After all the basic tech hasn't changed all that much.
On the contrary, the basic tech has changed enormously in three areas: computing, materials, and computing.
1) Computing: on board computing is vastly lighter than it was in 1975, when the shuttle was designed. More computing power on the spacecraft may enable optimizations that will save weight, improve reliablity, etc.
2) Materials: the late 20th century saw a huge revolution in materials design, to the extent that we can build things that are far stronger and lighter than we could in 1975. Likewise there has been progress in high temperature materials, due in part to the work on the original shuttle.
3) Computing: the original shuttle wasn't exactly lofted on a hanger floor the way the DC-3 was, but the simulation capability that existed in 1975 was tiny and rudimentary compared to what it is today. So we can expect new vehicles to be more strongly optimized, the engines to have higher Isp's, better reliability, etc.
the lunar and Mars space craft will undoubtly be assembled in orbit from modules, and carry along a CEV docked on the side to the astronauts can return to earth after it's over.
Err...wouldn't it make a good deal more sense to leave the CEV in Earth orbit, rather than expending vast amounts of energy to move all that dead weight to and from Mars? Or to pop one up for the return crew when they return?
It seems like they had more reason than just a watch:
"One of the detainee's known aliases was on a list of captured hard drives associated with a senior al Qaida member".
Abdullah Kamal or Kamel is an extremely common name. Google on the exact phrase and you'll get over 1,000 hits. Do you think all those links are to the same person? Do you think all those people are terrorists?
For comparison, I googled on my own name, which turned up about 22,000 hits (I'm widely published online and also have the same name as a mid-rank movie actor.) I used the informal form of my first name (that would be "one of my aliases" in tribunal-speak) and looked for the exact phrase. On the first page there is someone who not only has my first and last name, but also my middle initial and who is also a professional engineer. If he turns out to be affiliated with some wacky American militia does that mean I should fear for my freedom?
...who knows what the classified evidence might be.
That is exactly my point: no one but the demonstrably incompetent members of the tribunal knows, and they can't even get the model of the guy's watch right. We don't even know for sure what name they claim was on the al Quaeda hard drive, and we don't know what context it was in.
I'm not suggesting that all evidence be made fully public, but for example in Canada we have a system under which detainees can have the classified evidence in their cases reviewed by a judge. That's still imperfect--I'd like to see some kind of security cleared advocates for the detained, who would be working for them, not the state. For good or ill Anglo-Saxon jurisprudence is adversarial, and we need an advocate for the accused who is not a lackey of the court.
So then what you're saying is that string theory, multiple universe theory, the theory of evolution and a good deal many others are superstitions because they can't be tested?
You are confusing "haven't been tested yet" with "can't be tested."
"Can't be tested" in this context means "can't be tested, even in principle." There are oodles of ways we can test string theory, for example. It makes definite predictions about reality. If reality is not that way, string theory is false. It is unfortunate that string theory's predictions are for conditions that we don't know how to experimentally realize, which is why no one takes string theory very seriously (except string theorists, whom we keep around for their entertainment value.)
In contrast, the proposition "The God of the Bible exists" is a something that the Bible itself says cannot be tested. God cannot be bid. End of story.
With regard to evolution, there are all kinds of tests, from experiments on the spontaneous generation of amino acids to predictions regarding the degree of variation in adaptive vs irrelevant traits.
For Intelligent Design the number of tests is exactly zero, and always will be.
After all, these are terrorists, right? Well, how do we know? Is the military infallable? Is every accused person guilty?
In fact we know with as much certainty as we know anything that some of the 500 people incarcerated in Guantanomo Bay are not terrorists. Simple statistics is all that is required to prove this. We know that the cops sometimes arrest the wrong person, and that for that reason we have courts. And we know that sometimes courts convict the wrong people, and for that reason we don't have the death penalty (oops, sorry, you guys in the U.S. do, don't you?)
We also know that the Guantanomo detainees were captured in an environment very much subject to "the fog of war", which gets used as an excuse every time the U.S. military fucks up and kills a few Canadians.
Given all this, it is extremely doubtful that the error rate in accusations of terrorism is less than 1%. If it is 1%, then on average we would expect 5 innocent people to be incarcerated in Gauntanomo Bay with no rights. A Poisson distribution with a mean of 5 has P(0) = 0.0067, so there is a 99.3% chance that there is at least one innocent in Gauntanomo Bay, even under these extremely conservative assumptions.
