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A Time Machine
How about a machine that allows one to travel through time? | |
You could build a tube with the diameter of the planet Jupiter and as long as the solar system is wide. Then you could rotate it at just under the speed of light. Then you could fly your space ship across its transverse axis.
That would work, wouldn't it?
Amazon.co.uk: "How to Build a Time Machine"
http://www.amazon.c...avies/dp/0670030635
One of many pop-sci books on similar subjects. [zen_tom, Sep 10 2009]
view inside the tube
http://www.youtube....watch?v=wRhPM2wMzH8
[jaksplat, Sep 10 2009]
[link]
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Not so much a thought experiment as a single neuron misfire. |
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Personally, I prefer the time-travel products of the better
Italian vineyards. |
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All powered by billions of hamsters in tiny spacesuits and amped up on crystal meth. |
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No, it won't work; you'll poke someone's eye out. |
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// marked for tagline.
Added. |
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I think the poster is trying to explain something that might be an interesting thought experiment or paradox, but it's not getting through. More slowly, and from the start - and where does Jupiter come in? What does any of this have to do with time travel? |
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This is not a new idea though, is it? |
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I'd guess there is not enough mass in the solar system to build such a tube. |
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The centripetal force needed to keep it in one piece would be prohibitive too, but let's not be hindered by impossibilities: What would the spaceship do, traversing the tube while it rotates (presumably at the tip) with near-light speed? |
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rotating at the speed of bullshit |
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"Oh, my God, it's full of crap!" |
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It worked! I've travelled 15 seconds into the future while reading this idea! |
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Cosmic construction of a time machine has come up years ago (I think it is discussed in "A Brief History of Time") where a black hole is rapidly rotated about its axis, space time is warped into a sort of vortex form, and this particular warping means that it may become possible to cross the most enwarped areas of spacetime near the rim of the black hole in an unusual manner, allowing you to emerge at some time prior to going in. |
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I think you're missing something of suitable mass that you'd need in order to warp spacetime (a tube just ain't gonna do it) |
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It's a kind of Tiger Soup recipe, since all you have to do is find a super-massive black hole, and then simply rotate it at speeds approaching c. Even then, you'll never be able to use your black hole time machine to travel back to a time before your machine existed, so anyone who builds such a thing isn't likely to benefit from its construction. And then, due to the spacetime warping nature of such a construction, you probably wont want it anywhere near any inhabited solar systems, effectively forcing it to be located somewhere not entirely convenient, further limiting its usage to creatures with galactic travel capabilities and particularly long lifespans. |
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Anyway, so while interesting - it's not necessarily a particularly new idea or invention - there's a fair amount already published in the popular science genre that pretty much covers the ideas outlined here (great big spinning contraptions that may or may not have time-travel capabilities) |
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I don't think anyone can find a link to any previous spinning tube idea so that makes this an original invention. |
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Spin tube with ship inside and watch what happens when ship flies from one end to another. Maybe nothing, maybe something, either way an interesting thought experiment. |
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If [unfettered] would have been the first to think of the rigid scissors idea and posted it here you would have said it wasn't a new idea or invention because we already knew about the rigid rod? Come on. |
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[unfettered] you get my bun but in all fairness, maybe next time you can actually put some effort in writing your idea. Why don't you check out some of [Vernon] 's ideas to see the opposite of your spectrum. |
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[zeno] I see what you're saying. No, I can't think of anyone who's posited the idea of a time-travelling tube - probably because it's not going to do anything - smarties, pringles and other tube-based items are subject to the same laws of physics as unentubed objects and as far as I know, encasement in a tube (spinning or otherwise) has no overall effect on one's procedure through time. Of course, I could be wrong. |
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However, there ARE lots of great big spinning devices that use the warping of spacetime around a spinning black-hole (or wormhole in some cases) that have been thought of before - I wonder whether [unfettered] has been influenced by one of these (using your scissors analogy, perhaps [unfettered] has seen some actual hinged scissors, but is now suggesting that we carve a single-piece version from a single block of wood and see how that works) |
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Erm... We're already travleling through time.
