Domain: sciamdigital.com
Stories and comments across the archive that link to sciamdigital.com.
Comments · 43
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Learning how to fart
Bullies are cowards. All of them.
Actually studies have shown the complete opposite (I read it on paper). It used to be fashionable to attribute this kind of behavior to low self esteem, until someone actually bothered to investigate this, and found that bullies actually tend to have unrealistically high self esteem and tend to be more bold and impulsive than average.
From this, the logical next step would be to subject a bully to so much abuse that his self esteem is shattered and see if this changes their behavior. This would obviously be immoral.
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Re:I could do that...Impressive, but I'm not referring to aluminum hummer design. I'm talking about aluminum beer can design.
The link is to an abstract only page, but the abstract conveys my point.
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more more
http://www.sciamdigital.com/index.cfm?fa=Products.ViewIssuePreview&ARTICLEID_CHAR=253EE806-FA7B-4693-8F1D-BDBB1E68AAF is an article i wrote many moons ago for scientific american on these optical telegraph networks more info still, in this book: http://spinroot.com/gerard/hist.html
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Re:Uhm...
I remember him from this article (had to buy it on paper, no internet that I was aware of then) http://www.sciamdigital.com/index.cfm?fa=Products
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Re:Diesel now has much less sulphur and particulat
Read the March Scientific American article on diesel engines. Also, keep in mind two things:
1) Diesel fuel has more energy than gasoline, so it requires less of it
2) The big problem is C02 emissions. If we can become carbon neutral with BioDiesel, then the other issues can be dealt with. -
Strawmen...
While, i will grant that global warming is just a "theory," claiming that this is a valid argument for not trying to develop another theory is quite simmiliar to people who claim that evolution is just theory a and therefore we should neither continue teaching it nor researching speciation, the fossil record, and genomics - without the theory of evolution, those that study these aspects of earth's biology would have nothing to theorize about. This line of argument is neither helpful nor meritricious.
The evidence pointing toward episodic global warming is very compelling, especially when seen in the hockey stick graph, for those of us who understand visual representations more than verbiage. Global warming, though just a theory, is pretty well established, where the question really lies, and why this atmosphric blanket might need to be further researched is, how much impact are humans really having on the climate? Granted, there is evidence that humans have already managed to divert a global ice age, so it is unlikely that we aren't completely benign, this does not mean that the current warming has as much to do with us as we would like to think. The earth has natural cycles of warming and cooling, so, although I agree that we should cut down emissions, and try to be a little less environmentally impactful, we also need to figure out wether this current relative warmth is due to our noxious by-products, or just part of a natural cycle that has existed for billions of years. On the one hand, humans are highly destructive creatures and should be aware of the harm they cause Gaia, on the other, we are also too proud and need to stop internalizing our locus of control to the point that we loose our pragmatic perception of what is really going on in the world. -
So What's New?
Wasn't this in Scientific American, like, two years ago? What has changed? http://www.sciamdigital.com/index.cfm?fa=Products
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Scientific American article
This month's edition of Scientific American had a good article on Ray Tracing. Basically, how it can be more feasible with the faster/better hardware we have today. The article is available here, but unfortunately, you have to pay for it. The article focused on new software and hardware techniques for Ray Tracing being developed at Intel. They say that Ray Tracing is "poised to replace raster graphics" because it "scales well with hyper threading and multi-processor configurations.". Also the "cache hierarchy associated with CPU's is very effective at managing the external memory bandwidth requirements". With multicore processors entering the mainstream, they may have a point.
I wish I could remember more from the article, but I read it some time ago. -
Re:It's good to see they're making progress
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Re:ReGenesis again?
While I was browsing through the rest of the comments, I decided to not be so lazy and look up the date of the SA article on this topic. It was in the 01/01/05 issue and you can download it [for a price] here if that's your "thang."
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Since I keep up on this....
