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Well, err, maybe!? It kind of depends on the original article (I'll try and look for it tomorrow, as I have access to the NS website, but it's late now). If the infinite number of multiverses are supposed to contain every variation on the laws of physics, then perhaps his argument is correct. However if each of the multiverses starts from some ground physical laws, then as each of the multiverses start from some common basis, which must by their existence include the multiverse 'law'(?), each successive multiverse is allowed and allowed to split again ad infinitium. For example, one multiverse theory is that a universe splits in to two every time a decision is made (where a decision can be something like a photon coming out of a superposition and chosing a definite state), if the universe merely splits based on a decision, whilst the two will be very different, the fundemental laws will remain the same, and thus you would not get this paradox. [edit - stupid auto double-post merger thing, below is a seperate 2nd post] The orignal article was, suprisingly, little to do with multiverses. The author of it, Michael Hanlon, is the science editor of the London Daily Mail. In the article he talks about all the big and crazy physics stories that we hear today. That the LHC could create a black hole that would consume the Earth, cosmic strings, crashing branes, "titanic slabs of maths that give rise to the big bang in the exotically lovely ekpyrotic universe of Neil Turok." He also gives the example of: He says: "Fun yes, but is it harmless?". He says that physicists will nicely dismiss ghost theories and UFO sightings. "Show us the data, we say to these deluded souls." But he then turns around, saying: "The danger is that on the wilder shores of physics these standards are often not met either" (referring to the wild theories previously mentioned). The comments page for the article, where the OP's quote can be found, is here: http://www.newscientist.com/article/mg19726460.200-physics-porn.html

I don't know specifically about these K2 High-Intensity LED's, but the high-intensity LEDs I've played with are, well, the name gives the game away! They're just normal LEDs, but they're a lot more powerful. Take one like I have and shine it at a wall 1m away and you will see a ~10cm diameter patch of light, they're not lasers, so they spread out a lot. They'd light up a small room in the dark, and you wouldn't want to look straight at it, although it wouldn't harm your eyes if you did (at the least the ones I have). I see no reason why this would create a red around a white core halo effect though. At best your translucent tube will be one colour, although this will be a challenge because it will be very bright around the LEDs, but get rapidly less bright as move up the tube away from a LED.

Ah yes, true, they're mathematically identical, and each method is equally valid. Interesting!

I can understand why you're confused, and I'm not doing an amazing job of explaining, but I'll keep trying: In a cartesian (or Euclidian) system the light will look like it bends. Look like it does, nothing more. This is because using a cartesian system for space-time is a bad model, because space-time is very much non-Euclidian. In the correct or real-world non-Euclidian system, light does only travel in straight lines (where "straight" is defined within the non-Euclidian system). Light has the appearance of bending in a Euclidian system, but only because the Euclidian system doesn't represent the bare truth, as it were. In the real-world the system itself is bent by gravity (hence it is non-Euclidian) and light follows this curvature, but remember that this curvature only exists if you're using a Euclidian system, in the real non-Euclidian system you don't have a bend, as it were, because the bend defines the system, the bend is the shortest distance between two points. The human brain thinks in terms of Euclidian systems, we can't really mentally process a non-Euclidian system, I think it is this that you are struggling with.

Gravity has an infinite range, I think this is what you mean, but I don't like your wording . Err, wrong way around . Light can accelerate as long as it is the direction (and not the speed). FYI light could orbit an object, if the object were big enough and light started off in the right direction. And whilst a gravitational field does strech to infinity, it is possible to "escape" it. If you have more kinetic energy than the graviational energy it would take to move from the planet to infinity, then you would "escape" the field. This velocity is known as the escape velocity.

