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Fred56

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Everything posted by Fred56

  1. Maybe it would be safer to say something like "infinity - infinity can be zero, if the infinities have the same cardinality (size)"? Where is this guy? Infinity is something that can never be reached, by definition. When Mathematicians say a value “approaches” infinity, this is understood to mean that some variable, either a real or natural number, can always increase. It doesn't “become” infinite but the concept that it is able to “approach” an infinite size is easy to understand. This concept of a value that can be arbitrarily large and approach the infinite, is the key to understanding a lot of other mathematical ideas. Saying something like: “an infinite number”, or “an infinite value”, seems to run into problems: a number can not “be” infinite and infinity has no (determinable) value. We are able to conceive the infinite in terms of some process, some counting or ordering which can continue indefinitely, but we cannot conceive the infinite. This isn't a big problem, because mathematics lets us deal with it by assuming that, while it is "attainable" in some sense, it doesn't need to actually be “attained”. Saying: “an infinite set is countable” sounds odd too, but it just means that there is some ordering, like a series or progression, which maps to the natural numbers. There is no such ordering available to the set of real numbers, and this set is said to be uncountable. Saying: "infinities can not have any value, but can have size", sounds a bit paradoxical, except that "size" can't be defined any further than being larger, smaller, or equal, in terms of infinites. So "size" is a property of infinities which can only be defined as relative (to some other infinity).
  2. And science is firmly ensconced in...?
  3. OK found a couple. The team is Camp & Tung and it's based on an analysis of >50 yrs of data. http://www.upi.com/NewsTrack/Science/2007/08/02/math_used_in_new_climate_change_assessment/3629/ http://scienceandpublicpolicy.org/sppi_originals/the_unruly_sunne_cannot_be_ruled_out_as_a_cause_of_recent_climate_variation.html And here's some of the content: 1. 2. "Though Lockwood and Frohlich present data indicating no correlation between solar and temperature variability, such correlations have been recently reported. Fig. 5, for instance, documents an interesting new result by Camp and Tung (2007) demonstrating a correlation between the 11-year solar activity cycles and the global surface temperature variations during more than half a century between 1959 to 2004: "Since the [solar] forcing is global, theoretically one should expect a global-scale response. When globally and annually averaged and detrended, but otherwise unprocessed, the surface air temperature since 1959 (when the modern radiosonde network was established) is seen in [Fig. 5] to have an interannual variation of about 0.2ºK, somewhat positively correlated with the solar cycle, although the signal also contains a higher frequency (of 3-5 year period) variation of comparable magnitude, possibly due to El Niño-Southern Oscillation (ENSO). What is surprising is that a solar-cycle signal is already apparent in this "raw" data. An isospectral Monte-Carlo test shows that the correlation coefficient, ρ = 0.47, between the global temperature and the TSI is statistically significant at 98.4% confidence level. This is obtained without any filtering of the global mean signal, and gives confidence that the solar signal is not an artifact of our filtering to be presented below." Fig. 5 Half a century of correlation between solar activity (TSI) and detrended global mean surface air temperature (T). From Camp and Tung (2007). The availability of scientific results such as those of Camp and Tung suggests that Lockwood and Frohlich have founded their conclusion upon selected data, and that conclusions other than theirs are possible."
  4. Um, just a comment: 1. There aren't so many climate scientists posting comments and/or analysis on SFN (except by proxy). 2. There aren't many posters to SFN who really know more about climate than climate scientists. 3. The scientists admit there are lots of things they still don't know or understand all that well about climate. That said, there is no real problem with batting around opinion and speculation, as long as it is understood as such. I don't think SFN is going to nail this issue (for the scientific community) any time soon. But the scientists seem to be saying it isn't going to go away, either. So there is plenty of room left for debate and discussion. Isn't that nice?
  5. Ahem. Sorry to detract from the spiral discussion, but: "Happens", "see", "move", "evidence" are all semantics that describe human experience. This is due to our brains not some fundamental principle. This sounds like semantic hair-splitting, sorry.
