legov Posted March 31, 2011 Share Posted March 31, 2011 Some shit about Einstein, relativity et al, never really got it. Absolute zero on the other hand is so simple, it's just the complete absence of heat. Link to comment Share on other sites More sharing options...
rjw63 Posted March 31, 2011 Share Posted March 31, 2011 Out of an 8 hour working day, the Understudy spends 3.5 hours on VT and 4 hours on Facebook. Only a matter of time til his employers catch on Link to comment Share on other sites More sharing options...
Gingerlad Posted March 31, 2011 Share Posted March 31, 2011 The other half hour is his lunch break. When he knocks one off. Link to comment Share on other sites More sharing options...
LondonLax Posted March 31, 2011 Share Posted March 31, 2011 what's so scientifically ambiguous about that? The notion that we can't go lower than that. I don't accept the limitation. I've always not understood the notion that we can't go faster than the speed of light. Obviously we'll never be advanced enough to actually travel that fast. But as I understand it, even if we had somethign powerful enough, we would be physically unable to go faster than the speed of light. It's only a speed, why can't we go more than that? I have looked about and found an article explaining it in simiple terms. It would appear to be a matter of whether you believe Einstein's theory is true or not. Can anything travel faster than the speed of light? March 23, 2006 Can anything travel faster than the speed of light? "No," is what Albert Einstein would likely say if he was alive today -- and he would be the man to ask, because scientists have been taking his word for it ever since the early 20th century. According to Einstein's theory of special relativity, published in 1905, nothing can exceed the speed of light. That speed, explained Einstein, is a fundamental constant of nature: It appears the same to all observers anywhere in space. The same theory says that objects gain mass as they speed up, and that speeding up requires energy. The more mass, the more energy is required. By the time an object reached the speed of light, Einstein calculated, its mass would be infinite, and so would the amount of energy required to increase its speed. To go beyond the infinite is impossible. One hundred years of testing have only reinforced what Einstein wrote, said Donald Schneider, professor of astronomy and astrophysics at Penn State. "There is no experiment that has contradicted special relativity. We have accelerated sub-atomic particles to well over 99 per cent of the speed of light, but not equal to or exceeding the speed of light. "Theoretically, strange things happen when you exceed the speed of light," Schneider added. Time travel, for one thing, and a breakdown in cause and effect. Schneider uses an example of hitting a target with a gun that shoots bullets faster than the speed of light. "Some observers would see the bullet hit the target before they saw the shooter fire the gun," he said. "Since one of the guiding principles of relativity is that all physical laws are the same to all observers, this violation of causality would be a big problem." Another oddity: tachyons. In 1967, Gerald Feinberg, a physicist at Columbia University, proposed the existence of these faster-than-light particles. In their mirror world above the light-speed barrier, tachyons would require infinite energy to slow down to the speed of light. Other concepts that have popped up include "wormholes" -- shortcuts through space-time that would permit point-to-point travel faster than light -- and "warp drives," a kind of bubble created in space in which relativity wouldn't apply. Although they have become staples of science fiction, tachyons, worm holes and warp drives remain speculation, and many physicists dismiss their significance. There is, however, at least one real-world example of superluminal (i.e., faster-than-light) travel. It occurs when light passes through water. In this dense medium, Schneider explained, light is slowed to three-fourths of its speed in a vacuum. In a nuclear reactor, charged particles flying off the radioactive rods through the water they are submerged in exceed this reduced speed. Because these particles contain an electric charge, they emit energy, called Cherenkov radiation. Any particles they bump into become radioactive, giving the water a characteristic blue glow. "It's not at all exotic," Schneider said. "Every time you look at the water in a nuclear reactor, the bluish glow you see is radiation produced by charged particles moving faster than the speed of light in the water." Still, slowing light down in order to beat it is cheating, Schneider conceded. And although he's not closing his mind to the possibility that relativity will one day be amended, for now, he said, Einstein's theory is the final word. here Link to comment Share on other sites More sharing options...
legov Posted March 31, 2011 Share Posted March 31, 2011 "Theoretically, strange things happen when you exceed the speed of light," Schneider added. Time travel, for one thing, and a breakdown in cause and effect. Schneider uses an example of hitting a target with a gun that shoots bullets faster than the speed of light. "Some observers would see the bullet hit the target before they saw the shooter fire the gun," he said. "Since one of the guiding principles of relativity is that all physical laws are the same to all observers, this violation of causality would be a big problem." That's the main issue i have with the theory. This only means that time appears to stop / go awry, doesn't mean that that happens in actual fact. It's like an optical illusion. Link to comment Share on other sites More sharing options...