Given that the U.S. military tribunals that are passing judgment on the detainees believe that wearing a Casio watch constitutes evidence of terrorism it is pretty clear that the rate of incarceration of innocents is much higher than this. It is also worth noting that the tribunal does not even get the model of the watch correct--the F91 does not have a compass. It makes one wonder what other mistakes they have made in the evidence that still remains classified.
"...programming language notation is different from the working notations of mathematicians and physicists and chemists. Why can't we bring them close together? That's one of the conjectures we have in Fortress. What if we tried really hard to make the mathematical parts of a program look like mathematics?" he adds.
This is simply not a problem most mathematicians, phyicists or chemists have. I've never said, "Damnit, why doesn't the FORTRAN code for this thing look more like mathematics!?" Neither has anyone I know.
The best high-level mathematical language in the world--Mathematica--has input that looks very little like mathematics. Integral[Exp[x],{x,0,1}] expresses the mathematics very elegantly in a pure ASCII, standard, portable, form. But it looks nothing like what you'd write on a piece of paper, if that's what "looking like mathematics" means.
Furthermore, there has been a language that looks a great deal like (parts of) mathematics: APL. No one uses it, and part of the reason is that the statements are far too compact--i.e. "mathematics like"--to be readable.
And finally, what does "mathematics" look like? Different fields use radically different notations and conventions. This is particularly true when you start looking across math, engineering and physics. Even different branches of physics are apt to use different notations for the same thing, and worse yet the notation changes over time--go look at any pre-war book on quantum mechanics and you'll see all these "Sp" things where today you'll see "Tr". And things like vectors are typically typeset in bold, but have over-scored arrows when you write them by hand. Which of these "looks like mathematics"?
Locking any of this down in a programming language is just not useful.
What these guys have done is found a novel application of a relatively well-known means of generating extremely high electric fields. This is good, and may produce more compact, robust neutron generators than we currently have.
But it is clear from the article--and the basic physics--that this isn't a practical means of generating fusion power. This is just another hot fusion mechanism--it isn't "room temperature". The deuterium ions from the gas discharge are accelerated by the field and smash into the ErD surface with high energies.
The interaction cross-sections are such that virtually all of the D ions will slow down without fusing, and the energy that went into accelerating them will be only recoverable as heat, with the usual thermodynamic (in)efficiencies. The DD fusion cross-section just isn't high enough to overcome those losses.
...if it's strong enough to suspend dust in densitites like this...
Densities like what? These are enhanced images.
They've taken multiple frames, subtracted them to get images that are uniform except where something has moved/changed, increased the contrast in the subtracted images and added them back in to the originals. This is a good way of making things that change really stand out, but is not useful for even qualitative estimates of the dust density.
In the original images you can barely see anything--the dust density is extremely small. It may still be sufficient to yield signifcant errosion over geological (areological?) timescales, though.
Marx's theory is quite fundamentally based on his labour theory of value, which is false.
The failure of Marxist states is due in part to the vile incompetence of the individual dictators who ran them. But the most competent dictator in the world couldn't keep a Marxist system afloat for more than a few years without inflicting poverty, mass incarceration, starvation and killings on the people.
Claiming that such systems "aren't really Marxist" is like claiming that people who fail to turn lead into gold "aren't really alchemists" and so can't be used as evidence that there is something a bit fishy about alchemy.
Despite the weight (or was that mass?) of immemorial tradition, the units of specific impulse are not seconds. Pounds force are not pounds mass. Giving them the same name does not allow one to cancel them, any more than one can cancel the "d"'s in a derivative.
The units of Isp are lb-f*s/lb-m, or better yet, N*s/kg. lb-m isn't even a good Imperial unit--it ought to be slugs.
Isn't it about time rocket scientists got with the 21st century?
So if I understand the argument correctly, we have a problem that is due to a whole bunch of antecedent factors, like bad law, muddy thinking on the difference between a property right and a temporary monopoly, etc. Your proposal is, rather than to fix the cause, to apply a band-aid solution that may, theoretically, ameliorate some aspects of the symptoms.
That is, you're proposing a kludge.
That's not good engineering, and it's not good law either.
