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Or you could try something like this: http://www.scienceforums.net/showthread.php?t=23622

I read about one recently too. The article didn't say too much, but from the sounds of it strands of DNA were used instead of silicon. Whilst the biocomputer worked, it was slow and not very useful in a practical sense, although they do show potential. And that's about all I know. Google doesn't come up with much either. Hopefully someone else can expand on my answer.

Well I'm guessing not that fast seeing as the guy on MythBusters could only throw his at 25mph, whilst that probably isn't a world record I would estimate you throw somewhere in that region. So I guess what we'd like to know is why it is cutting so deep into the plasterboard. Well the mechanical version on MythBusters threw the card at 155mph, this is a lot faster than you have any chance of throwing your card, however it only caused a small cut when the card was aimed at a human. So we have: 155mph --> small cut on human ~25mph --> 5mm cut on plasterboard I reckon the explanation of your 5mm cuts is more to do with the material (ie. plasterboard vs skin) and not that you can throw the card significantly quicker than 25mph. I'm in the UK, but I know it isn't that hard to make a dent in the average internal house wall, just from occasionally throwing things, or hitting the wall whilst carrying a heavy object. Two things to conclude with: firstly I can't really replicate this experiment at home due to technical difficulties (the air keeps stopping my card from reaching the wall at a decent speed!) and secondly 5mm is actually quite a deep scratch just from a card, is that an accurate value? And is this from just a standard playing card? And so is the cut about 0.5mm wide (roughly the width of a standard playing card)?

I think that's recent years of your life, not in general. Grignard reagents (general formula: R-Mg-X where X is a halogen) have been around for about 100 years now. I found a little organometallic timeline here:http://en.wikipedia.org/wiki/Organometallic_chemistry#Organometallic_chemistry_timeline ... so whilst there is currently a lot of work going into the field, it does have quite a bit of history behind it also. Having other metals in organic compounds seems, I suppose, quite normal to me. Something like CH3-COONa for example, is a compound which just seems 'normal' to me, despite the alkali metal in it. Obviously you could argue that it's CH3COO- Na+, but the idea of a metal within an organic compound doesn't seem that strange to me. Sticking in a transition metal makes you think again, just because it's a transition metal, but at the end of the day just like Cl, Na, Li or Mg can attach to the end of an organic compound, so can a transition metal. I suppose I would define an organic compound as a compound containing carbon; except for CO2, CO & carbonates (and probably some others I haven't thought of).

Right. Are you sure that's correct? You're saying that between close plates (as used in the casimir effect) the vacuum is 'more complete' due to the reduced number of virtual particles (fact), so the permitivity is less and therefore light travels faster (does it)? Using [math]c = \frac{1}{\sqrt{\varepsilon_0 \mu_0}}[/math] formula you would seem to be correct. That is; between two close plates, where there are noticeably (casimir effct) less virtual particles, [math]\mu_0[/math] would decrease (or so it seems, to me, at the moment) and therefore c increases. Well now you've got me interested! *Investigating* OK, so the Scharnhorst effect is what you're talking about. The Scharnhorst effect is the predicted effect that a photon moving between two close plates will travel faster than c. Scharnhorst was able to some mathematical analysis of this using QED (quantum electrodynamics), I haven't found his work yet though. In 2002 a 25 page paper, which can be found here: http://arxiv.org/PS_cache/gr-qc/pdf/0107/0107091.pdf shows that the Scharnhorst effect does not "automatically lead to causality violations" (quote from the abstract of the paper). I haven't read that paper yet, although I hope to soon. Maybe I'll be able to answer your question when I have.

crypt32chain.dll is a file which is part of a trojan. crypt32.dll is a Windows file and is fine. Therefore you are ok.

No. An image in a form will not affect the commands and formulae within it. Well, you could argue that displaying the image will require processing power and will therefore make it run slower, but you would not normally notice that.

It also depends on the angle between your eyes and the monitor. If I move down, so the monitor is pointing above my head then it seems all black. The higher above the monitor I go, the lighter it all becomes. And whether I slouch or not does make a bit of a difference. But normally I'd see grey stripes on blue background.

Indeed, they work using the same principle. Although your average non-newtonian fluid would be penetrated by the huge force exerted by the tip of a bullet, the fluid used in those bullet proof vests becomes a lot harder and a lot quicker than the kind of fluid you can make at home.

I've been very busy recently, although when I do pop in I do think it is less active than it used to be, back in the good ol' days! I'm not sure why this is. I'm busy, that's me covered, but I come back and it's relatively quiet here, which is sad. I don't know why this is. Does vB do a daily post count we can access? If so was it really 38? Or as blike suggested, a lot more?

