SkepticLance

I have read a bit further in the book, and it is clear that the author has an abysmal lack of knowledge of the science he writes about. For example : He writes about a habitat in space, in which the designers want to introduce gravity. They do it by blowing air down to hold people to the floor!!! Obviously has not heard about pseudogravity from spinning.

I read in a science article a couple of years back, that if we added air to the moon, its gravity would hold it for about one million years before the solar wind blew it off into space. The moon seems a better bet to me for those kinds of shenanigans. One sixth gravity should be OK, and it is much closer than Jupiter's moons.

I am currently reading a scifi book called Gradisil. Intersting theme - it is about a community of people who live in space habitats in Earth orbit. However, the author just introduced an idea I think would not work, and I would like to hear what others think the implication is. The author suggests a person living in one of the orbiting habitats lowers a 50 km long pipe to the Earth's atmosphere to pump air up. My immediate thought is that this will act as a brake, and slow the movement of the habitat, hence causing it to move into lower and lower orbit, till it finally falls to Earth, burning up. I also wonder about the difficulty in actually pumping air up a 50 km long thin tube.

The answer to the original question, from a consciousness viewpoint, is yes. It is like asking if a darkness is like the darkness that happened before the light was turned on, or the darkness after the light was turned off. The answer is that dark is dark, and it does not matter which dark. They are the same. Before fertilisation, there is no consciousness. After death there is no consciousness (excluding general religious dogmas) and both non consciousnesses are the same.

Sisyphus We need to compare apples with apples. Somalia suffers from warlordism, and unceasing conflict. Afghanistan is essentially tribal with lots of inter-tribal conflict. Hong Kong was a single community with no immediate hostile neighbours, at the time. China wanted to re-absorb it, but was prepared to refrain due to its treaty obligations. Anyway, China had lots else on its plate at the time. Obviously, for some form of laissez faire economics to work, we need to have it operate within an environment of peace and political stability. We need to have a balance so that it is not simply anarchy. We need to have some rules, well policed, to stop its relative freedom from becoming a vehicle for exploitation. Hong Kong, under Britain, achieved those conditions.

To Bear My own personal view always revolves around the need for balance. The Hong Kong example serves to show the potential of ordinary people when they are given a chance. The fact that the colony thrived under a liberal and understanding colonial government shows that freedom and limited restrictions is good for people. The example is even more extreme if you take into account the millions of refugees from China that fled to Hong Kong and had to be cared for. However, they tended to become contributors, not parasites. What is the balance here? Well, maximum freedom balanced by such restrictions needed to prevent the nasty bastards from exploiting everyone else. It appears that the British colonial government managed to get it pretty much right. Business also needs maximum freedom with enough restrictions to prevent cheating. This is not quite 'laissez faire', but can approach it. What needs to be avoided is excess bureaucracy, and the associated massive compliance costs to business, and any attempt at protectionism.

The original amphibians evolved from fresh water fishes. It appears that they were 'preadapted' because the fish ancestors lived in pools and streams with little dissolved oxygen, requiring them to obtain oxygen from (initially) the richer film of water at the surface, and (later) from air itself. They adapted by developing highly vascular tissue at the roof of the mouth, where air would be held. This respiratory structure later evolved into lungs. They also preadapted by evolving fins that could hold them in shallow water so they could raise their heads to gulp air. Once those fins were strong enough, they could support the fish completely out of water - the road to becoming true amphibians. The classic intermediate form is Tiktaalik, which meets those criteria for a fish on the way to becoming an amphibian. http://en.wikipedia.org/wiki/Tiktaalik A step further along in evolution was Acanthostega. http://en.wikipedia.org/wiki/Acanthostega However, the evolutionary path was via fresh water - not salt - which explains why there are no salt water amphibians.