Yes. In the photon's referrence frame, now you're just trying to make it complicated ! It's a hard one, as you say the photon does not experience time, so maybe we could argue that the photon does know what its polarisation is, because after the detection, and before the detection, it's all the same to a photon. Big maybe! Regardless of what the photon may think, in our frame, the photon is in a superposition. The detector collapses this superposition and forces the photon to chose a state. When a photon in a superposition is observed, and the superposition collapses into a definitive state, is that a truly random? If you have an entangled photon, which is either polarised up or down, when you observe it, is it truly 50/50 whether it is up or down? It could happen, however I don't think we could ever claim it did happen, due to the uncertainity principle. More to the point, as said before, the superposition collapse is instant, so is there really any problem? This is kinda random, but you may find this: http://math.ucr.edu/home/baez/physics/Quantum/bells_inequality.html which talks about the EPR paradox and Bell's Inequality interesting. It's a long read, take it slowly!

Just to add a picture to Swansont's post: a plane will take the shortest distance between two points, because it wants to save fuel (so it's cheaper). To do this it will follow one of the lines shown in the above image. However this "line" is actually a curve, and you might think that therefore this is not the shortest distance, but that is because we're modelling the spherical and 3D Earth on to a 2D surface. In the real world it is the shortest path, but when you project that on to a different set of axes the transformation distorts it (basically we're projecting the real world, a 3D non-Euclidian system, on to a 2D Euclidian one, so this projection cannot be interpreted literally, not without first undoing (or taking in to account) the effects that the transformation has). Is it any clearer now?

If you short circuit a capacitor (attach a single, short wire across the terminals) then it will discharge very very quickly, because the wire has a low resistance, and so there's a big current going through it. Remember a capacitor stores charge, and current is the flow of charge, so if you have a big current then there's lots of charge leaving the capacitor per second. However you can slow this down by putting more resistance. If you attach a resistor and LED to a small/average sized capacitor then it can keep the LED lit up for 10 or 20 seconds. I have a special "supercapacitor" in front of me that is 20F (a massive capacitance) and this could power a mini robot for several minutes, and can keep an LED lit for many minutes (I've never tested how long, but if Q=CV, I charge it up with 2.5V, so Q=50C. Then Q=It, a 100ohm resistor/LED at 2.5V will draw 2.5/100 amps, giving a time of 2000seconds, or over 30mins, wow, that's more than I expected!) Just for interest: sometimes you do want a quick discharge though. If you need a very high current, higher than you get from the mains or a generator, then an easy way to do this is store lots of charge (energy) in a capacitor, and then discharge it all at once, giving you one mega big current!

Remember that in the rubber sheet analogy a dent is where another object will fall into (or curve around, depending on speeds and masses etc.), this is because in the rubber sheet analogy there is some gravitiation source beneath the sheet, so whenever there is a dent things will fall in to it. In real life there isn't this gravity source "beneath" the real thing, instead the curvature itself represents a force. The rubber sheet analogy is good for getting a picture, but the method via which it works is different from real life. Rubber sheet has a gravity source beneath it, so when there's a dent things fall in to it. Whereas in real life the dent, which is in space-time, which isn't as such a physical thing (you can't pick it up), represents a force. We are talking about this picture: In this picture, if you wish to stick with the rubber sheet analogy, the rubber sheet would be beneath the Earth and the sun, and there would be a dent at each mass. The dented zone is where the blue field around the sun is, or at least that is where the field is strongest, in theory gravity doesn't become 0 until you are an infinite distance from the source, but it does get quite weak quite quickly (it loses strength at 1/distance²). Initially the light (the white line) is angled such that it will go past the sun. This is not the light being pushed away, it is merely the initial direction of the light. Light going straight in to the sun will go straight in to the sun. Light going off at 90 degrees to the sun will never be seen by us. But light that is angled to brush past the sun (as the white line initially is) will be seen due to gravitational lensing. If the sun weren't there then the white line would be straight, at the angle it is at the beginning of the arrow, so it would go past the Earth. So the white line is initially going to brush past the sun (if it continued in a straight line). However after a short while it hits the blue zone around the sun, the sun's dent in space-time, where the light feels a force due to the sun's gravitational field. This causes the light to curve around the sun, just like a ball bearing would around a dent in a rubber sheet, and just like commets and asteroids do when passing by the sun. The light then "escapes" the sun's field (or at least the really strong part, which is the blue bit), and proceeds to travel in a straight line towards the Earth. When we see this white arrow arriving, it would look as if the white arrows came from where the orange arrows came, because our eyes can't account for how the photon has been curved by gravity. I hope this explains the picture, and in turn helps answer the original question.

