# I How would a 4th Dimensional Object Move?

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1. May 17, 2017

### Blop

I want to know how a 4D object, (specifically a tesseract) would move in the space of t, not x, y or z.

2. May 17, 2017

### Staff: Mentor

It doesn't. A 4D object is a fixed figure in a 4D space. Just like a given triangle is a fixed figure on a 2D sheet of paper.

3. May 17, 2017

### cosmik debris

A path in 4D, and I'm assuming you're referring to Spacetime not a Euclidean space, is a world line. So it doesn't move it exists. Some authors do refer to things moving along a world line but I think this is for practicality.

Cheers

4. May 26, 2017

### ImStein

Good point, cosmik debris. The object, continuum and "motion" if not given, will be presumed to be particles (or composites) from the Standard Model, 4D of spacetime (3+1) and velocity in distance/time respectively. Worldlines in a Minkowski spacetime diagram don't themselves move but they do indicate relative velocity as the inverse of slope in that reference frame.

One might construe the "movement" of a worldline but it would have to be defined as some kind of hyper-velocity*. I can imagine a use for such a construct in quantum mechanics, as it relates to phenomena where a single particle seems to pass through two slits at once. That is, to ascribe a wave nature to a particle.

*The term "hypervelocity" is however, already in use to indicate those > 3,000 m/sec.