While it might be of historical interest to instantiate it, Turing's original test has always struck me as being very strange, and very much a local product of his highly sexist times. After all, why would you expect to be able to tell the difference between a male and female chat participant in the first place? Why bring gender into it at all? It isn't like gender has anything to do with what we usually think of as intelligence, unless we focus on some very narrowly defined technical skills (males slightly better on average at certain kinds of spatial processing, etc.) which aren't likely to come up in an electronically-mediated social interaction.
They went to a University library and obtained help from a trained librarian.
Don't make me laugh. While in some specialized areas there might be a few librarians who are useful (mostly to scholars who share their narrow field of expertise) for the most part librarians view users pretty much the same as sysadmins do: nasty people who want to get their dirty hands all over their nice pristine books/systems.
I'm a physicist, and I have never met a "trained librarian" who can tell a neutron from a neutrino. "Trained librarians" who wanted to "help me" find the stuff I was looking for were the first obstacle to overcome when doing research. Nor was this a problem found only in a few universities--it was ubiquitous, including places like Caltech and UCSD. In fact, you'll find that most physics departments up until recently had their own "internal library" for their own use, because the central librarians first duty always seemed to be making the books and journals as inaccessible as possible.
However, there is another model called the multi-regional model that states Homo sapiens evolved sperately on each of the different continents. How could this happen you say? Because enough interbreeding went on to maintain species integrity. (emphasis added)
If populations are interbreeding sufficiently to maintain genetic homogeneity then they were not separate in the relevant sense, and cannot be characterized as evolving separately. "Evolving simultaneously as one large, well-connected, interbreeding population" would be a more accurate description.
Such an event is a priori improbable, although that does not mean it is impossible.
One important prop for the out-of-Africa model is that the most currently plausible models of speciation are based on small, isolated populations. For example, the chromosome fusion that happened at some point in our divergence from our simian ancestors could not have happened successfully in a large, dispersed population.
Not all speciation depends on such dramatic events, but a small, isolated population will always be more prolific of new species than a large, dispersed one if only because the trend of local selective pressure will consistent across the whole population. It is hard to imagine the same selective pressures acting in a sufficiently consistent manner across a very large geographic area.
Of course, just because something is hard to imagine doesn't mean it didn't occur.
Remember, you only find what you are looking for.
Nonsense. Scientists find stuff all the time that we weren't looking for. Sometimes we ignore it if our preconceived ideas conflict with it, but we do so at our peril, because someone else will notice it, publish it, win the Nobel and get all the hot chicks.
You laugh, but it's fairly well-established that ~10% of babies are fathered by someone other than their mother's socially pair-bonded mate.
Here is an extensive summary of studies. As the summary suggests, rates of misattributed paternity vary widely, from about 1% in some areas to over 20% in others, mostly depending on social/economic status. However, the fact is, most of us are almost certain to have some interlopers in our heritage--we are all mongrels under the skin!
Humans are just the tool that our genes use to make more genes.
If so, they've chosen a fantastically inefficient way to do it, haven't they? You could have a dozen kids, and still lose 0.024% of your genes forever. If you have two kids, a full 1/4 of your genes would never be transmitted to posterity.
Sexual reproduction is a good trade-off for an organism, but a terrible deal for the organism's genes.
Weird how that hasn't been a big problem for micro-organisms, corals and other multi-cellular and polyp creatures that don't experience death by old age.
We know where famine comes from. In the past century it came exclusively from governments using control of the food supply as a weapon. The famine in Darfur is the most recent example of this.
The problem of landless small farmers in the developing world is real. So is the problem of GM crops that get loose. And Monsanto is pretty much the incarnation of evil. But any account of the looming GM disaster that leaves the deep complicity of governments out of the picture is radically incomplete.
I don't get why people keep saying it will "never" work. It's a hard problem, but I'm aware of no physical laws that are violated by BMD.
People say BMD will never work because they are aware that in the face of an even moderately successful BMD system terrorists and rogue states (against whom the current BMD system is targeted) will opt to deliver nuclear weapons to American cities by stealth.
The canonical stealth method of delivery involves hiding nuclear bombs in bales of marijuana. Drug interdiction doesn't violate any physical laws either, but not all problems are physics problems.
The event horizon is a singularity in the co-ordinate system of distant observers. It is correct to say that Planck-scale effects won't remove the event horizon in the sense that we still won't be able to observe much inside it. But they will remove the singularity of the event horizon, as they will also remove the singularity of the infinite density at the centre (the singularity you say black holes "contain").
