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1402
Physics, Astronomy & Cosmology / Re: Could you become a God by traveling at the speed of light?
« on: 26/10/2015 21:32:47 »
Could you become a God by traveling at the speed of light?
No. Or possibly Yes. But since you can't travel at the speed of light, don't waste too much time on the subject.
No. Or possibly Yes. But since you can't travel at the speed of light, don't waste too much time on the subject.
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1403
Geology, Palaeontology & Archaeology / Re: When during human evolution did the first scientist appear?
« on: 25/10/2015 20:52:58 »
No. Evolution is about what the cell did next, not how it came into existence in the first place.
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1404
Geology, Palaeontology & Archaeology / Re: When during human evolution did the first scientist appear?
« on: 22/10/2015 23:59:10 »
In 1983 I watched a gorilla at Chessington Zoo discover the principle of universal gravitation. He had two apples, one considerably larger than the other, one in each hand. He dropped them and noticed that they hit the ground at the same time. He repeated the test, twice, then changed hands and did it again. Perfect null experimental technique: observe, repeat, change one parameter.
On the presumption that gorillas don't read books or have much of an oral tradition of scientific knowledge, this chap discovered, by the application of best scientific practice and in the space of five minutes, what took humans several million years and and a fair bit of bloodshed. Indeed there is no historical evidence that Galileo actually did his "leaning tower" experiment, and if you read some of the bizarre submissions to this forum, it's quite clear that very few humans appreciate even the simplest principles of scientific investigation. Of course the gorilla didn't have to shake off centuries of superstition and the threat of excommunication, which gave him a huge advantage over Bruno et al.
Having seen birds, rats and chimpanzees deduce causal relationships from observation, and having marvelled at the gullibility of humans (including verbatim acceptance of garbage like Genesis) for many years, I fear that scientific thought in homo sapiens is something of a rarity compared with other species. Worse: when it appears, the herd generally tries to stamp it out, always preferring consensus and superstition to the demonstrable truth - unlike blue tits.
On the presumption that gorillas don't read books or have much of an oral tradition of scientific knowledge, this chap discovered, by the application of best scientific practice and in the space of five minutes, what took humans several million years and and a fair bit of bloodshed. Indeed there is no historical evidence that Galileo actually did his "leaning tower" experiment, and if you read some of the bizarre submissions to this forum, it's quite clear that very few humans appreciate even the simplest principles of scientific investigation. Of course the gorilla didn't have to shake off centuries of superstition and the threat of excommunication, which gave him a huge advantage over Bruno et al.
Having seen birds, rats and chimpanzees deduce causal relationships from observation, and having marvelled at the gullibility of humans (including verbatim acceptance of garbage like Genesis) for many years, I fear that scientific thought in homo sapiens is something of a rarity compared with other species. Worse: when it appears, the herd generally tries to stamp it out, always preferring consensus and superstition to the demonstrable truth - unlike blue tits.
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1405
Chemistry / Re: Could a solar powered cooling system be used to collect water from the air?
« on: 16/10/2015 17:41:30 »Assume a coefficient of performance of about 2. Your 150W refrigerator can therefore shift about 300W of heat. Condensing 1 gram of water requires about 2300 joules of heat to be extracted, so you can condense 300/2300 = 0.13 gram per second. If the water content of air is about 5% you need to pass 20 x 0.13 = 2.6 gram of air per second over your condenser - about 2 liters/second. You can probably achieve this with a 2W fan, which won't impose a significant load on your power supply.
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1406
Physiology & Medicine / Re: Urinating on the moon.
« on: 15/10/2015 22:58:10 »
A pee tube is built into any pressure suit intended for long-term wear. Short-term you use a nappy (diaper).
Glider pilots suffer from cold: a flight of more than 3 hours becomes a test of bladder control and moral fibre as much as airmanship. So some gliders have a venturi waste tube attached to a rubber cup (known in less PC days as the "Polish microphone" - well, it was invented in Poland) but a fighter test pilot, accustomed to having proper personal plumbing in his office suit, attached himself to a glider venturi with a transparent polythene bag. The other thing glider pilots suffer is sunburn. The experiment was well publicised in the 1970s and I don't think has been repeated.
