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rainer_d:
Well, in a way, this problem will solve itself, over time. The fossile energy-resources will be used up very quickly.

At present usage rates, the U.S. has 800 years of coal left. China's coal supply dwarfs the U.S.'s. Oil can be produced from resources not yet tapped such as oil fields with a higher cost of extraction, oil shale, tar sands, and the aforementioned 800 years of coal -- so dwindling conventional reserves are a non-issue.

and here in Germany, it is expensive already, thanks to "Green" government.
Thanks to Green government, Germany's green nuclear power program is being decomissioned.

dhart:
Energy efficiency is environmentally friendly...

Energy efficiency is not intrinsically environmentally friendly. There is no shortage of clean energy that can be exploited in the form of nuclear fission power. California saves lots of energy by not using nuclear power to desalinate (make into fresh water) sea water. California alternatively drains Mono Lake and diverts water from the Colorado River and the San Joaquin Delta.

Spending money to reduce energy consumption tends to hurt the environment by interfering with environmentally friendly factors such as economic and technological growth. It's a waste of engineering resources that could be put to positive environmental use -- such as devising cheaper and better nuclear power plants.

Church and Turing never said anything about computers in general. They made claims about variations of logical computing machines (LCMs) with computation defined as anything that can be described by "rules of thumb". Now, depending on your definitions of: "rules of thumb", data, program, machine, and computer... you are making wildly different claims about computation.

Church and Turing NEVER endorsed what you said, that "The Church-Turing principle only claims that there is no computer that can solve more problems than a Turing Machine. "

If you don't believe me, then read Church and Turings original papers on the subject, or check this discussion of the myths surrounding the Church-Turing thesis.

This incorrect interpretation that you have of the Church-Turing thesis discourages interest in alternative forms of computing.

These simplifications made LISP into a way of describing computable functions much neater than the Turing machines or the general recursive definitions used in recursive function theory. The fact that Turing machines constitute an awkward programming language doesn't much bother recursive function theorists, because they almost never have any reason to write particular recursive definitions, since the theory concerns recursive functions in general. They often have reason to prove that recursive functions with specific properties exist, but this can be done by an informal argument without having to write them down explicitly. In the early days of computing, some people developed programming languages based on Turing machines; perhaps it seemed more scientific. Anyway, I decided to write a paper describing LISP both as a programming language and as a formalism for doing recursive function theory. The paper was Recursive functions of symbolic expressions and their computation by machine, part I (McCarthy 1960). Part II was never written but was intended to contain applications to computing with algebraic expressions. The paper had no influence on recursive function theorists, because it didn't address the questions that interested them.

It's called Turing's World, and it was written by John Barwise and John Etchemendy, philosophers at Stanford.

I never could have done the homework for my computability and logic class without it. Debugging turing machines on paper is a bitch!
--

More ironic that AI people need a book to defend their own field. Go check out McCarthy's book Defending AI Research: A Collection of Essays and Reviews .

I have wondered the same thing, and wrote an essay about how this might turn out.

Incidentally, here's a PC World article about a device that can "paint" color images directly onto your retina.

Here is the intro:

The future of the Internet is in what I call "rational programming" derived from a revival of Bertrand Russell's Relation Arithmetic. Rational programming is a classically applicable branch of relation arithmetic's sub theory of quantum software (as opposed to the hardware-oriented technology of quantum computing). By classically applicable I mean it is applies to conventional computing systems -- not just quantum information systems. Rational programming will subsume what Tim Berners Lee calls the semantic web. The basic problem Tim (and just about everyone back through Bertrand Russell) fails to perceive is that logic is irrational. John McCarthy's signature line says it all about this kind of approach: "He who refuses to do arithmetic is doomed to talk nonsense."

