Slashdot Mirror

Unfortunately it hasn't been updated for some years, but it's a good starting point for someone looking to put together a more complete bibliography.

TWIS is a somewhat entertaining college radio show that is podcast. Not the most thorough of science reporting, but digestable & there is some good stuff. Berkeley Groks is in the same vein, but far nerdier.

The Naked Scientists:
http://www.thenakedscientists.com/

Berkeley Groks Science
http://www.ocf.berkeley.edu/~clgroks/

ScienceCast:
http://sciencecast.net/

Personally, I can't get into indie podcasts due to the typically poor production values. There are a lot of insightful podcasters that could be developing a real audience if they would just buy a high quality mic.

The adage that security is the opposite of usability is false, of course. The problem is that people aren't very good at making intelligent design decisions when faced with both sets of requirements.

There is a great paper on this subject by Ka-Ping Yee here (PDF link).

Are you insane? Not only was there prior art, there is documented evidence that Doyle knew about it before filing for his patent. See here for a start.

The problem with that is that in languages such as C++ and Java inheritance is the only convenient mechanism of code reuse (and things are made even worse by the fact that it doubles as a contract-enforcing mechanism in C++). If you introduce mixins or other similar concept, the need for MI largely goes away - see Ruby and Sather as two good examples (at the same time, it might be said that you still have MI, only done in such a way as to highlight its code-reusing purpose). Sather is, in my opinion, the language which got it right: strict separation between classes and interfaces; you can implement an interface, and an interface can extend another, but you can never inherit from a class (but you can 'include' it into yours). Take a look at it, it's a very interesting approach.

Talkorigins is quite open that it exists to debunk the lies and distortions of creationists by pointing out the misunderstandings of the science involved. The fact is that speciation has been observed both in the wild and in the lab. For example lab experiments involving fruitflies (a favourite of scientists because of its short reproductive cycle) have shown that when subjected to different food supplies for an extended period that flies were 'speciated', ie. they didn't repoduce with members of the other group even when together http://evolution.berkeley.edu/evosite/evo101/VC1fE videnceSpeciation.shtml.
Some examples from outside the lab:
http://www.pbs.org/wgbh/evolution/library/05/2/l_0 52_05.html
http://www.actionbioscience.org/evolution/irwin.ht ml
http://www.talkorigins.org/faqs/comdesc/section1.h tml#morphological_intermediates_ex3

Anyway this whole macroevolution as seperate from microevolution (where one's provable and one's supposedly not) is an invention of creationists. Macroevolution relies on the exact same processes as microevolution, the only requirement is some (usually environmental) factor to create seperate breeding groups of a species. http://www.talkorigins.org/indexcc/CB/CB902.html

You can remain in your blissful ignorance by convincing yourself that evolution is a religion and that it cannot be observed for all I care. Just don't try and force your beliefs on other people by arguing for it not to be taught in a science classroom, where it belongs.

Sadly, the "space bending" (lensing) that you're talking about is different than the theoretical model I'm talking about.

OK, I see what you're getting at - how do we know we're not living on a torus or a trumpet or something? You're right that we can't measure these things directly - however, as the linked article shows, we can make some fairly strong deductions based on things like the distribution of cosmic radiation. The fact that our instruments are in the universe isn't really an issue, in the same way that living on the surface of the Earth doesn't mean you can't show it's round (just look at the horizon).

You're right that there are parts of cosmology that currently can't be tested or examined in any meaningful way. In these cases, you're also right that the theories are not scientific and, as such, I would not expect them to be taught to kids in science class. When we've figured out a number of tests that could prove the theories wrong, then we can start teaching them in science classes.

An aside: To my knowledge no one knows what causes gravitational lensing

No, gravitational lensing is pretty thoroughly understood - it's a direct consequence of General Relativity. The dark matter thing you're talking about is an attempt to test the existence or otherwise of MACHOs - weakly interacting massive particles - that, if passed in front of a star, tend to make it glow more brightly for a brief period by lensing the light towards us. That is an untested theory, but it's still scientific as the testing is happening pretty much as we speak. In a few years the predictions of the theory will either be refuted or confirmed. If the latter, we can then start looking for new tests of the theory. By contrast, no-one has even figured out how to develop a test for ID (that I know of - correct me if I'm wrong).

The point, I think, with Kansas is that the schools shouldn't discount the -possibility- of intelligent design.

Oh, I completely agree. They still shouldn't be teaching a nonscientific theory in a science class though.

I don't know exactly to what extent ID is covered in the science classes of Kansas, but surely we're not so insecure about the foundations of our science that we don't think it can hold up to a teacher saying "...and there may be a God involved"?