Actually there is a lot in favour of laissez faire economics. The British learned this after WWII. They were in a sad way at the end of the war, and were unable to go back to Hong Kong for nearly a year after the Japanese walked out. For almost a year, Hong Kong was left on its own, with no army, government, police force, education or health system. Just a whole lot of people who had to make do. When the first British governor got back into Hong Kong, the first thing he did was run a survey to find out the situation. To his utter surprise, he found that the Hong Kong people were doing very well, thank you. They were setting up small businesses. Some were growing food for sale. For police, they had local vigilante groups. For schools, they had entrepreneurs teaching kids for a fee. For health, they had nurses and doctors running their own clinics. The economy was not exactly thriving, since it was starting from a zero base, but it was growing at a staggering rate. The British governor was a smart guy and established a policy of minimal interferance. Really just law and order and defense. The result was that, at the time Hong Kong was handed back to the Chinese, it was perhaps the wealthiest place in Asia. Anything that has happened since does not reflect laissez faire.

To Bear I have not asserted my statements about using deuterium as fact. There are assumptions built in, and the conclusions depend on the assumptions. Like when I said that there was enough deuterium in the world's oceans to supply humankind with energy for a billion years at todays rate of use. Can you see the assumptions? Anyway, the point really is that there is more than enough deuterium for any reasonable projection into the future, if and when we learn to use it for energy. And any depletion over that reasonable projection time, will be so minimal that talking of ecological effects is kind of pointless. On the idea of the perfect city. There is no such thing. There may be an optimal design for a specific spot, and a specific time, and a specific people. But that will be different to every other place, time and people. I do not believe anything is ever 'perfect'. There is always room for improvement. Rather than tackling such a concept, it is much more practical to ask individual questions. ie. How can we improve : Paris New York London Sydney etc.

Reality check. Work on quantum gravity, wormholes, superstring etc is all no more than blowing bubbles, until and unless someone comes up with a testable hypothesis, which is then tested and not disproved. Even then, it just makes stronger bubbles. It takes many, many tests, and many many failures to disprove an idea, even obtained from maths or computer models, before it gains enough strength to be considered a fair to reasonable scientific model of reality. To get to the point of being accepted as a model so strong that it is close to considered true - well that takes decades and enormous amounts of work. Einstein's principles of general and special relativity are in this position, and are still being tested with the aim of disproving them. To get to the point where an idea is considered to be 'correct' takes something very, very special. The Atomic Principle, and the Principle of Biological Evolution now are so strongly backed by good evidence that we can pretty much call them 'proved'. But that takes masses of evidence. If you want to work on quantum gravity, be prepared for the enormous frustration that comes from never knowing whether what you are working on actually has any merit or not.

bascule That idea has been seriously studied by specialists. There was an article covering that in Scientific America, but a long time ago. A 2005 article in New Scientist is found at : http://www.newscientist.com/article/mg18625012.700 and I quote : "In fact, subduction zone insertion is perfectly sound in theory, but there are significant practical problems. The zones are inherently unstable and unpredictable, and the sediment on top of the subducting ocean crust plate tends to get scraped off rather than being carried into the mantle, to form what is known as an accretionary prism. This could lead to the waste being squeezed back to the seabed in the future. Drilling it deep into the basalt of the crust may solve this, but at the depths typically encountered in subduction zones, drilling is all but impossible"

Good to see. I am all in favour of electric cars. The problem of damaged batteries is no longer a problem if people do not own them. If all the batteries are basically rented, and exchanged willy nilly, then the rent money pays for battery replacement as required. A more important concern that I see is how to make sure enough electric power and power distribution is available. If the whole country goes electric, that would be a massive drain on both generation and distribution. Even if all charging is done at off peak times, that will only cover this change for up to a certain number of cars. After that, a lot more power is needed.

There is another possibility. If tachyons do not interact with normal matter and do not create a gravitational field, then they are indetectable - and we have not been able to detect them, so this idea is compatible with observation. For all we know, there may be an entire tachyon universe intersecting our own. With no interaction - why not?