  6. OK. Ready? Here we go then: This is ok to say, but on analysis, the first question has to be: where is the event created? It makes more sense to say “when” the event is created. Except then you're saying that time “times” events. The old circular definition problem. Here, your argument runs into some semantic difficulty. “Proceed” and “goes the other way” imply movement of some kind. Again, the circular definition appears: you are saying something like: “events move through time”. But you're still only saying “time is what times the event” On the first page of this thread I quoted something from another website about energy. This says that the concept of energy “flowing” or moving is just a concept, nothing more. But where is it being recorded? So God does keep a backup (of the universe)? Note: before when I posted this: it occurred to me that: Well, we can if we use a couple of stopwatches. Except that these are “representative” of time. They don't have little “time tanks” inside and we can't get any of this time stuff out of one of them. And: Things like rulers, watches, thermometers, pressure transducers, indeed all of the various instruments we make for such a purpose, are all used to “assess” or “manipulate” our concept of change and its measurement. This concept, or experience of change in the world around us, is based entirely on our own internal mechanisms of change. We use change to measure change. There seems to be no easy way around this apparent conundrum. Each of the instruments is ultimately an extension of our concept of such change. We know we can't get the temperature out of a thermometer and put it somewhere (say for later use), or grab a few metres of distance. We only have a “representation” of these things. This representation only ever has a “mental” existence. Reality is memory.
  7. Al Gore? Maybe in some distant age they will find something like this about him (this is a joke btw): Then did Elgor descend from the mountain and spake he unto the people, saying: "Verily hast thee sinned and done evil, and hast thee caused great sorrow, and now wilt the very earth rise up, and destroy thee! She will send floods, and great storms, and plagues and pestilence. The hour of thy repentance is passed!" And many quailed, and great fear was among them, but some said: "And who art thou, prophet? Howbeit thou dost pretend to tell us what will be? What authority or stricture hast thou against us? Begone!" and they did castigate him, and cast him out into the desert. But Elgor gathered about him his followers, and succour was given unto him. Having respite from the unbelievers, Elgor came unto the Citadel and there was he brought before Jeymes the Unbeliever, and answered unto him, saying: "Liar and hypocrite! Long hast thou sought to deceive the people and conceal the Truth. Verily art thou damned!" but did the Great Unbeliever stop up his own ears, and wail and gnash his teeth, and a great smoke issued forth from his nostrils. But Elgor quailed not, and strode forth and did smite the Unbeliever, and he fell upon the ground, and a great shaking of the earth was felt by all the people. And did Elgor triumph over Jeymes the Unbeliever and a great noise and rumour went out amongst the people and they spake each unto the other saying: "Who is this Elgor? Is he in truth a prophet? Howbeit he dwellest in such a great an house, and hast he many great and costly chariots and wagons?" and many would not believe...
  8. brodix: I think your post is quite good, but can see one or two philosophical, and semantic, problems. Since these have been covered (sort of) in this thread already I can leave it at that, or would you like to haggle over, I mean discuss, some of the finer points?
  9. Don't these things get sorted out, like, posthumously, mostly, or even somewhat?
  10. I see. The guests are all isomorphic discrete sets, and the rooms are the ordinal mapping? Or something like that? Please do keep up the comments. This getting more interesting (as I said, I've only done a bit of 3rd yr math, the furthest I got was transforms in the s-domain, not much set theory).
  11. Maybe 'cause no-one really understands it yet.
  12. Right. There are plenty of experts who claim to know all about what makes the Earth and other planets orbit the Sun, and others who claim to be able to build very fast computers, and others who claim to be able to make wondrous devices constructed of extremely small wires and connections (I think they call these things "chips"). Even others who claim all kinds of strange things like being able to store a pulse of laser light in a small cloud of super-cold atoms. Maybe they are all just kidding though.
  13. On that note (and with apologies to members of the GWB Admiration Society):
  14. Um, I don't have a Chem degree, but I think you will find that such a thing simply will not happen. There is way too much free energy in the liquid water, which keeps the ions "in solution", more or less permanently. Overcoming this would require a really, really fast centrifuge. You need to effect some change in the system for ions to precipitate. If you put it in a freezer, it would cause a gradual increase, as it froze, of concentration of the salt. The water turns to ice, and the salt solution doesn't, but collects in concentrated "pockets" within the ice. Eventually it precipitates but thawing out the ice will cause it to all go back into solution. This "precipitation by freezing" works with compounds that have a low solubility, though (so the precipitate remains at the bottom of the container after re-melting).
  15. How well do you think any of us (here in the "civilised" world) understands a country like Iran? You are aware that the Pres. actually has little power? That his status and position are largely dependent on both popular support and support from religious leaders? That he is essentially trying to score brownie points when he says some of the things he says? That his statements, and the responses from those Western governments who supply his fire with more fuel, are just a war of words because he has no real power?
