Comment author: DanielLC 17 September 2014 11:45:56PM 2 points [-]

Actually from the point of view of the ladder the universe still repeats at every ten feet.

No, it does not. I think I messed up before and it's actually 20 feet and 8.8 nanoseconds. From the the point of view of the garage, the coordinates (0 ft, 0 ns) and (10 ft, 0 ns) correspond to the same event. From the point of view of the ladder, the coordinates became (0 ft, 0 ns) and (20 ft, 8.8 ns). They still have to be the same event.

The universe is definitely repeating itself to be off by a certain time, and the distance it is off by is not ten feet.

Comment author: Slider 18 September 2014 12:32:41AM 1 point [-]

The ladder sees the carage length contract. That is less than 10 feet. The ladder doesn't see itself contract that puts the limit on the repeating of the universe.

Are you sure the ladder point equivalences are not (0 ft, 0ns) and (20 ft, -8.8ns)?

Comment author: DanielLC 17 September 2014 05:32:22PM 3 points [-]

Actually that's not a big deal. Technically you need general relativity to do that, but it's just a quotient space on special relativity. In any case, it works out exactly the same as an infinite series of ladders and garages.

There is one thing you have to be careful about. From the rest frame, the universe could be described as repeating itself every, say, ten feet. But from the point of view of the ladder, it's repeating itself every five feet and 8.8 nanoseconds. That is, if you move five feet, you'll be in the same place, but your clock will be off by 8.8 nanoseconds.

Comment author: Slider 17 September 2014 10:55:02PM 0 points [-]

Actually from the point of view of the ladder the universe still repeats at every ten feet. It is just that from it's point of view it takes the space of two carages at any one instant.Both the garage and ladder are in a state of rest and show equally good times. Yes they read different but doesn't mean they are in error.

I am not sure whether it would see other instances of itself. I only spesified a spatial gluing and not that the garage be split into timeslices. I guess that the change of the point of view has changed some of that gluing to be from future to past. For if the ladder would be too long the frontend would not crash to the same ladder time backend but to a future one. (ignoring the problem of how you would try to slide the ladder into too small a hole in the first place)

Comment author: DanielLC 16 September 2014 03:54:30PM 2 points [-]

In the normal example, where the ladder is straight and moving forward, it has only one reference frame. Strictly speaking, each rung has a different reference frame, but they differ only by translation.

From what I understand, you modified it to a circular ladder spinning in a circular garage. In this case, each rung is moving in a different direction, and therefore at a different velocity. Thus, each rung has its own reference frame.

Comment author: Slider 16 September 2014 11:52:23PM 0 points [-]

ah, I meant to glue the end and start together without curved shape/motion. But I guess that is physically unrealisable and potentially more distracting than explanatory.

Comment author: DanielLC 15 September 2014 10:49:03PM 1 point [-]

Why have that definition of "fit"? I could eqaully well say that fitting means that there is a reference frame that has a time where the ladder is completely inside.

In that case, the ladder fits.

From the point of the ladder

Each rung of the ladder has a distinct reference frame. "From the point of the ladder" is meaningless.

Comment author: Slider 16 September 2014 09:03:28AM 0 points [-]

If the ladder point of view is ildefined so is the garage point of view as the front and back of the garage have distinct reference frames. Any inertial reference frame is equally good. The ladder is not accelerating thus inertial. In the sense that we can talk of any frame as more than a single event or world line the ladder frame is perfectly good.

Comment author: Thomas 15 September 2014 08:52:26PM 0 points [-]

Place red and white equilength rulers on the edge of the cylinder. The rotating cylinder will have more and shorther rulers.

They will multiply as the orbital speed increases? Say that Arab numerals are written on the rulers. Say that they are 77 at the beginning. Will this system know when to engage the number 78?

Or will there be two 57 at first? Or how is it going to be?

Comment author: Slider 15 September 2014 09:19:47PM 3 points [-]

I was thinking of already spun cylinder and then adding the sticks by accelerating them to place.