And finally, China

Is anyone else thinking about the movie Virus? Or is this the super army or robots anime has been warning us about for years. Maybe we should start considering the status of our own army of super robots. Some of the people I could find working on it are The Georgia Tech Mobile Robot Laboratory, The MIT Mobot Group, The University of Texas at Austin has a Robotics Research Group, and there is the Stanford Robotics Laboratory. All in all pretty dismal. you only have to go a few links down in a search result list to get to the Biped Robot Research in the World link. If you check it out you may notice, They are all in Japan. We are soooo gonna get our asses kicked. Even Robodex 2000, the world's first exhibition of "Robots as Partner" from November 24-26 is in Yokohama, Japan.

One of the topics on Slashdot that seems to generate the most ill-informed opinions is copyright law.

Here is a clue: Every objection or complaint that Slashdot readers have posted on this site was anticipated by the authors of the Constitution some 200+ years ago. These guys were REAL thinkers. These ideas have been tested time and again in both the courts and in commerce. Statutes governing Copyrights have been continually refined and updated to ensure fairness to both the author and end user.

If you want to see the careful balance in the law, READ the Constitution and the
case law that has come in front of the Supreme Court.

One of the interesting things that went on at SC2000 was Netchallenge competition with cash prizes.

Its winners have all shown something of interest to the public (disclaimer: our application is one of them, so I am not a neutral party).

Our demo included, we think, the first ever demonstration of interdomain operation of DiffServ-based IP QoS (more on this to come on the QBone web site) as well as an interesting application developed by Computer Music Center folks from Stanford. The application (audio teleportation) allows one to be teleported into a space with different acoustics (with CD-quality sound). During SC2000, two musicians gave a live performance from two different places with their sound being mixed in the air in the acoustics of a marble hall in Stanford.

Pixar has improved their shadow algorithms greatly since "Geri's Game". Based on a new method presented at SIGGRAPH 2000, hair can be self-shadowed in a more efficient manner while producing a higher quality result. Categorized under the Image Based Representations paper section, Deep Shadow Maps (PDF available) will greatly enhance modelled hair, fur or smoke. I've heard that this new algorithm has already been encorporated into Renderman and I believe was even used in Toy Story 2. Who needs clothes when you can cover every character in fur or hair? :^)

Why is the Higgs so important?

Apart from being the last of the Standard Model particles to be discovered, it is also (via the so-called) Higgs Mechanism responsible for the generation of mass.

Well, just as the photon is the "carrier" of the electromagnetic field, the carrier (incidently, all such carrier particles are bosons - that is, have integer "spin") of the mass field is the Higgs Boson, and will be seen as evidence for either the Standard Model of Particle Physics, or (depending upon its properties, or indeed, existence!) for other competing models. As one might well imagine, the mass generation process is very interesting to Physicists, and Higgs discovery would certainly be worthy of a Nobel prize.

As to the closure of LEP - LEP has done some startling physics and has been an extremely successful endevour however you look at it (for a start, without CERN we would not have the World Wide Web!) The collaborative model of smaller states coming together to afford large scientific projects was the predessesor to the ISS, and even a couple of the US High Energy Physics experiments (such as the experiment I'm involved with, BaBar are going the same route.

Finally, don't forget that Physics is still a human endevour, and us Physicists need a pat on the back sometimes too!

- Dan

PS: Ed, get back to work!

It HAS happened before in the US, though only in local elections. Most of them seem to be mistakes, but one can never tell. see here
--

Does the term "Flipped SU(5)" mean anything to you?

Suggest you check out Hagelin's scientific background a bit more before you start suggesting that Hagelin isn't a "real" Quantum Physicist. It is easier to say than "theoretical physicist" or "Quantum Field Theorist," afterall. A good place to start would be Hagelin's scientific publications.

You might be interested to know that his former Physics professor at Harvard, Howard Georgi, says that "He's not a kook. He's an incredibly smart guy who has well-thought-out opinions on many things." As you can see, Professor Georgi isn't a kook, a pseudo-scientist, or an intellectual slouch, either.

Not only was the Book of World Records a spinoff from the brewery, but so was Student's t distribution. (I shit you not.)

On a side note, I was about to link to Eric's Treasure Trove of Mathematics but it seems that CRC has shut them down.

