Relative Motion (A Thought Experiment)

One of the things that I'd remind the folk working with me was that "I was in the position primarily because I had screwed up more often than all of them combined."The advantage of having made mistakes is one of the greatest assets possible.It might be fun to have a thread where some of us could point out some of our great ideas over the years that turned out to be complete flops.

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Aslan is not a Tame Lion

Ok, I'm not too proud to admit that I had to Google that. The first computer I used in any serious way was an Amstrad PCW 8512 (that's spooky; I actually remember the number). Suffice it to say, it was a shitbox. Well in fairness, it did come in handy for assignments in high school, but that's about it. And even then, you wouldn't want them to be too long because it printed everything soooooooo sloooooooowly. It was basically just a glorified typewriter.I'm sure that when it first came out it was good enough but really...I mean, even back in the days I was using it for school there were better computers around. Hell, I remember seeing more impressive stuff on the Apple computers they had at my primary school.In retrospect, I think it must have already been outmoded when we bought it. Either that or the manufacturers just forgot to make a computer that could actually do something. Piece of crap. By the time we were finished with it we couldn't even give the damn thing away; nobody wanted it! Can't really say I blame them. Well then it's official; you're smarter than me. I tried to teach myself some C a couple of years ago and let's just say that I can write exactly the same number of C programs now as I could before I started studying. Glad to see you caught on to the important side of that equation; experience. To quote myself with added emphasis, "I respect age and experience."The point being that anyone can get old but I greatly admire those who gain experience with age, especially those who seek to learn and understand. That's why I respect you so much; you've put (and continue to put) your years to good use and have the knowledge to show for it. All going well, you're how I imagine myself to be some day. At least, I hope so. Heh, you needn't worry about that. You've probably already noticed that I have this insatiable need to understand why things are the way they are. Hence, I am rarely satisfied with something until I understand it.It can be quite frustrating in fact. This thread is a perfect example; this puzzle has been gnawing away at me for years, and where many people would probably have had the good sense to say, "Well who really cares?" by now, I stubbornly persist in trying to comprehend it.Much like my exchange with Rrhain regarding multiple dimensions in these three posts (subtle hint to anyone who may be able to assist me with this). In that case, I actually had long since given up. Then I came across our resident mathematical Mozart.In any case, don't worry; I question. Not to be argumentative, though. I often fear that I may come across that way but this isn't the case; I don't question things the way I do out of distrust, but out of a desire to understand. For some reason, it's not enough that others understand something, I want to understand too. Just the way my mind is wired, I guess. Indeed. I would dare say that, at 26, I have probably done more thinking than many (perhaps even most) other people my age. Not to sound too vain, mind you. On the contrary, some will tell you I just have too much time on my hands.Incidentally Ned, I'm enjoying our chat but I can't help wonder, am I going the right way to incur the wrath of your alter ego? If so I'll desist. As I'm sure you can see I'm more than capable of talking at length and I don't want to get in trouble for going off topic, much less having long, irrelevant conversations; comprehensive enough, just not with regard to the topic of the thread.

...it's my fault. I started it by asking Ned about his field of expertise.I don't suppose you have any thoughts regarding my dilemma, in this thread? If not that's cool. Either way, feel free to chat away or whatever. As you were.

I think this thread kinda ground to a halt anyway. I wish Eta had chimed in with something though.Besides if we are talking about my good buddy Ned I don't mind wandering way off topic. Now we'll both get warned (or worse) by someone.

I was the only one in my high school who used a sliderule (google that ). I remember the shock that I felt when my kid brother was in grade 11 (he's 18 years younger than I) and looked at me kinda shocked with: "You mean they didn't have calculators when you were in high school?" I grew 10 more grey hairs right then. Flattery will get you anything; but the answer to your relative motion question. I'll ask the next time I run into a physicist acquaintance. He works here at UBC and at CERN on one of the big detectors (I have to find out which one).I've written in a bunch of languages C is pretty simple. C++ is fun but has a pathilogically designed syntax. They made a mistake trying to make it be just what it is named "C and one more". You should know, before you overestimate how smart I am, that I went for months using C++ before, one day, walking down the hall, the reason for the name dawned on me. Everyone else looked at me with disgust when I unvailed my revalation. There were a number of occasions where the engineers working for me offered up "Well, that's why you are a manager.". This was one of them.BTW, I've tried to visualize 4 space a number of times. It doesn't work for me. But then I'm not much of a mathematician.