Very few people are insecure about the foundations of science, but many are justifiably concerned over the fact that about 3/4 of Americans think that one of science's most powerful, best tested theories is complete bollocks. We don't want to give these people any more rope with which to hang themselves (unless we're really really keen on Darwinian evolution :-P)

Plus, it sets a very bad precedent. What happens when the flat-earthers start demanding equal time in geography classes in an attempt to "teach the controversy"? And don't get me started on those "intelligent falling" nutters ;-)

Who the FUCK said SETI was science, so I can beat their ass?

SETI itself?. A quote from their webpage: "SETI@home is a scientific experiment that uses Internet-connected computers in the Search for Extraterrestrial Intelligence (SETI)." They also provide convenient links under a "SCIENCE" heading.

SETI is not science. SETI is looking for evidence. SETI is the stage you get before you have science.

SETI is looking for evidence to support the theory (based partly on evolution and partly on the size of the universe) that life exists elsewhere.

I'm not aware of any fossil evidence showing half-way mutated species. If someone knows of some, could they provide a link to a reputable website detailing this evidence?

Transitional forms are consistent with the idea of evolution. But I hesitate to call it a theory. It doesn't deserve to be. Evolution is a hypothesis that is consistent with lots (tons!) of observations. I say this because evolution still has no mathematical formulation. It has no predictive power. Compare it to well formulated physical theories like Classical Dynamics, Quantum Mechanics, or even softer theories like Marshall's Supply and Demand. They are not easily assailed by muzzy thinking. But Biologists have been easy on themselves for over 150 years! They have not developed deep mathematical understanding of the forces control evolution. They are still waving their arms. What is their response when attacked? The attackers are simpletons, visigoths, fanatics. No further discussion required! Not an impressive defense of a profound idea. When biologists develop the the rich mathematical foundations of evolution, which surely exist, the debate with creationists will end.

This is a silly game - for every intermedite form produced you'll simply shoehorn it into one category of the other and say "but what is between those?". The world's supply of discoverable fossil's is very much finite, while you can keep splitting hairs indefinitely.

In practice Archeopteryx is between lizards and birds. Between lizards and Archeopteryx are therapod dinosaurs. Between early lizard like therapods and Archeopteryx are late more bird-like dromaeosaurids and between early dromaeosaurids like Troodons and Archeopteryx are various feathered dinosaurs, which includes fossils that simply had feathers, apparently for warmth, through to later fossils that actually had clearly flight adapted feathers.

Want to try something different? How about whale evolution? We can start with a land dwelling mammal that looked fairly dog like but had certain ear structures not found in other mammals that are more suitable for hearing underwater. Then there's ambulocetus which was similar, but in practice was rather akin to a mammalian crocodile, with back legs obviously adpated for swimming, the same ear structures as our first creature, and a nose structure, similar to a crocodile, that was ideal for breathing while immersed in shallow water. Next there are things like rodhocetus which is remarkably whale like, yet still posses back legs, and still has a nasal structure placng the nostrils toward the tip as in ambulocetus. There's aetiocetus which shows the transition from snout tip nostrils toward nostils at the top of the skulls as in modern whales. Then there's basilosaurus which is decidedly whale like, but lacking in a few modern whale features, and retaining distinct, but quite useless, hind limbs similar to those of rodhocetus.

You can find similar sets of forms for the development of horses, the development of snakes from lizards, and even for the ape to man path, among many others.

Oh, I'm sure you can parse those and say "but what's between that?", but I think for most people who are not being mindlessly dogmatic that represents fairly reasonable evidence of transitions from lizards to birds, or from land dwelling mammals to whales, an, if they bothered to do the extra research and reading, the development of horses, snakes and man.

Jedidiah.

Mashooka and Yeh Dil are movies that no one in India has heard of. Saathiya was a great movie in its original Tamil version made by one of India's greatest directors Mani Rathnam, but I'm not sure how good the remake was. I suggest that you get your Indian movies from Netflix where you can see the user ratings - In a country that produces a gazillion movies, the average movie is sure to suck. You need to get movie recommendations from Indians rather than watching movies like 'Yeh Dil'

For starters, use this.

What you want is Scatter/Gather, a procedure defined in a scientific paper about 15 years ago. This is a clustering . If it hasnt been implemented yet to industrial scale, its probably because the computing requirements of a system like that are unmanageable.

The reason you may get negative comments, may be because of your own ignorance, and not the ignorance of the Slashdot audience.

For plenty of information on evolution: http://evolution.berkeley.edu/
For examples of transitional forms in the fossil record:
http://evolution.berkeley.edu/evosite/lines/IAtran sitional.shtml
The truth of the matter is that evolution has evidence from nearly every discipline of science: anthropology, biology, physics, psychology, and chemistry. The theories themselves are now finding uses in electrical engineering and computer science.