That really really sucks, much more a trademark dispute over some stupid domain name. Content is where it's at.

They got started with the Bochs software Kevin wrote and let them have for free.

Kevin Lawton occasionally makes this insinuation, though even he isn't cracked enough to make the claim outright. Bochs is an emulator, VMware is a virtual machine monitor. Different technology, people. As Kevin Lawton has been discovering for the last year and a half or so, Bochs doesn't help you make something like VMware.

VMware was founded by Mendel Rosenblum of Stanford, and was an outgrowth of his Disco/SimOS research projects. Read some of the papers here for some of the research that made VMware possible. Notice that none of it has anything to do with emulation.

I'm not sure who holds the copyrights on this stuff, though; the ability to publish on line might be a part of the agreement when you have one of these journals publish your stuff, or they might just do it anyway and nobody complains because it's so useful.

-Erf C.

__________________________________________

According to Knuth, the correct term is email. And I for one don't feel comfortable disagreeing with Knuth. :-)

I write "email" instead of "e-mail". Why? Because Don Knuth (CS stud) says so!
--

-- Donald E. Knuth (from here)

There is another project, Gravity Probe B, that is planning to launch a satellite. The project is trying to measure the effect of the Earth on the space-time fabric, something different than gravity waves.

It sounds a lot like what my old lab at Stanford was doing, in their 3-D fax project, except using ice rather than a more permanent material.

yamutt said,
...it's the code-morphing abilities of
the chip. This chip has the ability to emulate any processor that TransMeta puts its mind to emulate.

That is true...as long as the processor T$ wants to emulate is an x86. According to Professor Vaghan Pratt of Standford University, the Crusoe series is only capable of emulating the x86 processor architecture as it's wired into the chips.

This Paper explains Stuart Cheshire's latency lessons from Bolo.

I think the key difference between Cheshire's bolo and the apple ][ game is that Cheshire wrote it around the network code from the start (on an Acorn BBC Micro computer, wow!)

From the FAQ (second question):

Who "owns" the results? What will happen to them?
Unlike other distributed computing projects, Folding@home is run by an academic institution (specifically the Pande Group, at Stanford University's Chemistry Department), which is a non-profit institution dedicated to science research and education. The results from Folding@home will be made available on several levels. First, we put movies and images of all folding runs on the web for everyone to see...

If I draw a sketch of a painting, does the original artist own my sketch, too?

Yes. If you create a work of art which is primarily a reproduction or representation of a copyrighted work, and release it commercially, it is a copyright violation. The best example I am aware of is the Rock and Roll Hall of Fame posters. Someone took a photo of the Rock Hall in Cleveland, OH, made a poster of it, and distributed it commercially. I.M. Pei, the architect, successfully sued.

The limit is "fair use" which covers such things as reviews and satire. You can read more about fair use on Stanford's site at http://fairuse.stanford.edu/

Bob

The last I heard, current Uranium reserves will supposedly last well over 100 years at the current burn rate.

Very true... at the current burn rate. But that's not what was being discussed, now was it? I'm talking about REPLACING our existing fossil fuel sources with nuclear power. Uranium is a limited resource just like fossile fuels, and thus doing this doesn't solve the problem anyway!

I'm sorry, but your information is not correct. There is enough nuclear fuel around to last us for thousands of years, easily. Where are you getting your estimates from? Here's a page from John McCarthy's Sustainability of Human Progress FAQ:

-=-=-
How long will nuclear energy last? These facts come from an articleBernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

-=-=-

The last I heard, current Uranium reserves will supposedly last well over 100 years at the current burn rate.

Very true... at the current burn rate. But that's not what was being discussed, now was it? I'm talking about REPLACING our existing fossil fuel sources with nuclear power. Uranium is a limited resource just like fossile fuels, and thus doing this doesn't solve the problem anyway!

I'm sorry, but your information is not correct. There is enough nuclear fuel around to last us for thousands of years, easily. Where are you getting your estimates from? Here's a page from John McCarthy's Sustainability of Human Progress FAQ:

-=-=-
How long will nuclear energy last? These facts come from an articleBernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

-=-=-

The last I heard, current Uranium reserves will supposedly last well over 100 years at the current burn rate.