When viewing the form click the View button near the top-left of Access. As shown here: http://img.photobucket.com/albums/v601/5614/access.png Select the Design View and you can do a lot from there. As doG suggested; create your image in Photoshop, save it as an image and then go into your Design View and import the image.

Reinstalling WinXP should fix the problem. You can reinstal Windows without formatting by botting from the WinXP CD. Chose Instal from the CD. Then when it finds your current version of Windows select Repair. Do it in that order, do not select Repair on the first screen. By "turns into the old one" do you mean it goes back to default? Or what it should be? NB: If you reinstal WinXP you will need to re-download all Windows updates and you will lose your Theme (default desktop background, screensaver etc.), but that is all. All programs will still work.

Happy Birthday!

I'm not going to because of the money, and besides, I'd prefer to spend money on upgrading my computer. However I think the PS3 is the best console out there and I wish it the best of luck with its blu-ray disk and I can't wait until The Cell (the processor inside the PS3) is reverse engineered for PCs.

I agree. In the end the reasons will be "because you're human", "because you want to" or "because that's how the universe is". Whilst you could define that as a reason, it is hardly a deep explanation as to why we are doing it. Maybe talking about the neuron paths in ours brains which cause us to do the things we do. I agree with this too. Whether it is basic instinct, our desire or malfunctions within our brains, there is an explanation for all human actions. But that does not mean that everything is done for a reason. So I've been thinking through a few examples and each one seemed to have some kind of reason, but in the end I come back to the true randomness of nature. And I ask you this: why does one atom decay in a radioactive material and another atom not? What is the reason for this atom decaying and the other one not decaying? My initial thought was that the reason for this is so that the radioactive compound becomes a more stable, however then I realised that this was not my question. I am questioning the reason behind the randomness of which actual atom decays. As that is, what I would refer to as, true randomness, I say there is no real reason as to why one specific atom decays whilst another specific atom does not (in a radioactive material). Whilst initially I agree with Cap'n saying this is pointless, I'm now challenging you instead!

Indeed, that is a much better question. Whilst he is popular due to his disability and popular books, I personally respect him for his work on Hawking radiation.

Motherboards (mobo) will have a specification. For example a DDR compatable mobo might not work with DDR2. Also most mobos have a limit to how much RAM they can take. I believe mine is 4GB, not that I'd ever get that much, but it's still a limit. So there are compatability issues. Some mobos will be really fussy and will only accept certain, generally non-standard, components. As these are non-standard this could be why specific model numbers are given. That is you have to use a listen model, nothing else works. Alternatively it could just be the manufacture recommending the most common components used, to make it easier for you, or it could be they're in some sort of business deal and must recommend a specific brand component, even though others would work.

I have to say that whilst I still have that annoying motor sound in my head, that was a very impressive video. The way in which its legs adjust to being kicked and over rough terrain etc. are very clever. Whilst I can't say that I'm up to date on the latest advances in robotics, that video shows quite how advanced our robotics have become, and certainly shows a lot of potential for the future.

I think what the others are all getting it is the key to this; mp3 files do not seperately store a vocal layer and instrumental layer, which you could seperate. Therefore you really have two options. One is to try and find an instrument only version of the song, and the alternative is to try and filter out the vocals. Like Ndi suggested, filtering out the right audio frequencies should remove the vocals, although generally this will be quite crude and nowhere near perfect. Although it could be good enough for your karaoke CD. I think it can also come down to how long you are willing to spend. When I'm image editing I can do a quick and cheap job, or I can zoom in to 8x and edit each individual pixel one by one. Obviously editing pixel-by-pixel is very time consuming, however if I do it well the image will turn out perfectly. If you spend a long time manually filtering out all the audio it probably will turn out very well, however it would probably turn out to be too much work for what it's worth.

Well, I've just applied for physics at various universities. Originally I thought I'd then go into research, actually originally I thought I'd study computer science, but once I decided on physics it was research. Then came the idea of lecturing. I don't think I like the idea of teaching at secondary school (high school), although teaching at a higher level sounded good. Then I realised that I could teach at a higher level (uni lecturing) and do research between lectures! So I suppose that's the current dream. Obtaining a physics degree generally means you're good at maths, so all sorts of jobs in banks etc. become available. Teaching, research, finance, military, government, space industry, computer companies like IBM and Intel will employ physicists, building design (will the building collapse under its own weight? Where would the stress points be during an earthquake?) and motoring industry (designing engine, aerodynamics etc.), just to name a few. And of course it takes someone to think like a physicist to develop the idea of blu-ray disks, what with using a blue laser as it has a shorted wavelength etc. And this brings more ideas to mind, designing hardware like lasers and particle accelerators, medical physics like MRI and radiotherapy, material physics like developing stronger and lighter material. And so on and so forth.