Glider pilots suffer from cold: a flight of more than 3 hours becomes a test of bladder control and moral fibre as much as airmanship. So some gliders have a venturi waste tube attached to a rubber cup (known in less PC days as the "Polish microphone" - well, it was invented in Poland) but a fighter test pilot, accustomed to having proper personal plumbing in his office suit, attached himself to a glider venturi with a transparent polythene bag. The other thing glider pilots suffer is sunburn. The experiment was well publicised in the 1970s and I don't think has been repeated.
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1407
New Theories / Re: Newton's 3rd Law + Logic = Genesis?
« on: 15/10/2015 00:51:47 »
The universe contains stuff, which we observe behaves in certain ways, called physical laws.
Now consider that there may have been a time when the stuff did not exist. There being no stuff to behave, there were no observables that could be set down as physical laws. The laws are a summary of the existence and behaviour of stuff: they are descriptive, not prescriptive, which is why it is no big deal if classical mechanics doesn't describe what goes on inside an atom or a black hole, or at very high relative speeds.
So if the laws of physics applied before stuff, to what did they apply? You will have to postulate protostuff which, having the same physical properties as stuff, must therefore be stuff.
Thus the postulate that the laws of physics applied before the creation of the universe is inconsistent with the notion of a point of creation.
Now consider that there may have been a time when the stuff did not exist. There being no stuff to behave, there were no observables that could be set down as physical laws. The laws are a summary of the existence and behaviour of stuff: they are descriptive, not prescriptive, which is why it is no big deal if classical mechanics doesn't describe what goes on inside an atom or a black hole, or at very high relative speeds.
So if the laws of physics applied before stuff, to what did they apply? You will have to postulate protostuff which, having the same physical properties as stuff, must therefore be stuff.
Thus the postulate that the laws of physics applied before the creation of the universe is inconsistent with the notion of a point of creation.
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1408
General Science / Re: How would you operationalize Authority?
« on: 12/10/2015 16:09:37 »Quote
"Command authority" is the authority leaders have over soldiers by virtue of rank or assignmentwhich, though easy to assess, I suspect isn't really what you mean. However we do use the term as a variable attribute when assessing civilians for roles of leadership or responsibility. You could usefully talk to personnel officers in large companies, examiners for mariners or aviators (especially traffic controllers in those media) or police instructors.
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1409
Marine Science / Is space or sea exploration the better use of our resources?
« on: 20/08/2015 22:35:14 »
Considering how much tax revenue is wasted on wars (on drugs, terror, cancer, or just rearranging the rubble in Afghanistan) banks, and friends of politicians, any such discussion simply diverts critical attention from high level corruption. Whilst the peasants argue over the distribution of crumbs, those we elect to take our money feast on the real meat.
The following users thanked this post: Zer0
1410
Physiology & Medicine / Re: Why are more people right handed than left handed?
« on: 13/07/2015 16:27:59 »
Handedness is a peculiar phenomenon. Most distributions in nature are either fairly even (male/female ratio in mammals) or very rare (reverse heart anatomy) but lefthandedness seems to occur somewhere in the 10 - 25% range.
My hypothesis is that about half of the human population is genetically incapable of being lefthanded, due to the brain having to learn all sorts of difficult things like standing on two feet, and talking. Quadrupeds and animals with a smaller vocabulary don't seem to be particularly handed in comparison. So in about half the population all the complex motor skills are, say, lodged in the left half of the brain whereas the other half of the population they are distributed more evenly.
Now society requires us to abide by certain hand conventions, and half of us can't use lefthanded tools, so the general convention is to use the right hand for fine motor control. This gives 50% of the population a choice to go with the flow or be different, and by Bayesian statistics about half of the "born ambis" choose to live as dextrals, possibly enjoying some advantage in twohanded skills like music and sport, whilst the remainder (which may include a very few "genetic sinistrals") use the left hand.
This may explain a few observed phenomena: a signficant number of lefthanded "creatives" including many composers (though few instrumentalists), mathematicians, and high-flying executives (lefthanded CEOs apparently earn 10% more than righthanders in FTSE companies) and politicians.
