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5614

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Everything posted by 5614

  1. X-rays require a lot more energy to produce. Also I don't think an x-ray "laser" could be made, because the energies involved are too high for electrons to produce by losing energy (an electron with that much energy would just escape the atom it is bonded to). If you ever go for an x-ray (a medical one) there's a whole load of heavy, energy consuming, machinery behind it. In nearly all (all?) cases there's an electron accelerator, which then collides with a metal target, producing the x-rays. Having a whole electron accelerator up in space isn't very practical (size, energy consumption, maintenance etc.) and also I'm not sure if focusing the x-ray beam is possible. In medical applications you can focus the beam very accurately, but that is at a close distance range. Lasers are good for shooting down missiles etc. because they produce a very fine energy beam that doesn't spread out much. An x-ray source (which can't be laser based) would probably spread out too much to be of any use, not that it is even practical ignoring this!
  2. Zephir: you're fighting an uphill battle, to state the obvious. The aether is a long discussed topic, for hundreds of years in fact, but we are finally quite certain that the topic has been settled and there is no aether. Look at the MM experiment, relativity and the likes and it soon becomes quite apparent that there is no aether. On top of this things like Maxwell's equation have been so thoroughly tested they each of the 4 equations are justified in being called Laws. If you come along and try to present any theory that differs from these you are going to need very very solid evidence against the current theories, because they have passed every test imaginable, and have been scrutinised from every angle, and still passed. If you tell us they're wrong we're simply not going to believe you unless you have some real solid and convincing evidence. It takes a long time for new concepts in physics to be accepted, look at the paper to Nobel prize time period, or at any big turning point in physics. Only if you can really present your theory and convince others you are correct, and stand up under theoretical and mathematical scrutiny will your theory ever be taken seriously. Well it sure sounds complicated enough to be classified as real physics!
  3. "Traditional" quantum teleportation uses entanglement, through this process only information about the system (more specifically a quantum state) is transferred. I've also read about this teleportation that uses BEC (Bose-Einstein condensates). This method, roughly speaking, takes a collection of atoms and places them by a BEC, the atoms will then release energy so they can collapse down an energy level and become part of the BEC. This energy is in the form of photons, and can be collected and sent down a fibre optical cable. Thus information about the number of atoms that collapsed to join the BEC can be transmitted. But this is still "only" information, and more specifically it is the information which tells you about the number of atoms that joined the BEC. No matter is teleported anywhere, only information about the system is transmitted. One method of quantum teleportation transfers a quantum state using entanglement, and one measures the number of atoms collapsing in to a BEC. Both forms of quantum teleportation are quite different, in terms of method, but they both transfer information only, and not matter.
  4. I don't know whether that is a threat, or you being polite and informing us, or just a general way of bumping your thread... but regardless: I don't know exactly what your current question is, seemingly your original post has been completely answered, so from your post #9 I see this question: Wrong. I assume you know that gravity causes space-time to bend, it is important to appreciate that it is the very "fabric" of space-time that is bending. Light, as we know, travels in straight lines. But what is a "straight" line in a bendy (non-Euclidian) 3D system? We can define "straight" as the shortest distance between two points. Combining my previous 2 paragraphs: when light travels in a region of bent (due to gravity) space-time, it must follow the shortest path between any two points. This shortest path follows the bent contours of space-time. So light may seem to bend, but in reality it is merely following the contours of space-time, and thus travelling in a straight line, where "straight" is defined in the non-Euclidian space-time system. I hope this answers your question. If you have anything else just ask, there are many people here who are qualified and knowledgeable enough to answer almost any answerable question you throw at us (this is not a challenge!).
  5. That's ok. You said: What Klaynos is saying is that from Maxwell's equation you get a single (i.e. constant) wave speed, that is, the speed of light. Whereas when you do similar mathematics for water waves you do not get a single/constant speed, because waves can travel on water at any speed (within reason).
  6. Now I haven't followed all of your thread, but from Maxwell's equations: [math]c=\frac{1}{\sqrt{\mu_0 \epsilon_0}}[/math] [edit] oops, I opened the thread but then didn't respond for a while, yourdad's post wasn't there when I opened the thread! ikes, that was 10mins ago! Ah well. And yeah, like he said, how does your theory explain the MM experi?
  7. 5614

    Expelled!

