SkepticLance

Bear The big assumption behind what I say is simply the assumption that humanity will crack nuclear fusion using deuterium. That is not certain. However, IF we do, then the rest is basic maths. The deuterium in water contain energy from fusion that is, in theory, 8 times that of oil. That is, one kilogram of water might release as much energy as burning 8 kg of oil. Since the oceans contain E18 tonnes, the rest is simple maths.

To yd As one of the sceptics you are criticising, let me say that I am not in the least offended. In spite of your vitriolic comments, there is very good reason to be sceptical of 'magic' tricks when they are claimed to be done by psychic abilities. The good reason is the long history of conjuring, and the enormous number of ways that exist to fool people, including sceptics. I have been challenged before by conjurer's tricks, and (mostly) I cannot figure out the exact way they are done. When they are revealed, I say, along with others, "Oh my God, it is so simple!" This experience, which most of us share in one form or another, is the basis for scepticism, and that is by far the most rational response.

To Bear. Re oceans and deserts. Nuclear waste decays slowly, to the point where, after 10,000 years, it may be treated as normal waste and disposed of in municipal land fills. Still slightly radioactive, but not enough to be a health risk. So the problem is simply to keep it safe that long. Not all deserts are suitable. As I said before, there are three main criteria for suitability. Geological stability, since we don't want the waste moved by earthquakes and volcanoes. Aridity, to stop containers corroding and contents carried by water. And lack of population to avoid people problems. I know of only two areas that are suitable. Southern Africa and Australia. Of the two, Australia is more suitable due to vast land area with no people. For ocean disposal, it is simply a matter for maths. The oceans contain E18 tonnes of seawater, making the dilution factor utterly incredible. The oceans already carry 50 million tonnes of radioactive Uranium 235 isotope, which creates the radioactive background. This level of radioactivity is something all life is already adapted to, and is therefore harmless. In fact, life can tolerate background level at least ten times higher. eg. In the mountain towns of Colorado, where the rocks of the mountains are slightly radioactive. This increase in radioactivity seems to be utterly harmless, and the cancer rates in the Colorado towns are lower than towns on the central prairies, where background radioactivity is way lower. If we measure only the radioactive component of nuclear waste - the isotopes themselves, and ignore all the inert materials that are mixed up with it, then the total world production of radioactive isotopes in nuclear waste is between 100 and 200 tonnes per year. Compare that to the 50 million tonnes of radioactive U235 already dissolved in the oceans, and consider whether man made waste would contribute to any meaningful level to background radioactivity in the oceans.

Invisible threads are commonplace in conjuring, and can move quite nicely under the edge of a bowl. I am probably barking up the wrong tree, but I noticed that the setting up of the spindle was done very quickly while the guy doing it was talking, possible as a distraction. The other thing that seems just too obvious is a tiny electric motor.

A thread around the vertical spindle?

Bear, fusion energy off the Earth will be fuelled by deuterium mined off the Earth. There is almost certainly water on Mars and the moon, in significant quantities, and water will be a big part of smaller clusters of matter such as the asteroids, or the moons and rings of Jupiter and Saturn. To extract deuterium on Earth and lift it through the gravity well for use in space makes little sense. It is energetically cheaper to move a tonne of deuterium from Saturn's rings to Earth orbit, rather than lift it from the surface. If humanity builds a space elevator, making transport into space cheap and easy, then we can move deuterium the other way if needed. Space to Earth. On Earth, if we get to use deuterium fusion energy, it really is not going to matter how much energy we will need, since the total is so massive. Once you get above a million year's supply, you might as well call it infinite. Who knows what the human species will be doing in a million years, or what its needs will be, or even if it still exists.