There was a reported association of lefthandedness with speech and hearing defects but AFAIK this phenomenon is statistically weak. I think there may indeed have been a case some years ago when schools insisited on righthanded writing, that the few who simply couldn't do it were "genetic sinistrals" and may indeed have had genetic problems of coordination, but with a more tolerant education system they have been diluted by the "lefties of choice".
My hypothesis is that about half of the human population is genetically incapable of being lefthanded, due to the brain having to learn all sorts of difficult things like standing on two feet, and talking. Quadrupeds and animals with a smaller vocabulary don't seem to be particularly handed in comparison. So in about half the population all the complex motor skills are, say, lodged in the left half of the brain whereas the other half of the population they are distributed more evenly.
Now society requires us to abide by certain hand conventions, and half of us can't use lefthanded tools, so the general convention is to use the right hand for fine motor control. This gives 50% of the population a choice to go with the flow or be different, and by Bayesian statistics about half of the "born ambis" choose to live as dextrals, possibly enjoying some advantage in twohanded skills like music and sport, whilst the remainder (which may include a very few "genetic sinistrals") use the left hand.
This may explain a few observed phenomena: a signficant number of lefthanded "creatives" including many composers (though few instrumentalists), mathematicians, and high-flying executives (lefthanded CEOs apparently earn 10% more than righthanders in FTSE companies) and politicians.
There was a reported association of lefthandedness with speech and hearing defects but AFAIK this phenomenon is statistically weak. I think there may indeed have been a case some years ago when schools insisited on righthanded writing, that the few who simply couldn't do it were "genetic sinistrals" and may indeed have had genetic problems of coordination, but with a more tolerant education system they have been diluted by the "lefties of choice".
The following users thanked this post: Zer0
1411
Guest Book / Re: Nurse and Mother of a budding scientist
« on: 17/11/2014 23:34:41 »
Apologies. I thought the webcam was switched off. But welcome anyway, and tell the lad that Fibonacci was publishing around 700 years ago, so his numbers will keep until after breakfast, surely.
The following users thanked this post: Zer0
1412
Technology / Re: Can you make a power shower with induction heating?
« on: 16/09/2014 09:42:58 »
Yes, but if it only takes 5 watts of electrical power it will only deliver 5 watts of heat (minus all the inefficiencies of the inverter). If you want to wash with flowing water at 2 liters/minute you need about 3,000 watts to raise the incoming water (at say 20 deg C) to 40 degrees. The best way to achieve that is with an immersed resistive heater, which is about 99% efficient at coverting electrical energy into useful heat (you lose about 1% heating the incoming wires) - i.e. an ordinary power shower.
Best of all, immerse yourself in a well insulated bath (say a styrofoam coffin) with a tiny amount of water, and wait until the 200 watts of your body heat has raised the water temperature to about 30 degrees, then apply soap. No electrical power, minimal waste water - the ultimate ecobath!
Best of all, immerse yourself in a well insulated bath (say a styrofoam coffin) with a tiny amount of water, and wait until the 200 watts of your body heat has raised the water temperature to about 30 degrees, then apply soap. No electrical power, minimal waste water - the ultimate ecobath!
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1413
Technology / Re: Can 40 x 2500mAh AA batteries replace one 100Ah lead acid battery?
« on: 24/04/2014 08:47:16 »
Beware of assembling large stacks of cells that aren't designed for such assembly! You can get away with 10 x AA NiMH cells in series because in the event of one failing open-circuit the voltage across it will only be 10.8V. But if you put 40 cells in parallel and one fails short-circuit, the prospective fault current through the dud cell is several hundred amps and more than likely to burn a hole in your boat.
Face it, lead-acid batteries are crude, oldfashioned, heavy, but extremely robust, tolerant and reliable for high current demand. There's a good reason why they are the only approved technology for most small planes, and judging from the problems Boeing are having with Dreamliner batteries, I'd rather have a PbAc in a boat than anything else right now.
Face it, lead-acid batteries are crude, oldfashioned, heavy, but extremely robust, tolerant and reliable for high current demand. There's a good reason why they are the only approved technology for most small planes, and judging from the problems Boeing are having with Dreamliner batteries, I'd rather have a PbAc in a boat than anything else right now.