Chindie Posted March 31, 2011 VT Supporter Share Posted March 31, 2011 The crocodiles don't age thing is not as simple as saying 'crocodiles are immortal'. Nothing dies of age. Age in many things makes death more likely, true, but a lot of large reptile species have 'negligible aging' giving them no real negative to the length of their life. Scientifically 'age' (as in the march to becoming elderly) is measured on the functionality of the body becoming curtailed over time. In these creatures that have negligible aging, the point at which they have their body start to fail or lose functionality never comes, and so scientifically, they don't really age. Time is still passing by for them obviously and their cells are still aging (meaning they're not immortal), but this does not cause them to lose functionality. All that means is that they can live, in ideal conditions, for exceptionally long periods of time. They'd still die eventually, simply because chances are, longer you live, the more chance of something 'going wrong', i.e. being killed, starving, catching a disease, developing a genetic disease, etc. It's basically the same thing a tortoise does, and we're not amazed that tortoises live for a couple of centuries in some cases. Theoretically, because nothing dies of age, anything could become immortal. The only reason humans (assuming we live perfect lives and don't succumb to things like heart disease or strokes, or contracted disease) die is that our biology starts to show faults as our cells divide and we inevitably get cancer that will sooner or later kill us, or our genes cause other diseases that eventually cause our death. Solve the problems of our genetic makeup and we may never die. That would solve aging as well most likely, although ironically we need our cells to age to stop cancer occuring (as cells age they become more likely to 'go cancerous', they have a biological clock that encourages them to self destruct at a certain age - cancerous cells are often cells that simply were prevented/'forgot' to die), so we would need to develop a genetic solution to not age as well as stop cancer. The unfortunate thing with that occuring however would be we'd actually be doing more damage than good - it's good for the species for the elderly to die sadly and it's good for the species for it to have the elderly to die. If we all ran around in our prime for ever we'd rapidly destroy ourselves. There are a number of animals that are bonfide immortal - only dying through trauma or disease. There is a type of jellyfish that, after fulfilling it's role in sexual reproduction, effectively puts it's life in reverse, growing young again, then bouncing back to maturity again IIRC. And then there's water bears, a creature that not only doesn't age whatsoever, is also **** hard to kill - if they find themselves in an environment that may kill them, they shut down until they reach an environment they can live normally in again. They're able to live in this shutdown state for long periods of time. They can survive being released into space for a while for example, an environment that obviously has nothing they require to live and is also exceptionally cold and radiactive. Link to comment Share on other sites More sharing options...
GarethRDR Posted March 31, 2011 Share Posted March 31, 2011 Out of an 8 hour working day, the Understudy spends 3.5 hours on VT and 4 hours on Facebook. Only a matter of time til his employers catch on I'm pretty sure if we plugged a dynamo up his arse we could solve the energy crisis. Link to comment Share on other sites More sharing options...
TheDon Posted March 31, 2011 Share Posted March 31, 2011 what's so scientifically ambiguous about that? The notion that we can't go lower than that. I don't accept the limitation. The limitation is one of definition though. We can't go lower than absolute zero because that is the point where all energy in a system is available for work, where there is zero entropy. It's impossible to get negative entropy, so we really can't get lower than absolute zero. Now if we can get lower than what we class as absolute zero, who knows, afterall some substances still retain entropy at absolute zero, but if we can, it'll just mean redefining the level of absolute zero. I've always not understood the notion that we can't go faster than the speed of light. Obviously we'll never be advanced enough to actually travel that fast. But as I understand it, even if we had somethign powerful enough, we would be physically unable to go faster than the speed of light. It's only a speed, why can't we go more than that? As things speed up they gain mass, the faster something is the higher it's mass, and the more energy needed to move it. As speed approaches the speed of light mass becomes infinite, meaning you'd need infinite energy to accelerate it. The only reason light can reach the speed of light is because it's massless. To travel at the speed of light you'd need to remove all mass from an object. To get it to go faster, you'd need it to have negative mass. I wouldn't want to travel at faster than the speed of light though, by the time you've seen something you've already hit it. Not a good position to be in! Link to comment Share on other sites More sharing options...
legov Posted March 31, 2011 Share Posted March 31, 2011 Entropy? I've forgotten more about my chemistry and physics lessons back in the day than I thought. Link to comment Share on other sites More sharing options...
