Speed of Light Barrier

I don't know if this is quite what you're asking but it was a great help to me in better understanding the light-speed barrier. I wrote about it in another post and, while it specifically deals with time dilation, it indirectly presents a fairly intuitive analogy of how the light-speed barrier works. I'll quote the relevant portion here. So long as we're touching on this again I'd like to ask the resident physicists... Just how close is this analogy to the actual process? It is the best (read: most easily-perceptible) model of time dilation/the light-speed barrier that I've ever read, but is it an accurate illustration of what actually happens? Does mass indeed have an unchanging "reserve" of velocity that it shares between space and time, such that one must fall if the other rises and vice versa?

Hi cavediver. I apologize if I gave the impression that I personally thought it was flawed. That truly wasn't my intention. The reason I asked is because, in my experience, such explanations are usually simplified descriptions which are specifically designed to be more palatable to our intuitive way of thinking than the actual descriptions otherwise would be. As such, they often convey a more intuitive sense of what is happening at the expense of total accuracy.But this is just something that I'm cautious about. As a scientific layman, I try to be careful not to take these kinds of analogies too literally, lest I get a skewed idea of the actual models. As I've said previously, it's frustrating not understanding the underlying mathematical theory. Mathematically, the models can be shown with such accuracy, yet when asking what the math "really" means, it so often has to be translated via statements like, "Well... Try to think about it like this..."Anyway, my point is that I'm just wary of how closely I associate intuitive physical analogies with the actual phenomena they describe. It seems, from what I've heard, that the only way to really understand certain physical models is mathematically.That said, if this analogy is indeed an accurate description of the actual model, that's great. It gave me a deeper insight into the process than any other description I've ever read, so I'm pleased to hear that I have the correct understanding.I also appreciate your explanation of the "reserve" of velocity. I couldn't really think of any other way to phrase this, but no problem; your description was very much along the lines I was thinking. Thanks for the confirmation. Off-topic here, but you've just touched on my personal obsession. You seem quite knowledgeable of this so, if you can help me in any way, please feel free to contribute your own thoughts. I'm always on the lookout for anybody I can learn from in this area.

Hi cavediver. Again, I apologize for my lack of clarity. I wasn't referring to your description; I was referring to Greene's. The cars racing across the desert is clearly a "commonplace" illustration that Greene uses to describe the actual phenomenon in a more easily-perceivable way. It was this description to which the word "analogy" was directed.If I've understood you correctly, though, Greene's analogy very closely reflects the actual model anyway. Your description is exactly the impression I got from Greene's cars. So it seems that I did understand it correctly. I was, perhaps, just not explaining it well (the "velocity vector," for example, being a more useful description than the "reserve of velocity"). Ugh! I know; it's frustrating. I wish I did understand the math. Unfortunately, like many amateur scientists, I rely on the nearest approximations that can be described in physical terms to understand the models. As a rule, if it can be described in a way that I can somehow picture in my head, I can understand it within reason. If it can only be shown through abstract mathematics, though, I'm pretty much screwed.I find it to be a kind of double-edged sword, really. I like descriptions, such as Greene's cars, that are clear and easy to understand. At the same time, though, I worry that the more simplified the description (for ease of understanding), the less accurate it will be in describing the actual model. It's tough trying to understand physics purely through the concepts themselves, and knowing none of the math. Oh, please don't let that stop you. Unless it's been closed unbeknownst to me, you should still be able to post there. If you have anything you can add to it you're more than welcome. So I understand. From what I've heard, performing mathematical calculations in more than three dimensions is not the least bit unusual. Three dimensions or three hundred dimensions... they're all just numbers as far as the math is concerned. Heh heh!Well, I haven't devoted that much time to it, but I have devoted quite a bit. I've been fascinated by dimensional concepts for many years now and I've read a lot of material on the subject. I still know essentially nothing of the math, but I do believe I have a fairly solid grasp of the basic principles (at least for a layman). Hmm... Could be worth a try. Thanks for the recommendation.Just to be clear, though, my interest is not really in the underlying mathematics; it is to gain a clearer physical perception of higher dimensions. My ultimate goal, though a long shot admittedly, is to achieve the same intuitive perception of four-space that I have of three-space.

