Royston

I've just finished playing Mass Effect 2, which I had to wait a month for, because the order was screwed up. It was good while it lasted, well written et.c but seemed to be over really quickly (I blame the structure of the missions / story for that.) I'm sure the game relies on replay value, you get extra perks when playing through again, but I see that as more of a chore than anything. I've also been playing the excruciatingly poor Avatar game, which I downloaded solely as a graphics test for SLI. It uses a modified engine from Far Cry 2 (I forget the name), and does look incredible on my set up...the game itself, is dire. I've also had a few games on Civilization IV recently, where I believe Civilization V is due out soon...so something to look forward to.

This is isn't homework, just something I decided to have a crack at, alongside my current course, and forgot about it. Just need confirmation on the last step. I wanted to find the connection coefficients of a hypersphere, so the line element is... [math]dl^2=R^2[d\psi^2+sin^2\psi(d\theta^2 + sin^2\theta d\phi^2)][/math] so... [math]dl^2=R^2d\psi^2+R^2sin^2\psi d\theta^2+R^2sin^2\psi sin^2\theta d\phi^2[/math] Where... [math]x^1=\psi[/math] [math]x^2=\theta[/math] [math]x^3=\phi[/math] So the metric is... [math]g_{ij} = \left[ \begin{array}{ccc} R^2 & 0 & 0 \\ 0 & R^2sin^2 (x^1) & 0 \\ 0 & 0 & R^2sin^2(x^1)sin^2(x^2) \end{array} \right][/math] Where the dual metric [math]g^{ij}[/math], is the inverse matrix of the above. Now this was the bit I was unsure about... [math]\frac{\partial g_{22}}{\partial x^1}=2R^2sin(x^1)cos(x^1)[/math] [math]\frac{\partial g_{33}}{\partial x^1}=2R^2sin(x^1)cos(x^1)sin^2(x^2)[/math] [math]\frac{\partial g_{33}}{\partial x^2}=2R^2sin^2(x^1)cos(x^2)sin(x^2)[/math] [math]\frac{\partial g_{ij}}{\partial x^k}=0[/math] for all other values of i,j,k. Now is it a general rule to partially differentiate each [math]x^k[/math] term, for increasing values of k (see the second to last equation for example). I'm guessing it is, because these will crop up in the connection coefficent equations, and determine which ones are independent, and non zero et.c...I just wanted to be doubly sure. BTW, it's coming up to 2am where I am, so I might be being a bit dumb here.

Which I respect, I was merely questioning the motivation of delaying sex, i.e encounters later on in life, will overshadow any teenage fumblings. Perhaps I should of emphasized 'side note' at the beginning of my post, as I was specifically speaking of this 'first time.' Don't get me wrong, I'm not saying anyone should rush in (there's no reason to), but... ...amongst a plethora of other misguided reasons why such a thing should be delayed. Well, it's highly unlikely anyone will feel comfortable doing something for the first time, especially if it's surrounded by some social stigma. Perhaps I'm being a typical 'bloke' about this subject, and as much as I recognise levels of intimacy, that doesn't mean I find certain hang ups, as a little daft. But as you said, it's personal preference.

There's nothing wrong with an alternative formalism, providing it makes predictions of physical phenomena, and improves on the original. IOW if it aint broke, don't fix it. Well a graph is mathematical. However, if you do plot a bunch of data, and find a trend or pattern, a mathematical model that predicts that behaviour would surely be more beneficial i.e I plug a value in, and get a result...but surely that's what you'd be striving for, once you've gathered your data. It might help, if you gave more solid examples.

As a side note, I've never really understood this attitude of why the 'first time', has to be special, or with someone you really care about and blah blah blah. The point is, it's your 'first time', so it's more than likely to be a confused, nervous affair, that will leave you wondering what all the fuss is about. It reminds me of statements such as 'your wedding day should be the happiest day of your life.' Really good days just happen, they're seldom something you can organise or arrange (within reason), the same goes for sex.

