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Everything posted by J'Dona

  1. The AP reports that he has died. Quoting a source using their brief: LOS ANGELES (AP) -- A person with knowledge of the situation says Jackson died Thursday in a Los Angeles hospital. The person was not authorized to speak publicly and requested anonymity. ...
  2. I can't speak for Oxbridge, but I expect they're at least as good and probably better. Imperial does focus on science, engineering, and medicine (the tiny humanities department was recently cut by 60%), but proportional to funding I don't think they're doing a better job than Oxbridge. Imperial's departments themselves are large, so to a student in science it may start to approach something like a production line, with a lot of material and work tossed onto students' heads but with little continuous assessment or personal feedback, unlike the tutorials system at Oxbridge. So as a student, I'd think that the Oxbridge treatment would rank them "better" in sciences. Having more faculties probably helps on league tables like the Good University Guide in terms of the funding those departments provide. Several years ago there was talk of merging Imperial and UCL to make a "superuniversity" which would surpass Oxbridge and be on the level of Harvard, somehow, by having good departments across the whole range with the funding of both. (It failed as UCL natural scientists rebelled, saying they'd be made redundant.) Maybe Imperial and LSE would have been a better match!
  3. Hmm, I'm surprised that Imperial College's research score isn't a touch higher. After all, the chief reason it has such abysmally low student satisfaction scores is that the administration tends to view it as a research university (or latterly a corporation), to the point that I wonder whether they're aware they have students at all.
  4. Well, I appreciate your comments and I think it's good that you're committed to furthering your understanding in possibly new ways. Toward that, you surely must intent to further study the mathematics and science involved, which would assuredly expand a sense of wonder by opening profound new theories and understanding to you. At the very least, it would aid your exploratory thinking by allowing you to extend your hypotheses and determine their consequences. I'm sure you can see that this would at least allow you continue the discussion by responding to many of the points raised in this thread, such as in my earlier posts, and not those that were off-topic as in my previous post, which I had asked that you did not address exclusively.
  5. Me neither. I just find that following a Möbius path of logic and explaining to the OP where it got us is good practice, even if they don't listen.
  6. throng, it should be clear that to convey an abstract, mathematical idea as you describe, you need to use mathematics. Your statements about a "finite space constant" are explicit and have derivable consequences, which are what I explored in my last post. However, you ignored my post and commented on the ones astride it, which frankly given the simplicity of the argument in it (and the ease with which you could destroy it if it makes false assumptions) doesn't speak well of your understanding of the mathematics. Please address the points made in it—not just this post—and provide a mathematical description of what you're trying to say so we can understand you.
  7. As Mokele and iNow said, I think it's quite educational, and sometimes it's good practice. Responding to posts in Pseudoscience can help people learn to construct their posts in a logical manner and think analytically and critically about the arguments at a level that they'd be embarassed to display in the main subforums (or perhaps that's just me...?).
