Mountains, seas, distant stars.

All of this exists in space, just like us. Our bodies occupy a certain amount of space, and when we walk on the road, we move through the space.

But what is space? Is it even an actual physical entity?

As early as 1717, there was a debate around this issue. Today, 300 years later, the debate continues.

You might think that physicists have solved the "space" problem.

Mathematician Hermann Minkowski and physicist Albert Einstein have taught us that seeing space and time as a unified continuum can help us better understand the motion of large-scale macroscopic objects such as stars and small-scale microscopic objects such as atoms.

Still, we haven't been able to solve the question of "what is space". If all the matter in the universe were sucked out, would space still exist?

Physics in the 21st century is compatible with two very different notions of space: "relationalism" and "absoluteism".

Both views should be credited with their popularity to Caroline of Ansbach, a German-born Queen of England with a passion for philosophy.

Caroline was a keen philosopher, and in the early 18th century, she planned to pit the great philosophies of her time against each other. On the European continent at that time, philosophers were trapped in "theory-only", often on paper.

At the same time, British philosophers were developing scientific theories based on observations, a kind of "empiricism". They admired scientists like Robert Boyle and Isaac Newton.

Caroline appointed two people and asked them to exchange letters: one was the German philosopher Gottfried Leibniz, an outstanding theorist; The other was Newton's close friend, the English philosopher Samuel Clarke. The two agreed to exchange letters, which were later published as a Collected Papers in 1717.

Dull titles may not sound new, but their value is subversive. One of the central questions explored in these essays is the nature of space.

Everything? Or nothingness?

Is there space between stars? The relationist Leibniz believed that space refers to the spatial relations between things. For example, Australia is "south" of Singapore, the tree is about three meters to the left of the bush, you are standing "behind" the bush, and so on.

This means that space doesn't exist independently of what it's connected to. For Leibniz, there can be no spatial relations if objects do not exist, that is, if our universe is destroyed, then space will not exist.

On the contrary, the absolutist Clark argues that space is a ubiquitous place, a huge container that contains everything in the universe: stars, planets, and us.

It is the existence of space that makes the movement of an object from one place to another reasonable, and makes the entire material universe meaningful through space.

What's more, Clark believed that space was sacred: space was God's presence in the world.

In a way, space is God. For Clark, if our universe is destroyed, space will still be there. Just like you can't delete God, you can't delete space.

The correspondence between Leibniz and Clark ignited a wave of debate in the early 18th century. Thinkers like Newton, who were already engaged in the debate, were pulled deeper into the question.

According to Newton, space is not just a relationship between physical objects, it is an absolute entity to which everything is related.

This leads to a distinction between "relative motion" and "absolute motion", for example, the Earth moves relative to other objects, such as the Sun, but it also moves absolutely relative to space.

Other great philosophers, such as Immanuel Kant, believed that space was only a concept that humans use to understand the world, not a real entity. It was not only philosophers and physicists who could express their views on space, but everyone from wholesalers to tenant farmers had the right to express their opinions.

People are particularly agitated about Clark's view that space is God, and people ask if this means that we are always moving around the agreement. So God not only sees everything, but He is everywhere? They are also worried about some "big things", such as the whale occupies more space than a clergyman, so is it true that the whale is more sacred than the clergy? The mountains are so big, and are they like God?

Bertrand Russell, the great philosopher of the 20th century, once said that we should not choose to worship based on size.

He wrote: "Sir Newton was much smaller than the hippopotamus, but we do not think that he was worth less than the beast." But some thinkers in the 18th century may not have agreed with Russell's words, because they were genuinely concerned about whether the hippopotamus should be worshipped more than Newton.

Today, the part of the debate that has to do with God has all but disappeared. However, some contemporary philosophers have argued that, stripped of the part related to religion, current theories of physics actually support Clark's view that space-time is a giant vessel around which all of us travel.

There are also modern philosophers who believe that the best theories of physics can accommodate these two different views, and there are other reasons to believe that Leibniz's theory is correct. If physics is really compatible with absolutism or relationalism, then perhaps we should take relationalism as a simpler theory? After all, why do we have to assume a large, container-like entity?

As a historian of space and time, I am fascinated by how this debate, which began 300 years ago, evolves, and how things that began 300 years ago unfold and grow.

Obviously, although the letter papers of Leibniz and Clark are not well known outside of philosophy, the debate they began continues with half the merit of Caroline of Ansbach.

So what does space have to do with dimension?

"Dimension" is a measure in which three-dimensional spatial coordinates, plus time, space-time and space are interconnected to form a four-dimensional space.

Scientists' theories suggest that the entire universe is 11 dimensions, but human understanding can only be understood in 3 dimensions.