I'm using "singularity" in the mathematical sense, not the physical sense, which is reasonable because physically there are no singularities (we hope.) The proposed model includes an event horizon, but not the (mathematical) singularity at the event horizon. It does this on a scale much larger than the Planck scale, and so will have much larger observable effects on the physics of the horizon.
If you choose to define "black hole" in terms of an event horizon, then the new theory is just a theory of black holes. But certainly many people make a point of identifying black holes with singularities, which means if you get rid of the singularities, you get rid of the black holes.
The problem with black holes is that they are, by definition, singularities. Unadulterated GR says that matter becomes infinitely dense, that the event horizon is infinitely sharp, etc.
This isn't very satisfactory, and we've known for a long time that something interesting must happen to smooth out these infinities at the Planck scale (something to the tune of 10^-33 cm). In this limited sense, we've known all along that "strict" black holes don't exist: that is, the pure, mathematical singularities that GR predicts must be smoothed out by quantum effects at very short scales.
In keeping with the sloppy thinking that makes physics the Queen of the Sciences (IAAP, as it happens) we've decided that those Planck-scale effects don't really count, and implicitly modified our concept of "Black Hole" to accomodate them.
What this guy is playing with is the idea that something interesting happens on much larger scales. In this case, although there is still something like an event horizon, it is no longer a singularity in the space-time co-ordinates of distant observers, but rather a phase transition in the quantum-mechanical vaccuum. He is proposing a macroscopic quantum mechanism for smoothing out the singularity.
This is a nice move for two reasons: the study of quantum critical behavior has a variety of analogues such as superfluids that can be studied in the lab; and there are physical phenomena that he predicts which may explain a variety of otherwise problematic observations. These are: high-energy positrons from the centre of our galaxy (where there is a 10^6 solar mass dense object); gamma-ray bursts; cosmological dark matter.
Overall, this is a nice, plausible, interesting approach to a serious problem.
For what I shall tell concerning them is not an Hypothesis but most rigid consequence, not conjectured by barely inferring 'tis thus because not otherwise or because it satisfies all phaenomena (the Philosophers universal Topick,) but evinced by the mediation of experiments concluding directly and without any suspicion of doubt. --Newton (in a letter to Oldenburg, regarding the colours of light in the Opticks)
While hypothesis and refutation is a useful tool in science, it is not the only tool, and particularly when one is engaged in the creation of new concepts we can go considerably beyond it.
Protein biomarker analysis is still very much in its infancy, and while the results to date have been promising, the sample sizes have been small and the data quality frequently problematic.
For example, early protein biomarker datasets for ovarian cancer detection were a catalog of artefacts, and even today many analyses are run on datasets that have not had proper feature detection done on them. This results in the discovery of "patterns" that involve structures that are clearly non-physical (for example, peaks that are much narrower than the resolution of the apparatus.)
There are also fundamental difficulties with high false discovery rates when running pattern recognition software on these data. Statistically speaking, the question you are asking is: what are the odds that I can find N channels that a classification algorithm can use to distinguish class A from class ~A? When you have thousands of channels, and N is somewhere between 2 and 10, and you have only a few dozen samples, the a priori probability of being able to find a classifier is essentially unity.
So while I think this whole approach to disease is interesting, it is very likely that one could achieve similar results to the ones reported in this abstract even if the data were pure noise.
One of the things that created the Y2K problem was the unexpected longevity of code. No one coding in the 80's seriously believed that their code would still be used as the basis for released applications in the late '90's.
On the basis of things like this we should expect digital content to remain of interest considerably longer than we might currently expect. There are other reasons to believe this: I own a number of books that are more than 40 years old, and some of them are not only useful but still quite current (Heitler's Quantum Theory of Radiation, for example.) And I'm reading a novel at the moment that was printed over 100 years ago.
The nice thing about paper is that if you leave it alone under reasonable conditions it persists pretty well. If digital media can't do the same, then there is a significant hidden cost involved in using them. For large organizations this cost is just one component of the usual process of archival data management, but for the average person it is something new.
It isn't the universe that has to be elegant, but our theory of it. The reason why is that we aren't very smart, and theories with fewer free parameters are a lot easier for us to understand.
Slashdot Mirror
After all the basic tech hasn't changed all that much.
On the contrary, the basic tech has changed enormously in three areas: computing, materials, and computing.
1) Computing: on board computing is vastly lighter than it was in 1975, when the shuttle was designed. More computing power on the spacecraft may enable optimizations that will save weight, improve reliablity, etc.