  8. Okay, I had thought this might be the case but assumed that you meant some ratio between a point (with an assumed infinitesimal but non-zero width in a given dimension) and the size of the Universe (in that same dimension). Of course, a point is that which has no part, and so has zero width, so we aren't really talking about points, but infinitesimal scales. I take it that when you imply point E may be everywhere, you mean that we can choose a value anywhere, so that a distance between it and a point A is still well defined. You say that any finite distance as compared to an infinitesimal object (which you call a point), that is, the distance V between a point A and a point E is a "finite constant" which defines a relationship between them, so that even if the physical distance changes, relative to an infinite Universe the value of V is constant. Scaling the position of E up to infinity (as should be acceptable for the infinite space you assert in the first post), we would presumably have an object of finite, non-infinitesimal size at A. In that case the "finite constant" V doesn't obey normal rules of algebra (as described my last post), sort of like dividing by zero or, in this case, multiplying by infinity. V is undefined because the infinity can absorb any definite factor (to become infinity again) so that halving the constant and doubling the infinity to leave the finite distance on the right-hand side fixed is the same as halving the constant and doing nothing to the infinity, while still equating to unity. So the "finite constant" is neither necessarily constant nor defined. Not to belabour the point, but to be completely clear, let us define [math]V[/math] such that [math]V = \frac{d_A}{d_E} \quad \implies\quad d_E \cdot V = d_A[/math], where [math]d_A[/math] is the physical size (at A) and [math]d_E[/math] is the physical distance (to E). (If this is incorrect, do tell, but based on the minimal description provided this is the only case I can see which preserves a constant [math]V[/math] for finite physical distances and scales.) So extending to the case where [math]d_E \to \infty[/math] and [math]d_A \to 1[/math], which must be acceptable for a Universe of infinite size as you assert, we have [math]\infty \cdot V = 1[/math] . But infinity is one of those quantities (along with zero) that breaks normal algebraic rules, so that multiplying by it leads to contradictions, due to odd properties like [math]2 \cdot \infty = \infty[/math]. Specifically, we may obtain [math]\infty \cdot 2 \cdot \frac{V}{2} = 1 = \infty \cdot \frac{V}{2} = \infty \cdot V[/math], from which we can not just divide by infinity and claim that [math]V[/math] is equal to half of itself (as infinity divided by infinity is undefined, otherwise from above we'd have 2 = 1 and thus that I am the pope), but we can still see that the solution satisfying the condition is not unique, so that [math]V[/math] is not well defined. The resolution of this is to accept that there exists (at least not in this form) no definite constant which can reduce an infinity to a finite value, and so that your concept of a finite space constant V is not useful. Since a lot of the confusion here seems to stem from your use of certain words (as the multiple requests for you to define certain terms suggests), you should be more careful in referring to "points", which have no geometrical dimension, when you really mean an infinitesimal quanity, which has dimension. It also changes the algebraic properties of the quantities you are talking about (e.g. an infinitesimal divided by an infinitesimal may be, say, a perfectly well-defined derivative, whereas zero divided by zero is undefined). It's extremely important that you use the corrent terms and definitions when describing something, particularly in mathematics, or you'll end up wasting a lot of people's time as they try to understand something other than what you meant to explain.
  9. Hi throng. As you've restated yourself a number of times I hope you don't mind if I use a contracted version of one (post #5) to frame my question: Possibly I'm being very stupid but it sounds to me like you're asserting that there exists a "finite constant" [math]n[/math] such that [math]\infty \cdot n = 1' date='[/math'] where [math]n[/math] is definite, i.e. not undefined, but not quantifiable, i.e. undefined. [i have assumed for this that relative to the Universe in any dimension the size of a point may be normalised to unity, as I assume you did not mean to suggest that [math]\infty \cdot n = 0[/math] for definite values of [math]n[/math]. This is, of course, an assumption which should be justified.] Unless I've interpreted your use of these words incorrectly, I'm afraid this does not appear to be a significant contribution to science.
  10. You wouldn't happen to know (I can't find it in the linked outline) the number of times they repeated these five-minute tests? (Not that the results are unbelievable; I'm just trying to be critical.) With 53 male and 58 female participants in the second study, the noted decline in cognitive performance in men (~40 ms increased time on average) after mixed-sex interactions was only around several percent. If they didn't repeat the experiment many times, this isn't very reliable, and even if they did with such a small sample size they might just have particular people who were "slower" in those situations, such that it wasn't the case generally. Also, did these students submit their orientations before the study? I don't have the full set of data points, but the S.D. of the female mixed-sex interactions was 73 ms, versus 45 ms for the males, the difference between which is about the difference in the means themselves. So technically for normal distributions about the given means we'd expect more females at times above a little over one S.D. (~680 ms). (And even if not, with a S.D. that high presumably some females were affected and some were less so, so that the final statement that females were not affected by the different situations isn't really as general as implied, particularly if to give that mean and S.D. a fair number responded by being quicker.)
  11. However, it is one of their stated goals to provide a foundation for whole-brain simulations, which is clearly applicable to strong AI (although far beyond the scope of their research). Their research at least shows that real-time simulation of a macroscopic portion of a brain (a 0.5mm cubed neocortical column) is possible, and by doing so it may assist in developing software (like NuPIC) to simulate the same process without as much computational power.