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General Science / Re: Would legalization of Marijuana increase general health?
« on: 01/02/2014 08:01:38 »Hence my suggestion that "DUA" should be replaced by "attempted manslaughter" regardless of the state or cause of intoxication.
Unlike alcohol, the active ingredients of Marijuana are not a single volatile chemical, so testing for dangerous intoxication will be more expensive, time-consuming and intrusive, whether by the roadside or in the workplace.
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I am not sure that "other intoxicants" are a good basis for deciding what is good for us.We know exactly what is good for us: fish and chips, water, and nothing else. Any stimulant, depressant, or other psychoactive substance is potentially harmful. But so is skydiving and shark fishing. The legislative question surely is whether we harm or inconvenience others by our actions.
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The medical impacts of tobacco, who knew what, was it ethical for them to suppress & confound the scientific evidence, and did they have a responsibility to tell the public. There are now slow and laborious efforts underway to restrict it to places where it won't cause so much damage public health (eg no smoking in the workplace, or around children).Now we are getting sensible about it.
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We have seen a recent discussion in the UK about legislative action to control excess alcohol consumption, and also in Australia.But only among the poor. Minimum unit pricing won't stop me (or any member of parliament) getting dangerously drunk on good wine and fine malt whisky, for which I am already paying well over the minimum, but it will encourage smuggling, homebrewing and theft of cheap stuff. Total prohibition took the Mafia from being minor racketeers to being the fastest-growing business in the USA. They still control large areas of the food and drink industry, and for as long as drugs remain illegal, criminals will continue to run the country.
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In other words, we are now trying hard to undo the damage done by common practice in a previous era where scientific evidence was not a criterion for acceptability.Who we? The dangers of smoking have been well publicised since the 1950's and are repeated on every packet of tobacco, but smokers surely have as much right to harm themselves as skiers and racing drivers, and some continue to exercise that right.
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I welcome conducting scientific studies that may show that cannabis is "generally quite harmless", but the difficult part will be showing that it has an overall benefit to society (ie the benefits outweigh the costs), and so it should be legalised.What is the societal benefit of rock climbing or ocean racing? Both impose an occasional burden on rescue services and frequently kill or injure the participants, but nobody has thought to ban them.
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I think the hardest part of the costs to assess will be whether legalising cannabis will lead to a reduction in harms from alcohol, tobacco or other drugs.One thing at a time, please.
The principal effect of decriminalising any drug will be to save police time and reduce the flow of money into criminal pockets. The secondary effects will be to increase the purity and consistency (and thus reduce the unintended toxicity and burden on health services) of stuff sold under licence, to increase Treasury revenues from licensing, and to reduce the attractiveness of a prohibited activity (instead of being what teenage rebels do behind the bike sheds, it will be what sick old people do to relieve the pain of cancer - what could be more offputting than that?)
Whether it has any effect on the consumption of other legal substances is of no consequence to anyone except HM Treasury and the industries that supply those drugs. Let the market decide.
This week's good news is the decision of the Welsh Assembly to make the public health laboratory service available to all drug users: you can send them a sample of your latest purchase and they will tell you what it contains. Then it's up to you. Presumably if it turns out to be 50% rat poison you will kick the bejasus out of your supplier and thus solve the problem for others. What a sensible, adult way to run a country - or at least a sensible beginning.
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1415
General Science / Re: Would legalization of Marijuana increase general health?
« on: 30/01/2014 11:47:25 »
Government has no legitimate interest in what adults do to themselves.
All drugs should be legalised, but the penalty for supplying any intoxicant to a minor should be suitably draconian: the supplier must kill himself with an overdose of whatever he supplied.
The penalty for injuring a third party whilst intoxicated should be aligned with that for intentional harm. No excuses: you can smoke, swallow, snort or inject anything you fancy (and if you buy it tax-paid from a licensed pharmacist you can be sure that it is good stuff) but you and you alone are responsible for your actions at all times.
What, you may say, about a parent giving a child wine with a meal? IMHO that is the only point worth debating.
