundamentally growth-linked behavior; or B) is limited by some OTHER constraint.
Possibility B brings us to the second set of points you bring up. If a society was so advanced that it could do things like harness all the energy of its star, it seems hardly likely that possibility B would be a factor (IE at that level of technology you can simply synthesize matter from energy or harvest it from your star etc).
As for 'super technological wonders' like exploding stars... A) you have to posit some mechanism for this sort of thing. Its all well and good to say that is what would happen, but without either evidence or at least a theory as to how this would be done it is just a dead-end for any discussion, you might as well just say "fairies did it" or something. B) where are all these stars? Surely if a civilization can engineer entire star systems then its impact on the visible matter in the galaxy would soon be impossible to miss. Certainly if this sort of thing has happened much at all there would be whole interstellar civilizations of beings munching on stars. I can only assume one of two things is true, either this sort of thing is impossible (and indeed I cannot imagine any actual technological way to 'take apart' a star) or intelligent life is VERY rare in the Universe, rare enough that we can't pick out its signature from natural phenomena. Either of these alternatives tends to validate the original premise, that we're unlikely to ever meet another species.
Ask what question? I can ask "is some hypothetical alien civilization allocating energy to its individuals in such-and-such a way" until I'm blue in the face, there's no answer forthcoming at this time unless someone here can demonstrate that they are in contact with actual space-faring aliens... Thus we have to work from what we know. In fact I justified my assertion that no one individual would have access to excessive amounts of energy. We can debate this point of course but it wasn't the main point of the original discussion.
You can of course simply make your own assumptions, which is exactly what your points A and B ARE, simply unjustified assumptions. You would strengthen these assertions with some logical arguments as to why they are warranted. IMHO B can be dismissed. While it is likely that we will find methods of travel that are MOST energy efficient we already know the uttermost theoretical limits on minimum energy, which are actually the ones I quoted, 450 pWh/metric ton at 0.1C (and in fact this number has been demonstrated to be low by an order of magnitude). In order to achieve a lower energy cost the laws of nature must be such that the Universe as we know it could not exist. I understand that for people without a good understanding of modern physics and cosmology this sort of statement is always disputed, but its like saying after Magellan circumnavigated the globe that we could still discover that the Earth is flat, that ship has sailed, we positively know better.
As for your point A... ALL we can work with is what we know of societies ultimately. You can of course simply state "well, its alien, no argument from experience means anything" but that just means there's no discussion to be had AT ALL. I mean, fine, aliens are alien, nothing we know applies to them, we can all pack up and go home now. Instead what I've tried to do is both argue from analogy with human societies and to look at what makes human societies necessarily as they are. I've pointed out that one of the hallmarks of human society is economically rational behaviour. Humans aren't ALWAYS rational, not even at the level of entire societies, but they are pretty well bounded within limits. When a society becomes TOO economically irrational it simply cannot support itself anymore, necessary functions cease to be carried out, anomy results. Given the large investment needed to achieve even limited interstellar flight it seems reasonable that it would require some degree of stability to achieve. Economic rationality thus seems like a reasonable hypothesis, and its hard to make any sort of economic argument for interstellar flight.
As for the point that single individual (who in human society are often not rational actors) would have unfettered access to the vast energy required for an interstellar mission, the argument is similar. A society filled with irrational individuals, each one free to deploy terajoules of power as they see fit doesn't sound to me like it would last very long. Would human civilization last very long if every individual had the equivalent of an arsenal capable of sterilizing the surface of the Earth? I really doubt it. We're scared that someone might get a nuke or make a super germ. Any really advanced civilization will PERFORCE have integrated consensual decision making to a very high degree, and it will almost surely have to be quite rational.
In fact this is the real ultimate conclusion that the blogger in the original story has to come to, that advanced civilizations must be very rational, very conservative too. The alternative is what? Societies that stagger forward to advanced technology for a decade or a century and fling a few random objects out into the void before they go kaboom? If so then I think his conclusion, that we're never likely to meet them, is justified. Either way it seems justified. The likelyhood seems low IMHO. I've explained that line of reasoning, as did the original story. You're free to object, but I think the discussion won't move forward until you're willing to really examine your own assertions and weigh them against other possibilities.