Very true... at the current burn rate. But that's not what was being discussed, now was it? I'm talking about REPLACING our existing fossil fuel sources with nuclear power. Uranium is a limited resource just like fossile fuels, and thus doing this doesn't solve the problem anyway!

I'm sorry, but your information is not correct. There is enough nuclear fuel around to last us for thousands of years, easily. Where are you getting your estimates from? Here's a page from John McCarthy's Sustainability of Human Progress FAQ:

-=-=-
How long will nuclear energy last? These facts come from an articleBernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

-=-=-

The fact that what I tell you is the accepted standard wisdom within the nuclear power industry doesn't make it false. If you want accurate information about how nuclear power works, eventually you'll have to listen to people who know something about it rather than just listening to people who are terrified by it.

Sorry. I not only don't buy that nuclear power is as safe or safer than other forms, but you haven't addressed the primary point I've made, which is that nuclear power as it exists today cannot possibly supply the world's energy needs... it can only delay the inevitable by a few years.

That's a reasonable question. How long will nuclear power last us? You seem to think it will only last "a few" years. What assumptions are you making to get that figure? And by "few" do you mean a thousand years, a hundred years, a dozen years?

Another nuclear advocate, John McCarthy, has an FAQ on nuclear energy as part of his sustainability website; I recommend it to you. His sources calculate that with breeder reactors we could make known supplies of nuclear fuel last for a fair bit more than "a few" years using known technology. Here are some details from this page:

-=-=-
How long will nuclear energy last? These facts come from an article& lt;/A> by Bernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

-=-=-

The fact that what I tell you is the accepted standard wisdom within the nuclear power industry doesn't make it false. If you want accurate information about how nuclear power works, eventually you'll have to listen to people who know something about it rather than just listening to people who are terrified by it.

Sorry. I not only don't buy that nuclear power is as safe or safer than other forms, but you haven't addressed the primary point I've made, which is that nuclear power as it exists today cannot possibly supply the world's energy needs... it can only delay the inevitable by a few years.

That's a reasonable question. How long will nuclear power last us? You seem to think it will only last "a few" years. What assumptions are you making to get that figure? And by "few" do you mean a thousand years, a hundred years, a dozen years?

Another nuclear advocate, John McCarthy, has an FAQ on nuclear energy as part of his sustainability website; I recommend it to you. His sources calculate that with breeder reactors we could make known supplies of nuclear fuel last for a fair bit more than "a few" years using known technology. Here are some details from this page:

-=-=-
How long will nuclear energy last? These facts come from an article& lt;/A> by Bernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

-=-=-

The fact that what I tell you is the accepted standard wisdom within the nuclear power industry doesn't make it false. If you want accurate information about how nuclear power works, eventually you'll have to listen to people who know something about it rather than just listening to people who are terrified by it.

Sorry. I not only don't buy that nuclear power is as safe or safer than other forms, but you haven't addressed the primary point I've made, which is that nuclear power as it exists today cannot possibly supply the world's energy needs... it can only delay the inevitable by a few years.

That's a reasonable question. How long will nuclear power last us? You seem to think it will only last "a few" years. What assumptions are you making to get that figure? And by "few" do you mean a thousand years, a hundred years, a dozen years?

Another nuclear advocate, John McCarthy, has an FAQ on nuclear energy as part of his sustainability website; I recommend it to you. His sources calculate that with breeder reactors we could make known supplies of nuclear fuel last for a fair bit more than "a few" years using known technology. Here are some details from this page:

-=-=-
How long will nuclear energy last? These facts come from an article& lt;/A> by Bernard Cohen.

Nuclear energy, assuming breeder reactors, will last for several billion years, i.e. as long as the sun is in a state to support life on earth.

Here are the basic facts.

