Slashdot Mirror

"When you want better visions -- study the visionaries" (me, though I expect others have said it...)

In that respect:
http://www.aeiveos.com/~bradbury/Authors/Engineering/Drexler-KE/index.html

The M.S. thesis (which I have read) is particularly interesting as it details concepts of nanotechnology before they may have been fully formed in Eric's mind.

three words: Matrioshka brain enshrouding. http://www.aeiveos.com:8080/~bradbury/MatrioshkaBrains/index.html

This isn't accurate, nor is it new. "Suddenly, I wondered, what if we could assemble materials like the abalone does -- but not be limited to one element?" The problem with this is that abalone isn't limited to a single element. All organisms which produce common shells are dealing with molecules of calcium carbonate (CaCO3). Many plankton produce silica shells (SiO2). Some magnetotactic bacteria produce magnetite crystals (Fe3O4). There are ~20 proteins in the human genome involved in manipulating or using selenium (Se) not to mention many more involved in dealing with iron (Fe), copper (Cu) and sulfur (S).

Life has actively used available resources (in terms of ions or molecules) for several billion years. Nor is it new that one could use biological systems to assemble nanoscale parts. That was anticipated in a paper I wrote in 2001 [1] and if one goes back in Drexler's writings the concepts were clear in papers he wrote as early as 1981 (bacteria and eukaryotic cells are nanoscale manufacturing plants -- though not general purpose nanoassemblers). Further the applications for synthetic genomes and nanoscale assembly were seen and incorporated into a business plan as early as 2002 (Robiobotics, LLC). Unfortunately, in terms of fund raising, that was about the same time as the dotcom crash and all the VC's were trying to seek out a rock to hide under.

1. Bradbury, R.J. "Protein Based Assembly of Nanoscale Parts" (2001).
http://www.aeiveos.com:8080/~bradbury/Papers/PBAoNP.html

I didn't say we should literally dematerialize it, I said we should disassemble it. There are multiple paths for doing this [1,2]. All of the planets are at the bottom of various sized gravity wells -- if you have sufficient energy to move the matter out of the well you can "quickly" disassemble the planet. If one has a significant fraction of the Sun's power available (~10^26 W) then the disassembly of Mars takes ~176 days [3]. In actual practice it is likely to take longer due to the fact that one would have to divert power from Matrioshka Brain "thought" into planetary disassembly so there is a fair amount of politics involved ("whether to think or disassemble that is the question..."). The likely path in our solar system disassembles the asteroids first and then uses the swarm resulting from that to bootstrap the disassembly of Mars and/or Mercury. I discuss this further in the chapter "Under Construction" from the collection of essays in "Year Million". In solar systems lacking an asteroid belt one would probably start with the planet closest to the star (e.g. Mercury) since it has the largest planetary solar insolation as starting energy base.

Yes, I agree that humans have pursued a lot of things just for the fun of it. On the other hand I take a fairly "moral" approach here. Humanity looses ~40+ million lives a year due to aging. If the long term choices include saving that number of lives (each year) and providing them with either multi-thousand year lifespans (in biological form) or multi-billion year lifespans (as minds uploaded into a Matrioshka Brain) vs. sending a few dozen people to drive around or build "Quonset huts" on Mars then I chose the first as a more noble goal. One can easily incorporate the "colonization" adventure into a Matrioshka Brain vision -- just survey Mars completely before you disassemble it (or as you disassemble it) and construct a simulation of it to play on/in once ones mind is uploaded (you have seen the Matrix series I presume). Or if you were addicted to playing in a "real" world reconstruct a Mars-like mini-planetoid with the leftovers from the Mars disassembly process (there is likely to be a lot of iron and oxygen left over from inner planet disassembly which isn't particularly useful from a nanotechnology standpoint). People who are choosing romantic colonization notions need to reconcile whether to dedicate intellectual and financial resources to those notions or whether they should be used to solve real problems (people lacking choices with respect to how, when and if they die). My personal preference is solving real problems.

1. Incineration, highly parallelized rail gun launches, extreme mountain building, spinning up the planet, etc. Kaku's approach to building a "Death Star" (really "Stars" if you want to disassemble the planet quickly), as seen on the Science Channel, is close -- he just doesn't realize that you can have the entire solar power output at your disposal if you have nanotechnology enabled solar power satellite construction methods.
2. http://www.stardestroyer.net/Empire/Tech/Beam/DeathStar.html
3. http://www.aeiveos.com:8080/~bradbury/MatrioshkaBrains/OSETI3/4273-32.html

There's no way of knowing whether there's an intelligent life form we've not detected yet, in this very planet. For as much as we know, Earth itself could be a "cell" of a galactic sized life form that has stars as neurons and light as nervous signals.