Yes, I know. I was also hoping to hear from him.Eta, if you're reading this I'd very much welcome your input. I realize you're probably a busy person so please don't feel as though you have to type a long, detailed explanation; I would be most grateful for anything at all.In fact, even if you just refer me to some sites or URL's pertinent to this thought experiment, I would be very appreciative. If you know of any online sources where I could research the topic further, that would be terrific.I really hope to hear from you, Eta. I understand, though, if you are too busy; it's not a problem. Either way, thanks for your time. He is a grand chap, isn't he AdminNosy? Soooo...our off-topic chatting is ok then?Well, assuming I read that correctly, I suppose I'll continue (carefully) for the time being. Who knows?...Eta or someone else may still pop their head in at some point.

Heh, no need; I actually know what that is. I feel every bit of my age when I visit video game forums and see teenagers talking about playing "old" games on the original Playstation "when they were a kid." Well I still very clearly remember getting my Atari when I was a kid. Upon informing modern youth of this fact, I have on occasion actually been met with, "What's an Atari?" Seriously? Thanks Ned! I really appreciate that! If it'll help explain my problem to him, you're more than welcome to save or print out any of my posts for him to read (or even give him the URL if it's easier). Again, thank you very much! You know, now that I think about it, I'm not even sure which one it was that I was trying to learn; kind of shows how much I retained from my study, doesn't it? I know it was one of those but I'm not sure which. I recall looking over both before picking one but it didn't really mean much since I didn't know what I was looking at anyway. In retrospect, I think it was actually C++ that I went with.Today, all I know of programming are very tiny fragments. I understand (more or less) how it works but I don't remember much of anything with regard to any languages.I recall a few commands in BASIC (from my old Amstrad days, no less) and even did a little programming in high school; Pascal if memory serves but don't quote me on that. But aside from that (which is patchy anyway) all I really know now is a little HTML and I'm not even sure if HTML is actually considered a "programming language" per se. Oh you actually read my exchange with Rrhain? Cool! And yes, it is a maddening task indeed. It's so frustrating to clearly understand the principle behind something, yet be totally powerless to actually comprehend it.At the risk of pushing my vanity meter through the roof, I do believe that I have a fairly solid grasp of at least the basic principles of dimensionality. However, as hard as I try, I simply cannot comprehend the reality of four (and more) spatial dimensions; I just can't get myself to "see" it.I was tossing around the idea of starting a new thread on this but I'm not sure if there would be any point; I really don't think this is something that Rrhain or anyone else is going to be able to teach me. I think it is something that will either come to you, or not; I doubt that it can simply be "taught".Still, it's a subject that fascinates me, no end. And it does seem to keep coming up on the forum. Perhaps, it would be good simply to have a generic dialogue on the topic. And who knows? In the process I may just have a revelation.

Hey Tony, I'll tell you what. Once I'm back sitting on my throne in heaven from my field trip here on Earth, you'll be the first sentient being to "know" everything I'll know about dimensions. Also, I'll be granting any request you have, so think hard about what you want. Who knows, I could have a fatal car accident tomorrow!

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The Laminator
For goodness's sake, please vote Democrat this November!

Hey cool! I can't help but wonder, what did I do to deserve this?Well anyway, hurry up and d......Um...I mean, thank you. No thought is necessary; I know exactly what I want, and it has nothing to do with understanding dimensions. It's a long and sad story, though, and doesn't quite adhere to the topic of the thread (not that we've let that stop us so far). I'll hold you to that, you know?