    ha, that's just ridiculous! To be expelled, because of your views, from a film that tries to talk-down exclusion based on views. And it's a film that he starred in. And they didn't seem to notice Dawkins! Just stupid! Myers and Dawkins having a chat about the whole thing, here: http://scienceblogs.com/gregladen/2008/03/myers_and_dawkins_speak_out_on.php although it's pretty much all repeated in blogs and Dawkin's article, so if you've read them you won't gain much from the video.
  8. haha, that's pretty good too! I just spent 30mins completing the demo, I think it was a lot more challenging than the Crayola physics one. It was interesting how most of the levels were quite obvious, at least conceptually, to me, but there was 1 that really confused me for a while! And it's quite amusing when you do something really clever, but then one of the ropes snap, then the whole thing falls apart under its own weight! It's quite a bit more advanced, physically, than the Crayola one. Mind the Crayola one was completed in a week, and they're quite different games, so it's probably a bit unfair to directly compare. I recall playing a game similar to that Armidillo one a long long time ago. Meh, maybe it was the same game! Anyhow, if people (don't have to be physicists!) have <30mins to spare, go download/instal/play the demo. Official site: http://www.armadillorun.com/demo/
  9. And undo the catastrophic, but luckily reversible, damage he/she/it did! I'm panicking!! Anyhow, it still only links to a maths tutorial page, we need a GUT forum section then. Maybe that would also encourage people to participate. Ha, true! But by the time an interview gets put up everyone will have gotten bored of clicking on the link, if the Interview button only appeared when there was a new interview, and only stayed there for 2 or 3 weeks, then it would be exciting! Eh!? Now there's a gooood boy! *woof*
  10. Why has the "Forums" link been cryptically renamed "Community"? What does GUTs stand for if it only links to the maths tutorial section? And do we really need a link at the top to that section? (especially, but not only, because it is quite small at the moment) If it were for all tutorials then maybe a link at the top would be one thing, but does everyone need a link to maths tutorials? Finally do we really need an Interviews link if there have not been any interviews yet? I'm not saying don't do the interviews, they were interesting when they last existed, but why keep a link up there? Isn't something like that quick and easy to remove / add? (I guess if it isn't then this is a null point) Btw, also, on the blog section, shouldn't we have a SFN logo or something? And make that link back to the forum (or at least home page)? Upon further inspection I now see there's a link at the very bottom of the blog, but some don't (e.g. ecoli's). Adding a SFN link at the top might be a bit prominent, but I'd be in favour of a quick link from blog to forums. Maybe we should also add a blog link in the links bar on the forum, instead of GUTs or Interviews? Just some thoughts! What do others think?
  11. The second part of the quote sounds in-line with what I know, but can you expand on the first bit? What physical effects become apparent? I read on the Wiki page that the value is calculated from the energy required to assemble a charge e of radius re, so I can see why it's very much a classical value. I also see it crops up in a Thomson scattering equation, and seems to work nicely there, but do you know of any other examples? Or anywhere it ties in with a theoretical model, as opposed to an equation? If it didn't (seemingly successfully) appear in that Thomson scattering equation I'd be tempted to call it a classical trick that isn't really useful in "everyday" life, would I be justified in saying that?
  12. I agree with you then, but can you explain this:http://scienceworld.wolfram.com/physics/ElectronRadius.html it never made any sense to me, and I still don't understand what it's really talking about, especially as I think your quote is totally correct.
  13. iNow: I don't see your reasoning. Rather than assuming point-like fundemental particles we have spherical particles, why then could they not be hollow? Mind you, a particle as a sphere is one thing, but a particle as a spherical shell is even worse! Klay: I don't really see your point. Are you saying that even if an electron were hollow then how could a virtual electron fit inside? But then if, and I don't think this is so, but if fundemental particles do have a non-zero size, then could they not be different sizes? Must an electron and a quark have the same radius? Ah, this is all a load of hyper-theoretical stuff anyway! Here's a better thought: a construction as small as we're talking about is so tiny that the number of virtual particles colliding with it must be tiny, thus making the Casimir effect correspondingly tiny (even more so than usual). So for example the "1atm at 10nm" value from my previous post is probably far too high for things on a molecular level.
  14. That's an interesting approach to the structure of an elementary particle. I've never considered that if an elementary particle is not point-like then it could be hollow. I suppose, to not-answer the question, it would depend on how strongly the particle wanted to stay together. Assuming that elementary particles are hollow spheres, and given that elementary particles do exist, we must conclude that the Casmir effect is not strong enough to make them collapse on themselves. Personally, along with the mainstream of science, I think that elementary particles are 0-dimensional points, but that doesn't stop your question being theoretically interesting, although I'm not sure we can gain anything from analysing it.
  15. 5614