A long read, but very interesting one none the less. You might be more correct than you think!

http://www.aeiveos.com:8080/~bradbury/MatrioshkaBrains/MatrioshkaBrainsPaper.html

From the abstract:

A common practice encountered in literature discussing the search for extraterrestrial life is the perspective of assuming and applying human characteristics and interests to alien species. Authors limit themselves by assuming the technologies available to aliens are substantially similar or only somewhat greater than those we currently possess. These mistakes bias their conclusions, preventing us from recognizing signs of alien intelligence when we see it. They also misdirect our efforts in searching for such intelligence. We should start with the laws on which our particular universe operates and the limits they impose on us. Projections should be made to determine the rate at which intelligent civilizations, such as ours, approach the limits imposed by these laws. Using these time horizons, laws and limits, we may be better able to construct an image of what alien intelligence may be like and how we ourselves may evolve.

(Posting anon to avoid the inevitable off topic mods, though the research in the above paper being more on topic to the article than most of the posts made so far)

If you are 27, then you must have heard about Eric Drexler and Molecular Nanotechnology. Indeed Eric's master's thesis at MIT was on the subject of solar sails and Eric wrote a number of papers [1] about how MNT would enable inexpensive space access.

If you really wanted to go to space you might consider spending less time on wishful thinking and more time on constructive activities. If you were to use the existing (free) Nanoengineer-1 molecular design software to design the nanoscale parts which are elements of a nanoassembler (Nanosystems, pg 401) we would all get there much faster. Once we have a complete nanoassembler design, it can be simulated on a supercomputer to verify that it will function as described and then the race will be on to figure out how to build one [2].

Of course inexpensive access to space and molecular nanoassemblers (or disassemblers) opens up a different can-o-worms like "Which planets we should disassemble to build a Matrioshka Brain for the Kardashev Type II level civilization?" But I suppose if you are still thinking along "vacation in suborbital space" lines that you may not have gotten to that point yet.

1. http://www.aeiveos.com:8080/~bradbury/Authors/Engineering/Drexler-KE/index.html
2. It would take more space than is available here to explain what directed molecular nanoassembly enables but if you consider that DNA polymerase, RNA polymerase and the ribosome are three examples of specific molecular nanoassemblers that produce everything that is considered to be "living", you might get the general idea.

Here's a set of roadmaps generated at three-year intervals. Note that, with the exception of RAM density, each of the charted criteria outran the roadmaps' predictions.

These roadmaps are generated by a consortium of companies. They're routinely betting the future of their entire industry on these roadmaps. They're actually pretty darned conservative.

Perhaps there is an "optimum" brain....

If a brain is basically a network, then there comes a size where it's no longer efficient as a whole. And are 2 brains better than 1?

Infinite exponential growth is bullshit. There is *always* a real physical limit.

Speaking of optimal efficient brains, smaller can be better, and exponential growth hitting physical limits,
I thought you mind enjoy the following reading material:

http://www.aeiveos.com:8080/~bradbury/MatrioshkaBrains/MatrioshkaBrainsPaper.html

While some would say this is fiction (As is true for most all theoretical research, but especially so here), I've still found this paper a very interesting and entertaining read.

Quoted abstract to give you an idea:

Predictable improvements in lithographic methods foretell continued increases in computer processing power. Economic growth and engineering evolution continue to increase the size of objects which can be manufactured and power that can be controlled by humans. Neuroscience is gradually dissecting the components and functions of the structures in the brain. Advances in computer science and programming methodologies are increasingly able to emulate aspects of human intelligence. Continued progress in these areas leads to a convergence which results in megascale superintelligent thought machines. These machines, referred to as Matrioshka Brains, consume the entire power output of stars (~10^26 W), consume all of the useful construction material of a solar system (~10^26 kg), have thought capacities limited by the physics of the universe and are essentially immortal.

A common practice encountered in literature discussing the search for extraterrestrial life is the perspective of assuming and applying human characteristics and interests to alien species. Authors limit themselves by assuming the technologies available to aliens are substantially similar or only somewhat greater than those we currently possess. These mistakes bias their conclusions, preventing us from recognizing signs of alien intelligence when we see it. They also misdirect our efforts in searching for such intelligence. We should start with the laws on which our particular universe operates and the limits they impose on us. Projections should be made to determine the rate at which intelligent civilizations, such as ours, approach the limits imposed by these laws. Using these time horizons, laws and limits, we may be better able to construct an image of what alien intelligence may be like and how we ourselves may evolve.

Enjoy

I've been curious... if there was an incredibly advanced civilization that was capable of building near perfect dyson spheres around large expanses of space absorbing essentially all the radiation of the stars within it, wouldn't that look like "dark matter"?