How does life begin from a a few elements?
http://www.chem.duke.edu/~jds/cruise_chem/Exobiolo gy/miller.html While the atmospheric conditions that precipitated this result is now in question, this is just an example of how science continually re-evaluates itself. The theory of gravity is far more in a state of flux than evolution, but I'm pretty sure that I'd be in pain if I jumped from my balcony.
Once you have amino acids, it isn't that big of stretch to have autocatalytic RNA. (Self-replicating single stranded DNA)

Law of Entropy? I assume you mean the second law of thermodynamics, which pertains only to closed systems. My body will also tend toward a state of disorder when I die, but I fail to see your point. Energy has been transferred from our sun to the earth in the form of light and heat. This very energy enables me to type my message. This same energy is what makes life possible on our planet. Contrary to what most people think, there is no law of entropy that states order must always decrease. http://www.infidels.org/library/modern/richard_car rier/entropy.html

Law of conservation of mass negates the big bang? Perhaps you're familiar with Einstein's equation (E=MC^2)? Energy is proportionate to mass; thus mass can become energy or energy can become mass. Law of Conservation of Mass-Energy has displaced the law of conservation of mass. If this weren't true, I'd expect an interesting explanation for the atom bomb. Perhaps the creator just wills electric to come from nuclear power plants.

While you mention 'scientific laws of today', you quote old scientific thoughts from hundreds of years ago and laymen notions of modern laws. What laws of today to you speak?

The truth is CREATIONISM is a theory of last resort for those clinging to antiquated ways of thinking. And while I try respect spirituality, leave it in your church. At one time, I believed that I should respect everyone's choice of religion; as politics once again becomes interwoven with religion I realize I have to become more active in debate. Take some time to study molecular biology, physics, and logic; and come up with an interesting argument. I'm curious as to how you would explain the 'evolution' of HIV and antibiotic resistance.

The reason you may get negative comments, may be because of your own ignorance, and not the ignorance of the Slashdot audience.

For plenty of information on evolution: http://evolution.berkeley.edu/
For examples of transitional forms in the fossil record:
http://evolution.berkeley.edu/evosite/lines/IAtran sitional.shtml
The truth of the matter is that evolution has evidence from nearly every discipline of science: anthropology, biology, physics, psychology, and chemistry. The theories themselves are now finding uses in electrical engineering and computer science.

How does life begin from a a few elements?
http://www.chem.duke.edu/~jds/cruise_chem/Exobiolo gy/miller.html While the atmospheric conditions that precipitated this result is now in question, this is just an example of how science continually re-evaluates itself. The theory of gravity is far more in a state of flux than evolution, but I'm pretty sure that I'd be in pain if I jumped from my balcony.
Once you have amino acids, it isn't that big of stretch to have autocatalytic RNA. (Self-replicating single stranded DNA)

Law of Entropy? I assume you mean the second law of thermodynamics, which pertains only to closed systems. My body will also tend toward a state of disorder when I die, but I fail to see your point. Energy has been transferred from our sun to the earth in the form of light and heat. This very energy enables me to type my message. This same energy is what makes life possible on our planet. Contrary to what most people think, there is no law of entropy that states order must always decrease. http://www.infidels.org/library/modern/richard_car rier/entropy.html

Law of conservation of mass negates the big bang? Perhaps you're familiar with Einstein's equation (E=MC^2)? Energy is proportionate to mass; thus mass can become energy or energy can become mass. Law of Conservation of Mass-Energy has displaced the law of conservation of mass. If this weren't true, I'd expect an interesting explanation for the atom bomb. Perhaps the creator just wills electric to come from nuclear power plants.

While you mention 'scientific laws of today', you quote old scientific thoughts from hundreds of years ago and laymen notions of modern laws. What laws of today to you speak?

The truth is CREATIONISM is a theory of last resort for those clinging to antiquated ways of thinking. And while I try respect spirituality, leave it in your church. At one time, I believed that I should respect everyone's choice of religion; as politics once again becomes interwoven with religion I realize I have to become more active in debate. Take some time to study molecular biology, physics, and logic; and come up with an interesting argument. I'm curious as to how you would explain the 'evolution' of HIV and antibiotic resistance.

There are plenty of European/Western scientists, that most would consider some of the greatest scientists in the world, believed in a Christian view of God

This is very true. Take Charlie Townes, the nobel laureate who invented the maser and essentially also the laser. He also recently won the 2005 Templeton Prize for Progress Toward Research or Discoveries about Spiritual Realities (it's worth about $1.5 million).

Here's an interview with Professor Townes that discusses religion and intelligent design.