I had h. pylori, was treated for it, and had an ulcer 6 months AFTER I was treated.
http://www.sciamdigital.com/browse.cfm?sequencenam eCHAR=item2&methodnameCHAR=resource_getitembrowse& interfacenameCHAR=browse.cfm&ISSUEID_CHAR=4A323396 -2B35-221B-6CAC6761F49DBCB0&ARTICLEID_CHAR=4A41516 6-2B35-221B-66FE5BDD02F9CA34&sc=I100322
This is a protection element, and is not the cause of ulcers, but they are related. -
Dupe from Scientific American 1995
I'm sureI have read the same article several years ago,I cannot remember were, maybe on Scientific American or such. After a search on sciam.com I have found this dated January 1995, more than ten years ago. Are we reading the older news ever posted on slashdot?
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old story
This scenario is an almost exact ripoff of a Jan 1995 *Scientific American* article [sciam.com]
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Re:Doom and Gloom
Carbon Dioxide is not the only greenhouse gas.
There is a lot of water vapor in the air, and it is a greenhouse gas. The warmer the climate, the more water evaporates into the air, the more heat is trapped, and it gets even warmer, at least to a point where cloud cover reflects light.
Methane is a much more effective greenhouse gas than CO2. The advent of civilization and agriculture roughly around 6,000+/- years ago significantly increased the amount of methane, though there are a lot of natural sources of that as well.
Even more effective greenhouse gases include refrigerants and other manmade chemicals not common until the industrial revolution. There are no siginificant natural sources of R-22, R-11, R-12, etc. and several other manmade chemicals.
Some particulate pollutants, manmade and natural, reflect sunlight and cool the earth, some reflect sunlight and cool the earth.
There is much uncertainty in the particular changes in climate that may hit a particular area, but there is no question that the models back up the general trend - it is getting hotter and human activity is a significant contributing factor to that trend.
http://www.eia.doe.gov/oiaf/1605/ggccebro/chapter1 .html
http://en.wikipedia.org/wiki/Greenhouse_gas
http://www.sciamdigital.com/browse.cfm?ITEMIDCHAR= F9374686-2B35-221B-635B1D2A02A8B6D5&methodnameCHAR =&interfacenameCHAR=browse.cfm&ISSUEID_CHAR=F9214C AB-2B35-221B-641728E52ACE63F4&ArticleTypeSubInclud e_BIT=0&sequencenameCHAR=itemP -
Re:Can I get a link please?
My point was that there seems to be no math, measurements or any scientific evidence demonstrated on the "Electric Universe" web site linked to above.
There is quite a bit of evidence for the current astrophysical theories, at least the ones that are considered more than just speculation. Go through the back issues of Scientific American for a good resource on the latest state of science, for one:
http://www.sciamdigital.com/browse.cfm?sequencenam eCHAR=item2&methodnameCHAR=resource_getitembrowse& interfacenameCHAR=browse.cfm&ISSUEID_CHAR=376F2051 -382E-4520-92AE-30C33349E8E&ARTICLEID_CHAR=6793D8D 9-7868-4714-B18D-2FBCDBAAB57&sc=I100322
Math predicting something in the physical universe, which is then measured to match the theory to several decimal places, that's called science, and some of us find it is a big deal.
Real Science has the potential to protect us from a very dangerous universe. Science predicted the devastation in New Orleans, but politicians decided they knew better.
This was reported by several media sources, here's one for reference:
http://www3.nationalgeographic.com/ngm/0410/featur e5/index.html?fs=www7.nationalgeographic.com
You go ahead and be happy, I'd prefer that scientists keep studying this place and warn me when they predict trouble is on the way.
It's not helpful having crooks selling junk science to clutter up the discussion. -
Scientific American, October 2001http://www.sciamdigital.com/browse.cfm?sequencena
m eCHAR=item2&methodnameCHAR=resource_getitembrowse& interfacenameCHAR=browse.cfm&ISSUEID_CHAR=1353CDCA -AF4D-4B1D-85F4-5B68F2A7E17&ARTICLEID_CHAR=D58B96E 1-60BC-4C0F-BCE2-8C9B8A05275&sc=I100322"New Orleans is a disaster waiting to happen. The city lies below sea level, in a bowl bordered by levees that fend off Lake Pontchartrain to the north and the Mississippi River to the south and west...