Energy, or rather work, is the ultimate 'currency'. That's what you always pay for things in, or that is that's what their cost is, which you never pay less than.
Of course your star could be about to 'go kaboom' but that is going to be a once in many billions of years event for any given species, as are other such cosmic events. So we hardly need imagine it comes up often enough to matter.
The whole POINT of the debate of course is that some people can't imagine why you wouldn't do something, but lets consider some sort of analogy. Now and then human socities do something very expensive for what seems like little really logical reason. However this is extremely rare, and never rises to very high level of total society output (for instance we only expend 2% of our wealth on war today). The one single example I can even muster of a large organized social project of no explicit utility which required double digit fractions of economic output were the last few pyramids built by the Egyptians, and they only pulled of really three huge ones and about 10 other somewhat smaller examples, all within the span of a few decades. But imagine the US spending 2 TRILLION $ a year for decades on some project for which the economic return is zero and the necessity doesn't exist. It is just far-fetched.
Depends on how determined you are to go fast. A nuclear/vasimir type of design, or other advanced fission designs, could deliver constant acceleration for long periods of time with quite high specific impulse at quite useful thrust levels. You could QUITE easily get to Pluto in a year with a fairly large spacecraft. From there we can extrapolate perhaps 10 year flight times. Clearly change the aim/focus of your telescope is quite difficult, but I could see launching such a mission to study an Earth-like world around a relatively nearby system. You could in theory resolve quite a lot of detail and it would be well-worth the mission to make a close study of such a system. It may be 50 years yet before we really have deployed the relevant technology and had enough practice with it, but we could do it. If you are OK with a 40 year mission profile then nuclear propulsion isn't needed.
Ah, right, I'm unworthy to participate in your high level of erudite debate. Pfffffffft! Give me a break bozo. If you want to have a discussion it helps to be civil, but since you're not up to that...
In any case:
Its fine to ask these kinds of questions, but surely in a society which we might conceive to be something like known human ones since when does any one individual have at their disposal routinely vast quantites of energy far beyond what they need? We can point out some individuals today who are given some authority to direct the use of many resources, but they certainly aren't in absolute control. Any society which routinely put petawatts of energy in the hands of single decision makers with no obligations and constraints placed on them would not last long! If you had actually followed my entire argument you might have noted that these points have been touched on already. RATIONAL societies survive long-term, and what's rational about expending vast amounts of energy in dubiously useful ways? Our own history doesn't show much in the way of examples of this happening.
Yes, but you still fail to appreciate just what you can do with 1.316 × 10^14 kWh (and realistically of course considerably more) BESIDES accelerate 40 tons to 0.1C. 40 tons is basically an object the size of a large bus. Such an object would be a very limited probe for the cost, lacking any means of slowing down at the other end just what exactly would you hope to gain by expending a year's worth of our current power output?
There is a QUALITATIVE difference between using oil to commute 100km and traversing 50 trillion Kilometers of space in a reasonable timeframe. The cost of the former is tiny and the alternate uses of the required energy aren't particularly compelling as a result. The cost of the later is huge, equal to everything humanity today can do in a year. Even in some future with vast energy availability (and you'll quickly run into problems harvesting even a small fraction of the Sun's total output) there's no denying what that energy is capable of. Its a simple matter of trade-offs.
Sounds right. Of course I can do that math myself, but why bother? Clearly Wikipedia is a pit of inaccurate arithmetic...;)
700 AU is of course a LONG distance, but only a tiny fraction of the way to the nearest star. We could probably today without any major new tech build a probe that could reach that distance in a decade or two, maybe less. It would be a tiny fraction of the cost of even a high speed flyby probe of a nearby systems.
I got my numbers from various sources. The power requirements for 0.1 C travel came from the Wikipedia article on interstellar travel (but the math cited there appeared to be correct). The power output of the human race can also be found on Wikipedia, but is also found in IEA reports, so I would have to assume that number is at least roughly correct (I used the 2008 numbers).