Maybe the SunGrid would be better used to raise their SETI@Home stats...

http://oceanstore.cs.berkeley.edu/
At least, they have pond.

There was a press release from U.C. Berkeley in 2000 (also discussed on Slashdot) that discussed a finding about a particular kind of algea that, when a key nutrient was withheld, produced hydrogen instead of oxygen. This is a conversion of solar energy into hydrogen that is certainly much more efficient than using electrolysis. The problem, as usual, is converting a laboratory observation into a viable commercial production method (assuming that it's viable at all and not just some side effect).

If hydrogen is to become viable for personal transportation, it will need to get past the need to use petrochemicals. I am optimistic that this will one day happen, but hopefully not before we've exhausted most of our oil resources. It would sure be nice to slow down consumption and save that for other uses.

I didn't see an answer posted yet. I must not have looked hard enough, I suppose. I don't think it's that hard, although I did solve a similar puzzle years ago from William Wu, which means I had already gone through this kind of process (http://www.ocf.berkeley.edu/~wwu/riddles/medium.s html).

It's a cool puzzle, and the steps you have to go through to figure it out are fun to find. The meataphysical implications of the statement kicking off the process, even though everyone knew the statement to be true before it was said, is by far the most interesting part.

On the 100th night, all blue eyed people leave the island.

there are lots of sub 4000 day solutions on the forum at the berkeley site, for example this one takes 3473 days:

http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB .cgi?board=riddles_hard;action=display;num=1027805 293;start=393#393

Fascinating! It's so good, I'm even a little bit proud I solved it after some hard thinking. At least I'm very sure that I solved it ;).

This
http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#1000wires
and this
http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#sinkTheSub

were also two I quite enjoyed.

Fascinating! It's so good, I'm even a little bit proud I solved it after some hard thinking. At least I'm very sure that I solved it ;).

This
http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#1000wires
and this
http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#sinkTheSub

were also two I quite enjoyed.

let me first reword the problem to the way I think of it. Let us think of all the prisoner having "tokens" that they are passing around via the cup. Flipping the cup up means you leave one of your tokens in the center room. Flipping it down means you take the token. Obviously only one token can be left in the center room at a time.

Now the problem just becomes one of having the leader collect enough tokens. The cup can start up or down, so there may be an extra token in play. Allowing the king to flip the cup out of sight of the prisoners allows him to add or remove a token from the system with each flip. Thus if the prisoners start with a total of x tokens among all of them, over the course of the game that total may change to between x - k and x + k + 1 (+ 1 there because the cup might start sitting upright).

Now, the solution is that all prisoners except the leader start with 2k + 2 tokens (so the prisoners start with a total of (n - 1)(2k + 2) tokens. The leader will say yes once he has collected (n - 1)(2k + 2) - k tokens. We need to show that the leader can always collect this many tokens, and that he cannot get this many tokens unless ever prisoner has left at least one token in the center room.

We can see that the leader can always collect this many tokens because the king can take at most k tokens out of play leaving only (n - 1)(2k + 2) - k tokens. Since all players will be called an arbitrary number of times, they will all get a chance to leave all their tokens in the center room and the leader will get a chance to pick them all up (the ones that the king doesn't take).

Now consider the case where one prisoner is not called out for a very long time and all other tokens are allowed to be transferred to the leader first. In addition we will assume that the cup starts up and that the king adds k tokens to the system. In this case, there are (n - 2)(2k + 2) + k + 1 = (n - 1)(2k + 2) - 2k - 2 + k + 1 = (n - 1)(2k + 2) - k - 1 tokens in play. This is one less that the required number of tokens for the leader to say yes, so he can't possibly say yes until that last prisoner comes out and gets to transfer one of his tokens to the leader.

That is a bit hand wavy, but I think it is a good proof. I have no idea if this is the best possible solution, though. I have good reason to believe that it is not the fastest (if the king chooses who to bring out arbitrarily). Check out http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisonersLightBulb if you are interested in this type of problem and want to figure out the "fastest" solution. That whole forum is full of really hard math puzzles.

-- corygwilliams AT google's mail place

The original is commonly known as "100 Prisoners and a Light Bulb":

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisonersLightBulb

http://www.ocf.berkeley.edu/~wwu/papers/100prisone rsLightBulb.pdf

(the latter paper mentions a slashdotting, btw)

also see:

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisoners2LightBulbs

The original is commonly known as "100 Prisoners and a Light Bulb":

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisonersLightBulb

http://www.ocf.berkeley.edu/~wwu/papers/100prisone rsLightBulb.pdf

(the latter paper mentions a slashdotting, btw)

also see:

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisoners2LightBulbs

The original is commonly known as "100 Prisoners and a Light Bulb":

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisonersLightBulb

http://www.ocf.berkeley.edu/~wwu/papers/100prisone rsLightBulb.pdf

(the latter paper mentions a slashdotting, btw)

also see:

http://www.ocf.berkeley.edu/~wwu/riddles/hard.shtm l#100prisoners2LightBulbs

http://www.ocf.berkeley.edu/~wwu/riddles/intro.sht ml/

Has nearly all the ones I've seen so far, plus oodles more. Keeps me distracted for hours on end. Warning: doesn't give solutions, can be frustrating.