Subway is healthy? I mean, I suppose it's not McD, but still! I'm generally quite boring with food. For example I would live off plain pasta, maybe with a simple bit of cheese or mushroom source, but you get the idea. So when it comes to sandwhiches, for me, it's gotta be warm white bread with egg mayo (or tuna and sweetcorn). Although it's gotta be good egg (or tuna), not some cheap and horrible imitation of the real thing!

Haha, very good! Waste of a post, but I had to say it! And this is General Discussion after all!

Can you expand on that please. AFAIK there's the brute force method. Also as the months go by there will be more Rainbow tables (tables of precalculated passwords and corresponding md5 hashes) that can be used to quickly crack md5 encrypted passwords. Now if we combine this with the increasing efficiency of brute force attacks, and the overall increase of computing power available to the average user, it has certainly become quicker to brute force md5. Is this what you mean by "quite a few developments in cracking it recently"? Or is there something else I'm not aware of?

Einstein's EPR paradox, I could say a lot on the subject! Einstein is wrong, to the best of our knowledge. Einstein did not like quantum mechanics and specifically did not like the Copenhagen Interpretation. Einstein presented what he thought were faults with QM to Bohr, however Bohr always managed to show that Einstein was wrong, and that QM was correct. These Bohr-Einstein debates (on whether QM is correct or not) are well documented, you can see a summary here: http://en.wikipedia.org/wiki/Bohr-Einstein_debates Einstein's final argument against QM was that of the EPR paradox. Sadly Einstein was not alive when the solution to this apparent paradox was discovered. In 1964 Bell came up with a thought experiment which, if carried out experimentally, would reveal whether Einstein and the EPR paradox were true, and QM was false, or the other way around. Although originally Bell never planned for his thought experiment (often referred to as Bell's Inequality) to be carried out experimentally. However in 1972 the first experimental results were being released, most showed that Bell's Inequality was violated, meaning that Einstein was wrong, QM is correct. I'll just interrupt at this point to say that Bell set up his inequality assuming that Einstein was correct. Hence if Bell's Inequality holds true then Einstein is correct, however if it is violated then QM is correct. However it wasn't until 1982 when the experiment was carried out by Aspect that physicists were fully convinced that QM was correct. Even to this day there are more tests, and they all violate Bell's Inequality. About 6 months ago (before I knew about the EPR paradox) I was thinking about physics and stumbled across what must have been Einstein's thought pattern when he came up with the EPR paradox. I came on here (SFN) and asked how, when we know QM is correct, could my "paradox" (the EPR paradox) be explained. A few people recognised my question as the EPR paradox re-worded, and started talking about EPR and Bell, I had to take a step back for I realised that I'd reinvented, as it were, the EPR paradox. First I read more regarding the EPR paradox, and thought that Einstein was right (even though I knew QM was right, I couldn't see a solution). Then I read about Bell's Inequality. A great thought experiment, I thought, that couldn't be carried out. But then finally I read about Aspect's experiment, which shows once and for all that the EPR paradox is not a paradox, that Einstein was wrong and that QM is correct. I guess it's taken me all of that to say that I do think QM is the correct explanation of the world, and therefore accept the consequences of this. Yes I do think the universe is based on probabilities, yes I do think that "God plays dice"*. *Just for those who don't know that quote, it's something Einstein said, he actually said he didn't believe that Einstein played dice with the universe, what he was saying is that he didn't accept the probabilistic nature of QM.

swansont: I like the standing wave and nodes explanation, thanks. Severian: I've seen programs like that before and I was searching for one before I posted, but couldn't find it so gave up and used Paint, thanks for that though, it'll definately help in the future. Nice to see you understand now, and I'm not entirely sure what your timeline confusion was, but some Feynman diagrams do have a time axis. So if you go back and look at my first diagram there are no direction arrows, the diagram has no reference to time. Whereas my 2nd and 3rd diagrams have arrows which represent the flow of time. In those diagrams the x-axis represents time. All the particles have an arrow representing which way in time they flow. Photons do not need an arrow, as time, in a photon's frame, is meaningless, as they travel at c. Furthermore in my diagram I've shown a positron as an arrow moving forward in time and labelled as e+. However Feynman showed, mathematically, that a positron moving forward in time is identical to an electron moving backwards in time. So instead of representing the positron as I did, I could have drawn the arrow pointing to the left (backwards), and labelled it e-. Now I've got a question regarding time in Feynman diagrams. Some show time on the x-axis, some on the y-axis and some have no reference to time, so what is the correct way of drawing a Feynman diagram?