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How to walk through walls using the 4th dimension [video]

marctenbosch.com

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Re: How to walk through walls using the 4th dimension [video]

#42
post #36
post #33

If this topic interests you, you should definitely check "Imagining the Tenth Dimension" https://www.youtube.com/watch?v=zqeqW3g8N2Q

That video is incoherent nonsense, especially from the '5th dimension' and onwards, and in no way resembles the modern understanding of dimensions in physics or mathematics. I wouldn't bother watching it except for entertainment.

Care to expand? I'm not sure if it is possible to imagine these dimensions with the "modern understanding of dimensions in physics or mathematics", but it would be nice to at least know why this way is incorrect

Re: How to walk through walls using the 4th dimension [video]

#43

I was really hoping for a continuous (rather than discrete) fourth dimension. The concept is cool and looks to be well executed, but it's not very different from other alternate reality implementations such as the Dark World in Legend of Zelda.

That would be really cool. The mathematics involved don't seem too difficult; you have to add another axis to your vectors, points, and transform matrices, and you can place and orient your models in 4D space, set up lights and a camera in 4D space, and project the camera's view into 3D space first then onto the 2D display. I think the hard part is creating the models and writing the rendering engine. Creating 4D mod…

I believe there are some good libraries out there for handling quaternions. Can't remember the topic but there was a discussion here within the last 10 days about their application to a similar problem.

Re: How to walk through walls using the 4th dimension [video]

#44
post #36

Earlier quoted context omitted.

That video is incoherent nonsense, especially from the '5th dimension' and onwards, and in no way resembles the modern understanding of dimensions in physics or mathematics. I wouldn't bother watching it except for entertainment.

Care to expand? I'm not sure if it is possible to imagine these dimensions with the "modern understanding of dimensions in physics or mathematics", but it would be nice to at least know why this way is incorrect

One could waste one's entire life trying to correct rubbish attempts at physics on the internet, especially when it's full of non-sequiturs like the video. But as a start, the description of quantum mechanics is nonsense and I'm guessing the narrator got their understanding of it by reading popsci books (I'm trying to avoid a personal attack on the author, but it's hard when they've said a lot of wrong things so very confidently). The dimensionality of a typical QM Hilbert space is infinite, not five. People get wound up wondering what the N^th dimension is, when all dimensionality is, somewhat simplified, is how many numbers you need to describe the position of something.

The top comment on this stack exchange thread has more: http://physics.stackexchange.com/questions/55824/is-imaginin...

Re: How to walk through walls using the 4th dimension [video]

#45
Looks like a neat game, but I'm skeptical how it would work in reality. For example, it looks like the 4th dimension (time) gets frozen (for the observer) when you want to traverse it. That means, the second you 'travel in time,' the Earth, at its current velocity, would already be 30km away.

Re: How to walk through walls using the 4th dimension [video]

#46
post #28
post #26

Earlier quoted context omitted.

What would the 4th dimension coordinate of your models even represent, though? I'm having trouble wrapping my head around it.

Mathematically, they're identical to any other dimension. You can move a little bit into a fourth dimension just like moving a little bit left-to-right. Or you can rotate things around the fourth axis just like turning something clockwise. In the case of this game, he only shows a 2D projection of a 3D cross-section of a 4D world, so that might be adding to the confusion. What you see in the video is only 3D "slices"…

Would something like an Oculus Rift VR help reduce the number of projections from being "4D->2D" to be "4D->3D"?

Re: How to walk through walls using the 4th dimension [video]

#47
post #45

Looks like a neat game, but I'm skeptical how it would work in reality. For example, it looks like the 4th dimension (time) gets frozen (for the observer) when you want to traverse it. That means, the second you 'travel in time,' the Earth, at its current velocity, would already be 30km away.

... or did the rest of the universe move 30km the other way? :)

Re: How to walk through walls using the 4th dimension [video]

#48
post #27
post #16

This is a very interesting way of explaining the 4th dimension by relating it to the difference between the 2nd and 3rd dimensions. However, I think what would really solidify my understanding is to see the 4D level editor. I'm not sure how truly 4D this world is, but it appears to let you switch between a fixed set of different 4 dimensional positions, each of which has a different 3D representation. Just as a plane…

That's not quite what a 4th dimension is like. In your example, the faces are completely separate from one another. But really they would be connected, in a continuous line. You'd be able to push something a little bit along the dimension, or run a long distance. You could rotate an object in 4D so that parts of it ware poking a little bit into each dimension at the same time.

  > That's not quite what a 4th dimension is like.
Of course not. You'll notice that I questioned how truly 4D the game was and said the game appears to have fixed sets of 4D positions (ie: not a continuous range). I also said that my example was fake 4D. If the developer were to show the level editor, I suspect that we'd see it's not really 4D at all, but my fake approximation of 4D via a fixed number of 3D environments that the player can transition between.

Re: How to walk through walls using the 4th dimension [video]

#49

The game looks fascinating. I'm still trying to get my had around the analogies, but get the feeling that playing the game for real will bring a level of intuition to the experience. In the meanwhile, can anyone help me out? In the 2D->3D example, you have one shared axis (Z -- vertical), and an alternating pair for the second axis (X and Y -- horizontal). In effect, from the 2D character's point of view, 'jumping' i…

The plane exists - it is passing through the character body (perpendicular to the ground) and parallel to the desert, grass border in the example video.

You can see when the 4D rotation occurs there, that in that plane, everything stays constant (e.g. rocks stay there, trees, etc.) You just look at the objects from different angles as it rotates.

Edit: Link to the relevant point in the video - https://www.youtube.com/watch?v=9yW--eQaA2I#t=148

Re: How to walk through walls using the 4th dimension [video]

#50
post #46
post #28

Earlier quoted context omitted.

Mathematically, they're identical to any other dimension. You can move a little bit into a fourth dimension just like moving a little bit left-to-right. Or you can rotate things around the fourth axis just like turning something clockwise. In the case of this game, he only shows a 2D projection of a 3D cross-section of a 4D world, so that might be adding to the confusion. What you see in the video is only 3D "slices"…

Would something like an Oculus Rift VR help reduce the number of projections from being "4D->2D" to be "4D->3D"?

No, Oculus Rift's screens are still 2D surfaces.
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