Right here.

Incidentally, that page has been slashdotted in the past.

Is ..:: Riddles ::... In has (amogst others) the famous "prison with a lamp" problem:

100 prisoners are imprisoned in solitary cells. Each cell is windowless and soundproof. There's a central living room with one light bulb; the bulb is initially off. No prisoner can see the light bulb from his or her own cell. Each day, the warden picks a prisoner equally at random, and that prisoner visits the central living room; at the end of the day the prisoner is returned to his cell. While in the living room, the prisoner can toggle the bulb if he or she wishes. Also, the prisoner has the option of asserting the claim that all 100 prisoners have been to the living room. If this assertion is false (that is, some prisoners still haven't been to the living room), all 100 prisoners will be shot for their stupidity. However, if it is indeed true, all prisoners are set free and inducted into MENSA, since the world can always use more smart people. Thus, the assertion should only be made if the prisoner is 100% certain of its validity.

Before this whole procedure begins, the prisoners are allowed to get together in the courtyard to discuss a plan. What is the optimal plan they can agree on, so that eventually, someone will make a correct assertion?

I'm sure this has been on slashdot before but nobody's mentioned it. http://www.ocf.berkeley.edu/~wwu/riddles/intro.sht ml Almost any logic problem you've heard of is described, and discussed on that site.

Here's a nice review of the application of this legal doctrine to cyperspace disputes. It includes bulk email and so on.

Obviously this solution is expensive and inconvenient because users have to get their hands on specialized hardware and carry it. Furthermore, synchronization issues need to be addressed. I don't think this time regulated random generators use atomic clocks, GPS or NTP... Also what about visually-impaired users? All these issues would not exist if they simply used the Secure Remote Password from Standord. http://en.wikipedia.org/wiki/Secure_remote_passwor d_protocol (check references for more details). There already exist SSL/TLS implementations of this protocol. A very good solution that uses SRP is suggested inhttp://www.cs.berkeley.edu/~tygar/papers/Battle_ against_phishing.pdf (previously slashdotted). All the user has to do to verify a site is to compare images that are derived as visual hashes of a common secret session key (used for encryption) and exchanged random data. Audio hashes can also be used for the visually impaired.

Yeah, there is plenty of evidence to support the idea that dinosaurs were hot blooded. There is, however, an equal amount of evidence to support the theory that they were cold blooded. Just what distinction you choose to separate dinosaurs from reptiles depends on which theory you support.

Ignore the differentiation of whales from mammals. I'm sure it was an oversight.

Yeah, there is plenty of evidence to support the idea that dinosaurs were hot blooded. There is, however, an equal amount of evidence to support the theory that they were cold blooded. Just what distinction you choose to separate dinosaurs from reptiles depends on which theory you support.

Ignore the differentiation of whales from mammals. I'm sure it was an oversight.

> I was always under the impression that David Patterson at
> Berkeley and John Hennessy (now President of Stanford) invented
> the RISC architecture and then took it to Sun? The Patterson bio
> linked to above seems to indicate that he did invent the
> RISC architecture. Huh.

Nope. The IBM 801 project began in 1975, and I'm fairly sure they had a machine up and running 2 or 3 years later, perhaps sooner.

The Stanford work on MIPS didn't begin until 1981. I was in John's group at Stanford at that time, though not working on RISC, and I distinctly remember that among the factors that led to the university work on RISC was early information on the 801 that started to come out of IBM. I believe that the Berkeley work was roughly contemporary with the Stanford project, though perhaps a bit ahead. Dave Paterson's bio claims that RISC I was the first VLSI RISC, and I suspect that's true. Hard as it may be to believe now, the IBM 801 was built at a time when even a simple CPU took many chips. I recall the actual box being perhaps 2-3 feet long, and maybe 1.5 feet high.

In any case, the IBM 801 work clearly came years earlier than either the Stanford or Bekerely projects, and I think John H. and Dave P. would be the first to acknowledge the seminal work of John Cocke and the IBM 801 team. My impression is that the respect was mutual, and that all involved agreed that both the Standford and Berkeley teams made very important later contributions.