The ipad was covered on Newswipe recently... http://www.youtube.com/watch?v=QHGwI0v87Ec&feature=youtu.be&a

Ok, I just re-read your post, and you did say 'interest', not acting on those interests, but I made no mention that all paedophiles act on their urges. The discussion isn't about so-called thought crimes...so why bring it up. Ummm, I've just scanned through all the replies, and can't see any appeal to emotion. What does that have to do with paedophilia ? I agree there is a grey area at certain ages, and why such examples are dealt with, on a case by case basis. Yes, but within reason, see my last response. Yes, there are many examples, especially in the UK, of a pack mentallity concerning the issue, I don't disagree with that. Why ? Eh ?

Sure, it has nothing to do with manipulating a child to consent, how can you possibly compare the two. If somebody is incapable of restraining their urges, knowing that such urges will cause harm to somebody else, then it is a sickness. BTW women can be castrated, not that I think castration or death (as mentioned earlier) is a humane solution, by any stretch of the imagination. The problem resides in the brain, not the genitals.

No, there are plenty of examples of isolated stars that display the same behaviour without any influence from other bodies.

Not necessarily, events can be acausal, they just violate relativity i.e [math]\Delta{s}^2 > 0[/math] (see Minkowski diagrams), specifically the speed of light. Pre Big Bang models needn't be relativistic, they're not part of our Universe. Besides, as a similar example, even thermodynamics can be violated for a short time, as I'm sure you well know i.e there is leeway even with the most robust of physical laws. Surely you're making assertions about pre BB conditions ?

I think that's the problem with this question, modern geometry is a rather specialized field, and you're probably the best equipped to answer that question ajb. However, I've just started studying GR, so I'll give my opinion based on a basic understanding. AFAIK, the insight that has lead to modern geometry, would be Gauss' 'remarkable theorem', which did away with a coordinate system. Following that would be Riemannian geometry, where I guess a metric went beyond unit intervals (i.e the distance between each unit changes), so there's no such notion of distance...I know there's a lot more to it than that. My point being, geometry was a completely different thing up until the 19th century, and I'm sure, hitherto at your level, far more abstract now. I'm sure it would be a hard thing to define, unless you really knew the subject.

Yeah, I can't personally see such a thing amounting to much (albeit being impossible). It may convince some, that science is some antithesis to religion, or science had this agenda all along...but I'm sure that opinion is held already by certain groups / people. I certainly don't think it will cause any civil unrest, that we're not already experiencing.

I turned 33 a few months ago, and have two years of my degree (which I've been studying part time) to go. The way I'm tackling my education and career path, is studying towards a degree in physics, but with a concentration on astronomy i.e my final year (the next two years) will be courses solely on GR, astrophysics and astronomy, plus a course on EM (electromagnetism.) This way, I have a physics degree on paper, which is more flexible for work in the future, but also gives me the opportunity to apply for an MSc at Sussex in cosmology (my primary interest). I may even do an extra year on QM before this, as (perhaps suprising to some) QM is a heavy component in cosmology. Luckily for me, I found out recently a Phd student in physics at Sussex, has moved next door to my sister (see iNow's post) so needless to say I'll be visiting my sister more frequently in the future. I also have a friend who has been helping in geological research at the same Uni, so I'll be getting in contact with him in the new year...try and get some contacts, advice et.c As for maths, well I've got over the main hurdle degree wise i.e passed my higher applied maths exam this year, found out a few days ago, but I do need to practice more, as cosmology is maths intensive. With any path in science, it's a case of you get what you're given once you've finished your education, so keep your options open. You may find a career that's not scientifically focused, but demands those types of skills. Not sure if any of that is any use to you, but I was in a very similar situation to you a few years ago.

Both isn't it ? Assumption then reformulation. The interpretation is a consequence of the reformulation...or in other words, it's the only viable interpretation for a wave function not collapsing to an eigenstate. MWI is certainly attractive, at least I think it is, but is completely untestable, for all the reasons given. Personally, I'm more confused by the Universe harboring many worlds, where those worlds are orthogonal, yet the Universe encompasses everything within it...ugh.

Because it's not a general rule, you can only treat [math]\frac{dy}{dx}[/math], as a fraction in particular cases, I think mainly restricted to ODE's. I didn't think you could do it with partial differential equations, as ajb has shown, but I'm sure he knows better than I do.