  12. Well, the Blue Brain project recently completed its first phase where they used a Blue Gene supercomputer cluster to simulate an entire neocortical column in real time, with results matching those of actual observations. If quantum computers with capabilities along these lines are developed soon enough (as this sort of parallel processing is presumably what they're theretically best at), then as the model already exists, by scaling up the project (with multiple NCCs) we might see progress rather quickly, given perhaps some sort of business angel like Paul Allen to bankroll the research. But by 2029? I think that if they have a coherent model of any sort by then, then tied with existing AI software it might be intelligent enough to persuade most humans, but still be recognisable, so I think maybe one more decade beyond that would be needed to be sure. (20 years isn't very long from now!) I'll say though, that while I'm actually trying to get into quantum computing for explicitly this purpose (creating strong AI), it sure isn't for the trans-human, futurist slant of exponentially increasing intelligence to the point of obsolescing the human race that Mr. Kurzweil seems to promote.
  13. As far as I'm aware, VSL theories (or at least the one proposed by Albrecht-Magueijo) allow for variation in the fine-structure constant [math]\alpha[/math] by keeping Planck's constant and other constants fixed. Supposedly this can help to explain certain erroneous measurements from quasars far back in the Universe's history, which would be explained by a lower value of [math]\alpha[/math] at the time. They talk about varying [math]c[/math] versus varying [math]\hbar[/math] (without any real math) on the first couple pages of their paper here, though this may not display for you: http://arxiv.org/PS_cache/astro-ph/pdf/9811/9811018v2.pdf Other than quasars and apparently solving a few other problems in cosmology, I don't know if VSL theories are fully constistent with observations. A change in [math]\alpha[/math] should affect the probabilities of certain products in nucleosynthesis in a way that might predict different proportions of elements in the Universe (and might have [math]c[/math] varying significantly during this period), even though the proportions are very well understood by existing theories. I'd also be curious if anyone else has heard more about these theories and if they're dead or not (possibly Martin, as he tends to be deep in the know?).
  14. Well ... http://shortpacked.com/d/20050722.html I assume you weren't being entirely serious, or you wouldn't have quoted a comedy.
  15. I guess I had two pretty good moments today: 1) Learning that just about every student in my department loathes the senior tutor (with stories as to why even more disturbing than my own) when I thought it was just me. 2) First opening last year's GR exam (the only one our lecturer has written so far) to discover that he copies problem sheet questions, such that I could finish one worth 1/6th of the paper in two minutes.
  16. Perhaps you could post some more specific details of what vitamins and dosages these megadoses involve, so that posters will have an idea why your approach apparently has different results from most other vitamin users? (I'm assuming you aren't averse to this, as otherwise you wouldn't have posted on a forum in the first place, and if you are already being "checked out" by government doctors and scientists then you've likely already done that.) I ask because you surely can't mean just straight multivitamin pills, but rather a very concentrated diet targeting specific vitamins and nutrients. But there must be some element of multivitamins or you wouldn't have brought it up, and as at least one study (with N = 232606, anyway) claims a link between some multivitamins and increased mortality, I'm curious if you mean there is a different way to use them.
  17. Thanks, Martin. It's very fair to point out that the questions raised cannot really be answered without a complete theoretical description of the system ... that, coupled with the perhaps non-meaningful description that an infinite scale factor introduces, is something that I should have made clear, so I couldn't possibly expect an answer on every point. However, hopefully I'll still be in the field in ten years' time (even if possibly moving away from my present emphasis on particle cosmology and toward quantum computing) and will be able to necro this post and fully disprove it (if [math]\omega[/math] is somehow still within range!). I haven't seen Penrose's talk so I shall watch that now, thanks for the link! If there are any aspects of this which aren't affected by the unknown dark energy equations or similar, anyone please feel free to comment if there's something to learn there.