Sisyphus The argument I put is that a reduction of deuterium in the world's oceans by 1% over one million years is seriously unlikely to have any significant or measurable ecological or biological effect. Are you really, seriously, honestly, suggesting I am wrong????

Sisyphus I am glad you agree with me. Can I ask you, what insult? I was not aware I had insulted anyone, and if so I apologise. Sometimes, when I suggest that a line of reasoning is not firm, it may be taken as an insult. But I am criticising the logic, not the person. On small amounts, and their biological effects. This is most clearly stated with regard to hazardous materials, in which the science of toxicology rules. The first principle of toxicology is stated as : "The dose makes the poison." (as worded by Paracelsus, the founder of modern toxicology in the 16th Century.) This principle says two things : 1. Everything is toxic at a high enough dose. 2. Nothing is toxic at a low enough dose. In terms of a chemical affecting biology or ecology, the principle is exactly the same. If the dose is low enough, there is no effect.

Sisyphus Is your irony detector malfunctioning?

Sisyphus It is not evidence. it is lack of evidence. There is exactly zero evidence that the tiny trace of deuterium in the oceans has any biological value. A few studies have shown that megadoses of D2O can have a small biological effect, which is, at best, a curiosity. However, 0.015% of water being deuterium having a biological effect of any kind, much less one that is essential to the ecology???? That really begs credulity. Remember that the only difference between normal hydrogen and deuterium is atomic mass. There is little or no chemical difference, and it is the chemistry that counts. In addition, even if humankind switched 100% to deuterium as its energy, and even if energy needs increased ten fold, the reduction in deuterium in the ocean over a full million years would be a mere 1%. To start raising ecological alarm over this is (not wanting to be insulting, so I am saying sorry in advance) just plain ridiculous.

To Bear In relation to nuclear power in developing nations. There has been a number of excellent suggestions from various government and business agents on this. One of the best is for large organisations within the USA or other western nations to supply the whole bang lot (for lots of $$$). That is, build the plant, supply the fissionable material, and take care of the waste. Since fissionable material for nuclear power can be one tenth the concentration required for nuclear weapons, it is really easy to ensure that the fuel is not used for weapons. This system would take care of the worst fears of nuclear power in third world nations. Reliable sources for the fact that minor leaks cause little harm? Certainly. My earlier post on radio-hormesis covers that. Another example is the detection of a hormesis effect among the Hiroshima survivors. http://www.ingentaconnect.com/content/tandf/bher/2001/00000007/00000004/art00016 While Hiroshima was a terrible event, killing so many people, and while high dose radioactivity among survivors led to lots of death by cancer, there was still a large subset of those affected by minor doses who have shown an actual increase in survival over the general Japanese population. This is but one of a vast literature on the beneficial effects of low dose radiation. Pangloss Re shooting waste into space. If we could separate out the radio-isotopes completely, it might be possible. There is 100 to 200 tonnes per year produced, and while costly, it might be possible. Sadly, the chances of so completely separating pure isotope is seriously improbable. Most of the isotopes are diluted with other material. Sometimes massively. In fact, when you take into account the weight of the diluents, you are dealing with tens of thousands of tonnes. If you were to shoot it into space, it would actually be energetically more sensible to fire it away from the sun. Space is so vast that it is very unlikely ever to be encountered again. To decelerate it enough to fall into the sun would be energetically close to impossible.

To Sisyphus A national government that is stacked with scientists and engineers is China. And it has an economy that is still growing at 7% per annum in the middle of the recession. Is there a message there?