I was always under the impression that David Patterson at Berkeley and John Hennessy (now President of Stanford) invented the RISC architecture and then took it to Sun? The Patterson bio linked to above seems to indicate that he did invent the RISC architecture. Huh.

While SPARC may have been the first VLSI based RISC architecture, I think the IBM 801 architecture may have preceded it. John Cocke at IBM was a seminal thinker in the area and may have developed the RISC concept and was awarded a Turing award for this work, so he might have a claim for the innovation.

I was always under the impression that David Patterson at Berkeley and John Hennessy (now President of Stanford) invented the RISC architecture and then took it to Sun? The Patterson bio linked to above seems to indicate that he did invent the RISC architecture. Huh.

UC Berkeley's School of Information Management & Systems has an excellent class on Open Source. The syllabus is available online: http://www.sims.berkeley.edu/academics/courses/is2 96a-2/f05/syllabus.html

Pam Samuelson, Steven Weber, and Mitch Kapor are team-teaching a course on Open Source this semester in UC Berkeley's School of Information Management Systems (SIMS). The schedule of readings is available online. In your situation, dealing with Continuing Education students, many of whom you expect to have programming experience, I would pick and choose from the readings on this syllabus and add your own components geared to your audience. Something participatory would be a good idea. If you do get all programmers, have them form teams and pick projects to contribute to and write up their experiences. If you get some non-programmers allow them to form a team working on contributions to open source-like projects such as Wikipedia or something.

IAAP, and while I see where you're coming from I'd actually make the argument in the opposite direction.

A previous poster has already noted a paper (astro-ph/0508377) which quickly followed this one and refuted its conclusions (I have seen other physicists describe the same point elsewhere). It seems (though I have not yet checked the math myself) that the authors made an honest error, and they weren't modeling the situation they thought they were. In addition to the self-gravitating cloud of gas they were trying to model, the metric also includes a disk-shaped "singularity" - essentially a very thin, very heavy disk in the plane of the galaxy. It is this unphysical disk which is responsible for the effect they observe.

It's also worth noting that dark matter has MANY independent lines of evidence pointing to it (rotation curves, gravitational lensing, the cosmic microwave background, large scale structure, element abundances... see here). Galactic rotation curves were the first such evidence, but arguably they are the weakest today. I'm still more than willing to believe that the dark matter paradigm could be wrong, and this result would be VERY interesting if true, but there would still be lots left to explain. This is how science works, of course - idea gets put forward, it gets checked by others, the community works out what to think of it.

This also makes me think of the current controversy over intelligent design, but in the opposite way to the previous poster. Look at the Slashdot thread around us. Hundreds of people are posting to say how relieved they are that dark matter doesn't exist, since they always thought it was too weird and that those pointy-headed physicists were out of touch with their own good common sense. They feel very confident doing this, even though (1) they admit that they don't understand the evidence and reasoning they are talking about (even as some of them chastise physicists for the "basic error" they were making), and (2) the reasoning itself was later shown to be flawed. Several posters have tried to make follow-up postings showing that this reasoning has been refuted, but they can't hit every discussion thread (and it's not clear it would do any good if they did). As with the anti-evolution "controversy", people latch on to sensational headlines of flaws in basic science and simplistic errors by scientists to believe whatever they felt most comfortable believing to begin with. From there, it's an uphill battle to get the truth out there.

(You'll also need to bring some foil to protect the monitor against Tempest attacks... and some loud music to prevent eavesdroppers from recording your keystrokes... and some tape to cover all the LEDs...)

Print, film, magnetic and optical storage media produced 5 exabytes of new information in 2002 according to these Berkeley researchers. They have been estimating the amount of information created each year and how much it is growing.

Google probably used their figures. Factor in the speed of Google's spiders and the current rate of their growth - and I am sure 300 years is very close to the answer they found with their "math exercise."

Time to bust out the holy wars.

I like the 68000 because it has so many registers but I think all in all in the 80386 is the better CPU.

For reference, consider:

http://www.freescale.com/files/32bit/doc/reports_p resentations/MC680X0OPTAPP.txt

http://www.df.lth.se/~john_e/gems/gem0028.html

http://linux.cis.monroeccc.edu/~paulrsm/doc/trick6 8k.htm

http://www.csua.berkeley.edu/~muchandr/m68k

Right off the wheel, we notice that the 68000 did not support 32 bit multiplecation at all. Doesn't sound too much like a 32 bit chip to me. Compare that to Intels quirky IMUL, which I believe puts the result into EAX, EDX to get a real 64 bit result.

Integer math was faster clock for clock on the 386. Compare things like 68K register addition to Intel register addition. There's no comparison.

