At different times, people have different perceptions of the world in which they live, for example, our view of the earth now must be very different from that of thousands of years ago. Although we have not yet fully understood everything about the earth, we at least know what kind of existence the earth is in this universe, and we know the smallness of human beings.
As for what kind of universe we will see in the future, we obviously have no way to predict it now. The only thing we can be sure of is that humanity will inevitably continue to explore this vast universe in the future, supplementing the vast amount of knowledge that we still lack now, and striving to make our civilization even greater.
One question that has been bothering people all along is how big is this universe? After the development of modern science, our observation technology for the universe has also greatly improved, and many optical observation devices have emerged. In modern times, optical observation equipment can no longer fully meet our needs for space exploration.
We have also developed many instruments to detect the "invisible" cosmic matter, such as radio telescopes and so on. With the cooperation of various tools, what new understanding do we have about the space we are in, and what conclusions can we draw from it? Let's take a look.
<h1 class="pgc-h-arrow-right" data-track="11" > the origin of the universe</h1>
Since we want to know what more matter looks like in the universe, we must first know how the universe was born, that is, the origin of this material universe. It is now known that our universe was not the work of the "Creator," as the myth suggests, but that it originated from a big bang tens of billions of years ago.
In an endless vacuum, all matter is concentrated in that one "singularity", and after the Big Bang, this matter quickly gushes out and expands outward, and our universe is born. To this day, our universe is still in a state of expanding state of the Big Bang.
Obviously, people have no way of knowing what the big bang was like at the time of the big bang, and can only speculate on what the young universe experienced through some clues that are still in the space of the universe.
For example, our optical observation equipment has received light from 13.8 billion years ago, so does this mean that the place where these lights came is the end of the universe in which we live? Before thinking about this question, we need to clarify one thing, that is, how big is our universe, and whether the universe we know is the scope of its own existence.
<h1 class="pgc-h-arrow-right" data-track="23" > how big is our universe? </h1>
Although what we can see is light from 13.8 billion years ago, that doesn't mean our universe only has a radius of 13.8 billion light-years. There are two main reasons for this, one is that our universe has been expanding since the Big Bang, the time it takes for light to reach where we are and is received by human observation devices, and the matter itself is constantly moving away from each other as the universe expands.
According to the researchers' calculations of the rate of expansion of the universe, these galaxies that emitted light 13.8 billion years ago are far away, about 46.5 billion light-years away.
Since this is the oldest light we have observed of the knowable universe, this means that our knowable universe has a radius of about 46.5 billion light-years, or about 93 billion light-years in diameter. Simply put, even at the speed of light, it would take 46.5 billion years to reach the edge of the known universe.
So, is this the true size of our universe? In fact, there is a second influencing factor, that is, we may not be at the "center" of the known universe, so we can't be sure whether this light really comes from the edge of the universe. Therefore, we cannot be sure that the size of the real universe is really 93 billion light-years.
The "agnostic universe" is connected to the edges of the universe that we can observe, and we will never be able to reach beyond this if we follow the usual speed and manner, because the universe is already expanding faster than the speed of light. That is to say, we can know that the universe is expanding, but we can never see what else is beyond that.
Perhaps the unknown universe is a world that is larger than the known universe, but there are still a series of alien civilizations. But because of the shackles of the speed of light, we will never be able to actually observe each other. Why is our speed limit the speed of light? Do we have any faster speeds above the speed of light?
<h1 class="pgc-h-arrow-right" data-track="41" > human speed</h1>
Since realizing the shackles of earth's gravity, human beings have been looking for ways to get rid of the shackles and go to the universe, and realized that the key to the problem is speed.
Only when we reach the "first cosmic velocity", that is, 7.9 kilometers per second, can we rush out of the atmosphere and become objects orbiting the earth, and if our speed is less than this value, then we will be bound by the gravitational pull of the earth and fall in the direction of the ground. And if we exceed the "second cosmic velocity," the object will leave the Earth's orbit and enter the gravitational orbit of the sun, becoming an "artificial planet."
And if we succeed in building a spacecraft that reaches 16.7 kilometers per second, which is the "third cosmic velocity," then we can leave the shackles of the sun's gravity and go to more distant space.
The third cosmic speed is the limit that human beings can currently reach, but according to the researchers' calculations, there should be three stages of speed above that, the fastest of which is the speed of light, which is also the highest speed that matter can achieve in the conventional seeing space without distortion, which is about 300,000 kilometers per second, which is determined by special relativity, so under normal circumstances, there will be no speed exceeding the speed of light, and humans cannot do it.
<h1 class="pgc-h-arrow-right" What is the end of the universe > data-track="54"? </h1>
Since we can't see the world outside the known universe with our own eyes, can we calculate what is at the true end of the universe? Answering this question requires a premise, and that is, is there an end to our universe? If it is a existence with no end, then what about "things with an end"?
Despite our limited observational conditions, researchers have figured out a way to measure the size of the universe, and that is curvature. The curvature of any finite space cannot be 0, and only an infinite space can be absolutely flat, which is the theoretical premise of curvature measurement.
After measurement, the researchers found that the curvature of the universe is close to 0, that is, the universe is inherently infinite, and there is no end to nature. In fact, of the three models of the universe given by the researchers, only the spherical closed universe is finite. But even for a finite universe, there is no such thing as an "end."
Therefore, according to the information we have now, the universe is an infinite space of matter that is constantly expanding, and matter is moving away from each other. After the energy between matter is thinned to a certain extent, the universe will enter a "hot silence" state and begin to collapse, eventually returning to its original state.
<h1 class="pgc-h-arrow-right" data-track="68" > how do we get past the speed of light? </h1>
Since the speed of light itself is already the limit of speed, is it impossible for us to break it? But we can change our thinking, after all, the purpose of speeding up is to go farther in a shorter period of time, which means that our results are far more important than the process.
Since the fastest speed of light presupposes normal space, can we use the device to directly traverse space? People have now come up with an idea for this device, which is a warp engine. This engine can start directly from space itself, directly exceeding the actual travel speed of light, reaching several times or even dozens of times the speed of light.
Although this engine only exists in some science fiction works at present, it does not mean that it really will not exist in the future. Because from a purely theoretical point of view, there is nothing wrong with the warp engine, but it will take time to implement this technology. When this technology matures, we can really complete the "interstellar travel" like in the TV series.
By that time, what kind of world will humanity discover beyond the universe that it can see now? This is still unknown to us, but it is very worth looking forward to, because human exploration is endless, and we are constantly curious about everything in the universe.
<h1 class="pgc-h-arrow-right" data-track="81" > conclusion</h1>
Through this research, we can also know that our series of explorations of the universe are not "useless", but involve more practical aspects of the future world, such as the problem of our interstellar crossing. For humans, the earth's resources are limited, but it is obvious that human beings cannot give up sustainable development.
In the face of the earth's increasingly serious problems, we can only constantly find new resources or other homes. But for humans now, the lack of technology has severely limited our development, and we can't even reach other planets in the solar system in a short period of time.
If we can one day travel freely in our galaxy and even in the known universe, then many of the problems that plague us now are no longer problems, and the human race can build its own civilization on more celestial bodies, then it can be considered "advanced" in the whole universe.
In comparison, human beings are still in the stage of "passive acceptance", and they are still far from the development goals we envision. But the good news is that researchers have not stopped their struggles, and we hope to learn more about the mysteries of the universe in the future, and continue to take our own steps towards the vast space.