In any case, I'm not sure which number you are correcting, but it sounds like you are saying the energy required to accelerate a mass to 0.1 C is 10x more than I stated. Even if its 10x easier than I stated (or we generate 10x more power today) it just means we could send 400 tons to Alpha Centauri in around 50 years vs 40 tons. Neither is even close to an adequate mass for a manned mission of such duration, though perhaps it would suffice for a flyby mission at 0.1C. I wonder if such a mission would actually learn much that we can't learn FAR cheaper by just building a huge telescope or 20. The costs are so vast it would seem like we could build an instrument to sit out at the gravitational lensing point of the Sun far more cheaply, or some other equally large scale project.
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Yeah, I'm far behind in general phone-fu, there may well be fairly simple ways to accomplish that here, it just seems like the convenience store route is not so easy. As I say, I'm far from sure it is legally mandated, VT usually has pretty lax regulations on stuff like that (no gun laws at all basically beyond "don't shoot in the direction of houses or in town!", etc). I guess you could certainly buy a phone at various box stores without a plan, they're happy to take your money. Verizon I KNOW will not activate a smart phone without a data plan though, and for that they require a contract, which means a John Hancock etc. AT&T and Sprint etc exists, and Sprint in particular is pretty lose on plans and contracts, you can definitely activate a phone without a contract and buy data service. The coverage sucks and good luck getting 3G, let alone 4G, but perhaps you can buy minutes without getting IDed. No doubt where there is sufficient will there is a way...
Well, I can't speak for other areas of the US or other countries, but in Vermont you MUST present ID to buy a pre-paid. Dunno if that's a legal requirement or what, but its universal, they record your ID before they will activate the phone. I don't doubt that if you slipped a convenience store clerk a few bills they'd scare you up a phone that wasn't linked to you, and there are plenty of homeless people wandering around with phones, etc you can probably acquire with minimal effort if you REALLY want to. Its just not as simple as paying cash.
No, they CALL the number and verify your information. That means, unless you've figured out a way to get anonymous 'burner' phone in the US that actually works, you'll be associated with the AWS account. Obviously if you're REALLY determined it IS possible to get active phones that aren't linked to you, but it isn't exactly easy and can raise the suspicion of law enforcement itself.
Of course if your goal is to provide proxy/tor services for people overseas none of this matters anyway.
They want a phone number to verify against now. You can use a prepaid card AFAIK still, but that won't help you stay anonymous...
How long would it be before all of AWS was just blocked at the national firewall level? Its not like these regimes give a crud what else they accidentally block. Most of them would as soon just block the whole thing if they could...
Actually maybe even before that, it happened incrementally. Back in the mid-60's my Father and his business partner had a consulting firm they ran out of the basement. They built all sorts of custom hardware for mostly the Air Force. He taught me basic electronics, and then when he went to work for another larger company we'd go into work on Saturday and I'd type in FORTRAN programs onto punch cards for him (but I didn't know what they did exactly). Eventually, sometime circa 1970 he was working for a place where most of what he worked on was software, and I'd play around with the PDP-11C (which had a tty). You could run BASIC and interact, so by age 7 I could use the computer like a calculator.
It wasn't until later that I really learned to seriously program. In high school we actually had A computer (TRS-80 Model 1 IIRC) which I finagled the librarian to let me play with, and I learned at least a bit. My uncle also gave us a typesetting machine that you could program in assembler using CP/M and reading the PACE assembler book I finally got the key concepts. The year after that I went to college and took FORTRAN. Hard to say in there where exactly i got to "can program" from "cannot program" but I'm sure in this day and age it would be MUCH easier and happen sooner.
Well, I KNOW there's perfectly good software available on Linux. I am pretty sure some of those things also exist on Windows, do they not?
Why would you ever need to BUY anything? I have at least 3 or 4 decent video editors that are free I can install in 5 minutes that for the level of stuff you can do with an online suite are perfectly fine. The 'article' (aka slashvertisment) is putting up a false dichotomy between pay software and a free webapp when nobody in their right mind that doesn't have at least pretensions to serious video editing has PAID for their software in a while now.
My my, and we must suppose you kiss your mother with that mouth too!
I know of no general principle which would make me conclude that message passing is safer than making system calls. In fact they offer pretty much exactly the same sorts of dangers. Much the same argument was touted by virtualization technology providers, and it hasn't proven particularly hard for exploit developers to worm their way from application to guest OS to hypervisor. I'm not at all convinced that microkernels are inherently any safer than monolithic kernels in any practical sense.