1. In 1983, uranium cost $40 per pound. The known uranium reserves at that price would suffice for light water reactors for a few tens of years. Since then more rich uranium deposits have been discovered including a very big one in Canada. At $40 per pound, uranium contributes about 0.2 cents per kwh to the cost of electricity. (Electricity retails between 5 cents and 10 cents per kwh in the U.S.)

2. Breeder reactors use uranium more than 100 times as efficiently as the current light water reactors. Hence much more expensive uranium can be used. At $1,000 per pound, uranium would contribute only 0.03 cents per kwh, i.e. less than one percent of the cost of electricity. At that price, the fuel cost would correspond to gasoline priced at half a cent per gallon.

3. How much uranium is available at $1,000 per pound?

   There is plenty in the Conway granites of New England and in shales in Tennessee, but Cohen decided to concentrate on uranium extracted from seawater - presumably in order to keep the calculations simple and certain. Cohen (see the references in his article) considers it certain that uranium can be extracted from seawater at less than $1000 per pound and considers $200-400 per pound the best estimate.

   In terms of fuel cost per million BTU, he gives (uranium at $400 per pound 1.1 cents , coal $1.25, OPEC oil $5.70, natural gas $3-4.)

4. How much uranium is there in seawater?

   Seawater contains 3.3x10^(-9) (3.3 parts per billion) of uranium, so the 1.4x10^18 tonne of seawater contains 4.6x10^9 tonne of uranium. All the world's electricity usage, 650GWe could therefore be supplied by the uranium in seawater for 7 million years.

5. However, rivers bring more uranium into the sea all the time, in fact 3.2x10^4 tonne per year.

6. Cohen calculates that we could take 16,000 tonne per year of uranium from seawater, which would supply 25 times the world's present electricity usage and twice the world's present total energy consumption. He argues that given the geological cycles of erosion, subduction and uplift, the supply would last for 5 billion years with a withdrawal rate of 6,500 tonne per year. The crust contains 6.5x10^13 tonne of uranium.
7. He comments that lasting 5 billion years, i.e. longer than the sun will support life on earth, should cause uranium to be considered a renewable resource.

Comments:

• Cohen neglects decay of the uranium. Since uranium has a half-life of 4.46 billion years, about half will have decayed by his postulated 5 billion years.
• He didn't mention thorium, also usable in breeders. There is 4 times as much in the earth's crust as there is uranium.
• He did mention fusion, but remarks that it hasn't been developed yet. He has certainly provided us plenty of time to develop it.

The main point to be derived from Cohen's article is that energy is not a problem even in the very long run. In particular, energy intensive solutions to other human problems are entirely acceptable.

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BG turned his back on the very same institution on which Lessig relies for his livelihood.

Actually Lessig taught last year in Berlin, and moved to Stanford Law School this year. Mr. Gates in fact has given a lot of money to build and equip a new computer building at Harvard, not far from where the first computer at Harvard was built, and not far from the debate. The Berkman Center where Lessig worked and his own office had a number of Microsoft Windows Intel computers when I visited, although Lessig himself seems to be naturally a Macintosh type. I don't believe Lessig has any bias against Bill Gates or Microsoft--he teaches students the law as best he can, and his brief to advise Judge Jackson was a model of impartiality.

Lessig has publicly stated that he thinks the *government* should be involved in making software

Read his book, "Code and Other Laws of Cyberspace," and you will learn what he really thinks. He thinks there is a place for laws with technology such as the Internet, for example to protect the public domain and give incentives for new works to be created. He refers to Jefferson--who if he was a "liberal" in your sense was nevertheless a radical one.

And Lessig is doing a lot more than that old story about being master in the Microsoft case. He is leading a lawsuit to overturn the Copyright Term Extension Act, Eldred v Reno. The trouble is that Jack Valenti considers that law already bought and paid for, and didn't respond to that suit during the debate--instead, preferring to talk about Napster and other cases in which the difference is not that clear between Lessig and Valenti.

I think the debate was productive. It gave Valenti a chance to enter the lion's den and talk about copyright policy with some smart people, some of whom may go to work for him. The side representing Free Software should be as bold and persuasive. But it's hard unless the comments stick to the point and unless they refrain from confusing personality and appearance with real views and understanding.

