Re: entropy and sustainability
So there maybe physical limits on certain technologies, but are there limits on human creativity in creating new technologies? We may fill the capacity of a silicon chip, but what about a chip made of something organic? or some other yet unthought of way to store info? Certain ideas may have finite limits, but is the number of idea finite? Jason
Re: entropy and sustainability
So there maybe physical limits on certain technologies, but are there limits on human creativity in creating new technologies? We may fill the capacity of a silicon chip, but what about a chip made of something organic? or some other yet unthought of way to store info? Certain ideas may have finite limits, but is the number of idea finite? Jason There are ultimate physical limits on the speed of data processing, but I don't see why there are any limits on computer programs, and thus no limit to software technology, even given hardware constraints. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/
Re: entropy and sustainability
There are ultimate physical limits on the speed of data processing, Are there? I mean, there are limits on how fast silicon can go, but are there real limits on how fast /any/ material can go? but I don't see why there are any limits on computer programs, and thus no limit to software technology, even given hardware constraints. Actually, there are hard limits on certain software technologies, same as for hardware. Comparison-based sorting can't use less than O(n log(n)) comparisons, for example. Of course, there are other algorithms that may or may not be faster in your particular case, but specific technologies do possess hard limits. Jon Cast CS Student
Re: entropy and sustainability
Fred Foldvary wrote There are ultimate physical limits on the speed of data processing, Jon Cast wrote: Are there? I mean, there are limits on how fast silicon can go, but are there real limits on how fast /any/ material can go? Divide the diameter of a neutron by the speed of light: you probably can't make a gate flip in less time than that. but I don't see why there are any limits on computer programs, and thus no limit to software technology, even given hardware constraints. Actually, there are hard limits on certain software technologies, same as for hardware. Comparison-based sorting can't use less than O(n log(n)) comparisons, for example. [...] Quantum computing will break some of the rules, but it won't remove all limits. -- Anton Sherwood, http://www.ogre.nu/
Re: entropy and sustainability
--- Wei Dai [EMAIL PROTECTED] wrote: Economic activity can't increase indefinitely, because eventually we'll have improved our technologies to the limits imposed by physics Fred Foldvary wrote: I don't see why physics limits all technological progress. For example, someone could write improved software, and that would have nothing to do with physical limitations. Engineering improvements can also be made within current knowledge of physics. ... There are physical limits on the speed and energy-efficiency of processors and on the capacity of data storage, and thus on the complexity and efficiency of software. Such limits have not yet been approached, of course, but they're not infinitely far away. The Tipler time-machine, if memory serves, is an example of a device that ought to work if it could be built, but cannot be built because the forces involved are (necessarily) great enough to break any possible material. -- Anton Sherwood, http://www.ogre.nu/
Re: entropy and sustainability
--- Wei Dai [EMAIL PROTECTED] wrote: Economic activity can't increase indefinitely, because eventually we'll have improved our technologies to the limits imposed by physics I don't see why physics limits all technological progress. For example, someone could write improved software, and that would have nothing to do with physical limitations. Engineering improvements can also be made within current knowledge of physics. Similar propositions apply to biological knowledge. New genetic combinations can be invented within the current knowledge of basic biology. Generally, it seems to me that applications of a science can advance even if the science does not. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/
Re: entropy and sustainability
John Perich wrote: . . . here's a thought: in six billion years, the sun will burn out, making all research into sustainability and environmental / resource economics a waste of time. . . . Not a complete waste; the study will be useful toward setting up ecosystems elsewhere. -- Anton Sherwood, http://www.ogre.nu/
RE: entropy and sustainability
JP wrote: Actually, no, here's a thought: in six billion years, the sun will burn out, making all research into stainability and environmental / resource economics a waste of time. There's an obvious connection to entropy right there. -JP As long as environmental and resource economics take a direct influence on economic policy, productivity and welfare like other economic research you could your thought give an extension: ...making all research in economics a waste of time. Probably you don't know, but the connection of entropy and economy is still, obviously without relevance, a common concept in so called ecological economics, a field of research with huge influence in environmental policy, especially in Germany. Because I don't agree with that, I'm looking for profound arguments against that costly influence. Your comment is right, but for my audience probably not convincing. Steffen -Original Message- From: John Perich [mailto:[EMAIL PROTECTED]] Sent: Monday, April 08, 2002 6:04 PM To: [EMAIL PROTECTED] Subject: Re: entropy and sustainability Well, Fred beat me to the punch here on the smart-aleck response. Unless you mean entropy as something other than the standard accepted definition - namely, a decrease in ordered energy on a thermodynamic level - then we can't help you. Actually, no, here's a thought: in six billion years, the sun will burn out, making all research into sustainability and environmental / resource economics a waste of time. There's an obvious connection to entropy right there. -JP From: Fred Foldvary [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: entropy and sustainability Date: Mon, 8 Apr 2002 08:10:59 -0700 (PDT) Dear armchairs, who among you knows something new about the consequence of entropy on sustainability and environmental/ressource economics (books, papers, etc.)? Steffen I know something: any article on economics with the word entropy is likely to be nonsense, unless it itself declares such articles nonsense. Entropy says a closed system will dissipate into unavailable energy. But the earth is not a closed system. It keeps getting solar energy, and therefore the biomass and economic activity can increase indefinitely, so long as the sun continues to shine. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/ -- I'm never gonna work another day in my life. The gods told me to relax; they said I'm gonna be fixed up right. I'm never gonna work another day in my life. I'm way too busy powertrippin', but I'm gonna shed you some light. - Monster Magnet, Powertrip _ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.