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Re:Geomagnetic reversal happens, but aliens don't
Actually the current thinking is that we will probably not, in fact, be fucked. The Earth's field will flip but is not thought that it will disappear in the interim. It is currently thought (using geodynamo simulations on supercomputers and giant rotating spheres of hot liquid sodium in the laboratory) that the field weaken and become severely contorted but will not completely vanish. The recent article in SciAm "Probing the Geodynamo" explains things very nicely.
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SCIAM Article
There was an article in the June 2005 about suspended animation. Link, just intro The method of injecting a saline solution was discussed, and the article even mentions experiments with dogs. Basically, the saline solution removes all oxygen, which puts the cells into hibernation. At an intermediate level of oxygen cells will die because they aren't completely in hibernation, and thus try to use oxygen they can't get. However, above or below a certain point they are viable and will hibernate(low) or metabolize normally(normal).
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Re:well...
actually, it was Scientific American, and it was written by Mark Roth, the lead investigator in the hydrogen sulfide experiment.
Article Summary -
Re:Here we go again...Although I would have denied it a couple of years ago -- at least I would have said there's not enough evidence -- global warming does appear real. However, it may not be as bad as it is put out to be. In the March 2005 Scientific American there was an article suggesting that except for global warming we would be clearly headed into the next ice age. Go to your library if you don't have the March issue, otherwise you're forced to buy it online from SciAm, but here's part of the article's summary:
New evidence suggests that concentrations of CO2 started rising about 8,000 years ago, even though natural trends indicate they should have been dropping. Some 3,000 years later the same thing happened to methane, another heat-trapping gas. The consequences of these surprising rises have been profound. Without them, current temperatures in northern parts of North America and Europe would be cooler by three to four degrees Celsius--enough to make agriculture difficult. In addition, an incipient ice age--marked by the appearance of small ice caps--would probably have begun several thousand years ago in parts of northeastern Canada. Instead the earth's climate has remained relatively warm and stable in recent millennia.
So, all that CO2 in the atmosphere may be saving our butts from getting frozen off.
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Scientific American, and his web site
In the 90s, he had this column in Scientific American that was really informative and entertaining. It also sought connection between people and events that brought us what we have in terms of inventions, technology,
...etc.Here are previews of some examples:
Here also has an informative web site Knowledge Web.
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max size
There was a scientific american article some years back about Murphy's law. The article was trying to prove that Murphy's law was a universal constant and was using the fact that bread always landed butter side down as the start of its proof. in order to prove this, the writers went into a great deal of detail about rotational speed of toast falling off a table, the range of table heights that were required for a 180 degree turn of the bread, and the beings that might sit at such a table.
The end result of the article was a proof that the maximum height of a bipedal being, (one that would not crack its skull and die every time it fell over,) was about 9'8", and such a being would use a table that was of a height that fit into the previously described range, therefore Murphy's law, (as it applied to bread landing butter side down,) was in fact a universal truth.
I think the article was printed around '95 so you have to buy the archive... http://www.sciamdigital.com/browse.cfm?ITEMIDCHAR= A3B20D65-8339-4260-A5D1-4E6E083116A&methodnameCHAR =&interfacenameCHAR=browse.cfm&ISSUEID_CHAR=C2A9E0 84-7CAA-4ABC-9BAE-BF9C44829FB&ArticleTypeSubInclud e_BIT=0&sequencenameCHAR=itemP
(for those who read this far, it wasa joke...) -
Re:An idea
Wow, I wasn't going to get into this, but this post...