Or perhaps even that incredibly advanced civilization consists of one or more Matrioshka Brains which are living thinking entities with very similar characteristics as Dyson spheres have, as well as answer a number of unanswered questions about cosmology (assuming they exist, which statistics say not only should exist -somewhere- in the universe, but are actually likely, and perhaps even inevitable.
Ok, that last one was my own wish more than anything else, perhaps the hopeless romantic in me, perhaps some silly child type want for such things to exist, but read the link above and decide for yourself.
It is an interesting read no matter how you take it.

To answer your question though, no I don't believe so (for either one.)
I'm fairly sure most of the people trying to prove dark matter have narrowed the list down to stuff which can't _block_ light/EM at all, just what affects energy and matter gravitationally.

A more detailed article discussing than Wikipedia that is discussing this subject can be found right here.

and go directly for a Matrioshka Brain built around the Sun. Helps against global warming too! :p

A sufficiently advanced civilization that doesn't destroy itself first will inevitably optimize their environment to the point of harvesting every last drop of energy from their star(s), such that we can't detect anything but the gravitational effects.

This mysterious "dark matter" structure is termed a Matrioshka Brain (aka: Dyson Sphere).

I understand that this theory's still a bit too shocking for many to seriously consider, so "exotic particles" - or ANY other explaination - it must surely be.

Of course if nobody has to work for a living (one of the points of the paper), one would have to wonder *why* people would seek out jobs as politicians, record or movie industry executives, etc. (I can't imagine those jobs as actually being "fun".) It is interesting to contemplate a Congress or offices in L.A. (or wherever the RIAA & MPAA hang out) which are completely empty... Now of course with so many more people with so much more free time on their hands one would imagine that there will be many more people engaged in creative activities, some of which may include producing many more records and movies. With so many more records and movies available, for artists to get "air time" they are going to have to give them away for free, or perhaps even "pay" people to listen to them. [If we assume each artist has 10 kg of nanorobots available, and one could live comfortably using less than 1 kg, one could "donate" ones nanorobot time to people who are willing to listen to, watch, or play songs, movies or games. This would be a form of virial marketing in the hope that some of the "paid" consumers would turn around and suggest to their friends that the product is decent and people should support the artists with donated nanorobot time (presumably via PayPal in nano-robot seconds or nano-robot kW rather than $ or yen).]

If you want to *worry* about something, worry about a corporation or the U.S. or perhaps China gaining enough of a micro/nanotechnology "edge" to allow things like ubiquitous surveilance & enforcement of their version of a "good" reality. Its bad enough when they try to enforce it in a state or country but they may try to extend it to the world (something that the U.S. comes dangerously close to now) or the solar system. Attempts by Sony & Microsoft to implement various forms of universal surveillance and/or control ("All your computer are belong to us") are examples of the tip of the iceberg in this area. One can only hope that with so much more free time people may become a little more educated and resist attempts to cast reality into a "there can be only one" mold.

Instead of "taking back the government" work towards making its actions irrelevant.
For example, one could support Nano@Home.

1. Sapphire Mansions (Understanding the Real Impact of Molecular Nanotechnology)
http://www.aeiveos.com:8080/~bradbury/Papers/SM.ht ml

Of course if nobody has to work for a living (one of the points of the paper), one would have to wonder *why* people would seek out jobs as politicians, record or movie industry executives, etc. (I can't imagine those jobs as actually being "fun".) It is interesting to contemplate a Congress or offices in L.A. (or wherever the RIAA & MPAA hang out) which are completely empty... Now of course with so many more people with so much more free time on their hands one would imagine that there will be many more people engaged in creative activities, some of which may include producing many more records and movies. With so many more records and movies available, for artists to get "air time" they are going to have to give them away for free, or perhaps even "pay" people to listen to them. [If we assume each artist has 10 kg of nanorobots available, and one could live comfortably using less than 1 kg, one could "donate" ones nanorobot time to people who are willing to listen to, watch, or play songs, movies or games. This would be a form of virial marketing in the hope that some of the "paid" consumers would turn around and suggest to their friends that the product is decent and people should support the artists with donated nanorobot time (presumably via PayPal in nano-robot seconds or nano-robot kW rather than $ or yen).]

If you want to *worry* about something, worry about a corporation or the U.S. or perhaps China gaining enough of a micro/nanotechnology "edge" to allow things like ubiquitous surveilance & enforcement of their version of a "good" reality. Its bad enough when they try to enforce it in a state or country but they may try to extend it to the world (something that the U.S. comes dangerously close to now) or the solar system. Attempts by Sony & Microsoft to implement various forms of universal surveillance and/or control ("All your computer are belong to us") are examples of the tip of the iceberg in this area. One can only hope that with so much more free time people may become a little more educated and resist attempts to cast reality into a "there can be only one" mold.

Instead of "taking back the government" work towards making its actions irrelevant.
For example, one could support Nano@Home.