RE: entropy and sustainability
Because I don't agree with that, I'm looking for profound arguments against that costly influence. From Jean Bricmont's essay Science of Chaos or Chaos in Science in _The Flight From Science and Reason_, ed. Paul Gross, et al: As discussed in Penrose [R. Penrose, 'The Emperor's New Mind' and 'On the Second Law of Thermodynamics'], the earth does not gain energy from the sun (that energy is reradiated by the earth), but low entropy; the sun sends (relatively) few high-energy photons, and the earth reradiates more low-energy photons (in such a way that the total energy is concerved). Expressed in terms of 'phase space,' the numerous low-energy photons occupy a much bigger volume than the incoming high-energy ones. So the solar system, as a whole, moves towards a larger part of its phase space while the sun burns its fuel. Nice, but is there a meaningful amount to cover all human uses? I turn to The Skeptical Environmentalist by Bjorn Lomborg (though, since environmentalists have equated him with holocoust sympathizers, you will want to go to his source material and avoid using his name), and look at figure 73 on page 133 (in the chapter on energy). It shows, inter alia, total annual [human] energy consumption (400EJ), total plant photosynthesis (1,260EJ), and ANNUAL solar radiation (2,895,000EJ). Taking that surplus of solar energy (2,895,000 - 1,260) and asking a physcist or chemist to interpret that surplus in terms of entropy (if that's possible or even meaningful), I think you will be able to show that there is plenty of low entropy out there for human consumption for a long time to come. Also, though not directly related, if you seek discussions of entropy in lay-man's terms, you might try turning to the creationist/evolution debate in the States. Creationists love to claim that evolution violates entropy, so scientists have spent alot of time explaining entropy in simple terms. You could try www.infidels.org and go to their library section, also www.talkorigins.org has pages somewhere in their site that discuss entropy. Good luck! jsh __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/
Re: entropy and sustainability
On Mon, Apr 08, 2002 at 08:10:59AM -0700, Fred Foldvary wrote: Entropy says a closed system will dissipate into unavailable energy. Entropy applies to open systems too. The way it works is, a given energy source (the sun) and heat sink (outer space) allows you to remove so many bits of entropy per second from your system, so that limits your activities to producing no more than that many bits of entropy per second. But the earth is not a closed system. It keeps getting solar energy, and therefore the biomass and economic activity can increase indefinitely, so long as the sun continues to shine. Economic activity can't increase indefinitely, because eventually we'll have improved our technologies to the limits imposed by physics, and used up every square inch of sunlight. At that point thermodynamics will determine the ultimate limit on the rate of economic activity on Earth. On Tue, Apr 09, 2002 at 11:35:31AM +0200, Hentrich, Steffen wrote: Probably you don't know, but the connection of entropy and economy is still, obviously without relevance, a common concept in so called ecological economics, a field of research with huge influence in environmental policy, especially in Germany. Because I don't agree with that, I'm looking for profound arguments against that costly influence. Your comment is right, but for my audience probably not convincing. Can you cite a paper from this literature? Without knowing more it's hard to tell if the concept of entropy is being used correctly or not.
Re: entropy and sustainability
Dear armchairs, who among you knows something new about the consequence of entropy on sustainability and environmental/ressource economics (books, papers, etc.)? Steffen I know something: any article on economics with the word entropy is likely to be nonsense, unless it itself declares such articles nonsense. Entropy says a closed system will dissipate into unavailable energy. But the earth is not a closed system. It keeps getting solar energy, and therefore the biomass and economic activity can increase indefinitely, so long as the sun continues to shine. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/
Re: entropy and sustainability
Well, Fred beat me to the punch here on the smart-aleck response. Unless you mean entropy as something other than the standard accepted definition - namely, a decrease in ordered energy on a thermodynamic level - then we can't help you. Actually, no, here's a thought: in six billion years, the sun will burn out, making all research into sustainability and environmental / resource economics a waste of time. There's an obvious connection to entropy right there. -JP From: Fred Foldvary [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: entropy and sustainability Date: Mon, 8 Apr 2002 08:10:59 -0700 (PDT) Dear armchairs, who among you knows something new about the consequence of entropy on sustainability and environmental/ressource economics (books, papers, etc.)? Steffen I know something: any article on economics with the word entropy is likely to be nonsense, unless it itself declares such articles nonsense. Entropy says a closed system will dissipate into unavailable energy. But the earth is not a closed system. It keeps getting solar energy, and therefore the biomass and economic activity can increase indefinitely, so long as the sun continues to shine. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/ -- I'm never gonna work another day in my life. The gods told me to relax; they said I'm gonna be fixed up right. I'm never gonna work another day in my life. I'm way too busy powertrippin', but I'm gonna shed you some light. - Monster Magnet, Powertrip _ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.
Re: entropy and sustainability
Do you mean this even when entropy is used in the context of information theory? Gustavo No, Claude Shannon's http://cm.bell-labs.com/cm/ms/what/shannonday/paper.html usage, to separate noise from information, regards statistical entropy, a measure of dispersion, a different meaning from theormodynamic entropy, which was the environmental question. From http://www.csu.edu.au/ci/vol03/finalst3/node3.html#SECTION0003 The entropy is a property of a distribution over a discrete set of symbols. It is strongly sensitive to the number or variety of the symbols and less so to their relative probabilities of occurrence. The entropy of the sequence has a number of equivalent interpretations. It is a measure of the complexity of the random process that generates the sequence. It is the length of shortest binary description of the states of the random variable that generates the sequence, so it is the size of the most compressed description of the sequence. It is the number of binary questions that need to be asked (20 questions style) to determine the sequence. It also measures the average surprise, or information gain, occasioned by the receipt of a symbol. In other words, the entropy measures the complexity or variety of the random variable that underlies a process. Fred Foldvary = [EMAIL PROTECTED] __ Do You Yahoo!? Yahoo! Tax Center - online filing with TurboTax http://taxes.yahoo.com/