If you had the same sticks already in place the stick would feel a stretch. If they resist this stretch they will pull apart so there will be bigger gaps between them. For separate measuring sticks they have no tensile strenght in the gaps between them. However if you had a measuring rope with continous tensile strenght and at a beginning / end point where the start would be fixed but new rope could freely be pulled from the end point you would see the numbers increase (much like waist measurements when getting fatter). However the purpoted cylinder has maximum tensile strenght anywhere continously. Thus that strenght would actually work against the rotating force making it resist rotation. a non-rigid body will rupture and start to look like a star.

So no there would not be duplicate sticks but yes the rope would know to engage number 78.

If you would fill up a rotating cylinder with sticks and spin it down the stick would press against each other crushing to a smaller lenght. A measuring rope with a small pull to accept loose rope would reel in. A non-rigid body slowing down would spit-out material in bursts that might come resemble volcanoes.

Comment author: Slider 15 September 2014 08:45:40PM 14 points [-]

The negation that "Popular ideas attract disproportionally good advocates" seems also worth attention. People accept sloppy thinking a lot more readily if they agree with the conlusion. This can be used as a dark art where you present a sloppy thinking argument for obvious truth or uplifting conlusion and then proceed to use the same technique to support the payload. The target is less likely to successfully deploy resistance.

Also it's quite often that a result that is produced in a rigorous way is rederived in a sloppy way by those that are told about the result.

Comment author: shminux 15 September 2014 03:44:01PM 47 points [-]

There is no territory, it's maps all the way down.

Comment author: Slider 15 September 2014 08:30:07PM 1 point [-]

Every computation requires something that instatiates it, ie a abstract or concrete machine to run on. In a very extreme case you might come up with a very abstract idea. However then the instation provider is the imaginer. Every bit of information requires a transfer of energy. Instation is transitive relation. If there is simulation of me it neccesarily instanties my thoughts too.

Also the parent comment implies a belief in panpsychisism.

Comment author: Jiro 15 September 2014 07:46:50PM *  0 points [-]

Saying that a moving ladder "fits" means that the start of the ladder is in the garage at the same time that the end of the ladder is. If the ladder is moving and contracted because of relativity, these two events are not simultaneous in all reference frames. Thus, you cannot definitely say that the moving ladder fits--whether it fits depends on your reference frame. (In another reference frame you would see the ladder longer than the garage, but you would also see the start of the ladder pass out of the garage before the end of the ladder passes into it.)

Comment author: Slider 15 September 2014 08:07:39PM *  1 point [-]

Why have that definition of "fit"? I could eqaully well say that fitting means that there is a reference frame that has a time where the ladder is completely inside.

If you had the carage loop back so that the end would be glued to the start you could still spin the ladder inside it. From the point of the ladder it would appear to need to pass the garage multiple times to oene fit ladder lenght but from the outside it would appear as if the ladder fits within one loop completely. With either perspective the one garage space enough to contain the ladder without collisions. In this way it most definetly fits. Usually garages are thought to be space-limited but not time limited. Thus the eating of the time-dimension is a perfectly valid way of staying within the spatial limits.

edit: actually there is a godo reazson to priviledge the rest frame oft he garage as the one that count as ragardst to fitting as then all of the fitting happens within its space and time.

Comment author: Thomas 15 September 2014 06:21:43PM 1 point [-]

I have two photos of two different pies, one of rotating one and one of not rotating. Photos are indistinguishable, I can't tell which is which.

On the other hand, both pies have one-to-one correspondence with photos an one should be slightly deformed on the edge.

Even if it is, on the photo can't be. The photo is perfectly Euclidean. I have measured no Lorentz contraction.

Comment author: Slider 15 September 2014 07:41:24PM 1 point [-]

Place red and white equilength rulers on the edge of the cylinder. The rotating cylinder will have more and shorther rulers. Thus the photos are not the same. Even better have the cylinder slowly pulse in different colors. The edges will pulse more slowly thus not being in synch with the center.

Related phenomenon is that moving ladders fit into garages that stationary ones would not.

Comment author: Slider 15 September 2014 07:12:26PM 4 points [-]

Friendliness by mathematical proof about exact trustworthiness of future computing principles is misguided.

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