Klaynos has replied to most of your post, however I will add my own expansion on his response: In the analogy the light would fall down in to the dent, because the analogy says that wherever there is a dent things will fall down in to it, as if there were some gravitational source beneath the rubber sheet. In reality there is no gravity source beneath space-time(!), the dent itself is the cause of the force. A photon has energy and is thus affected by this force. An alternative (and equally valid) explanation is that the photon must follow the shortest path, and the shortest path in a non-Euclidian system follows the "contours of curvature" in that system, i.e. a photon will follow a bent path, if space-time is bent. I think the definition of "straight" may be what is confusing you. See the end of my previous paragraph. Light that is going directly towards the sun will get absorbed by it, of course, but light that is going to pass nearby to the sun will be affected (it's path bent) by the sun's gravitational field. This is known as Gravitational lensing, follow the link and look at the images, which show what is happening.

This is an interesting thread. Here's another thought: Am I correct in saying that the acceleration of the universe is accelerating? (I think this is true, but I'm unsure) As in: [math]\tfrac{da}{dt} \neq 0[/math], where a = acceleration of the universe. If so that would imply, by your model, a varying gravitational field strength, which has not been observed. This could be explained if the value of da/dt is very small, maybe over the last few hundred years the change has been too small for us to observe. There must be numerical data about the acceleration of the universe, and how much that acceleration is varying by, if it even is.

This is an American system, so I have no idea, but if no one here can answer you then I'm sure you can find it out on a med school website. If not then get a contact email address at where you're thinking of studying and send them an email asking which they prefer, they're all friendly people!

Here's an image that I found that may help you: The dotted line would be the path of a body, passing by the another bigger body, it curvature due to gravity. IMHO the curve is a bit exagerated, but it gives the general picture. As for why exactly the light follows the bend, well in this picture: imagine if you took a little ball bearing and rolled it along, so it passed close to the dent in the sheet. The ball would roll along, then would bend as it went near the indented part, then, assuming it's moving fast enough and the pull is not strong enough, it will escape on the other side and continue in a straight line, but at a different angle to the original path, because the indentation in the sheet caused it to curve. The exact same things happen to a photon passing by any other object with mass, although it is only really noticable when the other mass is really big, like a planet or star. Although it's also important to note that this is more due to the fact that the photon must follow a "straight" (shortest distance between two points) path, and not because it falls into where space-time (the sheet) is bent.

Aye, my bad, my "then what" question I posed I should never have said, because there is no "then what". Having points moving away from each other at a relative speed >c is allowed, as no information is transferred. The only "then what" is that then these systems will never be able to communicate again. As for taking the rubber sheet analogy, setting the rubber sheet to accelerate (expand if it is a balloon shape), and then claim that this is the cause of gravity (the objects on the surface would cause a dent due to their inertia), and then relay that analogy back to the real world... hmm, it's interesting. I can't (at the moment!) see any major flaw... As we can't tell the difference between being in a gravitational field and being in an accelerating frame, then doesn't that mean that your model is mathematically identical to any gravitational field model? If so then it would make it a good analogy, but would it be possible to tell which is correct? Might we end up at relativity's "both views are equally correct"?

What!? You asked a right/wrong style question, which I then told you was wrong, and I then proceeded to explain why using well known and accepted physics. I don't see what your problem is and clearly you cba to explain your problem, so how can you ever expect to resolve it? From your apparent attitude the only thing I can assume you mean by "open minds" is people who will just nod blindly at you and tell you that everything you says is right, even when it's clearly a load of bull. Au reviour and good riddance to you.

Yeah something like that! Although remember that the 64kg of uranium -> 0.6kg of pure energy is what was generated by the first nuclear bomb. I'm almost certain though that more efficient designs have been developed since then, allowing you to drop a smaller bomb but obtain the same (maybe greater) yield. Also remember you can use other materials, namely plutonium. So you're on the right tracks, but it's a bit more complex than it seems, at least initially, as always!

