How big is the universe!! Is it really endless???

Whether the universe is finite or not, and the outcome of the universe, is determined by its average density.

There is a critical density = 10 to the power -29 (grams of cubic centimeters).

If the average density of the universe is less than it, then the universe is "open", infinite, and boundaryless. And the universe is loose, and gravity is not enough to pull the expanding universe back – the universe will continue to expand.

If the average density of the universe is greater than the critical density, then the universe is "closed" and finite. And gravity can cause the universe to re-contract on a certain day, forming a cycle.

However, it is now difficult to determine the average density of the universe, and the conclusions of the two measurement methods are that one is larger than the average density and the other is smaller.

But beware, even if the universe is finite, you can't find its boundaries. Because it is a "three-dimensional sphere". To make an analogy:

A two-dimensional sphere, such as a leather ball, an ant climbs on it, and the ant finds that the area of the ball is limited, but it can't find the boundary of this finite area in **. It will never touch a boundary to block it, but the area is really limited - because the sphere is closed! It's the same with our three-dimensional universe, if we start from one point and go all the way forward, we will come back to the starting point from behind – just like an ant crawling around a ball.

Limited and unbounded.

The universe is as big as the heart.

It's hard to say, it must be very big.

Humanity has only explored one ten-thousandth of the universe.

Big, big!! It's too big! Very big, very big, quite big!!

Before the universe is space, before space is the universe, and the universe is completing the transformation of energy, matter, and time.

We modern people don't understand what the universe really is, and we just treat it as a space with nothing for the time being.

2 million years ago, a big **, I can't imagine it.

There is no time and no space, it is the origin of all coordinates, and it is also an imaginary number. I don't know.

The universe originated 15 billion years ago with a great **.

Now there is a theory called big **, the universe began by an infinitely small volume, infinitely large density, singularity, and then the big **, forming the current universe, Hawking proposed a model is that the universe is constantly expanding, just like a balloon (under the action of dark matter), when the force of dark matter disappears, the universe will collapse into a singularity under the action of gravity. Who doesn't hit it by hand?

I believe that the vast universe should be boundless, boundless, beginningless, and endless. The universe itself already contains everything, and there is no such thing as an internal and external and marginal problem. No matter which direction you go in, it should be endless and endless, and it cannot be blocked by anything, which is the infinite cosmic space.

I think it's absurd to think that the universe is boundary, and if the universe is boundary, what is that margin? Is there no beyond the margins? And since there are edges means that there will be edges, this question is actually difficult to justify, how can people who say that the universe has an end explain it?

The only thing that makes sense is that the universe is infinite and infinite! It can be said that the infinite universe is indeed unimaginable to us, and it has long been beyond the scope of human cognition! But this is the infinite universe, a mystery that humanity will never be able to solve!

Yes. People don't know what it is, though.

The current radius of the universe is about 46.5 billion light-years, with a diameter of 93 billion light-years. However, 93 billion light-years is only the diameter of the universe that we can observe, and since the universe is expanding faster than the speed of light, we cannot know how big the universe really is if we only observe the universe from Earth, which is still an unsolved mystery.

How big is the universe? Star Awareness Project

Dictionary explanation.

宇宙 (yǔ zhòu),"The four directions are said to be the universe, and the universe is said to be the sky throughout the ages. "——Xinhua Dictionary

In the pluralistic Chinese language, "yu" represents the upper and lower four directions, that is, all space, and "zhou" represents the past and present, that is, all time, yu: infinite space, and zhou: infinite time. So the word "universe" has the meaning of "all time and space".

Once the universe was formed, it was in constant motion. Scientists have discovered that the universe is expanding, and the distance between stars is increasing.

The universe has a beginning, no end, no boundary, no birth and destruction, only the end and beginning of each stage, and our current universe was formed about 20 billion years ago. In an incomparably spectacular big **, this stage of the universe begins! The latest research shows that the big ** is conceived in a black hole, which presses all matter, including photons, to a point where even electrons, neutrons, protons, etc. no longer exist (what matter is smaller than electrons?).

Contemporary technology cannot explain it, tentatively called quarks), at this time, there is a higher level of ** than the nuclear fusion change, and the range of this ** affects at least billions of light years, and a new era of the universe is born. Title]: Universe.

There is a beginning, there is no end, there is no boundary, you can think for yourself.

I think it's definitely finite, like an ant on Earth, who doesn't know how big the Earth is, only infinitely big, but the Earth is finite.

It took a billion years to run so far at the same speed ...

There are theories upstairs that support modern science (just as easily overturned as the sun revolves around the earth or the earth is flat), and I would like to express a different opinion, hoping that you can carefully judge by your own feelings, how big is the universe? You can develop your imagination a little more, and our country lacks this.

Now the brick home. The professor depicts the universe very big and very big, observing it with a radio telescope, I want to laugh, the level of technology of aliens, put a multi-angular mirror on your telescope, what you see is always an endless refraction of the mirror, a few galaxies are enough...

I think of the universe as a very, very small walnut, and there are many, many walnuts out there, and a lot of the universe grows on or is attached to a cylinder.

Our universe is very small, it has not yet matured, and when our universe matures, it can fall down Nothing is eternal, including planets, galaxies, to look small and big, you reach out and grab something, this, this is what a certain universe looks like, you have to believe your feelings.

The universe is as big as the heart.

A theory without evidence is a fart.

No one can give this answer.

How big is the universe? Star Awareness Project

It is impossible to know how big the real universe is, because the universe is expanding faster than light, and people cannot see the deepest part of the universe at all. We can only talk about how big the observed universe is.

The universe appeared 13.7 billion years ago, and the celestial bodies in the universe were created in the big **, that is to say, the earliest celestial bodies were born 13.7 billion years ago. According to the principle that the universe is similar on a large scale, the Earth is theoretically able to receive light from these earliest celestial bodies, so the earliest celestial bodies that can be seen on Earth were born 13.7 billion years ago. The universe has always expanded, and the rapid expansion of space has dramatically increased the distance, and by the time the light of the farthest celestial bodies reaches the Earth, they have receded to 47 billion light-years away.

In this way, the farthest object that can be observed by humans is about 47 billion light-years from the Earth, and the scale of the observed universe is about 94 billion light-years.

Officially, the diameter of our universe is 13 billion light-years.

First, let's realize that the universe is very large, and the size of the universe that we observe (expressed in Hubble radius) is based on measuring the distance of the farthest celestial body from us.

In this way, the universe should be understood as the space that we can see. I find it more practical that way. Besides, we don't know anything beyond the Hubble radius, and we can only guess at best.

If you mean to include outside the Hubble radius, then Einstein probably didn't know either.

The universe is big and has no outside, and small and has no inside.

If the mind is big, the universe will be big.

The universe is as big as the heart.

How big is the universe? Star Awareness Project