Hi cavediver. No problem. You're relatively new around these parts so I just wanted you to know that I don't really debate or argue here. I don't post a great deal but, when I do, my only purpose is to learn.If you're interested, I've previously started a number of threads on various topics of interest to me. Dimensional Discourse you already know about. There is also Relative Motion (A Thought Experiment), First confirmed image of extrasolar planet, and The resilience of matter's fundamental components. Not that I'm trying to monopolize your time or anything. You're not the first educated person I've latched onto and said, "Teach me!" Yes. The deeper I dig, the more I get the impression that common intuition simply can't take you beyond a certain point. For those of us that don't have the requisite grounding in mathematics, things make progressively less and less sense the further you go. I don't know if this is different for those like yourself, but I would imagine that, at the very least, the concepts that they come up against aren't totally opposed to their intuition precisely because part of their way of thinking is based on the math. Yes! I have, indeed! Unsuccessfully... grr!!I seem to recall, once, reading an "explanation" of the exchange of gravitons. It used the analogy of two people standing on skateboards (or in boats, or some such...too long ago to remember exactly) throwing a ball back and forth to each other. The point was to demonstrate that this will cause them to gradually move apart and, thus, show how one body can affect another by exchanging particles.Now, if you're sitting there rolling your eyes, don't worry; I can see that this is a pretty lousy analogy, for numerous reasons. Not the least of which is the fact that it doesn't actually explain gravitational attraction. In fact, I'm not even sure it would make a decent analogy of repulsive forces. I somehow doubt that repulsion between, say, bodies of alike electric charge is caused by the emanation of the carrier particles physically nudging the bodies apart in a Newtonian "equal-and-opposite-reaction" kind of way. Well, I suppose since the universe feels no need to conform to our intuition in so many other aspects, why should its dimensional properties be any different? Ha! You know, even as I typed that, I thought I should have clarified it more!Let's just say that it's my current ultimate goal (oxymoron alert ).Or, to put it another way, I currently have my sights set on four. If such a time comes that I achieve my comprehension of that, I will re-evaluate and, perhaps, aim for the same understanding of five...and so on, indefinitely.Of course, this is hardly an urgent concern in my mind as I am, thus far, in absolutely no danger of acquiring the comprehension that I seek. In all honesty, not to be pessimistic, but I have come to accept that I may never achieve this particular goal. That won't stop me trying, of course, but it seems that there are very few who can do it. And, from what I've seen, they always seem to be either physics or mathematics majors (or both) which doesn't bode well for the chances of a layman like myself.

Or your destination to be there when you arrive.I've always considered our universe to have a kind of sick sense of humour, in this regard. "Sure, you can travel to the other side of the cosmos in less than a day ship time. Of course, the universe itself will have experienced heat death by then... but hey, at least it's only been a day for you!"Lousy universe.

Well, I was trying not to derail the discussion too much but it seems like the thread has fallen by the wayside anyway, so I'll reply here after all... at least in part. If you're referring to "Relative Motion" that was my first thread. I had posted before that but that was the first topic of my own that I started. I figured it was a good place to start as that particular question had bugged me for years (and still does). Indeed. I realize that one doesn't truly understand these things without years of dedicated study.As a layman, it can be quite tough finding people to converse with. I seem to be in a kind of scientific No Man's Land. I understand enough that those I know in day-to-day life usually haven't a clue what the hell I'm talking about, but not enough to be able to get into the really juicy stuff when talking to the experts. Why, thank you!I do have a talent for asking questions that defy brief, easy-to-understand explanations, don't I?It does seem that this thread has lost "momentum" (*cough* sorry ) anyway, but in the interest of keeping everything where it belongs, I'll paste the rest of my reply into the other one. As I said before, it was the first thread that I started on EvC, and it's long since fallen waaaaay down, so this is going to be quite a bump.EDIT: 'Tis done! If you're interested, cavediver, you can see the rest of my reply here.This message has been edited by Tony650, 08-01-2005 12:07 PM