Inertial and gravitational mass are the same thing, this is the Equivalence principle. Kygron: you're setup seems interesting, but I have a few comments about it (these are just initial thoughts): Firstly do you have to turn the rubber in to a balloon shape? Can't you just keep it flat? Either way you still need a gravitiational source pulling the balls down, although this is one of the flaws in the analogy. You're trying to fix a flawed analogy, why not just accept it is wrong? [edit] after trying to argue that you don't need a mass in the centre I've convinced myself you do need a mass in the centre, at least if it's not expanding. As for then claiming your balloon must expand, if it were expanding forever then in the end it will accelerate until points on the surface are moving at the speed of light with respect to each other, then what? The balls on the surface would be moving away from each other at >c.

I don't understand your question, there are many different wave shapes... Generally waves observed in physics will follow some sort of a sinusoidal shape. When you talk about a photon it is comprised of two oscillating waves (one electric, one magnetic) that are both sinusoidally shaped. What exactly are you asking? (try to be specific!)

It's a bit too theoretical though! And yes (I just double checked) Little Boy (the nuke that was dropped on Hiroshima) contained 64kg of uranium, 0.7kg underwent fission, and 0.6kg became energy.

Imagine this situation: Frame 1: stationary Frame 2: moving at speed u w.r.t F1 (frame 1) A particle is moving at v in F1 v' = velocity of particle in F2 = v - u Differentiating: a' = acc of particle in F2 = dv/dt - du/dt dv/dt = a = acc of particle in F1 du/dt = acc of F2 w.r.t F1 If F2 is inertial then du/dt=0, and in this case: F1 gives: F=ma F2 gives: F'=ma' If F2 is non-inertial then du/dt=aframe F1 still gives: F = ma But F2 gives: F' = ma' - maf and so Newton's Laws are not valid in F2, when F2 is non-inertial (i.e. is accelerating). To "fix" this we add a pseudo-force. Let this force be: Fp=-maf So F'tot=F'+Fp And therefore: F'tot=ma' To use Newton's 2nd Law in non-inertial frames you need to include an extra pseudo-force. I can give a nice little example if you would like?

The missions might have inherent restrictions, but there's many ways of solving them, and I find the fun is in finding and implementing a solution. I enjoy being given a problem and having to solve it, and from that get the "I did that" feeling. Whereas you seem to prefer being given an open environment and setting your own challenges. I'll give Phun a proper go in the next few days, but I'm fairly certain I'll 'stick to my guns' and not change my view, which of course is purely opinion based! Moving on to more important matters - I somehow doubt I can find the full version of Armadillo Run on BitTorrent!

Oh no! Another one of these things that I now have to spend my time playing with!! Although with Phun seemingly there are no missions etc., just an open space environment. You're limited by your own creativity, but at the same time there's no sense of completion that you get from solving a level in Armadillo Run or the Crayola Physics games.

Eh!? You're saying that taking a person's mass, converting it to energy, "beaming" it somewhere else, then reassembling it might be a way towards teleportation!? Are you crazy!?!? Have you ever seen pictures of a nuclear bomb? Hiroshima was an example of 0.6kg to energy, humans weigh 60kg+, to give you an idea of the scale involved. Yeah in theory, but 1) you could never reconstruct the matter, at least never if you want to reconstruct a living being 2) it's just crazy I tell you!!

After seeing IA's post before mine, I Googled x-ray lasers a little and it seems they do exist. They don't work in the same way as a normal laser (from what I've read), and I think this is because, as I reasoned in the quote above, the energies involved would be too high. But you can seemingly produce x-rays which have laser-like properties. For example: http://en.wikipedia.org/wiki/Free_electron_laser [edit] doh Cap'n! You and your 1min head start!

Aye, true, calculus should be taught earlier, then it could be in-line with classical physics. But alas, I fear it will never happen, though it should. That's an interesting perspective that I've never thought of before. I do agree that all the maths we are taught (in high school) is too slow. I think it makes maths seem boring, as well as possibly making it harder to get a proper grasp of the subject. There are some countries where high school academic life is more, well, more academic. They work harder, for longer hours, and at more advanced topics. It's a shame it's not like that in the UK.