  18. Hey, this is my first thread in a while, by which time I hope I'm now able to ask actually interesting questions, even if they are still pointless. (There's a summary at the end if you want to tear some speculations up as soon as possible.) About a year ago when reading the Wikipedia article on the Big Rip scenario, I had a question as to what might happen at very late times. I wrote it up with, and I must stress this here, the explicit intention of proving it wrong and so learning from the endeavour; I expect it is entirely false and without merit, but I do not yet have sufficient knowledge, or have not yet considered it in the right way, to absolutely prove it wrong in an ironclad explanation. So, I'm posting it here to see if anyone else can, or even better, can point me in the right direction so that I can disprove it. With any luck, I'll be doing a theoretical physics MSc next year so that by the end of that I would be able to tear it down in seconds, but if anyone wants to give a few hints on the way I thought it would be an interesting topic. Here we go, I'll try to make it entertaining ... Motivation: Assume that the Universe ends in a Big Rip scenario, i.e. in the acceleration equation, [math] \frac{\ddot a}{a} = -\frac{\rho\left( 1 + 3\omega \right)}{6M^2_{Pl}}\text{,} [/math] we have [math]\omega < -1[/math]. The result is a Universe whose scale factor [math]a[/math] reaches infinity at a finite time. (This is estimated to be around some 50 billion years from now. A value of [math]\omega < -1[/math] is not inconsistent with current observations, but it's very unlikely.) Hypotheses: In this scenario, as [math]t \rightarrow t_{end} = t(a = \infty)[/math], stars will expand away from one another, then planets from their stars, the Earth will break up, etc. However, this would continue until the consituent quarks in hadrons are forced apart until they are free. (It may be more energetically favourable, while being pulled apart, to split into new quarks, but at the actual time [math]t_{end}[/math] these distances would still be infinite.) If we assume the conditions then are such that free quarks are forbidden (the entire observable Universe to each quark being that quark alone), then free quarks may still be forbidden. In this case, we first hypothesise that the free quarks decay (1). But with an infinite scale factor, we cannot really talk about a multiple-body decay as there is no meaningful notion for the amount of separation between two bodies. In fact, even the definion of a point particle may be in confusion if "that which has no part" is scaled by an infinite amount, which I'm not even going to comment on. The only meaningful form of decay I can imagine for something which either occupies one points or all points in space, is that the energy contributes to a scalar field (2) or similar, i.e., all points in space. This would occur at [math]t_{end}[/math] for every particle. However (and THIS is the point where we toss local causilty out the window), to maintain CPT conservation in the Universe (or just electric charge, colour, lepton number, etc.) we would need pretty much every other fundamental particle to decay as well, all contributing to a scalar field. (Photons, or any particles, really, we toss in regardless because quantum fluctuations or uncertainty in any direction might spread it over a distance which is scaled to infinity, and so on. It should be clear this is a particularly weak part of the description. This has the effect of ensuring that the total energy in the field at the end of the Universe is the same as that at the start, as all the random photons which had lead to an increase in entropy were still flying out in space) Finally, just for the hell of it, we hypothesise that this scalar field has a potential sufficient for cosmological inflation (3), and invoke the Poincaré recurrence theorem or some deus ex machina to claim that the scale factor resets (whereupon we have finally transitioned to pure science fiction). The end result is a Universe with the same energy as before the Big Bang, with the same conditions, and things happen all over again. Criticisms: If the parenthetical statements weren't indicative enough, I've thought about the problems with this already and produced a list. Specifically I am aware of the following assumptions/issues which I imagine are enough to break the hypothesis several times over (sorted only by how important they are to the basic hypotheses, not flagrant violation of physics). I imagine the most interesting, however, will be something not listed here: 1. Critical Free quarks decay (IFAIK this was not true at the GUT scale in the Big Bang, so maybe not here) Energy contributes to scalar field (given theories that the inflaton field for our Universe was generated by the convergence of two higher-dimension branes, I don't yet know enough to comment on this) Scalar field has form of inflation potential (unless a scalar field does by definition?) 2. Serious Reset of scale factor (not that a zero scale factor is any more meaningful than an infinite scale factor ...) Quarks "free" before [math]t_{end}[/math] (so scalar field sets up over a time, possibly longer than time needed for slow-roll or enough to affect number of e-foldings substantially and leave an effect on the CMB of the next Universe) Rest of Universe "knows" quarks decay (and subsequently decay themselves to conserve charges, which seems to VIOLATE CAUSALITY) Infinite stretching of a sacalr field (even if otherwise homogeneous, is a scalar field in this case still meaningful?) 3. Irritant Entropy (gets reset, and as philosophically pleasing as that sounds, the Universe is destroyed on the way so I have no personal investment in whether this is actually so) Loss of energy (if entropy is not reset because, e.g., radiated photons do not contribute to the field, there wold be a loss of energy in each "permutation") I hope anyone bothering to read all this has had fun. I hope someone can disprove this theory because if someone who was, at the time, a 3rd-year undergraduate can come up with this and it isn't false entirely, modern physics is in a poor state. If someone replies on a point and I subsequently question their explanation, it's probably because I want to understand it better! But really, the best responses would be ones which allow me to find the answers for myself, so that I can best learn. Summary (tl;dr): Big Rip scenario [math]\implies[/math] Universe is stretched by infinity in a finite time. Even quarks in hadrons split apart. Hypotheses: Free quarks decay Energy contributes to a scalar field Field has potential like in inflation The Big Bang happens again and everyone does the macarena. (Please disprove or help me disprove this so that I can learn.)