1. Sapphire Mansions (Understanding the Real Impact of Molecular Nanotechnology)
http://www.aeiveos.com:8080/~bradbury/Papers/SM.ht ml

Lets do the math. Universe, ~13 billion years old. Earth, ~5 billion years old. Time to develop first sun-like stars perhaps 1 billion years. So there is a reasonable chance that there are (or were) Earth like planets up to 7 billion years older than Earth (at least around stars slightly smaller than the sun which age more slowly). There are some systems with younger Earths (*much* younger for those systems currently in the process of planetary formation). Lineweaver's group has worked on this and has concluded that ~70% of the Earth's in the galaxy are older than ours -- many of them by billions of years.

Based on this it is unlikely that either TPF or SETI (based on its current approaches) will discover "intelligent" life. The statistics dictate that you only have perhaps a 5000 (years) / 12,000,000,000 (years) chance (less than 1 in a million) of finding a planet which hosts "intelligent" life as we know it.

For those systems with terrestrial sized planets and those with water TPF is a reasonable effort -- it might manage to detect water and if lucky atmospheric composition that could hint at life. However pointing the SKA (or any other radiotelescopes) at the stars in the list provided are highly unlikely to be successful because they assume intelligent civilizations which are currently at (and remain at) our stage of development. (This changes the statistics to about 1 in a billion.)

The reasons for this are as follows... Whether you believe in steady state growth (Dyson's assumption in 1960), or exponential growth as "The Singularity" concept proposes the bottom line is that it seems very unlikely that a civilization would actively choose to remain at our state of development (i.e. zero growth for millions or billions of years). If you choose the steady state model the time to develop to a Dyson Shell is measured in a few hundred to a few thousand years. If you choose the singularity model then the time to develop a Matrioshka Brain (also here) is measured in decades. Once either of those states is reached the star goes "dark". So the star list is useless (to either the TPF mission or SETI) for identifying locations of intelligent civilizations with capabilities even slightly beyond our own.

Robert Bradbury

Notes:
For the above calculations I chose 5000 years as the longevity of humans with a reasonable level of technology development. One could limit it to smaller time frames (~100 years for radio or 40-50 years for lasers or rockets). TPF has a much greater chance of being successful than radio or optical SETI because it is working with a much larger time window. Water world longevities range from 100 million to many billion years if they restrict themselves to sun-like (

In any case it will not be obsolete humans which go colonizing any stars. It will be complex nanosystems which support either uploaded "natural" intelligences or artificial intelligences or a combination of the two. Ultimately the entire framework that humans tend to view life from is flawed at the levels Matrioshka Brains operate at. Rather than replicate starting almost from scratch (using gametes), advanced civilizations are more likely to divide in half (as cells do). The problem is that due to the large amount of information advanced civilizations will have at their disposal they cannot easily transmit that quantity of information across large interstellar distances. Thus replication will only take place when developed star systems happen to orbit (or be navigated) to within close proximity of undeveloped star systems. Under normal circumstances this is a very slow development process. It is possible however that from time to time that the civilizations of a galaxy might choose to use the "seed" distribution (plant) approach to development, in which case it seems likely that the galaxy would "go dark" much more quickly. That may be the case for the galaxy associated with the "naked" black hole.

A reasonable person might well consider an explanation that included the natural evolution of advanced technological civilizations before they resorted to the invention of new particles and laws of physics (as is typically a requirement as soon as you mention 'dark matter').

It is useful to keep in mind that several papers by Charley Lineweaver's group document that ~70% of the "Earth's" in our galaxy are significantly older than ours (perhaps billions of years older). It would not be that unexpected that from time to time we might encounter a galaxy where advanced civilizations had placed *all* of the reasonably available matter and energy "under management". (For the purposes of discussion we will assume that black holes do not constitute a "reasonably available" useful resource despite proposals from time to time that require rather creative physics to make them "useful".)

Why? Because the probable time to disassemble Mars is 12 hours once the asteroids have been developed into an array to harvest the entire solar power output of the sun. [1]

So any work to "develop" Mars is either (1) assuming that nanotechnology is impossible -- which seems to fly in the face of physical laws as well as much NASA funding; or perhaps (2) that it will take a very very long time to become available (which would imply the people at NASA are *not* following the Moore's Law data...; or (3) that for some romantic reasons decisions will be made to not disassemble Mars -- and this is the realm of politics and requires a mandatory behavioral enforcement dictate unlike any humanity has been able to develop or dictate over thousands of years.

I for one would like to see the carefully reasoned and thought out discussions that Mars will still exist in 30-40 years. For NASA to be funding efforts involving growing life on Mars points out how short sighted they are and how poorly they are educating the students they are educating.

Instead of enzyme studies which will be pointless -- how about some studies of more advanced methods that might be used to disassemble Mars more quickly?

1. Life at the Limits of Physical Laws

Yes, photosynthesis. In principle green plants can capture 34% of the energy in red photons and store it as chemical fuel, although in practise they normally do far worse.