(You can tell, because each of the letters of the previous sentence appeared in the order I intended)
Hang on a mo... you may have something there |
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If travelling through a tube was capable of causing you to travel through time at any rate faster than that which it currently passes then all subway trains would arrive early. |
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Therefore, this idea is bollocks. |
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are your train stations spinning? |
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Anyone, if [unfettered] by the facts, has potential to be a great inventor. |
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//We're already travleling through time. (You can tell, because each of the letters of the previous sentence appeared in the order I intended)//
So, the typo was deliberate? Or did we encounter a hiccough in the space-time wossisname? |
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I already have a functioning time machine. |
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It might be more interesting if it could operate at a rate other than 1. |
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My time machine informs me it's 1am and time I was asleep. It's usually right about these things. |
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//I don't think anyone can find a link to any previous spinning tube idea // |
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"Using massive spinning cylinders |
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Another approach, developed by Frank Tipler, involves a spinning cylinder. If a cylinder is long, and dense, and spins fast enough about its long axis, then a spaceship flying around the cylinder on a spiral path could travel back in time (or forward, depending on the direction of its spiral). However, the density and speed required is so great that ordinary matter is not strong enough to construct it. A similar device might be built from a cosmic string, but none are known to exist, and it doesn't seem to be possible to create a new cosmic string." |
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Granted, the mechanics are different. But there is a tube. And it spins. Basta cosi. |
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Where's the foetus going to gestate?... I mean, how do you control it? |
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Michio Kaku covered this in one of his books. The catch is that in order the theory to work, the tube has to be infinite in length. It's not easy to explain to [unfettered] exactly how much longer he needs to make his tube. Suffice it to say, quite a lot. |
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See? It is a good idea, not widely known to exist and no grounds for deletion. If would have been presented better or funnier it could rival moving fishbowl. |
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Let me get this straight... |
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1. You build a very long tube then set it rotating around its centre, end-for-end, such that the ends are travelling at light speed or faster. |
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2. You fly a spaceship into the tube (presumably at some point near the middle, as the ends would be going too fast to catch, unless you had a spacecraft capable of luminal or near-luminal speeds, rendering the tube unnecessary. |
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3. You then choose to go left or right, depending upon your desired destination. |
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4. You speed along the tube, presumably going ever faster because of the fact that the tube is moving faster, the farther you travel, due to its rotation (There's a problem with this bit, as I shall explain later). |
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Here's where I start having trouble with the idea:
A few scenarios... |
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Scenario A. You wish to go from point A, which is half of the length of the tube (radiusT) and directly along the X axis of the tube's rotation (let's say the tube is rotating along its Y axis) to point B, which is (radiusT) directly along the -X axis. There is no benefit to be had from passing through the tube at its centre of rotation, that I can discern, apart from the fact that crossing the swept path of the tube anywhere is inherently dangerous. |
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Scenario B. You wish to pass from any point with a spatial co-ordinate involving a Z axis component, to any other point involving a +Z or a -Z co-ordinate component and some +X, -X, +Y and/or -Y co-ordinate component. You may or may not derive a benefit from using the tube, in this scenario. |
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Scenario C. You wish to pass, ideally, from the location of the centre of the tube to a point on the circle its end describes, along the Y axis, in space, (i.e. 1 + 0.r x rT). You'll have to wait at 0, 0, 0 until the tube is at the right point in its cycle to allow you to set off and reach your desired destination. This could take a while. |
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You will derive a benefit from using the tube... until you have progressed far enough along the tube that its moment of rotation exceeds the capability of your ship to match its speed. At this point you must alight on the wall of the tube to avoid it smashing into your ship and turning you and your crewmates to strawberry jam. |
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Upon nearing your destination you must then exit the tube (remembering that you can't actually attain light speed through the propulsion of your ship alone). This will mean that you have to exit through the side of the tube. |
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However, if the tube is carrying you and your ship at any significant proportion of c then it will have increased considerably in mass (remember, we're dealing with the wacky physics of relativity here), so you'll need extremely powerful propulsion systems to allow you to blast off from the surface of the tube, in order to exit. Then you'll have to progress at your ship's maximum speed to your final destination. |
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In essence, this idea is a thought experiment and a particularly flawed one at that. |
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NoNoNo, you're getting it all wrong. |
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The tube is open at both ends and you are at one end, just inside the tube when it starts spinning. The end of the tube reaches a very high speed and so do you. You then start flying to the other end of the tube accelerating to the same high speed. When you get out at the other end you fly home and compare clocks. Clocks you put up all over the tube inside and out, in your ship, on different planets, everywhere. You then get your students to calculate which clock will show what time and why. A very difficult task. |
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The whole thing is slightly akin to the question what happens if you walk forward on a train that travels at lightspeed. Do you reach a speed of lightspeed plus walking speed? Another fine thoughtexperiment . |
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[zeno] the train example demonstrates just how strange the world is at near-light-speeds. If you are on a train and switch on a light in the centre of the train carriage, you will see the light illuminate both ends of the carriage simultaneously but an observer on the platform of a station watching the train pass by will see the light illuminate the rear of the carriage first. You will also see the station compressed in the direction of motion and the observer will see the train compressed in the direction of motion. |
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Are we on to Back to the Future III now? |
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[zeno] say you plotted your flight-path through the tube - and then repeated the same flight-path without there being a tube there - All the tube has done is provide a physical guide to following the flightpath proscibed by flying through a spinning tube. You could have used a spinning piece of string, or just some maths. |
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Is the tube important, or is it just the flightpath? |
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If the tube is important, why? And how? |
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And if it's just the flightpath, then what's so special about that? Couldn't you achieve the same thing by just flying round in a circle, or a straight line? |
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If the tube is traversed at the speed of light, it's
obviously not the bloody Jubilee Line. |
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You're mixing up frame of reference with physical reality. |
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If there's no physical connection between the tube and the ship then you get splattered unless you can keep up with its rotation. |
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If you enter through an open end of a tube travelling at light speed then you have to be travelling at light speed already or you'll get splattered as it comes on perpendicular to your direction of travel. |
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If you're already travelling at c then no tube is necessary. |
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You might get more buns if you scrap the tube and use an intergalactic trebuchet powered by a gravitationally-encapsulated black hole looped over a couple of skyhooks. |
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Mixing up frame of reference with physical reality. [marked-for-tagline] You're right, I was. |
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Haven't we already established that time doesn't exist? |
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Yes, but that was quite a while ago... |
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//Oh, my God, it's full of crap!// |
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//The whole thing is slightly akin to the question what happens if you walk forward on a train that travels at lightspeed. Do you reach a speed of lightspeed plus walking speed? Another fine thoughtexperiment .// |
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No. And you wouldn't notice anything peculiar at all. |
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