Bear Nuclear world wide is 12%. In countries like France, it is the dominant source. The USA uses coal, natural gas and oil as its main sources. How long do you think that can continue? The major release into the atmosphere of radioactives comes from burning coal. Nuclear power by comparison releases next to nothing. And the radioactives from coal are the least harm from this source of energy. Coal is the real nasty in the world today - not nuclear. Wind uses enormous amount of land area and is immensely ugly. James Lovelock says that each Gigawatt requires 2500 sq. km of land. Right or wrong, it is clear that wind energy is not the answer, though it will have a place. Solar is still too expensive. Hot rock is the best new technology but is still a few years away. Hydroelectricity is oversubscribed already. Wave energy is probably a couple of decades away. Of all the proven technologies, the one with the greatest potential is nuclear. China is building a number of nuclear power stations, though it still relies too heavily on coal. It is developing renewables, sure - but they are still a minor part of total generation. It is rapidly using up its available hydroelectric resource. The biggest problem with disposing of nuclear waste is not technical. There are several methods available right now. The biggest problem is political - getting people to agree on what to do. I have pointed out that the Australian desert is a safe repository. Also that solution in the ocean would work. Others pointed out the possibility of recycling. There is also an area in southern Africa that meets the three criteria for a long term repository - geologically stable, totally arid, and with next to no people living there. Yucca Mountain does not meet those three criteria, and is definitely not ideal. Transporting nuclear waste to a better long term store can be done with reasonable safety using modern methods of encasing the waste. No, it is not 100% perfect, but what is? And we already know that a shipload or two of waste in the oceans will do little harm. Many shiploads are already mouldering on the seabed, and doing no harm that has been measured. Large amounts of waste in steel drums, long since corroded to nothing, were dumped in the 1950's on the sea bed and there are several nuclear submarines also on the seabed, with their reactors slowly leaking into the sea. No significant harm has been detected from these. So let's not get paranoid about the possibility of a wee bit more, in carrying the waste to an essential long term repository.

To Bear So energy use expands ten fold and we have 'only' 100 million years supply. I do not think I am ging to lose much sleep over that.

There is no such thing as a perfect city. Even those who praise Singapore have obviously not visited average apartments, which are small and cramped. I would hate to have to live in one. Energy supplies have many options. If fusion of deuterium is ever made practical, then there is enough deuterium in the oceans of our world to provide humankind with electricity at today's rates for a billion years - till long after the warming sun makes our planet uninhabitable. In the short term (20 years), nuclear power and hot rock geothermal are more practical. Medium term (20 to 50 years) - oceanic wave energy can provide masses of power. Ditto solar. Long term? Maybe fusion??

Janus. That is fine, but purely theoretical. Attempts have been made to detect tachyons, without success. Until we prove empirically we can detect tachyons, we cannot detect tachyons.

bascule You may note that I was talking of the 1950's, for long term disposal, before dry cask storage. Even dry cask really cannot be used immediately, due to the high heat emission of fresh waste. Actually, the US has dumped relatively little waste at sea compared to the USSR. http://www.nti.org/db/nisprofs/russia/naval/waste/wasteovr.htm There has been a lot of activity by environmentalists in the past opposing the disposal of nuclear waste at sea, and it is now something of a dirty concept. The silly thing is that very little evidence exists of any significant harm from such disposal, though there is a lot of literature about potential harm. I have also rather liked the idea of storing radioactive waste for a few years to get rid of short half life isotopes, and then dissolving the residue in acid, diluting it massively, and dispersing it out over the oceans. The actual quantity of radioactive Uranium 235 dissolved naturally in the oceans is about 50 million tonnes, and the extra tonnage of radioactive isotopes will be small by comparison. The great thing about this method is that it is final. However, it is not politically correct!

To Mokele The article I read on the subject was not specific in detailing how it was investigated. Just that the US Navy was assiduous in checking. You can take that with a pinch of salt if you wish. However, it makes sense. The oceans are vast beyond our conception, with E18 tonnes of seawater. Any dissolved isotopes will be diluted to insignificance in no time, while any that remain undissolved will sit locally within sediments, and probably have little effect except on organisms that sit there long term. And on exposing people to the radioactivity from waste, even without much shielding, the inverse square law means you do not have to be far from the waste before the level of extra radioactivity drops to the point of harmlessness. Combine a small amount of shielding with a reasonable distance within a ship of the living and working quarters from the waste storage, and the problem essentially disappears.

Transporting waste by ship is no different than transporting it by rail. It is vulnerable both ways. And no, the operators would not be seriously affected by radiation. A modest distance from well shielded waste will be sufficient. I might add that the preliminary to any method of dealing with nuclear waste is to store it in a secure place - probably under water - for a few years, without moving it anywhere. The short half life isotopes decay in that time, and reduce the immediate radioactivity by a massive amount. I might add that a sunk ship would not be a global catastrophe. In the 1950's the standard method of dealing with nuclear waste was to put it into steel drums and dump it in the deep ocean. Those drums have long since rusted open and released all that waste, and there is no empirical evidence whatever of environmental harm. And that was many ship loads! Another ship load is not going to change the situation to any measurable effect. Plus we have much better methods today of storing and transporting nuclear waste without rapid release into the environment.