Compare

http://www.gamedev.net/reference/articles/article2 14.asp#ADC

to

http://www.df.lth.se/~john_e/gems/gem0028.html

Whenever you did any 32 bit pointer math on a 68k, you paid a huge, huge performance penalty. It was always more efficient to do things in 16 bit PC relative addressing.

The 68K had no concept of isolated memory or tasks. So systems like the Amiga and the Macintosh would run without any isolation between processes. I was an Amiga fan boy and I used to get that GURU meditation error so much that it was not even comical.

The tragedy of the 386 architecture was actually Microsoft and not Intel. DOS and Windows did not use even the 386 chip to its fullest capability for memory management. MS users would have to wait until Sept 1995, almost 10 years after the 386, for a true 32 bit operating system.

SETI's search parameters are based on some really well though out assumptions about how ET civilizations might try communicating.

You wish. There are two groups that dominate the public arguments for passive SETI: those who directly anthropomorphize alien civilizations and those that use a thought-out logic that is still steeped in assumptions of human-like intelligence. While this may be reasonable both are really large asumptions that limit our search. The anthro's are screwed becuase any signals using channels of the EM spetrum that we like will have to compete with cellphones, radios random electronics - even those in the detector.

The reasonable logic fellows, such as Carl Sagan, simply look at what parts of the radio spectrum that has no significant natural sources of interference. This is the dominate method in current projects. However, there are many of these dead spots. The most prominate quiet channel to a human being the channels surrounding the frequency of hydrogen's spectrum (aka the 'watering hole.') It is in this streach of frequencies that projects like SETI@home are looking for signals.

The deafing silence of this area should be telling: there seems to be Nothing - natural or artificial - at those frequencies. Like looking for lost keys by researching the same empty spots, SETI carefully combs these small streaches frequencies for any possible signal. This technique is not problematic becuase of focusing on parts of the Electromatnetic (EM) spectrum that humans find economicaly and technically useful but becuase the eschew those spans of spectrum on purpose. Instead of assuming human-like intellegence, the watering-hole gazers are assuming a (still) human-like intellegence acting in the opposite fashion that a human would.

In a technological society where eletromagnetic radition is reasonably well understood it shouldn't take too long to figure out that the radio portion of the EM spectrum is really useful, especially if their physiology remotely resembles anything on Earth.

Considering that if the anthropomorphism above is plausible then they would use similar channels that we use. Not the 'water hole' or other quiet parts of the EM spectrum, but transmissions in area that we find usefull. In the end, we may be getting detectably strong ET signals right now. But, we cannot hear them for the chatter of our own civilization which prefers to use the same channel for repeating Brittney Spears' 3 top selling songs.

Either purposfully sent of just radio chatter, any signal is so attenuated at stellar distances that you must search for the precise signal used in the transmission. Both group assumes that a society would setup and transmit for thousands if not millions of years a steady and powerfull signal or set of targets signals. There is a huge cost for powering and maintaining such equipment over such a timespan. There is very little payback on the timescales of our societies for performing such an ET-friendly transmission. This means billions of channels in the spread of frequencies the FCC allocates to 1 station to play Brittney Spears music. And any signal is likely to be little more than a carrier signal for the local pop-music or military radar. Hence the huge processing requirements for projects like SETI@home to sift such needles in the radio haystack.

To the benefit of both, the encyclopedia galactica may be being beemed at us right now. We just may have the dial on the wrong station.

SETI's search parameters are based on some really well though out assumptions about how ET civilizations might try communicating.

You wish. There are two groups that dominate the public arguments for passive SETI: those who directly anthropomorphize alien civilizations and those that use a thought-out logic that is still steeped in assumptions of human-like intelligence. While this may be reasonable both are really large asumptions that limit our search. The anthro's are screwed becuase any signals using channels of the EM spetrum that we like will have to compete with cellphones, radios random electronics - even those in the detector.

The reasonable logic fellows, such as Carl Sagan, simply look at what parts of the radio spectrum that has no significant natural sources of interference. This is the dominate method in current projects. However, there are many of these dead spots. The most prominate quiet channel to a human being the channels surrounding the frequency of hydrogen's spectrum (aka the 'watering hole.') It is in this streach of frequencies that projects like SETI@home are looking for signals.

The deafing silence of this area should be telling: there seems to be Nothing - natural or artificial - at those frequencies. Like looking for lost keys by researching the same empty spots, SETI carefully combs these small streaches frequencies for any possible signal. This technique is not problematic becuase of focusing on parts of the Electromatnetic (EM) spectrum that humans find economicaly and technically useful but becuase the eschew those spans of spectrum on purpose. Instead of assuming human-like intellegence, the watering-hole gazers are assuming a (still) human-like intellegence acting in the opposite fashion that a human would.