As for having more levels of privilege... There are various questions there, one being exactly what containment hierarchy is appropriate? But ultimately its the same old question all over again, how do you guarantee that the messages containing data passing between different sandboxes are benign? Why is it necessary to have a microkernel design in order to achieve this?
Finally, why in fact are you reacting as if I have badmouthed you or the concept of microkernels? I only stated that Hurd is rather obsolete at this point. Mach has been around since the 1980's and while a lot of things haven't changed THAT much its pretty clear that system architectures are evolving rapidly and are mostly held back now by software. Wouldn't it make more sense to develop an OS that was forward looking? IMHO it would draw from a wide range of experience with OSes of all types and incorporate some brand new ideas that are probably needed in order to move into the VERY many-core heterogeneous future.
Even more Finally: I don't think the answer to security issues like malware are going to be found in cleverer software designs. I think the ultimate 'solution' (and it may not look much like a solution to us) will be social and economic. Better software is clearly something we want, but its not THE solution, the bad guys will always have an almost insurmountable advantage in that realm.
Yeah, I don't know. I can't even pretend to be any more than superficially informed about modern OS design. There was a day when I worked on bare metal and RTOSes, ported FORTH to new processors and such things, but its been 25 years now. I understand that people have developed some more useful communications techniques and that a lot of the issue is CPU designs that assume a monolithic kernel architecture and aren't kind to things like microkernels. I know from casual skimming there are various areas of active research. It would seem like in the future we're likely to have dozens or 100's of cores, at which point dedicating one to running your USB port doesn't seem terribly ridiculous and I'd think that would obviate some of the context-switching issues with current designs.
Yeah, he's a bit out there, but it would be incredibly hypocritical not to give credit where due. The guy is clearly the prime mover behind a lot of free software. I'm sitting here typing this on my nice FC17 system in Firefox and using all sorts of FSF software practically every hour of the day to run my business etc. The world needs guys like RMS, even if it doesn't seem to know it or appreciate them a whole lot. In my world one RMS is worth 12 Bill Gateses.
If you're interested in understanding microkernel OS architectures, then Hurd might be useful to experiment with. Other than that its pretty close to unusuable as there isn't even basic SATA and USB support (IE you're going to have to install on OLD hardware, or much more likely in a VM where you can supply virtualized IDE).
Honestly, while I certainly don't want to rain on anyone's pet project Hurd has mostly become pointless. Its user space really offers nothing beyond what Linux or other POSIX *nix user spaces offer, and while microkernels are interesting concepts they've never proven to be terribly practical in most applications. Even in terms of microkernel design Hurd is dated. I'd think it would be much more interesting to work on future-looking OSes, say something with a Plan 9-like user space and some more modern experimental kernal with features designed around high core counts and heterogeneous compute resources. Not sure what that is, but I'm sure there are people out there working on stuff like that.
A list of patentable features of the algorithm would be right at the top of my list as well. If you can also show lack of existing patents covering any aspects of your code that would be good too.
Eh, yeah, well, we can only discuss things within the context of our own knowledge and experiences, that's true. I'm not entirely convinced that we have 'no idea' though. I think in terms of knowing what things are likely to be physically possible we're in a lot better shape than the people of 1000 years ago. I'm reminded of Isaac Asimov's famous essay where he talks about there being a HUGE difference between virtually no data and having a lot of data but not all the answers. Ancient man believed the world was flat. Indeed this was a logic belief which conformed with the available data, but it was of course a horribly inaccurate estimate of the shape of the Earth. 17th Century people OTOH knew the dimensions and general shape of the Earth, but still were unaware of its exact shape, considering it to be a sphere. While still not perfectly accurate their estimate is good enough that for the most part it is still used today even though we know that the Earth is in fact 0.3% oblate. Likewise NASA does not normally perform relativistic mechanical calculations for celestial navigation, 17th Century knowledge of mechanics suffices for this purpose. Clearly the knowledge of the 17th Century, while incomplete in many respects was good enough to irrefutably declare that the Earth was round, and to calculate the trajectories of the objects in the Solar System to great accuracy.