1. Scientists never come to "unanimous concensus" on anything, that's not how science works. That's how Dogma works. Science is the search of truth through experimentation and observation, you can't find truth if you're judgements are clouded by preconception. There is always someone somewhere trying to disprove even the most basic theores. That said, it's almost impossible to find a respected member of the community who denys Global Warming anymore, although there are no shortage of crackpots (guys who do no actual science, just make up their own stuff and spout it off in front of national commitees. People who have maybe one peer reviewed article published ever and suddenly become experts in everything, etc...).
2. We've actually got a LOT of data. Ice cores from the artic for instance provide a good indication of the percentage of greenhouse gasses in the atmosphere. There was a great article in Scientific American charting the progress of greenhouse gasses over the past 8,000 years via this method.
3. The Sun's Cycles are actually fairly well understood at this point.
4. Who is running trends against a 10 year forecast? Local variation is hard to filter out as is pure chaos at that level. That's why it most everybody has gone to longer term data sources to analyize the trends. There has been some talk about rapid climate change, but as far as I know those claims are still treated with scepticism among the community at large. They'll need stronger evidence to convince the majority of scientists.
5. Global climate change isn't like predicting the amount of rain you are going to get next Tuesday. Whereas local effects are chaotic and difficult to pin down, long term trends tend to be very predictable although hard to observe (especially if they are subtle). However, this is not a new field, and the general proponderance of evidence has shifted most scientists into the "yep, global warming is real" camp. One gets the feeling that the ones who are left in the "not enough evidence" camp at this point have some other agenda and will never have enough evidence, even if it's 80C in Toranto.
6. Remember what I said about subtle effects? They require subtle solutions.
By "recycling someone else's data" do you really mean "doing your homework?" Are you not allowed to talk about this unless you've personally dug ice cores out of the artic or examined ancient peat moss? I know the "global warming is a myth" guys hate to drag actual scientific discoveries and observations into the disussion (they always attack the evidence, looking for the smallest hint of uncertanty, which all observed data has because nobody is omniscient).
Here's a hint, if your argument boils down to: "You can't say anything because there is a chance, no matter how slight, that you are wrong." Then you have missed the point. There is ALWAYS the chance that you are wrong. Any theory can be disproven. The best you can do is say "This is the most likely conclusion based on all of the known data." Even though there is a massive body of evidence supporting your claim and nothing opposing it, there is always a chance that someone somewhere will disprove your claim. Yes, Global Warming COULD be a myth perpetuated by mountains of bad testing procedures or flawed premesis, but the chances of that happening are extremely slim at this point. In much the same way, the Sun might be made out of Cream Cheese and all of our data might be in error. -
This isn't new.
This isn't new. Readers of Scientific American will recall a special edition which proposed warming Mars with greenhouse gases *years* ago. Ah, here we go. From 1999: The Future of Space Exploration. This is not new by any stretch of the imagination.
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How long does R&D take?You'd think that they could innovate with their $65 billion in cash. Instead, we get a grand total of - not one, not two - but THREE color schemes for Windows XP. It is arrogance like this that will eventually displace Microsoft. Not that color schemes matter, but the company hasn't come up with anything original in a long time. This is just a good example.
And they spend billions on R&D every year. It is like there is some law that prevents them from coming up with something both useful and non-evil. I have about a hundred ideas that they could use right now.
In the last year, there was an article in Scientific American (I think it was the June issue ) that described Microsoft's R&D department. Essentially, they are buying up some of the best people out there to innovate for them. Of course, the next question is always "What have they produced?" I don't know. Maybe they have produced something, maybe they are getting ready to, who knows? They might just be storing up patents. They have the money and capabilities to innovate, but I think it may take a while to come to fruition. -
Re:Only at the poles for half the year(getting OT)
Actually, fuel cells can have better well-to-wheel efficiencies than the standard gasoline internal combustion engine. In the May 2004 edition of Scientific American, this article http://www.sciamdigital.com/browse.cfm?sequencena
m eCHAR=item2&methodnameCHAR=resource_getitembrowse& interfacenameCHAR=browse.cfm&ISSUEID_CHAR=CB826BAE -2B35-221B-6E2587F29CF2C88A&ARTICLEID_CHAR=CB9BE5E 6-2B35-221B-6F2461DEF9B52B9C&sc=I100322 shows that a fuel cell powered by steam reforming has a total efficiency of over 20%, while an ICE has an total efficiency of about 10%. -
Re:No lemon law in MinnesotaThe real question is whether the number of possible distances between two physical objects can be counted. Can space be sliced into infinitely thin partitions? Much of our model of the universe assumes that it can, but these are the same pieces that keep causing us problems.