In a technological society where eletromagnetic radition is reasonably well understood it shouldn't take too long to figure out that the radio portion of the EM spectrum is really useful, especially if their physiology remotely resembles anything on Earth.

Considering that if the anthropomorphism above is plausible then they would use similar channels that we use. Not the 'water hole' or other quiet parts of the EM spectrum, but transmissions in area that we find usefull. In the end, we may be getting detectably strong ET signals right now. But, we cannot hear them for the chatter of our own civilization which prefers to use the same channel for repeating Brittney Spears' 3 top selling songs.

Either purposfully sent of just radio chatter, any signal is so attenuated at stellar distances that you must search for the precise signal used in the transmission. Both group assumes that a society would setup and transmit for thousands if not millions of years a steady and powerfull signal or set of targets signals. There is a huge cost for powering and maintaining such equipment over such a timespan. There is very little payback on the timescales of our societies for performing such an ET-friendly transmission. This means billions of channels in the spread of frequencies the FCC allocates to 1 station to play Brittney Spears music. And any signal is likely to be little more than a carrier signal for the local pop-music or military radar. Hence the huge processing requirements for projects like SETI@home to sift such needles in the radio haystack.

To the benefit of both, the encyclopedia galactica may be being beemed at us right now. We just may have the dial on the wrong station.

  This example illustrates one of the fundamental principles of the economic analysis of liability: it should be assigned to the party that can do the best job of managing risk. For most risks associated with A.T.M.'s the banks are in better position to manage risks than are the users, so they should end up with most of the liability. But you wouldn't want the users to escape all liability for their actions, since they would then tend to be too sloppy. The right balance should depend on the influence that each party has over the possible risk factors.

The Internet is the result of the voluntary interconnection of a bunch of independent networks, based upon a.common set of protocols. It's the closest the modern world has come to anarchy - there is a hierarchy of technology which supports it, but real control is dispersed, because participation is by voluntary consent. Someone doesn't like the way it works - fine, here's some tools, they can go off and build their own. And that can even work, if enough people agree that's what is useful to them ( http://www.internet2.org/ ). But more likely, they'll quickly come to the realization that the Internet isn't technology or even a network, it's communications amongst consenting peers. It's part of the evolutionary path human communications has taken.

Yes, cars were invented. They myriad ways we use cars evolved from that invention.

Or maybe it's more like Myxomycophyta ( http://www.ucmp.berkeley.edu/protista/slimemolds.h tml ), in that the most interesting thing is the sum of the whole, not the components.

Don't look down on the Texans. It has one of the highest ranked computer engineer programs in the country. I've heard of Doug Berger before and we have read his research papers and use his simulators (made between him and Todd Austin of Wisconsin) in our graduate classes at CMU (I'm BS&MS ECE, CS '01).

I didn't ask about how well their program is rated. Has UT produced any programs that people use? E.g.

MIT -- Kerberos
Berkeley - RISC, BSD Unix, RAID, TCP/IP networking as standard OS feature
Stanford -- RISC
Cornell -- Ensemble, Horus, Spinglass -- distributed programming toolkits
Caltech -- Carver Mead (VLSI method, VLSI tools, machine vision)


UT -- a simulator that you've used. What sort of simulator, please?

E.g. Berkeley developed SPICE, a tool used to simulate circuits. Last I heard, it was the standard tool to use for that stuff. Here's the project page: http://bwrc.eecs.berkeley.edu/Classes/IcBook/SPICE /

Austin also has a high number of tech companies around - heck, AMD, IBM, Intel, Freescale, just to name a few.

I didn't ask what firms work there. I want to know what software people at UT have made that is worth talking about.

The guards pages are only practical for larger allocations due to hardware limitations, as you say. Strings are protected by different means such as Propolice; in order to minimise the overhead of Propolice, it "detects" strings (as opposed to byte buffers) and specifically protects them with canaries to try and find overflows that would smash the stack (the local variable re-arrangement tries to put these buffers as close to the canary as it can at compile time). The string detection is a heuristic as gcc doesn't maintain quite enough type information when it reaches the code generation parts which Propolice touches. Also, there is a simple bounds checker built into gcc which looks for incorrect use of statically allocated buffers with some standard functions such as strncpy or sscanf (you'd be amazed how many people specify the buffer size wrong to a bounded function).

None of these are perfect of course, but each of the techniques has found bugs (hundreds in the case of the two mentioned above) in our source and ports trees. It's also great to see projects like CCured being developed at Berkeley; although the overhead is just slightly too high to be used "out of the box" right now, it still works great with select applications such as Apache. The underlying tool, CIL can compile most of the OpenBSD source tree (including the kernel) now, and the result even boots when using a null source-to-source transform.