From a strictly metaphysical perspective, this really is a storage of photons. The energy is stored as the Coulomb force between nuclei and electrons that gives the chemical bonds their strength. But a Coulomb force is simply the result of the rapid exchange of longitudinal photons. So I think you could legitimately look at a chemical bond as an intensely hot tiny soup of photons. The "perfect mirrors" at the end of the "cavity" are the charged particles, which absorb and re-emit the photons without loss, over and over again.

For example, I did the calculations a few days ago and it would appear current technologies allow the assembly of mammalian sized genomes *from scratch* in a few days using technologies that are available now (though the assembly of complete chromosomes needs some work it is a "methods" problem not a "technical infeasibility" problem). This doesn't violate any laws of physics. That means any complex life form can probably be assembled if you can design it. The problem is that most SciFi writers know relatively little about microbiology and biotechnology.

And *very* few SciFi writers really understand the implications of nanotechnology. I'm reasonably sure I can count them on less than 10 fingers. You don't go to the stars in "starships". You go to the stars by taking a planetary sized mind or an entire solar system. It doesn't move fast but since you've reengineered the power source (for "planets") or the sun (for solar systems) to last trillions of years who cares? Those of you who don't understand this haven't been following the /. discussions regarding the "Blinding of SciFi" or haven't read the background material on Matrioshka Brains.

Worth noting in passing is that the recent submission of astro-ph/0506110 which we hope to have published soon. Once it is completely grasped astronomers, physicists, SETI fans *AND* the Science Fiction authors will have little excuse for not seriously considering Life at the Limits of Physical Laws.

For example, I did the calculations a few days ago and it would appear current technologies allow the assembly of mammalian sized genomes *from scratch* in a few days using technologies that are available now (though the assembly of complete chromosomes needs some work it is a "methods" problem not a "technical infeasibility" problem). This doesn't violate any laws of physics. That means any complex life form can probably be assembled if you can design it. The problem is that most SciFi writers know relatively little about microbiology and biotechnology.

And *very* few SciFi writers really understand the implications of nanotechnology. I'm reasonably sure I can count them on less than 10 fingers. You don't go to the stars in "starships". You go to the stars by taking a planetary sized mind or an entire solar system. It doesn't move fast but since you've reengineered the power source (for "planets") or the sun (for solar systems) to last trillions of years who cares? Those of you who don't understand this haven't been following the /. discussions regarding the "Blinding of SciFi" or haven't read the background material on Matrioshka Brains.

Worth noting in passing is that the recent submission of astro-ph/0506110 which we hope to have published soon. Once it is completely grasped astronomers, physicists, SETI fans *AND* the Science Fiction authors will have little excuse for not seriously considering Life at the Limits of Physical Laws.

So, no, IMNSHO, I think we're much more likely to end up ripping the planets apart (oh the humanity! how unromantic!) to make better use of the matter, than wasting space & energy by living on the limited surface area of a gravity well.

A preprint discussing some of these problems is available in the preprint archive Galactic Gradients, Postbiological Evolution and the Apparent Failure of SETI.

Worth noting to the person who suggested that planets with advanced civilization migrate outward within the galaxy... The idea is on the right track but as the paper above points out -- advanced civilizations can migrate their solar systems anywhere they want. People who really want to understand galactic gradients and the probable location (and ages) of planets similar to Earth should research the papers by Charlie Lineweaver's group. Their work suggests that there are many many "Earths" in our galaxy. Many would be quite a bit older than ours if the intelligent civilizations they might have spawned chose for some illogical (nostalgic?) reason not to disassemble them.

All of this is not to say that the PicoCell or Bluetooth or other alternatives are not good ideas for airplanes for the simple reason of preventing radiotelescope interference (i.e. *real* radioastronomy rather than radioastronomy involving the questionable pursuit of ET. Of course having no-cell-phone zones (or even no-fly zones) in locations above radiotelescopes seems to be a much simpler solution. And then of course anyone who wishes to use a cell phone on a plane should be required to use a "cone of silence" (for those of you who remember "Get Smart"). :-;

A preprint discussing some of these problems is available in the preprint archive Galactic Gradients, Postbiological Evolution and the Apparent Failure of SETI.

Worth noting to the person who suggested that planets with advanced civilization migrate outward within the galaxy... The idea is on the right track but as the paper above points out -- advanced civilizations can migrate their solar systems anywhere they want. People who really want to understand galactic gradients and the probable location (and ages) of planets similar to Earth should research the papers by Charlie Lineweaver's group. Their work suggests that there are many many "Earths" in our galaxy. Many would be quite a bit older than ours if the intelligent civilizations they might have spawned chose for some illogical (nostalgic?) reason not to disassemble them.