But you don't necessarily have to believe me--he's my lawyer, and doing a fine job, I say. For further information about Larry Lessig, see his Stanford web page and his older Berkman Center page, where you can read many of his works online and comment on them.

The hyperlink streaming video (realplayer req.)

In this video, Doug Engelbart demonstrates cross references, which he even calls hyper links. Goodbye patent!

Check out http://foldingathome.stanford.edu/ and help them write a Linux version of the client.

That's not prior art. That's stretching an existing circumstance to try to relate it to a new 'invention'.

No, the original poster is completely right, that a patent has to be (in theory) non-obvious to someone "learned in the art".

e.g. see http://otl.stanford.edu/inventors /pa tents.html

Next on the block: Itanium. Doesn't go fast enough, and needs an optimizing compiler with the mind of God to make it go.

Went to the Stanford EE380 talk last week. The head architect of AMD's 64-bit architecture spoke. No details on implementation, just the architecture as visible to the programmer. It's the obvious extension of x86 to 64 bits, no more, no less. In 64-bit mode, there are more registers and no segmentation. Bootable as a 32-bit CPU, can be run in its native 64-bit mode, or can run 32-bit programs under a 64-bit OS. Still supports all the 16-bit modes. The GCC port took about a month. That's the probable future.

More specifically Real Video Demonstration of Hyperlinking.

Sorry to veer off topic, but does anybody know where I could find more information on the chord key set used in clip 3? There are some other images of it on the site, but I haven't been able to find an explanation of how it worked. Was it a total keyboard replacement or more like a macro input device?

Hi,
Just check the clip N.7 on Stanford and decide for yourselves.
Quite amusing, isn't it? It looks like... mmm... something called... Internet?
Come on, you BT guys. If you want to be rich, work. A lot. But do not pretend to own something taht is not yours.

Kinda sed some words twice and added a few characters at the end of the URL there (what of "Use Preview Button!" don't people get?)

http://sloan.stanford.edu/Mous eSi te/1968Demo.html

This is better

> I hope they come out with a version that can work without the screensaver.

yea, you're not alone and we do have one (for linux and windows): check out the Folding@home site and go to the download page, sign up, and then download.

> I hope they come out with a version that can work without the screensaver.

yea, you're not alone and we do have one (for linux and windows): check out the Folding@home site and go to the download page, sign up, and then download.

Looks cool. Is it open source? I'm concerned that clients like SETI (and this) could just be an NSA setup to have the public decrypt its own communications on the government's behalf.

From their site:

Why no Mac/Solaris/etc version?

We're looking for good programmers to help with the ports to Mac, Solaris, etc. In general, the Cosm libraries should be easy to port and thus (with some help), we should be able to whip out these versions. Interested in volunteering? Please email help@folding.stanford.edu.

Presumably if you volunteer to port to system x they'll have to let you see the source code. They might even let you see it if you ask nicely for all I know.

As for SETI, I don't know if their code is available at all (I think not --at least officially); but I know they do not want any unofficial versions around and that they've even refused assistance to produce versions optimized for the 3DNow extensions in AMD chips (none exist now AFAIK).

Looks cool. Is it open source? I'm concerned that clients like SETI (and this) could just be an NSA setup to have the public decrypt its own communications on the government's behalf.

From their site:

Why no Mac/Solaris/etc version?

We're looking for good programmers to help with the ports to Mac, Solaris, etc. In general, the Cosm libraries should be easy to port and thus (with some help), we should be able to whip out these versions. Interested in volunteering? Please email help@folding.stanford.edu.

Presumably if you volunteer to port to system x they'll have to let you see the source code. They might even let you see it if you ask nicely for all I know.

As for SETI, I don't know if their code is available at all (I think not --at least officially); but I know they do not want any unofficial versions around and that they've even refused assistance to produce versions optimized for the 3DNow extensions in AMD chips (none exist now AFAIK).