    Square roots

    Does the Mathematica help file (or some other relevant documentation) not tell you? Also Mathematica will call on a square root function (from a standard library), whenver you type in sqrt (or whatever the command is), can you not view the code of the function and thus try to deduce what method it is using? Although it may be obvious from what I just said, I'm not familiar with Mathematica yet, but have used other similar software packages (Matlab, Maple etc.).
  16. I played the original one, it's quite simple and short, but it's very clever and is worth playing! I signed up to get an email when that new / better one is released! Thanks for the link.
  17. To gather enough energy to power a laser the area of the satellite would need to be quite big, however the International Space Station is also quite big and that has not had any major incidents. Mind, if something hit the edge of a space station it would have a different effect to if it slammed through a massive mirror! As for how to protect a satellite, I don't really know. A little bit of searching I did only gave me some articles regarding space debris / junk, but didn't talk about satellite protection. Part of the problem is that space debris moves as very high speeds, I can't really think of a way to protect something, only that you would have to construct it so that it could withstand a collision. One of the articles does talk about how improbably and very rare collisions are, but with a project like this you should probably plan for it! http://www.space.com/scienceastronomy/astronomy/leonids_satellites_991112.html http://news.nationalgeographic.com/news/2006/01/0119_060119_space_junk.html http://www.guardian.co.uk/science/2008/feb/24/spaceexplorationspacejunk?gusrc=rss&feed=science
  18. Hopefully you know that √(-1)=i Therefore: 1 + 1 = 1 + √1 = 1 + √(-1*-1) [as you know √(ab) = √a√b] = 1 + √(-1)√(-1) = 1 + i*i [as √(-1)=i, i²=-1] = 1 - 1 = 0 Thus 1+1=0. QED. Of course like always there's a flaw in it. Now I've shown off the one I know(!), here's a good link: http://en.wikipedia.org/wiki/Invalid_proof also Google searches will give you more, if you want.
  19. haha Transdecimal, that's pretty funny! Hmm, like Cap'n I'd try to increase the rate of natural selection through various methods (probably deemed as inhumane by those silly human rights people). If I was in a bad mood I'd probably act on the fact that parts of the world are soo doomed that they may as well either be isolated or removed. But in other respects I think educating the nation (people, on average, are far too stupid) and promoting technological advances through new scientific breakthroughs are definately the way forward!
  20. The laser anti-missile program that I had heard of, and has been succesfully tested, is this one (Tactical High Energy Laser): http://en.wikipedia.org/wiki/Nautilus_laser it has shot down many rockets, artillery shells and mortar rounds. Although apparently it has now been discontinued, not sure why, although there also are calls to renew it. At the bottom of that link (See Also section) there are some links to other similar laser systems. As for your suggestion: a satellite-based solar panel would be more effective than an Earth-based one in the sense that more light falls it on (the sunlight doesn't get filtered out by the atmosphere). However it is still a relatively slow method for collecting energy, to be useful it would really need to have very big solar panels (or mirrors), which would then be very vulnerable to space debris and solar winds etc. And then I think it is about 2/3 of light (the energy from the satellite) coming from the sun does not reach the Earth due to the atmosphere. I wouldn't deem it impossible, there is quite probably research going on along your lines right now, but there are several immediate problems that need to be addressed, as I outlined above.
  21. Hey! Welcome! I saw your other thread in Genetics, a good rule for forums is try not to create multiple threads . If there's something like this, where you want to introduce yourself to people on the whole (i.e. you do not want to post in one specific place) then the General Discussion forum is a good place to go. No harm in what you've done, you seem like a cool person, just thought I'd mention it for future.
  22. I'd agree with that. Every time a new syllabus has come out over the past 20 years there has been less and less hardcore content, especially in scientific areas. Most 1st year uni students can't follow old A Level textbooks... it is a bit sad really. A Levels should be significantly harder and fewer people should want/need to go to uni... but now we have reached the stage that we are at it would be very hard to turn around and go back the old ways, I think, regrettably.
  23. Correct, that is why I said it is what you are "seeming to suggest", rather than what you actually said. If they waited a year before teaching F=ma then what could they teach during that year? I think that being taught such a fundemental formula (even if just for general knowledge), alongside growing accostomed to what F=ma actually implies, in addition to everything you can teach that stems from it, I think being taught it early on is quite important. Also I don't know how it works for you, but in the UK the calculus that comes in later years is optional (it only gets taught to those doing maths or physics A Levels). If what you said went ahead, then only a limited number of the population would have ever heard of F=ma.
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