There was an interesting SciAm article a few issues back titled "Atoms of Space and Time" that was pretty interesting, if you get a chance to read it. There are some interesting models of the universe that describe space and time as discrete. One giant quantum computer, in a way.
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Re:Stiry of Atlantis was an allegory; it was not r
Also, Atlantis is an allegory to show the futility of huge military buildup. Ref: Sciam, 10/04
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Re:tell the entire story of our evolution over timI'm glad that you're willing to accept criticism of your ideas. A lot of people have a fear of having to reevaluate their beliefs.
From reading your paper, I would have to say that I have a very different perspective from yours. Maybe you will find some of my observations useful.
#1 - OK, to start off with you're wandering way outside the bounds of evolution as it applies to living organisms. If we truly had an all encompassing "theory of everything" then we might be able to describe the development of the universe in terms of evolutionary processes, but right now all we can do is speculate.
#2 - Regarding your observation that we don't have an explanation for the "origination of the origination", I think that there are two ways of looking at it. First off, just because science does not yet have an explanation of what caused the big bang does not mean that it cannot be explained. The goal of science is not to provide absolute truth, but to provide the *best* explanation that we can come up with. Secondly, even if you explained what was "beyond" the big bang, you would have to explain what's beyond that, right? And then what's beyond that? In other words, no matter how good your description of the universe is, someone can always ask, "well what's beyond the boundary?" The answer is that whatever is beyond the boundary has no scientific explanation. If something is so intangible that we can't describe it in any way, then it's not something that we can think about in a logical way.
#3 - Yes. I'm not sure why you bring this up. Not only are our measuring devices not perfectly accurate, but our best theories (relativity and quantum mechanics) are not complete. Nobody claims that we have a perfect description of the universe.
#5 - Sexual reproduction is actually very useful. By combining the genes of two fit individuals, you are more likely to get an even fitter offspring that if you simply mutated the genes of the two parents independently. This is a technique that has proved useful when using evolutionary processes to solve problems. this was a really interesting article about using evolution to "invent" new hardware circuits. Unfortunately you have to have a subscription to read it, but I read the print version when it came out. Combining "genes" from fit "genomes" was one of the techniques that they used. Very interesting article. As far as the usefulness of the "pleasure" aspect, this is a pretty good way to encourage individuals to produce offspring. It works differently with different species, as different species have evolved different strategies for promoting their genes and thereby continuing to exist.
#6 I'm afraid you don't understand the big bang. Matter didn't "explode" outward from a central point. Space *itself* expanded out from a central point. The common analogy is to take a balloon and draw a bunch of dots on it. The balloon is spacetime and the dots are matter. Now blow up the balloon. The dots get farther apart not because they're moving through spacetime, but because spacetime itself is expanding. I can't give a thorough explanation here, but you might want to read up on it.
#8 - The fact that we were wrong about the amount of dust on the moon does not "prove" anything except the fact that one or more of our assumptions were wrong. Imagine an analagous scenario. I have an equation that predicts your age based on your height. I know your height, and so I use it to predict your age. Turns out, you're actually older than what I predicted. Does this mean that I was wrong about your height? Possibly, but it's just as likely that my equation was wrong. Science is wrong about things all the time. Constantly. In fact, science is a way of studying the universe tha
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Re:I'll push your buttons.