All of this is not to say that the PicoCell or Bluetooth or other alternatives are not good ideas for airplanes for the simple reason of preventing radiotelescope interference (i.e. *real* radioastronomy rather than radioastronomy involving the questionable pursuit of ET. Of course having no-cell-phone zones (or even no-fly zones) in locations above radiotelescopes seems to be a much simpler solution. And then of course anyone who wishes to use a cell phone on a plane should be required to use a "cone of silence" (for those of you who remember "Get Smart"). :-;

> All it takes to simulate a human brain is 22.8 teraflops?
> I thought I was smarter than that.

A rough guess seems to come in at around 100 teraops or more.

In a paper by Hans Moravec, one guess is 10^14 instructions per second (Extrapolation of retina
equivalent computer operations.)

While another by Ralph Merkle, suggests 10^13 - 10^16 operations per second, based on power consumption,

and yet another by Robert McEachern suggests 10^17 FLOPS (Floating Point Operation Per Second, more comparable to computer based math and what is discussed here.)

1 x 10^12 = 1 Tera

Thusly, 10^13 = 10 T, 10^14 = 100 T, 10^15 = 1000 T or 1 P, 10^16 = 10 P, and 10^17 = 100 P (or 100,000 TeraOps)

These numbers of course all depend on the method of measurement, what is being measured, and how much bearing that particular feature matters..
Sorta as meaningless/meaningful as CPU MHZ speed goes, and likewise, comparing a computer to a brain is going to run into the same problem.

However I think its safe to say, that as long as the computers hardware works like it does and not like our brains, then it will need to simulate our hardware in software, and thus two numbers matter: 1) how fast the computer can simulate the various actions of nurons, and 2) how fast those nurons need to function to compare to a real brain. As with all forms of emulation, the host system needs to be faster than the target, usually to an order of magnatude or more...

However, they didn't really say their simulation would be running at full/live speed... Researchers can still learn alot from this even if it takes a day to process a minute or two of brain time...

Even if we were to assume 1cm^3 per neuron, that's a cube 60m on a side. If a signal needs to go from one side to the other, lightspeed is no object.

I was referring to the popular theory that the natural evolution of any intelligence that develops computational theory and spaceflight is to build a Matrioshka Brain; an MB is a series of computational shells deriving energy from thermal gradients (one side facing the sun, the other side facing interstellar space) such that the sun itself is not visible outside the system. Many claim that such a setup is inevitable as energy demands and computational needs of an interplanetary civilisation grow. The earth only gets a tiny portion of the energy that our sun outputs; when we need more than that the only way to get it is going to be space-based computational systems.

A lot of smart people now believe this is why SETI has failed to find signs of intelligent life; SETI observes visible stars, not "empty" space. Any Type-III civilisation would be "visible" only as a dim infrasun.

A good paper on MBs can be found here

To clarify:

• "You" are your emergent pattern of mind: Software.
• "You" are NOT necessarily what composes your operating substrate: Hardware.

So there may be no real barrier for "Death Stars" showing up on the door step of future worlds even in episodes VII-IX. They just got a late start in the interstellar travel queue.

Real men use phase change coolers as defined by Drexler and Henson in US Patent #4,759,404 also briefly discussed in Section 11.5 of Nanosystems . That is because the heat capacity of solids going to liquids is higher than that of liquids going to gases. Of course the engineering of a system to circulate nanoscale ice cubes within ammonia (or methanol or ethanol) and refreezing the water back into ice cubes in the "condenser" is slightly more difficult than the engineering required for heat pipes.

Real men use phase change coolers as defined by Drexler and Henson in US Patent #4,759,404 also briefly discussed in Section 11.5 of Nanosystems . That is because the heat capacity of solids going to liquids is higher than that of liquids going to gases. Of course the engineering of a system to circulate nanoscale ice cubes within ammonia (or methanol or ethanol) and refreezing the water back into ice cubes in the "condenser" is slightly more difficult than the engineering required for heat pipes.

Minimum Energy Requirements of Information Transfer and Computing

But don't suggest this to the astronomers or astrophysicists because they are so friggen sure that the universe is *dead* and nothing they observe could be explained by the activity of advanced technological civilizations... They obviously haven't read any of the work by the Lineweaver group pointing out that 75% of the stars in the galactic habitable zone are older (in some cases much older) than the Sun. [Ref: astro-ph/0401024].

Roll the open source and nanotechnology development efforts forward by a few hundred million years and project what the universe would look like...

Have the scientists concidered that maybe its just a stage 3 civilization that's getting ready to pWn us?
Maybe its just a bunch of Matrioshka brains...
Or just wussy dyson shells....

Haven't all of you terraforming advocates out there ever considered the fact that to efficiently get to Mars (I don't mean a several person space capsule -- I mean quantities of people that would be required for a "real" colony...) as well as to perform rapid terraforming (within a several hundred year lifetime) you are going to require robust molecular nanotechnology? And if you have robust molecular nanotechnology you might as well convert the entire planet into more useful forms that aren't at the bottom of a gravity well.