Likewise our understanding of things like basic conservation laws, causality, and thus the absolute limitations on travel to the stars. These things are not simply theories we've cooked up. They are reinforced by a vast interlocking array of observations. To for instance posit the actual existence of a reactionless drive or some form of FTL would be as if some 18th Century navigator had stumbled upon a whole new continent in the midst of the Atlantic ocean, there simply wasn't any unknown territory with the room to fit it into anymore.
Clearly you can always just say "well, you haven't looked in the right place, your viewpoint is limited by current understanding" etc. but what would you say to someone who showed you a map with Atlantis in the middle of ocean? It just can't be fitted with what we know, and we've seen too much to discount it, Atlantis just doesn't exist. It can't. FTL and etc things likewise.
So, that means we have to do it "the hard way". Will that never ever happen? I just posit that the hard way is too uneconomical to be at all common. I don't claim it is literally impossible. Contrariwise it seems likely it is possible to some degree, but I question if it can really happen enough to matter.
Well, sure, I agree, it is hard to be certain what is and isn't going to be possible in an engineering sense. You certainly cannot say with absolute certainty what the capabilities of a specific mission mass budget will be centuries down the road. There are questions though, blind optimism is not advised. First of all we have yet to witness any sort of complex nano-technology in action. While clearly it is possible to do things similar to what living organisms do IMHO there must be some fairly significant barriers to going much further than that, otherwise we'd having life forms with such capabilities already. Nor is it at all certain that such small and thus delicate and vulnerable structures could survive for long in the high radiation environment prevailing during a high velocity interstellar voyage (or even just floating around in the interstellar environment for that matter). 'starwisp' type vehicles are at best highly speculative. Possible? Maybe, but nobody has suggested a framework under which such technology would work.
I've THOUGHT about a lot things. Obviously extrapolation is reasonable, OTOH plenty of engineers and such will tell you that this level of miniaturization probably won't work. I suspect the truth is somewhere in between. Many of the things it is so easy for a sci-fi author to write up like it is plausible will turn out to be pipe dreams, but many things will turn out to be possible. The question then is will the real utility of a bunch of these low-mass craft really be great enough to do a whole lot? Only time will tell. I think the loss rate could be very high and then you're sort of back to "it takes a lot of energy" again, just for slightly different reasons. If you coupled that with "these sorts of spacecraft are pretty limited" then where are you?
Its an interesting question at least.
Sure, never is a long time, but we also don't need to come even close to postulating never. Lets suppose it is difficult and expensive enough to travel between the stars that actual colonization is effectively a losing proposition. You might even be able to accomplish it now and then, but its not often attempted, rarely succeeds, and thus for every given instance of an inhabited planet the probability of founding even one colony is less than one. Under this assumption civilizations don't 'spread', so they will only come into contact by proximity.
Secondly we then look out at the sheer vastness of the Universe. If intelligent life isn't SUPER common, and doesn't last for millions of years, then the chances of 2 civilizations being nearby in time and space rapidly approaches zero. In the whole Universe will it never happen? Probably it will, but the chances that WE are one of that handful are very low.
I think that the fundamental stumbling block that I run into all the time with these sorts of discussions is that the human mind is simply not capable of appreciating the sheer scale of the Universe in both time and space. We see a Universe vastly full of 'stuff', but space is vast beyond all human imagining, and time is long beyond all human imagining. Unless intelligent life is either extremely common or extremely facile at both crossing these unimaginably vast reaches of space and enduring across vast cosmological ages of time then every such spark is almost sure to be unique and alone. If the Universe in its lifetime holds 10 trillion civilizations then we have virtually no hope of ever meeting even one other.
I would just say on the first point that every single organism we have ever observed, including humans, spends all the energy it can get hold of on growth and reproduction in some sense. There's NEVER 'spare' energy. Were there the vast quantities of spare energy that would be required for interstellar travel that would imply that said society has either A) limited itself in terms of growth, which IMHO implies it probably wouldn't be interested in exploration, a fundamentally growth-linked behavior; or B) is limited by some OTHER constraint.
Possibility B brings us to the second set of points you bring up. If a society was so advanced that it could do things like harness all the energy of its star, it seems hardly likely that possibility B would be a factor (IE at that level of technology you can simply synthesize matter from energy or harvest it from your star etc).