It's most probably the card then, a 9800 should have no issues, your PSU is more than adequate, I run two 9 series through SLI on 450 watt with no problems. You've tried older drivers I take it ? Using the latest driver is always taken as gospel, but I had a lot of issues trying to get 190.62 to work...there was a conflict with my motherboard drivers. You shouldn't have much problem with Asus, I have the poor mans version Asrock, and my pc flies graphically. All I can think is your CPU or ram might be bottle necking, but my first impression is that you've bought a faulty gfx card, i.e 'it's never done high end 3D stuff' as you put it. A 9800, should be able to handle pretty much anything that's thrown at it, i.e you should be able to run any recent game with no issues at all.

I'm not sure what you mean by real and unreal. Real as in recording live instruments, or using samples of real instruments ? The only snag with samples is the nuances of the instrument are limited, where obviously you don't have that issue with a real instrument, such as a guitar. In any case, soft synths and the vast majority of hardware synths (bar analogue) are really just sample players, so there's not much of a distinction between real and unreal. I use Cubase, but I use outboard kit such as synths, mixer and guitar et.c Fruity Loops http://flstudio.image-line.com/ is another suggestion (you could pick up an older copy), very easy to use, but I'm not entirely clear what you're after.

So very true. Hungarian ? Albeit that was probably a joke, but within the field of science, yes, rather annoying that there's a stupid amount of money made from a lack of evidence, i.e science can't explain this prefabricated phenomena, lets test it, and waste a stupid amount of time wondering if it exists. Which personally I think is the salient point. Exhange of photons is ubiquitous (not particularly relevant), you can extract information from simple sysems, e.g a spectral fingerprint of hydrogen, now apply that to thought. You'd have to run an almost infinite number of experiments to correlate a spectral fingerprint to thought...it doesn't make sense. The distance radiation has from the brain, is quickly dissapated by ambient effects i.e it's micrometers, telepathy could possibly work if your head was next to somebody elses, and you had a way of decoding that information, but that is utterly impossible (see above). Plus, you can cheat the system, which renders it useless. More than happy to provide links.

It's a viral ad for Microsoft, I wonder if this will crop up on Mythbusters. I seem to remember they covered the Saatchi and Saatchi ad (surfing via dynamite in a river.) But yeah, it's fake.

You said it, besides, appeal to popularity is a logical fallacy. Source for these pics please.

Of course it has an origin, but when people (at least the people I've spoken to) think about the birth of the Universe, they think of an expanding dot within some black space (usually black). Nothing is a hard thing to wrap your brain around. This is still under much debate, i.e if the Universe is truly finite or infinite, I guess there's many ways of looking at it, once we get a general shape of the Universe, those questions will start to be whittled down. If you want some links, just ask.

What ? Like you said in your previous post that [math]a = b = 0[/math] and in the same sentence that [math]a \neq 0[/math] and [math] b \neq 0[/math]. So ? It can still be linearly independent if you defined x, despite the coefficents of a and b (providing they don't equal 0.) What's the difference between putting a coefficient on x and defining x, if you want it to be linearly independent ? However, I don't see the difference between 'all x', and 'any x' either. The problem is you didn't define x !

Right, but that's a rather odd way of putting it. The point is that the probability of getting a higher score decreases, due to the restriction of the scores, and specifically we're talking about phase cells i.e there is a restriction on position et.c. Therefore, within a given energy [math]E[/math], which is the restriction, the larger the number of molecules, the smaller the probability of a molecule occupying any given phase cell when [math]E[/math] increases. It's exponential, and as already said, it's only for gases in equilibrium, here's a simpler equation... [math]p = Ae^{-E/kt}[/math] [math]p[/math] being the probability, and [math]A[/math] being the normalization factor, the latter term RHS (the exponential) is the Boltzmann factor. Disorder, is really a rewording of the probability of knowing the position and the velocity of a given molecule, though I think that was already covered (sorry if I'm repeating what's already been said.) It gets more complicated when QM comes into play.

Annoyingly, life has been getting in the way, and I haven't been posting much recently, that aside... Most Helpful Member: iNow Most Knowledgeable Member: GDG Most Interesting Member: Kleinwolf (I'm utterly fascinated by his posts) Best Debater: JohnB Most Enjoyable Member: CaptainPanic Most Improved Member: GutZ

'Well hello Mr Fancy Pants', was my old signature.