16. October 2009 by admin.

With the speed of computers so regularly seeing dramatic increases in their processing speed, it seems that it shouldn’t be too long before the machines become infinitely fast — except they can’t. Physicists have now shown that computers have a speed limit as unbreakable as the speed of light. If processors continue to accelerate as they have in the past, we’ll hit the wall of faster processing in less than a century.

Intel co-founder Gordon Moore predicted 40 years ago that manufacturers could double computing speed every two years or so by cramming ever-tinier transistors on a chip. His prediction became known as Moore’s Law, and it has held true throughout the evolution of computers
– the fastest processor today beats out a ten-year-old competitor by a factor of about 30.

If components are to continue shrinking, physicists must eventually code bits of information onto ever smaller particles. Smaller means faster in the microelectronic world, but physicists at Boston University in Massachusetts, have slapped a speed limit on computing, no matter how small the components get.

 No system can overcome that limit. It doesn’t depend on the physical nature of the system or how it’s implemented, what algorithm you use for computation or any choice of hardware and software.

There is an equation for the minimum sliver of time it takes for an elementary operation to occur. This establishes the speed limit for all possible computers, and that is, calculating that, for every unit of energy, a perfect quantum computer spits out ten quadrillion more operations each second than today’s fastest processors.

The physicists pointed out that technological barriers might slow down Moore’s law as we approach this limit. Quantum computers, unlike electrical ones, can’t handle “noise” — a kink in a wire or a change in temperature can cause havoc. Overcoming this weakness to make quantum computing a reality will take time and more research.

As computer components are packed tighter and tighter together, the newer processors are getting hotter sooner than they are getting faster.  Hence the recent trend in duo and quad-core processing; rather than build faster processors, manufacturers place them in tandem to keep the heat levels tolerable while computing speeds shoot up. Scientists who need to churn through vast numbers of calculations might one day turn to superconducting computers cooled to drastically frigid temperatures. But even with these clever tactics there’s no getting past the fundamental speed limit.

From a theorist’s perspective, it’s probably good to know that fundamental limits are there, sort of an absolute ceiling. Perhaps it’s disappointing that infinitely fast computers can’t be built, but when a theory of physics allows for infinitely fast computation, there could be a problem with that theory.

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1. October 2009 by admin.

The financial crisis is the result of our living beyond our financial means. The climate crisis is a result of our living beyond our planet’s means.    

Economists are now on the verge of tearing their hair out, because the links between finance and climate are not always obvious, because of the way the economy is accounted. Nature, our most fundamental capital asset, does not appear on the balance sheet. Nor does its depreciation.

The world needs a new accounting system, one that measures rainforest loss as asset depletion rather than, as now, simply as income, and similarly, the world needs to start making the emitters of carbon into the air pay a proper price for the damage they are doing. Greenhouse gas emissions are damaging ecosystems on which most economic activity, including agriculture, ultimately depends.
 

The droughts that triggered the sharp rises in food price in 2007 and early 2008 were most likely due to climate change. The UN’s Intergovernmental Panel on Climate Change reckons that climate change is likely to cut global food production by 20 to 40% by 2100.

As stated in a recent report by the Australian Association for the Study of Peak Oil, energy security is another critical link between natural resources and economic systems.  The world is pumping up three times more oil than is being discovered, and that simply can’t go on. Diminishing reserves are driving the volatility in energy prices. As other resources become scarce, they too will underline world financial and economic stability.

Feeding the world will require twice as much food by mid-century. But most of the remaining viable land is forested. Clearing those trees will drive up greenhouse gas emissions, destabilising ecosystems and accelerating climate change, so further diminishing the productivity of the land.

A key moment when the planet might be saved will be April 2nd, 2010 in London, when the new grouping of nations known as the G20 will hold a summit. It must tackle climate change as well as the financial crisis.

Meanwhile here in the U.S., the main argument against climate action is not the claim that global warming is a myth. It is, instead, the argument that doing anything to limit global warming would destroy our economy. It’s important, then, to understand that claims of immense economic damage from climate legislation are as bogus, in their own way, as climate-change denial. Saving the planet won’t come free (although the early stages of conservation actually might). But it won’t cost all that much either.

First, the evidence suggests that we’re wasting a lot of energy right now. That is, we’re burning large amounts of coal, oil and gas in ways that don’t actually enhance our standard of living — a phenomenon known in the research literature as the “energy-efficiency gap.” The existence of this gap suggests that policies promoting energy conservation could, up to a point, actually make consumers richer.

Second, the best available economic analyses suggest that even deep cuts in greenhouse gas emissions would impose only modest costs on the average family. Earlier this month, the Congressional Budget Office released an analysis of the effects of Waxman-Markey, concluding that in 2020 the bill would cost the average family only $160 a year, or 0.2 percent of income. That’s roughly the cost of a postage stamp a day.

By 2050, when the emissions limit would be much tighter, the burden would rise to 1.2 percent of income. But the budget office also predicts that real G.D.P. will be about two-and-a-half times larger in 2050 than it is today, so that G.D.P. per person will rise by about 80 percent. The cost of climate protection would barely make a dent in that growth. And all of this, of course, ignores the benefits of limiting global warming.

The campaign against saving the planet rests mainly on lies.

Recently a very popular national radio talk show host informed his audience of a “buried” Obama administration study showing that Waxman-Markey would actually cost the average family $1,787 per year. Needless to say, no such study exists, and similarly false claims about the cost of Waxman-Markey have been circulated by many supposed experts.

We’ve already seen in the health care debate, the polarization of our political discourse has forced self-proclaimed “centrists” to choose sides — and many of them have apparently decided that partisan opposition to President Obama trumps any concerns about intellectual honesty.

The claim that climate legislation will kill the economy deserves the same disdain as the claim that global warming is a hoax. The truth about the economics of climate change is that it’s relatively easy being green.

JA

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