BOF Posted March 31, 2011 Moderator Share Posted March 31, 2011 The limitation is one of definition though. We can't go lower than absolute zero because that is the point where all energy in a system is available for work, where there is zero entropy. It's impossible to get negative entropy, so we really can't get lower than absolute zero. Now if we can get lower than what we class as absolute zero, who knows, afterall some substances still retain entropy at absolute zero, but if we can, it'll just mean redefining the level of absolute zero. Yes, meaning that the current definition would be wrong. Which is what I'm saying. Link to comment Share on other sites More sharing options...
BOF Posted March 31, 2011 Moderator Share Posted March 31, 2011 I wouldn't want to travel at faster than the speed of light though, by the time you've seen something you've already hit it.I know some women drivers who must travel faster than the speed of light so. *runs for cover* Link to comment Share on other sites More sharing options...
TheDon Posted March 31, 2011 Share Posted March 31, 2011 The limitation is one of definition though. We can't go lower than absolute zero because that is the point where all energy in a system is available for work, where there is zero entropy. It's impossible to get negative entropy, so we really can't get lower than absolute zero. Now if we can get lower than what we class as absolute zero, who knows, afterall some substances still retain entropy at absolute zero, but if we can, it'll just mean redefining the level of absolute zero. Yes, meaning that the current definition would be wrong. Which is what I'm saying. Not really, the definition is still right (as it's defined by the event, not the number it occurs at) it's just where we think it lies that would be wrong. Link to comment Share on other sites More sharing options...
BOF Posted March 31, 2011 Moderator Share Posted March 31, 2011 Not really, the definition is still right (as it's defined by the event, not the number it occurs at) it's just where we think it lies that would be wrong. Well the definition is an always-moveable arbitrary line that they can move to suit their current understanding so yes the 'definition' will always be right. It's the level that it's at now that I don't agree with i.e. I think we can go lower. The fact they'll just re-move their imaginary line doesn't change that in 10/20/50 years we'll be laughing at where it currently is. Link to comment Share on other sites More sharing options...
TheDon Posted April 1, 2011 Share Posted April 1, 2011 Not really, the definition is still right (as it's defined by the event, not the number it occurs at) it's just where we think it lies that would be wrong. Well the definition is an always-moveable arbitrary line that they can move to suit their current understanding so yes the 'definition' will always be right. It's the level that it's at now that I don't agree with i.e. I think we can go lower. The fact they'll just re-move their imaginary line doesn't change that in 10/20/50 years we'll be laughing at where it currently is. I don't think we'll be laughing too much tbh, we already know that molecules at that temperature aren't still, they still oscillate slightly, so in theory there is more entropy that could be removed (temperature is after all a function of energy and entropy). We're certainly not going to be going much further past where we think it lies, we'd be talking a fraction of a degree maybe at most, and never below the concept of it, because you can't remove any more energy from a system than it being at absolute zero. Incidentally, "negative" temperatures do actually exist, but not in the way you'd assume. Something with a negative temperature is actually hotter than something that is infinitely hot. Try to get your head around that one! Something with a negative temperature has entropy decreasing when adding energy. Link to comment Share on other sites More sharing options...
The_Rev Posted April 19, 2011 Share Posted April 19, 2011 Greenock, a small town in western Scotland is served by no fewer than nine railway stations despite only having a population of about 45000 (which is about half the population of Rugby) Link to comment Share on other sites More sharing options...
legov Posted April 19, 2011 Share Posted April 19, 2011 Also, a "small town" like Greenock would have been considered a pretty **** large city 300 years ago. Link to comment Share on other sites More sharing options...
theunderstudy Posted April 19, 2011 Share Posted April 19, 2011 Greenock is home to Greenock Morton. Link to comment Share on other sites More sharing options...
Stevo985 Posted April 20, 2011 VT Supporter Share Posted April 20, 2011 Jimmy Glass, the goalkeeper who scored a last minute goal to keep Carlisle in the football league about 10 years go and has gone down in Carlisle folklore, is married to Louise Glass. The same Louise Glass who was the subject of the "Did you smash it?" discussion between Jamie Redknapp and Richard Keys. How's that for useless information? Link to comment Share on other sites More sharing options...
legov Posted April 24, 2011 Share Posted April 24, 2011 Certainly a useless and little-known bit of information - my psychiatrist is running as an opposition candidate in my constituency. (election's early next month, fwiw) Link to comment Share on other sites More sharing options...
The_Rev Posted April 24, 2011 Share Posted April 24, 2011 You'd have to be mad to vote for him. Link to comment Share on other sites More sharing options...
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