I'm sick of people like you, who think their way is the right way. I leave people like you alone to do whatever they wish to do, so long as it doesn't affect me. Why the hell can't you provide the same courtsey?
First off, I agree that if somebody is actually watching the TV, then turning it off is rude. I wouldn't do it. But a lot of times, TVs are just left on in public and semi-public spaces when nobody cares. Or even worse, when everybody present actively wants them off.
And we are gradually realizing that television, although sometimes enjoyable, is not entirely benign. Scientific American published a fine article on the addictive potential of TV. It seems that TV, especially programs made with modern editing styles, trigger hardwired behavior to look at motion. It also appears to cause Attention Deficit Disorder in children. And everybody knows how distracting it can be, how it gets in the way of conversation.
So to me, TV in public and semi-public spaces seems pretty analogous to smoking. Some people enjoy it, but the common mode of use means it bothers others. The big difference is that smoking requires an active smoker to do something every few minutes, whereas the TV runs until somebody actively turns it off.
The question, then, is how to negotiate the use of common space. Everybody just wants to be let alone to do their thing, but some people feel that involves having a TV on, and others feel that involves having the TV off. Personally, I think the search for a simple, universal answer is a waste of time. As with smoking, I think the important thing is that people find an answer together, one that everybody can live with. -
Re:Democracy..I don't know if I agree with your politics, but we're both fighting the same uphill battle - I'm consistently forced to vote for someone other than the candidate I want to vote for. Why? Because of the way our electoral system works. When it's winner take all, voting for someone who has little chance of winning means sacrificing your vote.
The only solution to this problem is electoral reform. Instant runoff voting or something. No, I'm not an expert on electoral systems and the tradeoffs between them, but experts do exist. I suggest that we, as a democracy, use the information gathered by these experts to refine our system a bit.
There was a great article comparing different systems in a recent Scientific American, but unfortunately it's not available electronically without paying for it. I read the print version and it looks like we have a lot of options - I suggest we try them out. The only reasonable place to start is at a local level, so if you're really concerned about the issue then push for change in your local government's voting system!
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Re:Obligatory Futurama reference ...
Indeed. For additional digression of memory/perception from reality check out the September 1997 issue of Scientific American. It contains an article about false memories. I think that's the article I'm remembering, but I can't be sure. It's the most promising in my quick search results.
I'm also reminded of the Hindu concept of an illusory reality, the veils of Maya.
In any case, it's an interesting puzzle to tumble over in one's head.
~~Galen~~
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no-pulse artificial hearts are commonIt's not the "no-puse" part of this LVAD, but the no-bearing part that's interesting. This one is more fault tolerant. Artificial hearts that produce no pulse are very common. Mechanically it's harder to make an artificial heart that provides a pulse than not.
I remember reading about a condition in a heart-lung patient called "pumphead", and found a partial article online. So there may be something useful to the body that a pulse provides. Some capillaries may have come to mechanically rely on the high and low pressures provided by a pulse. I'm reminded of how tides are useful to life on ocean shores like certain sea anenamies, or gremlins or turtles that deposit their eggs during the highest tide of the month.
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If You Have a Real Library Nearby ...
I'm truly ashamed for people who think that hydrogen fuel cells will solve all of the world's fossil fuel problems. Sure, hydrogen fuel cells will make for extremely low exhaust cars, longer laptop battery life, etc, but they won't solve the fossil fuel crisis.
Good article in Scientific American either this month or last. Addresses the total energy costs of fuel cells and a "hydrogen economy" in general.
I guess it was May. -
IIRC
IIRC, Scientific American had an article a few years back about how to make a stable kite cam with a disposible (read: invincible) camera. Here's a link, but it costs $$$.
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Re:My first question
The dark energy refered to is unusual because it implies a kind of antigravity. It isn't drawn into play to account for the fact that the universe is expanding, but rather to explain the recent observations that indicate that the rate of expansion is increasing.
