Radical Edward

we'll have to wait around for a while then....

I think he means you should be able to see the galaxies whizzing away at velocities >c this would play havoc with red shift. I can't say really, I'm not sure, as I was never so big on cosmology.

not having done the maths, I'm not entirely certain. what I can say is that no energy should be lost, and I strongly suspect that the answer lies in momentum conservation, and of course the pervasive Lorentz Transforms. you might want to work through those and see if you can answer it for yourself, they aren't too complicated. I'll do it as well to see if I'm right or not ^^

oxygen is pretty reactive stuff yes... but water.. not so. either that or there is a hell of alot of life on europa, in the carbonaceous chondrites, under the surface of mars, drifting around the galaxy generally.....

I know the paths won't be shorter, if anything they will be alot longer, though I haven't seen the proper research, so I couldn't comment on the amount of gravity acting on you and so on. whatever I think it will just be a method of getting from a to b using the gravity of all the planets and so on, rather than making the effort yourself... and yes, I know if you warp space time the straight line isn't always the shortest route, though I try to stay away from objects with large masses like that since they're often rather hot or dangerous, and I don't want to wreck the paintwork on my spaceship.

I did comment on one of the threads, but I figure I may as well here too. <conjecture> this looks to me like nothing more complicated than just being able to accurately model and predict the direction of the pull of gravity and it's time evolution over a large volume. It would be useful for low energy transport and perhaps bizarre looking, but stable orbits (at the very least, semi-stable since they might require a little tqeaking from time to time) I suspect that while low energy, these paths would be very slow. </conjecture>

I just noticed that article on the gravitational highways. it just looks to me like they have developed a method of figuring out all the paths of low energy change to get between places, nothing really more complicated than that (similar to that method of getting to the moon). I will ask some people in the department next week if you like, unless someone beats me to it and provides a more comprehensive answer. I would expect that these paths are rather slow though, nothing gets you places quicker than a straight line - though you might have to expend rather alot of energy and tread on the neighbour's lawn while doing so.

Do I know you Zarkov... that name seems rather familiar.

when I talk about life in a computer, I really mean something that emulates the functions of life - namely reproduction, metabolism and so on, within an environment that has been created for it (the environment being created for it). There have been several programs that do this, probably thousands. one example would be the computer game 'creatures' if any of you have come across it. this is entirely different to sentient - which is what programs like that alice are trying to work towards (although that one is more of a conversation thing, I doubt it has any feedback or learning mechanism) It will be interesting if and when computer sentience is achieved, to see if it meets the criteria for being 'alive', in the real (worldly, rather than within the computer) sense of the word - I doubt it will rather strangely, as there will be no real funtion to maintain homeostasis, reproduction and other such things. maybe the definition of alive will need looking at again, or perhaps we will have to accept sentience that is not alive. who knows.

I mean proper physics, heh. Quantum mechanics and stuff like that. Astrophysics and perhaps more Cosmology are okay I guess, but they're a bit funny in that they are science the wrong way round - looking at things and trying to make up any old thing that fits your observations. Alot of it seems rather ad hoc to me, when considering things like Dark Matter. QM on the other hand can actually be tested, and theories generated that show some pretty wierd stuff that you can actually look at. that money sounds nice, but I've never really been interested in money. provided I have three meals a day and a roof over my head I don't mind too much

23 year old Physics MSci Graduate from the UK here (Imperial College London if any of you have heard of it). Currently studying for an MSc in Optics and Photonics, with an interest mainly in Organic LED/Solar Cell/Electronic technology

provided you don't go onto a lake in the middle of a lightning storm, with a copper ring in your nose, while shouting 'All Gods are Bastards' you should be okay. seriously though I wouldn't worry too much. that incident you mentioned sounds pretty freaky, and if the lightning hit your house, I'm sure it would find a better route to the earth than through you. though it might be a good idea to turn off any electrical appliances in the case of a storm directly overhead.

I was discussing this with some colleagues in the pub last night (the pub and the coffee room are the places where all big thoughts occur, not the lab - this is a common misconception!) Quite an interesting discussion really, and it brought back the baloon analogy, which explains it fairly well. imagine space-time as the surface of this balloon, say it's a spherical balloon. there is no center, no origin of which to speak, and when we talk about the universe expanding, then the surface area of this balloon is getting bigger, in that all points on the balloon get further away from all the other points, while not moving away from any specified point. In short, the old school church was actually right, we are at the centre of the universe. but then so is everything else. we still couldn't figure out what red/blue shifting of the CMB would give you motion relative to, other than that particular point in space at the time the universe left thermal equilibrium. Still it sounds alot like absolute motion to me.. :/

I doubt it. light would be more useful when considering it as an energy source, and location of food, such as algae and such things. Thermal detection (and hence thermokineses) can be achieved in other ways.

gravitational matrices? even a search on google didn't help.... well satellites regularly use the gravity of various planets to slingsho them into new orbits, and then say when we fire rockets at the moon, we don't aim at it, but at the patch of space where the earth and moon's gravity nullify one another, and then just fall the rest of the way. when interstellar (dunno about intergalactic... that might take a while) travel is realised, these things will have to be taken into account.

neurosurgery is just cutting out the right lumps of meat. I suggest trying to find out the function of general anaesthetics, or perhaps something more worthwhile, like what consciousness is. alternatively do physics....

it's a convenient label. I'll let fafalone explain it tomorrow as I can't be arsed right now. sorry

there is a difference between seeing 'stuff' in the distance, and the universe itself, since the universe includes space-time, not merely matter and electromagnetic radiation (aka light/radio/gamma waves) you could never travel away from space-time to such an extent as to see it as a ball in the distance, since in order to do so, you would need to be in space-time (and be within the light cone of any existing matter)

indeed, but what about my counter example. tonight my friends and I were trying to work out what the red/blue shift of the CMB would be actually relative to, and we couldn't figure it out. oh well......

thanks. I need to get myself out of the 'if it's not physics, it's not worth it' attitude.

do you know of any good books?

oops, unregistered is me by the way.. I forgot to log in.

oops, unregistered is me by the way.. I forgot to log in.

the bottom seven points are a pretty good definition of life: http://www.geog.ouc.bc.ca/physgeog/contents/9a.html although rather interestingly virii don't fall into all of those caregories. furthermore, if you are to take the quantities in their more abstract form (namely metabolism, materials and biomass) one could argue that certain computer programs are alive, if they are programmed with the correct features, albeit in an extremely simple way.

not to mention the blocked light would have to be put back along it's original path so you don't get a shadow....