Center of the Universe
Do you know where is the center of the universe?
Humans have long thought of themselves as the center of the Universe: how can we not imagine it looking at the night sky, with these stars in all directions? But are we really? If not, where is the center of the Universe?
The Universe has no center, simply because it has no edge. In a finite universe, space is curved in such a way that if you could travel billions of light years in a straight line, you would eventually come back to where you started. It is also possible that our Universe is infinite. In both cases, the groups of galaxies fill it completely and move away from each other at all points.
If our Universe is finite or infinite
If our Universe is finite, one way to think about it is to imagine a two-dimensional ant living on the surface of a perfectly spherical balloon. From the ant’s point of view, there is no center on the surface of the sphere, nor an edge. If you inflate the balloon, the ant will see its two-dimensional universe expand. Draw dots on the surface, and they will move away from each other – just like the galaxies in our real universe. For the ant in this two-dimensional universe, any third dimension that extends perpendicular to the surface of the balloon – toward the center of the balloon – has no physical significance. “She knows she can go forward and back, she can go left and right,” says Barbara Ryden, an astrophysicist at Ohio University. “But he has no concept of high and low.”
One of the presently unanswered questions about the universe is whether it is infinite or finite in extent. For intuition, it can be understood that a finite universe has a finite volume that, for example, could be in theory filled up with a finite amount of material, while an infinite universe is unbounded and no numerical volume could possibly fill it. Mathematically, the question of whether the universe is infinite or finite is referred to as boundedness. An infinite universe (unbounded metric space) means that there are points arbitrarily far apart: for any distance d, there are points that are of a distance at least d apart. A finite universe is a bounded metric space, where there is some distance d such that all points are within distance d of each other. The smallest such d is called the diameter of the universe, in which case the universe has a well-defined “volume” or “scale.”
Our Universe is sort of a 3D version of the ant’s 2D balloon. But the analogy of the balloon, with its limited surface, here represents a finite universe. To this day, we do not know if our Universe is finished or not. Limited by how far light has traveled since the Big Bang, observations by cosmologists offer only a limited glimpse of the cosmos, but the entire Universe could be infinite. If so, then you can replace the balloon with a flat rubber sheet that expands forever. If you want to think of a 3D universe, imagine a loaf of raisin bread that keeps expanding. Raisins, in this case, represent galaxies moving away from each other. If the Universe is infinite, there is no center either. Remember that the Universe is not part of a space: it includes everything that exists. So there can be no border, and therefore there is no “outside” to the Universe.
Whether the Universe is flat or curved depends on the total amount of mass and energy in the cosmos. So far, theoretical ideas and observations – such as those of cosmic diffuse background radiation, the Big Bang afterglow – point to a remarkably flat universe. But cosmologists are still not sure whether the universe is flat or the curvature is so small that the universe appears perfectly flat to us – in the same way we might imagine the Earth flat from its surface.
The question we might then ask ourselves is: where did the Big Bang take place?
The answer is: everywhere. If we assume that the Universe is expanding in all directions and that it began in the titanic explosion of an ultra dense atom 13.7 billion years ago, we could then, intuitively, be say that we just need to take a telescope to scan the sky for the point in space where the explosion took place. But again, the Universe is not part of a space, it “is” space “. 13.7 billion years ago, a unit of space was simply much smaller than it is today, and all matter was contained within.
If the Univers does have a center?
And if the Universe does have a center, it can be anywhere; the part of the Universe that is accessible to us for observation is insufficient to reveal this information to us. To consider this hypothesis, we would have to detect a consequent anisotropy in the temperatures, the densities of matter or the distributions of galaxies. But so far, on large scales, the Universe seems to be the same in all directions. Thus, any observer can theoretically be the center of the Universe.
The center of the Universe is a concept that lacks a coherent definition in modern astronomy; according to standard cosmological theories on the shape of the universe, it has no center.
There is no specific area from which the Universe expanded under the impulse of the Big Bang, only a time from which this expansion began, approximately 13.8 billion years.
The Big Bang is therefore an event affecting the entire observable Universe at a given time. This is why to observe great distances in all directions means to observe the past. And so it is for this reason that, no matter the direction, the Universe has uniform properties.
Why is the universe infinite?
Relativistic cosmological models identify the universe with space, precisely, with a more general physical and geometric entity, space-time-matter. So, the universe, whether finite or infinite, cannot inflate into anything, for there is no space outside of itself!
The Subjectivity of the Center
When it comes to the Universe, the idea of a definitive center becomes a matter of perspective. From a cosmological standpoint, the Universe is vast and ever-expanding, without a discernible central point. However, different belief systems, cultures, and mythologies have their own interpretations of a central point that holds spiritual, religious, or symbolic importance.
Religious and Mythological Perspectives
In various religions and mythologies, the concept of a Center of the Universe often represents a sacred or divine location. For example, in Hindu cosmology, Mount Meru is considered the cosmic axis and the center of the Universe. In Norse mythology, Asgard, the realm of the gods, is believed to be located at the center of the Universe. These perspectives highlight the symbolic significance of a central point in spiritual and mythological narratives.
From a scientific standpoint, the idea of a singular Center of the Universe is not applicable. The Universe is constantly expanding in all directions, making it difficult to identify a specific point as its center. The Big Bang theory, which describes the origin of the Universe, suggests that every point in space was once compressed into an infinitesimally small singularity. Therefore, there is no preferred or central location in the vast expanse of the Universe.
The Observable Universe
In cosmology, scientists often refer to the concept of the Observable Universe. This refers to the portion of the Universe that is visible to us, given the limitations of light speed and the age of the Universe. The observable part is centered on the observer, making it appear as if they are at the center. However, this is a perspective based on our vantage point rather than an actual center of the Universe.
The idea of a Center of the Universe is a complex and multifaceted concept. While different cultures and belief systems may assign symbolic or spiritual significance to specific locations, from a scientific perspective, the Universe lacks a singular identifiable center. The vastness and ever-expanding nature of the Universe make it challenging to pinpoint a central point. However, exploring the different perspectives and interpretations surrounding the Center of the Universe provides insights into the diverse ways humans perceive and understand the cosmos.
Note: The existence of a Center of the Universe is a topic of philosophical and scientific debate. The information provided in this article reflects current scientific understanding and cultural interpretations but may not encompass all viewpoints.
Sources: Live Science
Photo credit: Pixabay