Bear The percentage of deuterium in water is 0.015%. Since hydrogen is 11% of water, the deuterium is less than 0.2% of the hydrogen. If you think removal of this component is going to cause an ecological upset, your logic needs tweaking. In addition, the removal of deuterium would take untold millions of years. Hardly a trauma! Remember that my original statement was that the theoretical fusion energy of deuterium was enough for a billion years at humankind's curren energy usage. Even if humanity's energy demands increased very dramatically, the removal would be very, very slow. It is also interesting to note that the natural deuterium in comets is twice that of Earth's water. In the distant future, humanity is likely to extract much of its deuterium from extra-terrestrial sources. Distant future defined as anything over 1000 years. Nor is the amount of deuterium in natural waters sufficient even at maximum dose to have any biological effects at all. Neither of your two articles on biological effects of D2O actually stated how much heavy water they were using in their studies. I would guess, though, that it was massive doses compared to the amount of deuterium water there is in natural sources. In the article referenced at : http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=433888&pageindex=2 the D2O was supplied as 25% of total drinking water to get a biological response. Such quantities, compared to a 'natural' level of less than 0.2% make the 'natural' impact of deuterium probably zero. ie they had to increase deuterium 100 fold above natural levels to get a measurable response.

Bear Deuterium is a tiny part of the hydrogen in the water of the oceans. Removing it will have zero impact on ecology.

iNow It would be nice if you actually read my posts before you make claims like the above. I am not off topic. I am responding to some statements about fears of leaks of nuclear waste. I am also making constructive suggestions. ie. Australia and Africa. These are real practical possibilities, and a damn sight better than Yucca Mountain! It has been suggested in earlier posts that transport of nuclear waste is not possible because of the risk of losing that waste into the ocean. I have been trying to point out that this, in limited amounts, is not a disaster. Because the ocean is so big, and because small increases in background radiation are harmless, the risk of small losses is not sufficient to stop such transport.

iNow Like everything else on this planet it is a matter of balance. No we do not 'just leave it lying around'. However, I am opposing the blind paranoia some people have - hopefully not too many on this forum - of anything labelled 'radioactive' or 'nuclear'. In other words, we treat the nuclear waste with respect, and take measures to deal with it in the best possible way. However, we do not allow ourselves to be bound into inaction by irrational fears of minor increases in radioactivity. We find the best long term repository, but do not let ourselves refuse to transport it because there may be a minor leak, even as a remote possibility. Small increases in radioactivity do NOT cause disasters. There have been numerous minor nuclear leaks over the decades, and the harm from them is minimal. Only major leaks, or events lead to substantial harm. Chernobyl was the exception. A massive melt down and a massive increase in radioactivity. I remember an occasion perhaps 30 years ago when a Soviet satellite crashed to Earth, landing somewhere in northern Canada, and carrying a small nuclear reactor. There was panic for a time. However, the story just died down, and to my knowledge no significant harm was ever measured.

Just to throw another spanner in the speculative works... There is a hell of a lot of needless paranoia surrounding fears of radioactivity. While it is absolutely true that high doses of radiation are dreadful, there is no need to fear doses that are sufficiently low. Two points : 1. Look at Chernobyl. When the accident first happened, a lot of people died, and a bunch of children developed thyroid cancer. Not nice. However, it is interesting to see what has happened more recently. The government closed an area of 30 kms radius around Chernobyl. It has accidentally become a thriving wildlife reserve. There is a wonderful wilderness developing, with trees, deer, bears, wolves etc thriving within the area. Animals that spend time close to the old reactor will shown higher levels of mutation, but overall, the populations are thriving. http://news.nationalgeographic.com/news/2006/04/0426_060426_chernobyl.html 2. Radiation hormesis. Recent (last 20 years) research has shown that the harm from radiation is not linear. There appears to be a threshold below which, radiation becomes, not just harmless, but very likely actually beneficial. http://www.angelfire.com/mo/radioadaptive/inthorm.html Final conclusion : Yes, fear high doses of radioactivity, but do not get paranoid about low doses. Nuclear waste that is not locked away properly may cause background radiation in local areas to increase to a minor degree with no harm whatsoever.

To yd Sorry about ascribing those comments to you. But I wonder - what's with the guy who wrote them? Is he against sceptics in general or what? The comments were quite uncalled for unless he experienced something he has not spoken of?