To use an analogy: if an intelligent creature lives around us but can only understand two dimensions, is it in two dimensions? But around them, we clearly think that it is a three-dimensional space, both sides are intelligent beings, who is right and who is wrong?

Zero-dimensional: There is no length, width or height, and a simple point, that is, the singularity [1], and the black hole is also a singularity.

One-dimensional: There is only length, i.e., lines.

Two-dimensional: Flat world has only length and width, i.e., faces.

Three-dimensional: length, width, height, three-dimensional world The three-dimensional space of the world that we perceive and see with the naked eye is the space where the position of the point is determined by three coordinates. The objectively existing real space is three-dimensional space, with three measures: length, width, and height. The concept of multi-dimensional space introduced in mathematics, physics and other disciplines is a scientific abstraction based on three-dimensional space, which is also called four-dimensional space-time.

Four-dimensional: A Concept of Space-Time Most of the "four-dimensional space" mentioned in everyday life refers to the concept of "four-dimensional space-time" mentioned by Albert Einstein in his "General Theory of Relativity" and "Special Theory of Relativity".

Our universe is made up of time and space. The relationship between time and space is that a time axis is added to the structure of space compared with the three axes of length, width and height of ordinary three-dimensional space, and this time axis is an imaginary value axis.

According to Albert Einstein's theory of relativity, the three-dimensional space we face in our lives plus time constitutes the so-called four-dimensional space.

Five-dimensional: In this space, time may exist in a concrete linear way

String theory predicts that there are a total of eleven dimensions in space, and there are about 26 spaces in addition to special spaces such as antimatter space, but we humans have only explored five dimensions, and the other six dimensions are called hyperspace.

The zero dimension is a point, the one dimension is a line, the second dimension is a surface, the third dimension is a static space, and the fourth dimension is a dynamic space.

The parameters that we have to change in physics to describe a changing event. This parameter is called a dimension. A few parameters are just a few dimensions. For example, to describe the position of a "door", you only need angles, so it's one-dimensional, not two-dimensional.

The jog moves into a line, the line moves into a surface, and the surface moves into a body

A number of points form a line, a number of lines form a surface, and a number of faces form a body

Because the human eye can only see three dimensions, it is difficult to interpret more than three dimensions. Just as a person with normal intelligence and a congenital absence of one eye or ear, it is difficult for him to understand distance, and he is likely to think that the world is two-dimensional.

To put it simply: the N-dimension is the space formed by the perpendicular pairs of N straight lines.

Because, human beings can only understand 3 dimensions, the later dimensions can be constructed by mathematical theories, but it is difficult to understand carefully. In quantum mechanics, the membrane theory is still being established, which holds that the universe is 11 dimensions.

The Philosophy of the Universe is a view of the number of dimensions in the universe

In reality, the universe is five-dimensional:

Time is one-dimensional, space is three-dimensional, matter is one-dimensional. A total of five dimensions.

In the spirit, it can be infinitely dimensional, because the spirit is remembering the things of the past, where it can be imaginative!

We human beings have been constantly exploring the mysteries of the universe, science has made us understand a lot, we know a lot, and we have also explored many things from science that we have never understood.

And our understanding of the universe has been constantly deepening, in the future, where we human beings should go in the universe, it will be difficult for us to meet.

In the process of exploration, we learned that human beings live in a three-dimensional universe. The universe dimension starts from 1 dimension, so what is the 0 dimension space? I've read the long knowledge!

It is understood that the latitude of space was proposed by scientists on the basis of proposing parallel universes, and the current theory is that the dimensions of the entire universe are 11 dimensions, and we are in a three-dimensional space. Dimensions start from 1, so is there a space in the universe with 0 dimensions? The number 0 generally means that there is nothing, empty. But it is sometimes extended to mean "to start", that is, to start from scratch.

Scientists say that a 0-dimensional space is a space without any dimensions, it has no size, there is no data to build, so it is also represented by a point, and this point is the singularity. The definition of it in physics is contradictory, it is a point that exists and does not exist, at which time and space have infinite curvature, and 0-dimensional space is also regarded as a singularity that can end time and space.

Albert Einstein also mentioned in the general theory of relativity that under certain circumstances, the singularity must exist, especially since the universe must start with a singularity, but it is a point without any size, that is, a point that does not actually exist. I believe that everyone has been dizzy here, in fact, this 0 is the beginning of all things, but there is nothing, scientists often use singularity to describe the center of the black hole.

Because a black hole is also a dense and gravitational entity, the center of the black hole will be the densest place. The centripetal force is extremely attractive and is finally compressed into a point, which is also known as the cardinal point. Seeing this, you should understand, in fact, there are a total of 11 dimensions in the universe, and we in the third dimension have no way to understand the form of life in a higher dimension than us, just like the life in the two-dimensional space cannot understand us.