2) Materials: the late 20th century saw a huge revolution in materials design, to the extent that we can build things that are far stronger and lighter than we could in 1975. Likewise there has been progress in high temperature materials, due in part to the work on the original shuttle.
3) Computing: the original shuttle wasn't exactly lofted on a hanger floor the way the DC-3 was, but the simulation capability that existed in 1975 was tiny and rudimentary compared to what it is today. So we can expect new vehicles to be more strongly optimized, the engines to have higher Isp's, better reliability, etc.
the lunar and Mars space craft will undoubtly be assembled in orbit from modules, and carry along a CEV docked on the side to the astronauts can return to earth after it's over.
Err...wouldn't it make a good deal more sense to leave the CEV in Earth orbit, rather than expending vast amounts of energy to move all that dead weight to and from Mars? Or to pop one up for the return crew when they return?
--Tom
Deut 22:11
"One of the detainee's known aliases was on a list of captured hard drives associated with a senior al Qaida member".
Abdullah Kamal or Kamel is an extremely common name. Google on the exact phrase and you'll get over 1,000 hits. Do you think all those links are to the same person? Do you think all those people are terrorists?
For comparison, I googled on my own name, which turned up about 22,000 hits (I'm widely published online and also have the same name as a mid-rank movie actor.) I used the informal form of my first name (that would be "one of my aliases" in tribunal-speak) and looked for the exact phrase. On the first page there is someone who not only has my first and last name, but also my middle initial and who is also a professional engineer. If he turns out to be affiliated with some wacky American militia does that mean I should fear for my freedom?
That is exactly my point: no one but the demonstrably incompetent members of the tribunal knows, and they can't even get the model of the guy's watch right. We don't even know for sure what name they claim was on the al Quaeda hard drive, and we don't know what context it was in.
I'm not suggesting that all evidence be made fully public, but for example in Canada we have a system under which detainees can have the classified evidence in their cases reviewed by a judge. That's still imperfect--I'd like to see some kind of security cleared advocates for the detained, who would be working for them, not the state. For good or ill Anglo-Saxon jurisprudence is adversarial, and we need an advocate for the accused who is not a lackey of the court.
--Tom
So then what you're saying is that string theory, multiple universe theory, the theory of evolution and a good deal many others are superstitions because they can't be tested?
You are confusing "haven't been tested yet" with "can't be tested."
"Can't be tested" in this context means "can't be tested, even in principle." There are oodles of ways we can test string theory, for example. It makes definite predictions about reality. If reality is not that way, string theory is false. It is unfortunate that string theory's predictions are for conditions that we don't know how to experimentally realize, which is why no one takes string theory very seriously (except string theorists, whom we keep around for their entertainment value.)
In contrast, the proposition "The God of the Bible exists" is a something that the Bible itself says cannot be tested. God cannot be bid. End of story.
With regard to evolution, there are all kinds of tests, from experiments on the spontaneous generation of amino acids to predictions regarding the degree of variation in adaptive vs irrelevant traits.
For Intelligent Design the number of tests is exactly zero, and always will be.
That's the difference between science and faith.
--Tom
After all, these are terrorists, right? Well, how do we know? Is the military infallable? Is every accused person guilty?
In fact we know with as much certainty as we know anything that some of the 500 people incarcerated in Guantanomo Bay are not terrorists. Simple statistics is all that is required to prove this. We know that the cops sometimes arrest the wrong person, and that for that reason we have courts. And we know that sometimes courts convict the wrong people, and for that reason we don't have the death penalty (oops, sorry, you guys in the U.S. do, don't you?)
We also know that the Guantanomo detainees were captured in an environment very much subject to "the fog of war", which gets used as an excuse every time the U.S. military fucks up and kills a few Canadians.
Given all this, it is extremely doubtful that the error rate in accusations of terrorism is less than 1%. If it is 1%, then on average we would expect 5 innocent people to be incarcerated in Gauntanomo Bay with no rights. A Poisson distribution with a mean of 5 has P(0) = 0.0067, so there is a 99.3% chance that there is at least one innocent in Gauntanomo Bay, even under these extremely conservative assumptions.
Given that the U.S. military tribunals that are passing judgment on the detainees believe that wearing a Casio watch constitutes evidence of terrorism it is pretty clear that the rate of incarceration of innocents is much higher than this. It is also worth noting that the tribunal does not even get the model of the watch correct--the F91 does not have a compass. It makes one wonder what other mistakes they have made in the evidence that still remains classified.