All drugs should be legalised, but the penalty for supplying any intoxicant to a minor should be suitably draconian: the supplier must kill himself with an overdose of whatever he supplied.
The penalty for injuring a third party whilst intoxicated should be aligned with that for intentional harm. No excuses: you can smoke, swallow, snort or inject anything you fancy (and if you buy it tax-paid from a licensed pharmacist you can be sure that it is good stuff) but you and you alone are responsible for your actions at all times.
What, you may say, about a parent giving a child wine with a meal? IMHO that is the only point worth debating.
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1416
Chemistry / Re: What is the difference between an "atomic" and a "nuclear" bomb?
« on: 16/01/2014 01:17:18 »Quote
Civil liberties have taken some punishmentwhich appears to have been part of the objective - to impose a police state on a democracy. The other objective, to start a war between civilisation and Islam, seems also to have been achieved. A brilliant plan, superbly executed, and the idiot Bush fell right into the trap. Which wouldn't matter if he hadn't dragged the rest of us in with him.
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1417
Chemistry / Re: What is the difference between an "atomic" and a "nuclear" bomb?
« on: 15/01/2014 22:27:45 »
No need to make when you can buy or steal. And if you just want to create panic and bring down a government, a conventional explosive with some easily obtainable radioactive waste will do the job nicely. Indeed as 9/11 showed, you can destroy democracy with a knife.
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1418
Just Chat! / Re: "woefully undertreated" chronic pain
« on: 06/12/2013 09:36:57 »
Whose life is it?
IMHO every adult should be allowed to shoot, sniff or swallow any damn thing he likes.
If the pain gets too bad, the law won't object to your jumping off a bridge or blowing your brains out, so why should anyone object to selfmedication that prolongs your useful life?
IMHO every adult should be allowed to shoot, sniff or swallow any damn thing he likes.
If the pain gets too bad, the law won't object to your jumping off a bridge or blowing your brains out, so why should anyone object to selfmedication that prolongs your useful life?
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1419
Technology / Re: How can renewable energy farms provide 24-hour power?
« on: 28/08/2013 10:13:03 »
Excellent technology, with serious economic consequences.
The problem with unreliable energy sources is that if they account for more than about 10% of the maximum grid capacity, they make the entire system uneconomic. If the wind blew at rated speed for 90% of the time, you would need 10% of your reliable sources to be switched off for 90% of the time in order to cover the gaps. This might be tolerable, but idle machines need space and maintenance, so they represent a financial loss (and the wind generally only blows at 10% of rated speed). Above 10% of unreliables, it is difficult to persuade anyone to invest in conventional plant: big nukes and clean coal take a long time to fire up, small ones are expensive; gas plant costs less to install but is at the mercy of suppliers on the other side of the world; and whilst oil can be stockpiled, it is horrendously expensive to run. The sensible investment is in nuclear and big coal plant, but the prospect of at least 20% overcapacity or underutilisation will not attract shareholders.
So rather than impose levies on conventional power in order to subsidise unreliables, government should require windfarmers and the like to subsidise conventional standby plant, or require them to install at least 5 days' storage capacity at rated power, and insist that the store is full before allowing them to supply the grid directly.
The problem with unreliable energy sources is that if they account for more than about 10% of the maximum grid capacity, they make the entire system uneconomic. If the wind blew at rated speed for 90% of the time, you would need 10% of your reliable sources to be switched off for 90% of the time in order to cover the gaps. This might be tolerable, but idle machines need space and maintenance, so they represent a financial loss (and the wind generally only blows at 10% of rated speed). Above 10% of unreliables, it is difficult to persuade anyone to invest in conventional plant: big nukes and clean coal take a long time to fire up, small ones are expensive; gas plant costs less to install but is at the mercy of suppliers on the other side of the world; and whilst oil can be stockpiled, it is horrendously expensive to run. The sensible investment is in nuclear and big coal plant, but the prospect of at least 20% overcapacity or underutilisation will not attract shareholders.
So rather than impose levies on conventional power in order to subsidise unreliables, government should require windfarmers and the like to subsidise conventional standby plant, or require them to install at least 5 days' storage capacity at rated power, and insist that the store is full before allowing them to supply the grid directly.
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