As for 'super technological wonders' like exploding stars... A) you have to posit some mechanism for this sort of thing. Its all well and good to say that is what would happen, but without either evidence or at least a theory as to how this would be done it is just a dead-end for any discussion, you might as well just say "fairies did it" or something. B) where are all these stars? Surely if a civilization can engineer entire star systems then its impact on the visible matter in the galaxy would soon be impossible to miss. Certainly if this sort of thing has happened much at all there would be whole interstellar civilizations of beings munching on stars. I can only assume one of two things is true, either this sort of thing is impossible (and indeed I cannot imagine any actual technological way to 'take apart' a star) or intelligent life is VERY rare in the Universe, rare enough that we can't pick out its signature from natural phenomena. Either of these alternatives tends to validate the original premise, that we're unlikely to ever meet another species.
Ask what question? I can ask "is some hypothetical alien civilization allocating energy to its individuals in such-and-such a way" until I'm blue in the face, there's no answer forthcoming at this time unless someone here can demonstrate that they are in contact with actual space-faring aliens... Thus we have to work from what we know. In fact I justified my assertion that no one individual would have access to excessive amounts of energy. We can debate this point of course but it wasn't the main point of the original discussion.
You can of course simply make your own assumptions, which is exactly what your points A and B ARE, simply unjustified assumptions. You would strengthen these assertions with some logical arguments as to why they are warranted. IMHO B can be dismissed. While it is likely that we will find methods of travel that are MOST energy efficient we already know the uttermost theoretical limits on minimum energy, which are actually the ones I quoted, 450 pWh/metric ton at 0.1C (and in fact this number has been demonstrated to be low by an order of magnitude). In order to achieve a lower energy cost the laws of nature must be such that the Universe as we know it could not exist. I understand that for people without a good understanding of modern physics and cosmology this sort of statement is always disputed, but its like saying after Magellan circumnavigated the globe that we could still discover that the Earth is flat, that ship has sailed, we positively know better.
As for your point A... ALL we can work with is what we know of societies ultimately. You can of course simply state "well, its alien, no argument from experience means anything" but that just means there's no discussion to be had AT ALL. I mean, fine, aliens are alien, nothing we know applies to them, we can all pack up and go home now. Instead what I've tried to do is both argue from analogy with human societies and to look at what makes human societies necessarily as they are. I've pointed out that one of the hallmarks of human society is economically rational behaviour. Humans aren't ALWAYS rational, not even at the level of entire societies, but they are pretty well bounded within limits. When a society becomes TOO economically irrational it simply cannot support itself anymore, necessary functions cease to be carried out, anomy results. Given the large investment needed to achieve even limited interstellar flight it seems reasonable that it would require some degree of stability to achieve. Economic rationality thus seems like a reasonable hypothesis, and its hard to make any sort of economic argument for interstellar flight.
As for the point that single individual (who in human society are often not rational actors) would have unfettered access to the vast energy required for an interstellar mission, the argument is similar. A society filled with irrational individuals, each one free to deploy terajoules of power as they see fit doesn't sound to me like it would last very long. Would human civilization last very long if every individual had the equivalent of an arsenal capable of sterilizing the surface of the Earth? I really doubt it. We're scared that someone might get a nuke or make a super germ. Any really advanced civilization will PERFORCE have integrated consensual decision making to a very high degree, and it will almost surely have to be quite rational.
In fact this is the real ultimate conclusion that the blogger in the original story has to come to, that advanced civilizations must be very rational, very conservative too. The alternative is what? Societies that stagger forward to advanced technology for a decade or a century and fling a few random objects out into the void before they go kaboom? If so then I think his conclusion, that we're never likely to meet them, is justified. Either way it seems justified. The likelyhood seems low IMHO. I've explained that line of reasoning, as did the original story. You're free to object, but I think the discussion won't move forward until you're willing to really examine your own assertions and weigh them against other possibilities.
Energy, or rather work, is the ultimate 'currency'. That's what you always pay for things in, or that is that's what their cost is, which you never pay less than.
Of course your star could be about to 'go kaboom' but that is going to be a once in many billions of years event for any given species, as are other such cosmic events. So we hardly need imagine it comes up often enough to matter.