--Tom
"...programming language notation is different from the working notations of mathematicians and physicists and chemists. Why can't we bring them close together? That's one of the conjectures we have in Fortress. What if we tried really hard to make the mathematical parts of a program look like mathematics?" he adds.
This is simply not a problem most mathematicians, phyicists or chemists have. I've never said, "Damnit, why doesn't the FORTRAN code for this thing look more like mathematics!?" Neither has anyone I know.
The best high-level mathematical language in the world--Mathematica--has input that looks very little like mathematics. Integral[Exp[x],{x,0,1}] expresses the mathematics very elegantly in a pure ASCII, standard, portable, form. But it looks nothing like what you'd write on a piece of paper, if that's what "looking like mathematics" means.
Furthermore, there has been a language that looks a great deal like (parts of) mathematics: APL. No one uses it, and part of the reason is that the statements are far too compact--i.e. "mathematics like"--to be readable.
And finally, what does "mathematics" look like? Different fields use radically different notations and conventions. This is particularly true when you start looking across math, engineering and physics. Even different branches of physics are apt to use different notations for the same thing, and worse yet the notation changes over time--go look at any pre-war book on quantum mechanics and you'll see all these "Sp" things where today you'll see "Tr". And things like vectors are typically typeset in bold, but have over-scored arrows when you write them by hand. Which of these "looks like mathematics"?
Locking any of this down in a programming language is just not useful.
--Tom
What these guys have done is found a novel application of a relatively well-known means of generating extremely high electric fields. This is good, and may produce more compact, robust neutron generators than we currently have.
But it is clear from the article--and the basic physics--that this isn't a practical means of generating fusion power. This is just another hot fusion mechanism--it isn't "room temperature". The deuterium ions from the gas discharge are accelerated by the field and smash into the ErD surface with high energies.
The interaction cross-sections are such that virtually all of the D ions will slow down without fusing, and the energy that went into accelerating them will be only recoverable as heat, with the usual thermodynamic (in)efficiencies. The DD fusion cross-section just isn't high enough to overcome those losses.
Cool experiment, though.
--Tom
...if it's strong enough to suspend dust in densitites like this...
Densities like what? These are enhanced images.
They've taken multiple frames, subtracted them to get images that are uniform except where something has moved/changed, increased the contrast in the subtracted images and added them back in to the originals. This is a good way of making things that change really stand out, but is not useful for even qualitative estimates of the dust density.
In the original images you can barely see anything--the dust density is extremely small. It may still be sufficient to yield signifcant errosion over geological (areological?) timescales, though.
--Tom
Marx's theory is quite fundamentally based on his labour theory of value, which is false.
The failure of Marxist states is due in part to the vile incompetence of the individual dictators who ran them. But the most competent dictator in the world couldn't keep a Marxist system afloat for more than a few years without inflicting poverty, mass incarceration, starvation and killings on the people.
Claiming that such systems "aren't really Marxist" is like claiming that people who fail to turn lead into gold "aren't really alchemists" and so can't be used as evidence that there is something a bit fishy about alchemy.
--Tom
Despite the weight (or was that mass?) of immemorial tradition, the units of specific impulse are not seconds. Pounds force are not pounds mass. Giving them the same name does not allow one to cancel them, any more than one can cancel the "d"'s in a derivative.
The units of Isp are lb-f*s/lb-m, or better yet, N*s/kg. lb-m isn't even a good Imperial unit--it ought to be slugs.
Isn't it about time rocket scientists got with the 21st century?
--Tom
We Need to create an Intellectual Property Tax.
So if I understand the argument correctly, we have a problem that is due to a whole bunch of antecedent factors, like bad law, muddy thinking on the difference between a property right and a temporary monopoly, etc. Your proposal is, rather than to fix the cause, to apply a band-aid solution that may, theoretically, ameliorate some aspects of the symptoms.
That is, you're proposing a kludge.
That's not good engineering, and it's not good law either.
--Tom
While it might be of historical interest to instantiate it, Turing's original test has always struck me as being very strange, and very much a local product of his highly sexist times. After all, why would you expect to be able to tell the difference between a male and female chat participant in the first place? Why bring gender into it at all? It isn't like gender has anything to do with what we usually think of as intelligence, unless we focus on some very narrowly defined technical skills (males slightly better on average at certain kinds of spatial processing, etc.) which aren't likely to come up in an electronically-mediated social interaction.