Hi cavediver.In case you missed it, you can find the first part of my reply here. I know what I'm like when I get distracted so I hope you don't mind me moving the rest of it here. I have a tendency to sidetrack discussions, as I demonstrated quite conclusively in this very thread, no less. Yes, but isn't acceleration itself relative? I don't see how it can make any more sense than "motion" without another reference frame to be accelerating relative to. See, this is what I can't get my head around. Why are there consequences? What causes them? If a body in an otherwise empty universe displays, say, Coriolis forces, what is causing it? Its rotation? But what is there to distinguish it from a body simply sitting motionless in an otherwise empty universe? I know that one will display the effects of acceleration while the other will not, but it's their cause that I can't figure out. Acceleration is supposedly the cause but I can't see what "acceleration" can possibly mean without a relative frame of reference.I think one of my problems is that I don't really understand its nature even in a universe that does have other frames of reference. I mean, how are things physically different when these other reference frames are present? Does their mere existence physically "do" something that makes such acceleration possible? It seems almost like a philosophical musing, and in the case of simple motion I suppose it is, but acceleration has detectable consequences.The problem I think I'm having is that I can't see how acceleration can have any more meaning than motion without something to be accelerating relative to. How, for example, can our hypothetical planet's "rotation" make sense except in the comparative light of a relative reference frame? And if evidence of acceleration can be seen in a totally void (save for the planet itself) universe, does this mean that there is some kind of "absolute" reference frame relative to which it is rotating? Isn't this the very antithesis of Relativity? Indeed. I may be wrong but, the way I visualize it, a tidally-locked system (in an otherwise empty universe) would constitute a scenario with two distinct bodies, yet still only one reference frame. From either one, the other would appear to sit completely motionless in the sky.This was the source of my confusion; could they "orbit" each other, or, without a relative frame of reference, would they necessarily fall together? As before, if they could stay apart, what would this mean? That they were orbiting each other? Relative to what? Perhaps, but the point of this scenario is that there is nothing at a distance (save for empty space). If, for example, you get in a ship and fly out to a position that gives you an overall view of the system's mutual orbit, have you not essentially created a relative frame of reference?What I'm trying to figure out is whether or not this can happen without any such reference frame. In essence, the two "orbiting" bodies in this scenario (and any inhabitants) are all there is. There is no other position (short of flying a ship away from the system) from which you can overlook the system, as a whole, to see if the bodies orbit each other. The only vantage points are the bodies themselves, and, from either one, the other appears completely at rest. You mean because of the equivalence of gravity and acceleration? By definition, a body that remains at a fixed distance from the mass it orbits is not accelerating, correct?Or are you referring to the "free-fall" aspect? That is, the fact that an orbiting body is essentially in the process of falling endlessly around the gravitating mass, but never reaching it, as the surface itself falls away at a rate equal to the velocity of the orbiting body's descent?Actually, now that I think about it, both of these descriptions seem to be just different ways of phrasing exactly the same thing. Is this what you mean by "not accelerating" or have I gone awry somewhere? Also, why does this only apply to objects that are "small enough"? I'm afraid you lost me there.

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Actually, now that I think about it, both of these descriptions seem to be just different ways of phrasing exactly the same thing. Is this what you mean by "not accelerating" or have I gone awry somewhere? Also, why does this only apply to objects that are "small enough"? I'm afraid you lost me there.

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It only happens to objects which are small enough because large objects will have enough volume so that different sections of them are significantly closer or further from the gravitating body so that they have different accelerations.

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Yes, but isn't acceleration itself relative? I don't see how it can make any more sense than "motion" without another reference frame to be accelerating relative to.
The problem I think I'm having is that I can't see how acceleration can have any more meaning than motion without something to be accelerating relative to.

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Acceleration is basically moving between reference frames, going from one velocity relative to a given observer to another.
So any observer will see you change speed, in a sense it is observable to all observers including yourself, where as velocity isn't.