The whole POINT of the debate of course is that some people can't imagine why you wouldn't do something, but lets consider some sort of analogy. Now and then human socities do something very expensive for what seems like little really logical reason. However this is extremely rare, and never rises to very high level of total society output (for instance we only expend 2% of our wealth on war today). The one single example I can even muster of a large organized social project of no explicit utility which required double digit fractions of economic output were the last few pyramids built by the Egyptians, and they only pulled of really three huge ones and about 10 other somewhat smaller examples, all within the span of a few decades. But imagine the US spending 2 TRILLION $ a year for decades on some project for which the economic return is zero and the necessity doesn't exist. It is just far-fetched.
Depends on how determined you are to go fast. A nuclear/vasimir type of design, or other advanced fission designs, could deliver constant acceleration for long periods of time with quite high specific impulse at quite useful thrust levels. You could QUITE easily get to Pluto in a year with a fairly large spacecraft. From there we can extrapolate perhaps 10 year flight times. Clearly change the aim/focus of your telescope is quite difficult, but I could see launching such a mission to study an Earth-like world around a relatively nearby system. You could in theory resolve quite a lot of detail and it would be well-worth the mission to make a close study of such a system. It may be 50 years yet before we really have deployed the relevant technology and had enough practice with it, but we could do it. If you are OK with a 40 year mission profile then nuclear propulsion isn't needed.
Ah, right, I'm unworthy to participate in your high level of erudite debate. Pfffffffft! Give me a break bozo. If you want to have a discussion it helps to be civil, but since you're not up to that...
In any case:
Its fine to ask these kinds of questions, but surely in a society which we might conceive to be something like known human ones since when does any one individual have at their disposal routinely vast quantites of energy far beyond what they need? We can point out some individuals today who are given some authority to direct the use of many resources, but they certainly aren't in absolute control. Any society which routinely put petawatts of energy in the hands of single decision makers with no obligations and constraints placed on them would not last long! If you had actually followed my entire argument you might have noted that these points have been touched on already. RATIONAL societies survive long-term, and what's rational about expending vast amounts of energy in dubiously useful ways? Our own history doesn't show much in the way of examples of this happening.
Yes, but you still fail to appreciate just what you can do with 1.316 × 10^14 kWh (and realistically of course considerably more) BESIDES accelerate 40 tons to 0.1C. 40 tons is basically an object the size of a large bus. Such an object would be a very limited probe for the cost, lacking any means of slowing down at the other end just what exactly would you hope to gain by expending a year's worth of our current power output?
There is a QUALITATIVE difference between using oil to commute 100km and traversing 50 trillion Kilometers of space in a reasonable timeframe. The cost of the former is tiny and the alternate uses of the required energy aren't particularly compelling as a result. The cost of the later is huge, equal to everything humanity today can do in a year. Even in some future with vast energy availability (and you'll quickly run into problems harvesting even a small fraction of the Sun's total output) there's no denying what that energy is capable of. Its a simple matter of trade-offs.
Sounds right. Of course I can do that math myself, but why bother? Clearly Wikipedia is a pit of inaccurate arithmetic... ;)
700 AU is of course a LONG distance, but only a tiny fraction of the way to the nearest star. We could probably today without any major new tech build a probe that could reach that distance in a decade or two, maybe less. It would be a tiny fraction of the cost of even a high speed flyby probe of a nearby systems.
Cost?
I think people really fail to appreciate the HUGE costs involved. Energy is the ultimate currency. Its hard to see the need.
I got my numbers from various sources. The power requirements for 0.1 C travel came from the Wikipedia article on interstellar travel (but the math cited there appeared to be correct). The power output of the human race can also be found on Wikipedia, but is also found in IEA reports, so I would have to assume that number is at least roughly correct (I used the 2008 numbers).
In any case, I'm not sure which number you are correcting, but it sounds like you are saying the energy required to accelerate a mass to 0.1 C is 10x more than I stated. Even if its 10x easier than I stated (or we generate 10x more power today) it just means we could send 400 tons to Alpha Centauri in around 50 years vs 40 tons. Neither is even close to an adequate mass for a manned mission of such duration, though perhaps it would suffice for a flyby mission at 0.1C. I wonder if such a mission would actually learn much that we can't learn FAR cheaper by just building a huge telescope or 20. The costs are so vast it would seem like we could build an instrument to sit out at the gravitational lensing point of the Sun far more cheaply, or some other equally large scale project.