--Tom
They went to a University library and obtained help from a trained librarian.
Don't make me laugh. While in some specialized areas there might be a few librarians who are useful (mostly to scholars who share their narrow field of expertise) for the most part librarians view users pretty much the same as sysadmins do: nasty people who want to get their dirty hands all over their nice pristine books/systems.
I'm a physicist, and I have never met a "trained librarian" who can tell a neutron from a neutrino. "Trained librarians" who wanted to "help me" find the stuff I was looking for were the first obstacle to overcome when doing research. Nor was this a problem found only in a few universities--it was ubiquitous, including places like Caltech and UCSD. In fact, you'll find that most physics departments up until recently had their own "internal library" for their own use, because the central librarians first duty always seemed to be making the books and journals as inaccessible as possible.
--Tom
However, there is another model called the multi-regional model that states Homo sapiens evolved sperately on each of the different continents. How could this happen you say? Because enough interbreeding went on to maintain species integrity. (emphasis added)
If populations are interbreeding sufficiently to maintain genetic homogeneity then they were not separate in the relevant sense, and cannot be characterized as evolving separately. "Evolving simultaneously as one large, well-connected, interbreeding population" would be a more accurate description.
Such an event is a priori improbable, although that does not mean it is impossible.
One important prop for the out-of-Africa model is that the most currently plausible models of speciation are based on small, isolated populations. For example, the chromosome fusion that happened at some point in our divergence from our simian ancestors could not have happened successfully in a large, dispersed population.
Not all speciation depends on such dramatic events, but a small, isolated population will always be more prolific of new species than a large, dispersed one if only because the trend of local selective pressure will consistent across the whole population. It is hard to imagine the same selective pressures acting in a sufficiently consistent manner across a very large geographic area.
Of course, just because something is hard to imagine doesn't mean it didn't occur.
Remember, you only find what you are looking for.
Nonsense. Scientists find stuff all the time that we weren't looking for. Sometimes we ignore it if our preconceived ideas conflict with it, but we do so at our peril, because someone else will notice it, publish it, win the Nobel and get all the hot chicks.
--Tom
You laugh, but it's fairly well-established that ~10% of babies are fathered by someone other than their mother's socially pair-bonded mate.
Here is an extensive summary of studies. As the summary suggests, rates of misattributed paternity vary widely, from about 1% in some areas to over 20% in others, mostly depending on social/economic status. However, the fact is, most of us are almost certain to have some interlopers in our heritage--we are all mongrels under the skin!
--Tom
Some people overseas may have an interest in not destroying their kits...
And that is different from some people in the U.S. how? Google on anthrax if you don't know why I'm asking.
--Tom
Humans are just the tool that our genes use to make more genes.
If so, they've chosen a fantastically inefficient way to do it, haven't they? You could have a dozen kids, and still lose 0.024% of your genes forever. If you have two kids, a full 1/4 of your genes would never be transmitted to posterity.
Sexual reproduction is a good trade-off for an organism, but a terrible deal for the organism's genes.
--Tom
Weird how that hasn't been a big problem for micro-organisms, corals and other multi-cellular and polyp creatures that don't experience death by old age.
--Tom
And you wonder where famine comes from.
We know where famine comes from. In the past century it came exclusively from governments using control of the food supply as a weapon. The famine in Darfur is the most recent example of this.
The problem of landless small farmers in the developing world is real. So is the problem of GM crops that get loose. And Monsanto is pretty much the incarnation of evil. But any account of the looming GM disaster that leaves the deep complicity of governments out of the picture is radically incomplete.
--Tom
I don't get why people keep saying it will "never" work. It's a hard problem, but I'm aware of no physical laws that are violated by BMD.
People say BMD will never work because they are aware that in the face of an even moderately successful BMD system terrorists and rogue states (against whom the current BMD system is targeted) will opt to deliver nuclear weapons to American cities by stealth.
The canonical stealth method of delivery involves hiding nuclear bombs in bales of marijuana. Drug interdiction doesn't violate any physical laws either, but not all problems are physics problems.
--Tom
The event horizon is a singularity in the co-ordinate system of distant observers. It is correct to say that Planck-scale effects won't remove the event horizon in the sense that we still won't be able to observe much inside it. But they will remove the singularity of the event horizon, as they will also remove the singularity of the infinite density at the centre (the singularity you say black holes "contain").