The world seems to be full of people who have read too much anthropocentric science fiction and don't realize that technology development is going to turn many decades old concepts that people feel all warm and fuzzy about into really silly ideas.

In the construction of Matrioshka Brains (previously discussed on /. here) one has the common choices found in software development. "Do we do it top-down or bottom-up?" Taking an existing solar system (such as ours) and disassembling the asteroids and planets and eventually shrinking the star is the top-down approach and tends to be expensive (lifting material out of large gravity wells and relocating them within solar system volumes requires a great deal of energy and time). On the other hand optimizing the development of mini-solar systems could be the bottom-up approach as one avoids the expense of large gravity wells and one can optimize the construction of "computronium" as the dust cloud and brown dwarf evolve. One could imagine an advanced civilization structuring things such that they feed material into the brown dwarf such that they keep it just on the edge of becoming a star. Under ideal circumstances a civilization would like an energy source which produces the greatest amount of light (or IR) energy with the minimal amount of UV energy (which can break atomic bonds and is ultimately wasteful).

If the only criteria the astronomers are using for their conclusions is an excess of IR radiation then they don't really have much of a basis for their proposal other than the bias that such observations must fit the perspective of "natural" objects rather than "engineered" objects.

Oh yes, and before you cast me as a troll, as someone did last week, read the friggen papers.

As another reader pointed out there is a serious drool factor in a dual core AMD Opteron. Other than the gamers and overclockers one does not need dual cores or multi-GHz clock speeds for most applications. My desktop system is a dual processor 200MHz Pentium Pro system (circa '97) and my web server which was /.'ed in August is a dual processor 100 MHz Pentium (circa '95). "Dual" processors is *not* new. Both systems work fine for the jobs they need to perform most of the time. The only times they don't is when clueless programmers overengineer their web sites. I guess it takes a lot more than dual cores or GHz clock speeds to make me drool. :-;

But getting back to the topic at hand. Most of my dual processor systems *rarely* use both processors. I think I've only noticed one program (a commercial OCR program) that seems to be programmed to take advantage of dual processors). I think the older versions of Netscape may have an explicit problem with dual processors if Javascript is enabled. [I suspect this is because Javascript may try to run as a separate thread and both Javascript and the HTML image display code use the memory heap at the same time without single threading the code and end up corrupting the heap. But this is just a guess on my part.]

The real reason for going to multiple cores is (a) the drool factor; and (b) competitive edge [for example Sun is pushing on 4 & 8 cores to distinguish themselves from the commodity processors]; and (c) true supercomputer applications. With respect to (c) a lot of people in government and research were pretty upset with the fact that the U.S. didn't have the #1 spot in the Top500 list for the better part of 2 years. While having multiple cores helps put you back at the top of the list -- supercomputer architectures are complex. You reduce the processor delays between the processors on the same chip but for problems which require the CPU and memory of thousands of processors (protein folding for example) you still have "speed-of-light" message passing delays between the multi-core processors. That requires a very sophisticated message passing network. [See theoretical discussion here.] You can reduce these delays by packing the processors closer together but then you have heat and reliability problems.

These problems aren't quite as significant with server farms because the data is coming from and going out into the world and interprocessor delays are not as important as they are in supercomputers and large database applications that have to be concerned with concurrency issues.

It is interesting to note that IBM is running the Blue Gene clock speeds at rates significantly below what AMD and Intel chips are at and even IBM's PPC chips are capable of. And this is from the company that used to build ECL based mainframes that had to be water cooled (so they know the technology). I presume this is because the want to keep the heat production down, reliability up and perhaps to minimize the excess space (and therefore interprocessor delays) that water cooling might require.

Additionally, it might turn out that the speed of light is a hardlimit (no warp?!) and the most intelligent course of action is to disassemble all the planets in your solar system to build an efficient matrioshka brain around your star to live virtually ever after.

--

Electromagnetic rail looks promising for real orbit possibility: http://www.aeiveos.com/~bradbury/MatrioshkaBrains/ MassDrivers.html

You may need better than a 128 bit file system for your Matrioshka Brain, but even that's not sure.

And your 640k quote is dubious. Here's a real quote that you can wow the punters with instead:

"There is no reason for any individual to have a computer in their home." - Ken Olsen, President of Digital, 1977.

Mike

What happens when we take over this galaxy? Will we let all that energy go flying out into space? How long before we start encasing stars in solar panels?

You might be interested to read about the Matrioshka Brain idea, which is a variation of the Dyson Shell in that the shell itself is the new thinking and living substrate ("matrix") for a post-biological civilization.

Maybe the SETI people should start looking for the disappearance of stars and/or galaxies.