It is related to Einstein's cosmological constant which Einstein regretted introducing because it was kind of a kludge to account for a supposed static universe.
Apparently there are cosmologists today who still regard it as a bit of a kludge, making the cosmological model convoluted like Ptolemy's model of the solar system. There was a recent Scientific American article that discussed this, but only a summary is available online.
Maybe you were confusing it with dark matter?
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scientific american
I read an article in Discover or Scientifc American (can't remember which!) recently detailing the shift to alternative fuels. Not only is it a challenge to develop applicable technologies that are economical for end users, an even greater challenge will be to develop the infrastructure necessary to support these vehicles. We take for granted that one can stop at a gas station and fill up. If one we're driving a propane-powered vehicle, one would require an appropriate filling station.
It was probably this article on pages 68-73 of the May 2004 issue of scientific american. It is actually an article on hydrogen cars and their infrastructure problems. Nice article, with better comparisons than most, but the hydrogen-specific complaints are already well known.
The propane infrastructure is a whole different topic. Propane can currently be purchased lots of places, and Propane cars are already common. There are even a few propane dragsters (10:34 sec 1/4 mile @ 127.10mph)
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article details
This is an excellent point that was covered by Scientific American recently. I am not sure about the statistics though.
The article compared traditional vehicles with electric vehicles (adding in what was necessary to recharge them). The findings were pretty awakening.
Yup. Pages 68-73 of the May 2004 issue. The excerpt/teaser for the article is on their website here. It is actually an article on hydrogen cars, but electricity is mentioned. It doesn't discuss battery-electric cars, but does discuss hydrogen fuel cells powered by hydrogen from electrolysis. One illustration in the article compares the component and total efficiencies for 11 different possible drivetrain/fuel combos. This chart shows gasoline internal comustion engine efficiency as[*]:
Fuel Chain Efficiency = 80%
Vehicle Efficiency = 18%
Total Efficiency = 14.4%
If hydrogen comes from grid electricity[**], This same chart shows hydrogen fuel cell efficiency as:
Fuel Chain Efficiency = 22%
Vehicle Efficiency = 38%
Total Efficiency = 8.4%%
It also has a chart for emmissions. That chart says that total emmissions (fuel chain + vehical) greenouse gas emmissions for a gasoline ICE are around 380 grams/mile[+]. It says total emmissions of greenhouse gasses for a grid electric -> hydrogen fuel cell car are 430 grams/mile.
The electrolysis process should not produce greenhouse gasses, so those figures should be a reasonable reflection of electric power generation for electric vehicles, too.
Of course, electric powerplants operate below peak capacity most of the time. Electric vehical advocates point to the negligible amount of energy required by the addition of a couple hundred battery chargers to the grid of a major city.
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* - this chart has efficiency on the Y axis, with 100% at the top, and 0% at the bottom. The only marks on the Y axis are for 20%, 40%, 60%, and 80%. That makes exact numbers difficult to obtain; i.e. these are best guesses based on the a bar graph without nicely marked units. There is no question that the graph shows gasoline ICEs as being more efficient than grid electric->hydrogen fuel cells
** - This assumes the hydrogen source is electricity from a local grid. Most local grids in the USA are powered by fossil fuel.
+ - don't blame me. I'm not the moron who chose to mix metric and english units of measurment. -
Re:Remember Lady Ada
There was published in "Scientific American" magazine a while back an article about the computer program that Lady Ada wrote, including bugs. See this brief description.
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Dark matter may not exist
The assumption that "dark matter" exists is a common one based on (some of) the observations of the universe. Dark matter does not explain the increased rate of expansion of the universe at great distances. This requires another assumption - "dark energy" (or a positive "cosmological constant").
There are versions of M-theory which do not require one or both of these. There is also a theory, as yet unpublished (since it upsets physics journal editors), which eliminates the "clock hypothesis" and accounts for inflation and accelerated expansion. (One has to be careful to take each new (and old) theory in physics with a big grain of salt.)