I'm using "singularity" in the mathematical sense, not the physical sense, which is reasonable because physically there are no singularities (we hope.) The proposed model includes an event horizon, but not the (mathematical) singularity at the event horizon. It does this on a scale much larger than the Planck scale, and so will have much larger observable effects on the physics of the horizon.
If you choose to define "black hole" in terms of an event horizon, then the new theory is just a theory of black holes. But certainly many people make a point of identifying black holes with singularities, which means if you get rid of the singularities, you get rid of the black holes.
--Tom
The problem with black holes is that they are, by definition, singularities. Unadulterated GR says that matter becomes infinitely dense, that the event horizon is infinitely sharp, etc.
This isn't very satisfactory, and we've known for a long time that something interesting must happen to smooth out these infinities at the Planck scale (something to the tune of 10^-33 cm). In this limited sense, we've known all along that "strict" black holes don't exist: that is, the pure, mathematical singularities that GR predicts must be smoothed out by quantum effects at very short scales.
In keeping with the sloppy thinking that makes physics the Queen of the Sciences (IAAP, as it happens) we've decided that those Planck-scale effects don't really count, and implicitly modified our concept of "Black Hole" to accomodate them.
What this guy is playing with is the idea that something interesting happens on much larger scales. In this case, although there is still something like an event horizon, it is no longer a singularity in the space-time co-ordinates of distant observers, but rather a phase transition in the quantum-mechanical vaccuum. He is proposing a macroscopic quantum mechanism for smoothing out the singularity.
This is a nice move for two reasons: the study of quantum critical behavior has a variety of analogues such as superfluids that can be studied in the lab; and there are physical phenomena that he predicts which may explain a variety of otherwise problematic observations. These are: high-energy positrons from the centre of our galaxy (where there is a 10^6 solar mass dense object); gamma-ray bursts; cosmological dark matter.
Overall, this is a nice, plausible, interesting approach to a serious problem.
--Tom
For what I shall tell concerning them is not an Hypothesis but most rigid consequence, not conjectured by barely inferring 'tis thus because not otherwise or because it satisfies all phaenomena (the Philosophers universal Topick,) but evinced by the mediation of experiments concluding directly and without any suspicion of doubt. --Newton (in a letter to Oldenburg, regarding the colours of light in the Opticks)
While hypothesis and refutation is a useful tool in science, it is not the only tool, and particularly when one is engaged in the creation of new concepts we can go considerably beyond it.
--Tom
Protein biomarker analysis is still very much in its infancy, and while the results to date have been promising, the sample sizes have been small and the data quality frequently problematic.
For example, early protein biomarker datasets for ovarian cancer detection were a catalog of artefacts, and even today many analyses are run on datasets that have not had proper feature detection done on them. This results in the discovery of "patterns" that involve structures that are clearly non-physical (for example, peaks that are much narrower than the resolution of the apparatus.)
There are also fundamental difficulties with high false discovery rates when running pattern recognition software on these data. Statistically speaking, the question you are asking is: what are the odds that I can find N channels that a classification algorithm can use to distinguish class A from class ~A? When you have thousands of channels, and N is somewhere between 2 and 10, and you have only a few dozen samples, the a priori probability of being able to find a classifier is essentially unity.
So while I think this whole approach to disease is interesting, it is very likely that one could achieve similar results to the ones reported in this abstract even if the data were pure noise.
--Tom
One of the things that created the Y2K problem was the unexpected longevity of code. No one coding in the 80's seriously believed that their code would still be used as the basis for released applications in the late '90's.
On the basis of things like this we should expect digital content to remain of interest considerably longer than we might currently expect. There are other reasons to believe this: I own a number of books that are more than 40 years old, and some of them are not only useful but still quite current (Heitler's Quantum Theory of Radiation, for example.) And I'm reading a novel at the moment that was printed over 100 years ago.
The nice thing about paper is that if you leave it alone under reasonable conditions it persists pretty well. If digital media can't do the same, then there is a significant hidden cost involved in using them. For large organizations this cost is just one component of the usual process of archival data management, but for the average person it is something new.
--Tom
It isn't the universe that has to be elegant, but our theory of it. The reason why is that we aren't very smart, and theories with fewer free parameters are a lot easier for us to understand.
--Tom