Matrioshka Brains would be dark, and amazingly efficient (emitting some infrared), so the best way to detect them would be to observe that the rotational rate of a galaxy doesn't match the observed solar mass... hey... wait... that's supposed to be exotic Dark Matter, not hidden stars! :-)

--

--

Ahhh...all the dark matter is probably composed of Matrioshka Brains ;)

Here is my 'sci-fi' grant proposal. I hope you approve:

1. Wait for advanced nanotechnology and brain-scanning tech to emerge over the next 25 years. I'll still need funding during this period to analyze the research landscape for suitable bla bla (i.e. sit on my ass.)
2. Launch a 'seed' probe using the old space elevator.
3. Have the seed probe attach to any unclaimed, suitably-sized asteroid and self-assemble the solar arrays, dish, and computing substrate necessary for a couple million transhuman beings + "matrix" environment.
4. "Broadcast" the willing scanned human minds from Earth for $0/lb (and let the bio-luddites join the dinosaurs.)
5. Grow our new home into a dyson-sphere-sized Matrioshka Brain around the Sun to add to the "missing [thinking] matter" out there. :)
6. No profit.

So if that's a goal of ours, perhaps it's a goal of another race's. And perhaps they got a head start on us, and that large percentage of "dark matter" actually consists of Dyson Spheres which capture everything, so are "undetectable" by us. That's pretty scary, to think that we just lost that much playground, and will eventually have to deal with the bully--on his own terms perhaps.

I mentioned this a year ago or so, and someone pointed me in the direction of Matrioshka Brains, so I will include some links for that as well. And an excellent discussion.

I would add to the last part that the larger planets could be taken apart by space elevators as well. They'd just start with the upper atmosphere; then work their way down. All the time the mass is getting smaller, and the elevators are pulling mass out so they can make themselves bigger in order to reach deeper. I think it's workable, and appears to be the most efficient way to do it--get the mass all out into "orbit" first. Actually, when you're about halfway done you can then start shipping what you mine off to other locations, and taking that amount of mass out of the elevators as well since they won't need to counterbalance as the planet's now smaller. (I don't know what the mathematical "middle point" where you start dismantling the elevators actually is--it could be something other than 50%.)

We could have "planet splitter seeds" which we shoot off to other stars, and they start with a tiny, correctly-placed elevator and build more of them as fast as is physically possible; the seed would be smart enough to calculate all the masses and start with the most effective one that would lead to the earliest date at which the entire mass of the star system is being used for computation.

The only problem is if we encounter life. Will our machines just assimilate it? Are the ones out there programmed to preserve us? Have they already done so?

So if that's a goal of ours, perhaps it's a goal of another race's. And perhaps they got a head start on us, and that large percentage of "dark matter" actually consists of Dyson Spheres which capture everything, so are "undetectable" by us. That's pretty scary, to think that we just lost that much playground, and will eventually have to deal with the bully--on his own terms perhaps.

I mentioned this a year ago or so, and someone pointed me in the direction of Matrioshka Brains, so I will include some links for that as well. And an excellent discussion.

I would add to the last part that the larger planets could be taken apart by space elevators as well. They'd just start with the upper atmosphere; then work their way down. All the time the mass is getting smaller, and the elevators are pulling mass out so they can make themselves bigger in order to reach deeper. I think it's workable, and appears to be the most efficient way to do it--get the mass all out into "orbit" first. Actually, when you're about halfway done you can then start shipping what you mine off to other locations, and taking that amount of mass out of the elevators as well since they won't need to counterbalance as the planet's now smaller. (I don't know what the mathematical "middle point" where you start dismantling the elevators actually is--it could be something other than 50%.)

We could have "planet splitter seeds" which we shoot off to other stars, and they start with a tiny, correctly-placed elevator and build more of them as fast as is physically possible; the seed would be smart enough to calculate all the masses and start with the most effective one that would lead to the earliest date at which the entire mass of the star system is being used for computation.

The only problem is if we encounter life. Will our machines just assimilate it? Are the ones out there programmed to preserve us? Have they already done so?

One reason for this is if it takes you 3 or 5 billion years to get all the information back from many light years away there may be a significant possibility that you or the message transports will be exposed to a Gamma Ray Burst that wipes a significant fraction memory. The second reason is that you can't have a significant "conversation" across millions of light years -- the chances are significant that you will have computed the answer yourself by the time you send a probe a million light years away and get a response back from some colonized system. Finally we have know for the last ~25 years (since the Project Daedalus study that you can't send probes out, matter based messages back, etc. at anything close to the speed of light. The energy released when you strike a piece of space dust or even particles from interstellar solar winds is going to erode the ship. Proj. Daedalus solved this by building a big shield on the front of the ship. But if you do that you are going to need a lot more energy to accelerate ships or message transports to higher velocities. Many of these problems are discussed in the Matrioshka Brain papers.

I would suggest that Krauss & Starkman may be very good physicsts & astronomers but I would think twice about putting them on an engineering project.

Robert

Robert