  16. Maybe life is one of those complicated things that is just hard to define in a succinct way. It does seem difficult to pin some sort of "equation" on to, it just sort of squirms out of the way each time. We are now at the beginnings of what might become a very important mathematical pursuit: complexity theory. There are many complex systems around (our planet and its climate, for example). The many forms of life are all examples of complex systems. This branch of Math is still quite "immature", so we have a ways to go before an "equation of life" appears on any blackboard.
  17. Well, I'm glad we cleared that one up.
  18. Does anyone know how to conjugate the Latin verb "descere"? I know it's from the 3rd group, and I know it's a replicative. I just get a bit confused with it. Does the stem only change to the replicative form in the perfect tense or what?
  19. "A bigger forcing" doesn't imply that the sun is getting hotter. I'm referring to the variation in solar activity during the 11-year cycle. This variation has, until now, been believed to have no, or an insignificant, effect. The new research appears to indicate that there could be 0.2 degrees of extra forcing at the top of the cycle. This should be borne out, or not, by the next cycle (which starts real soon). Apparently they will be able to calibrate the measurements better, or something. If you're really interested, I could try to find a good link to this.
  20. Do you have any theories about why Antarctica has done this? Or are you aware of any scientific ones? This is often put forward by some people as supporting the argument that it's all natural variation ("some places warm, others cool", the Earth "does this all the time", and so on).
  21. Thanks for all that. It seems to me that an understanding of "the infinite" is fraught with all sorts of problems and difficulties (especially language). You first need to understand such concepts as "a real value", "a variable", and "regression" and so on. The concept of "taking a limit" was explained to me, I recall, in a similar way to the explanation I used above. That the hypotenuse's slope (sorry should have specified that), approaches the slope of the curve at some point. This point doesn't have to be "reached", the triangle just has to be small enough and it is easy to "extend" this idea of "small enough" to "small as possible", or "infinitisemally small", except you don't have to get that far, just accept that it is logically possible. There are semantic difficulties when using "ordinary" language that require a more formal grammar, which is all that number and set theory I need to get my head around. My earlier posts on all this have factual errors, I see. In Hilbert's hotel, are the guests all natural numbers, or have I jumped to an incorrect conclusion? What if they are all infinite series with non-finite results (values)? Or infinities?
  22. So "our" part of the world, the one that invades countries and spends gazillions on weapons and navies and fleets of bombers, and lets things like Darfur keep on keeping on and does bugger-all about a lot of "bad" things (Burma, Zimbabwe, AIDS) in general is, thank God, free from all that stuff?
  23. Infinity can be something very large, so large it is uncountable, or something very small, as small as you like, or infinitisemally small. Newton's concept of infinitisemal quantities was the key to understanding the dynamics of motion. Pythagoras' relation between the sides of a right triangle holds for very small triangles, so when approximating the slope of some curve, any triangle can be made arbitrarily small, even "infinitely" small. Once this is understood, it can be seen that as the triangle gets smaller, the hypotenuse's slope “approaches” the slope of the curve. From the triangle's point of view, the curve “approaches” a straight line. The curvature “disappears”. The process of shrinking the triangle's dimensions does not have to complete. Because we know it can be made arbitrarily small, we also know that this regression doesn't actually need to reach any “destination”, we only need to understand that it can be made as small as we like, until it approaches the “size” of some point of interest. And this arbitrary smallness will mean that the hypotenuse's slope will, at some remove, be equal to the slope of the curve at that point. The triangle has a fixed, but near infinitely small, size.
  24. Sorry, I read the problem wrong. But since it says the ball is thrown, presumably it then has some undefined velocity? Wouldn't it just be easier to assume it will reach vt before reaching the point of intersection? Unless it really is a trick question. Nah, that's a bunch of horseshite. 15 meters is way too small a distance to reach terminal v. So the only other assumption (that I think makes any sense) is that ball 2 is "dropped" from a height of 15m. That sounds more like it. Maybe I shouldn't have had that smoke.
  25. One of the most ridiculous arguments I keep hearing about Iran's "supposed" (but probably very likely) pursuit of nuclear weapons technology, is that Ahmedinejad has vowed to drop the very first one they build on Tel-Aviv, or words to that effect. But this would be both a very improbable and very irrational act on Iran's behalf. Not only because Ahmed does not actually have his finger on any button(s), but because it is fairly unlikely that the mullahs are prepared, despite all their thundering, to invite annihilation of their country from the inevitable Israeli/US retaliation. If it is such a dangerous proposition to allow some country, branded part of an axis of evil no less, access to NWT, why wasn't Nth Korea prevented from developing the bomb, and why hasn't Kim Jong-il dropped one of them on his Southern enemy?
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