# The 4th Dimension: Exploring Human Curiosity & Its Theories

• _Mayday_
In summary, the conversation discusses the concept of dimensions and how it relates to the study of physics. It explains how physicists study events in space and time, requiring four dimensions to fully describe them. The discussion also mentions the possibility of higher dimensions and how they could potentially explain certain theories. The analogy of a being living in two dimensions and being trapped in a circle is used to illustrate the concept of a fourth spatial dimension.
_Mayday_
Hello, I am in the process of reading Black Holes, Wormholes & Time Machines and am somewhat confused, even though it is aimed at people like myself who have very little knowledge on the subject. I am reading about the 4th dimension now but I do not understand the relevance of researching into the 4th dimension or giving it a lot of thought. Jim Al-Khalilie, the author, has explained the fourth dimension as like being in a hollow sphere, and the fourth dimension would allow you to exit the sphere without getting any closer to any of the edges. What does knowing there is a fourth or second dimension universe mean? Is it just out of human curiosity or does it explain or help explain some theories. I'm really stuck here I am very interested in this subject, so do not think that I am saying it is useless because I have no idea really

_Mayday_

If this is in the wrong part of the site please let me know so I don't do it again...

A great example is the film "Time Machine" .. the time traveler is trapped inside a rock so he can not move but going forward on time (moving on the fourth dimension) he moves to a place where the rock has disappeared.

Real physics in 4-D implies no motion , perhaps 4 dimension exists or is just a physical artifact to describe nature, if we could 'see' in 4 dimension i believe that the mistery of QM and Relativity could be solved.

Note that a position-vs-time graph is a 4-dimensional "[mathematical] space".
In introductory physics, one often simplifies the discussion and considers only one-dimensional spatial motion (say, along a line)... which yields a position-vs-time graph that is 2-dimensional.

Are you clear on what "dimension" means? A dimension is just a number specifying a specific thing. To designate a specific point in space requires 3 numbers no matter what coordinate system you use- it is "three dimensional". Physicists study "events": things that happen at a specific place at a specific time. We require three numbers to specify the position in space and a fourth to designate the time. That is what Einstein meant when he said "Our universe is a four-dimensional space-time continuum.

It appears that the text you are referring to is talking about a possible 4th "space" dimension- that would be somewhat speculative. There are a number of theories that involve higher space dimensions but none of them have been shown to be experimentally "correct" (there isn't any question about a "second dimension"!).

The analogy with the hollow sphere is this- Suppose there existed a being that lived only in two dimesions- that could move about on a sheet of paper, that could move "up or down" or "left or right" but knew nothing about "vertical" direction. A circle containing that being would be a prison it could not get out of. But if the creature could move vertically, it would could move outside the circle. Similarly, if there were a fourth space dimension, a three dimensional person could move out of a hollow sphere.

mhill said:
A great example is the film "Time Machine" .. the time traveler is trapped inside a rock so he can not move but going forward on time (moving on the fourth dimension) he moves to a place where the rock has disappeared.
That wouldn't actually work if the rock is just moved rather than broken up into pieces. And that movie sucked.

HallsofIvy said:
Are you clear on what "dimension" means? A dimension is just a number specifying a specific thing. To designate a specific point in space requires 3 numbers no matter what coordinate system you use- it is "three dimensional". Physicists study "events": things that happen at a specific place at a specific time. We require three numbers to specify the position in space and a fourth to designate the time. That is what Einstein meant when he said "Our universe is a four-dimensional space-time continuum.

It appears that the text you are referring to is talking about a possible 4th "space" dimension- that would be somewhat speculative. There are a number of theories that involve higher space dimensions but none of them have been shown to be experimentally "correct" (there isn't any question about a "second dimension"!).

The analogy with the hollow sphere is this- Suppose there existed a being that lived only in two dimesions- that could move about on a sheet of paper, that could move "up or down" or "left or right" but knew nothing about "vertical" direction. A circle containing that being would be a prison it could not get out of. But if the creature could move vertically, it would could move outside the circle. Similarly, if there were a fourth space dimension, a three dimensional person could move out of a hollow sphere.

Thank you, that has certainly cleared things up.

## 1. What is the 4th dimension?

The 4th dimension is a theoretical concept in physics and mathematics that refers to a dimension beyond the three dimensions of length, width, and height. It is often represented as time, but there are also other theories that suggest the 4th dimension could be a spatial dimension.

## 2. How do we perceive the 4th dimension?

As humans, we can only perceive and experience three dimensions. We are unable to fully comprehend or visualize the 4th dimension, as it is beyond our physical abilities. However, we can understand and study it through mathematical and scientific theories.

## 3. What are some theories about the 4th dimension?

There are various theories about the 4th dimension, including the concept of time as the 4th dimension, the possibility of multiple parallel universes existing in the 4th dimension, and the theory of higher dimensions beyond the 4th dimension, such as the 10-dimensional string theory.

## 4. How does the 4th dimension affect our daily lives?

The 4th dimension is a crucial aspect of our daily lives, as it governs the concept of time. Our perception of time, as well as the laws of physics and the universe, are all influenced by the 4th dimension. However, we are not directly aware of its influence, as we are limited to experiencing only three dimensions.

## 5. Can we travel through the 4th dimension?

The concept of traveling through the 4th dimension is still a topic of debate among scientists. While some theories suggest the possibility of time travel through the 4th dimension, it is currently not proven or feasible with our current understanding of physics. However, advancements in scientific research and technology may lead to a better understanding and potential for travel through the 4th dimension in the future.

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