Dimensions

YouTube video — Neil deGrasse explains Dimensions

A summary of the four dimensions and their characteristics as explained by Neil deGrasse:

One-Dimensional Space: This dimension is represented as a line, where the only measure is length. There is no width or depth, just a straightforward, singular dimension. In this context, entities would have no volume or area, just length.
Two-Dimensional Space: By adding another dimension to the one-dimensional line, we create a plane, characterized by two measurements: length and width (referred to as the X and Y axes). This plane allows for shapes like squares and circles. In a two-dimensional world, beings would perceive each other only by their outlines, as they wouldn’t have the ability to see inside or beyond the flat surface they inhabit. Medical surgery in such a universe would require opening the perimeter (outline) to access the inside, as there is no concept of ‘above’ or ‘below’ in a flat world.
Three-Dimensional Space: This is the space we are familiar with, having length, width, and height (X, Y, and Z axes). It allows for volume and depth, making it possible to see the outer surface of objects and beings, and to look inside them from above or below the two-dimensional plane. In this dimension, surgery requires opening the outer skin to access the internals, unlike in a two-dimensional world where you’d open the perimeter.
Four-Dimensional Space: While often related to time in physics, here it’s discussed as a spatial dimension in addition to the three spatial dimensions we experience. A being from a four-dimensional space could view all three dimensions from a new perspective and interact with them in ways we can’t comprehend, similar to how a three-dimensional being can view and interact with a two-dimensional plane. For instance, a four-dimensional being could perform “dimensional surgery” without making physical incisions in our three-dimensional space.

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