Ozone is an excellent algicide, and is made by discharging electricity through air. You can control algae in a private pool in this way, and there are commercial products to make the ozone. Just on the side, if you use copper sulfate, remember that it is incompatible with aluminium. If you have aluminium ladders or rails, you will see the copper corrode them.

In terms of pure relaxation, the answer is - it depends.... In fact, everyone is different. For some people, music is the answer. For others, quite the reverse. Certain types of music leave me feeling very stressed. However, I am not musical. I have found for myself that the best stress relieving exercise involves immersion in the sea. For some reason, I exit feeling like all my troubles have disappeared. But that is me. So the answer is; whatever blows your hair back, brother.

The solution requires international cooperation. Australia has regions of desert, utterly arid, which are in a geologically stable location which will unlikely have anything happen geologically for the next 10 million years, and which are 1000 kms from the nearest large town. Pay the Aussi's megabucks to dig a bloody great hole in the ideal location, and there is room for waste for the next 10,000 years, and an income stream that would make Australia the richest nation of Earth.

buttacup There are two kinds of eczema - contact and atopic. Contact eczema, as you know, comes from touching something you are sensitive to. Usually, this shows by being very localised, since it flares up only where the contact has been made. Is your eczema localised in this way? If so, does the location on your body, and the shape of the rash give a clue?

Basically, as Paralith said, it varies. It also varies according to lecturer/tutor. However, if you have a true fascination for the subject, it will be fascinating. You will love it. I would suggest you try to include some subjects, though, that are more marketable in the job market. Zoology is incredibly interesting, but there are not too many jobs for zoologists, even if they end up with a Ph.D. If you have side subjects such as chemistry, maths, statistics etc., it may help eventually land a good job. I did zoology and botany. But I also did chemistry and microbiology. Guess which subjects gained me a career?

International take a scientist to the pub and buy him/her free drinks day.

There was an article on wormholes in Scientific American several years back. They stated that 'natural' wormholes would be so small that not even a photon could pass through - hence conserving the laws prohibiting travel faster than light. They also said that, in theory, to build a wormhole large enough to pass a man, you would need vast amounts of 'negative energy'. This negative energy is purely theoretical. It has never been proved to exist, and humanity has no way to make or collect it. Sad.....

There is often a bit of misunderstanding on this. It is not that anything cannot go faster than light - it is that nothing can accelerate to light speed. It is a bar to acceleration - not velocity. To accelerate something to light speed would take infinite energy - hence impossible. Tachyons are hypothetical particles that were created at a speed greater than light. They go faster than light because they have never had to accelerate through the light barrier, which would take infinite energy. However, as pointed out before, tachyons so far, are purely imaginary particles. They have never been detected. Nor do we know of any way to detect them. They are theoretically possible, but there is no theoretical impetus to suggest they have to exist.

Here in New Zealand, we also have parliamentary 'question time'. The only downside is that the opposition tend to use it as an opportunity to try to embarrass the government, rather than for constructive purpose. Overall, though, it is probably worth doing. It certainly publicises any flaws in government policy!

Sayonara said : "Lance, look at what you are saying here. "The physical measurements correlate with intelligence". How was that level of intelligence established? Could it have been with... IQ tests?" The truth is that the article did not specify. There are many ways of measuring intelligence, and they must all be correlated against each other to gain any meaning. IQ tests have a certain limited value. They do not seem to work when comparing people from different cultures, but have meaning when comparing people within one culture, and within the same socio-economic level. I was also interested to note in another article I read some years ago, that IQ within one culture correlates closely with neuron impulse transmission speed. The article I quote in this thread also refers to this parameter. It may be that we need to develop better methods of measuring neuron impulse velocity and use that as a more objective measure. It would even have value across cultures!

One of the things that is, perhaps, a bit different about the study I quoted is that it is based on physical measurements, rather than dubious IQ tests. That is, the mass of brain cell, and wate rmovement within the brain. Both correlate closely with intelligence, and both measures are much closer in identical twins than in fraternal. This method escapes the problems of interminably debating how accurate IQ tests are. While you could argue that the above measures are only indicative of intelligence, you cannot argue that what they measure is meaningless, since they are direct physical measurements. Good science!

Sayonara I know you are being light hearted, and that is good. If the perfect creator created us with a separate breathing cloaca (fused nostrils?), the designer would also create us to appreciate the aesthetics of a handsome hole! Imagine the street corner scene. "Whoooah, look at the cloaca on that one!!"