  19. Perhaps I could find the answer myself with a little more investigation or imagination, but in this case I'd invite anyone to illuminate me ... What is the practical point of cold fusion if it doesn't put out sufficient thermal energy to drive a generator of meaningful size? If the energy liberated did indeed manifest as excess heat in the sample (e.g. in claims of bubble implosions or similar), surely this just shows that it provides no alternative method to generate power? In which case, given a fair lack of many other applications (beyond a very limited range of enriching certain elements), why does cold fusion elicit such excitement?
  20. Wow, looking back at my earlier intro post actually makes me want to let blood. I guess it's a healthy reminder of what I used to be like. Anyway, I haven't posted regularly for about four years, mostly due to my finally realising that I basically didn't know anything, and that as such I shouldn't talk about it. I still don't, really, but at least now I better understand the bounds of my knowledge, so with my small but now firm basis I may actually be cabable of rational discourse. So it won't be much (it still takes hours to write a long, coherent post) but I'd like to start practicing again. Since my last major activity (pre-university), I'm now in the fourth year of my Physics MSci and hope to do an MSc next year to shift my emphasis to theory, then go for a doctorate after that. I'll try to post in the phsyics section if I think I can be useful.
  21. Ooh, all those neat Greys! I don't get what's funny? Personally I think the shoulder pads in #9 look quite dapper! [/iC]
  22. Don't forget, many extrasolar planets being discovering now (most in fact) break this trend. Some planets with many times the mass of Jupiter have been found so close to their star and moving so quickly that they complete an orbit in a matter of days, like this one. You originally say: "Common sense tells me that the further from the Sun, the larger a planet can be." Do you mean this in that there is more space for it to fit without interfering with other planets? Because aside from that effect, which is usually negligable (but still possible as in the case of Jupiter and the asteroid belt), there isn't much of a relationship at all: small bodies can exist anywhere from very close (like Mercury) to beyond the orbit of Neptune, and gas giants can be extremely close, middle-of-the-range, or so far and so massive that they undergo nuclear fusion and we have a binary star system. We could try to deduce trends of planet formation based upon our own solar system, but as soon as other systems enter the frey those predictions would probably fall apart. Another question you might ask is: if the distribution of dust and gas in the proto-solar system was smooth and exactly proportionalo to distance from the sun, so that we could make assumptions based upon it alone, then why did planets form at all?
  23. Oh snap, now the disenfranchised astronomers who weren't able/willing to vote on the final resolution (where only some 424 out of about 2500 astronomers attended) are having a backlash against the IAU. As Dr. Alan Stern, head of NASA's New Horizons mission, points out, the resolution's definition for "planet" isn't consistent with those considered one now and excludes Earth, Mars, Jupiter, and Neptune, the first three on grounds of various asteroids which cross or occupy their orbits and in the latter case because of Pluto. As it is, any astronomer should have been aware of these asteroids and I don't think there's an excuse for a scientific definition to even leave such things under debate.
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