Just as the biological community "sold" the human genome project as THE ANSWER (one gene = one protein) and is trying to sell the protein folding problem as the NEW ANSWER (and it is an important problem), the (majority of) the (astro)physics community is trying to sell "dark" (matter or energy). "Dark" may well exist. I believe that it is important to allow a variety of views in the physics community to be heard (i.e. published) and let scientists design experiments to test various hypotheses. The "popular" theory may (or may not) correspond to observations. -
Re:not HIV -- ebola
Gibbs, W. Wayt. (2003). The Unseen Genome: Beyond DNA. Scientific American, 289(6), 106-113. (December 2003 issue)
Teaser line:
DNA was once considered the sole repository of heritable information. But biologists are starting to decipher a separate, much more malleable layer of information encoded within the chromosomes. Genetics, make way for epigenetics
Four paragraphs from the first page:
A genome, the sum of heritable information that is held in the chromosomes and that governs how an organism develops, is not a static text passed from one generation to the next. Rather a genome is a biochemical machine of awesome complexity. Like all machines, it operates in three-dimensional space, and it has distinct and dynamic interacting parts.
Protein-coding genes make up just one of those parts--and often a small one at that, accounting for less than 2 percent of the total DNA in each human cell. But for the better part of five decades, those genes were enshrined by the central dogma of molecular biology as the repository of heritable traits. Hence the notion of the genome as a blueprint.
As far back as the 1960s, experimenters had uncovered important information hiding elsewhere in the chromosomes. Some was tucked among the "noncoding" DNA, and some lay outside the DNA sequence altogether. The tools of genetic engineering worked best on conventional genes and proteins, however, so scientists looked hardest where the light was brightest. In recent years, geneticists have been exploring the less visible parts of the genome more thoroughly, in search of explanations for anomalies that contradict the central dogma: illnesses that run in families but pop up unpredictably, even differing among identical twins; genes that switch on or off in cancers yet harbor no mutations; clones that usually die in the womb. They have found that these second and third layers of information, distinct from the protein-coding genes, connect in surprisingly deep and potent ways to inheritance, development and disease. In the November issue of Scientific American, "The Unseen Genome: Gems among the Junk" described those connections for the second layer, which consists of myriad "RNA only" genes sequestered within vast stretches of noncoding DNA. Science had dismissed such DNA as the useless detritus of evolution, because no proteins are made from it. But it turns out that these unconventional genes do give rise to active RNAs, through which they profoundly alter the behavior of normal genes. Malfunctions in RNA-only genes can inflict severe damage.
The third part to the genomic machine, as fascinating as active RNA genes and probably even more important, is the "epigenetic" layer of information stored in the proteins and chemicals that surround and stick to DNA. Epigenetic marks are so named because they can dramatically affect the health and characteristics of an organism--some are even passed from parent to child--yet they do not alter the underlying DNA sequence.
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Re:Standards must be agreed on firstThe Tyranny of Choice?: (Registration required, probably subscription too)
Americans today choose among more options in more parts of life than has ever been possible before. To an extent, the opportunity to choose enhances our lives. It is only logical to think that if some choice is good, more is better; people who care about having infinite options will benefit from them, and those who do not can always just ignore the 273 versions of cereal they have never tried. Yet recent research strongly suggests that, psychologically, this assumption is wrong. Although some choice is undoubtedly better than none, more is not always better than less.
There was a /. article about it recently.
Anyway: Too little choice is depressing; too much choice is depressing. There is a sweetspot where positive emotions peaks, but there are no concrete numbers. -
Re:Umm...
Exactly. This doesn't seem to take into account the possible self-repair that the brain performs. It could very well be that any damage inflicted on the brain via magnetic fields would be repaired during sleep.
It's been reported that sleep repairs the normal daily damage done on the brain from free radicals (different stages of sleep repairing different parts of the brain), and I can't see why this wouldn't carry over to magnetic damage. Is there a neurosurgeon in the house?