Is the universe really boundless, is the universe boundless?

Einstein's model of the universe states that the universe is a finite and unbounded space. Do you understand what finite and unbounded means?

If we are creatures in 2D space, then on a 3D sphere, we can't see the end of how we go, but the area of the sphere is limited!

Then we are now living beings in a 3-dimensional space, but the universe is 4-dimensional (originally 26 dimensions, and the remaining 22 dimensions have collapsed to the point where they cannot be observed), so no matter how big the universe is, although it is limited, we can't see an end.

Yes, but the universe is not one"stuff"It contains everything.

If it's boundless, you can't think of it, but that doesn't prevent it from being boundless.

If there is a source, there is a non-source outside the source.

The universe is boundless.

No one can calculate the boundaries of the universe

No one has an answer to this question. When I was a child, I often thought about this kind of problem, but it's useless to think about it, so let's watch more science fiction when I have time.

In Einstein's words, it is "boundless".

The universe is infinitely large" High School Geography Book 1 Page 1!!

Hello. For you: the universe is boundless.

For the time being, the universe is boundless. The so-called bounded universe is only the part that human beings can estimate, and that part is already terrifyingly large. To use an analogy, there is a Xinjiang ant who has crawled all his life and has never climbed out of Xinjiang, so he said that Xinqi Nianjiang is boundless.

Later, his descendants continued to climb, and finally climbed out of Xinjiang and came to Gansu, so the science of ants reached a new peak, it turned out that Xinjiang has a border, and there is Gansu. Is Gansu the end of the world? So countless generations of ants continued their scientific practice, continued to climb, and finally crossed China, came to the east of the motherland and trapped on the seaside, and finally couldn't climb anymore, looking at the boundless sea, the ants sighed, the world turned out to be really boundless.

In fact, on the other side of the sea, we know that there are still rough books, and many ants do not know things. People in the universe are like ants on the earth, there is still a long way to go to understand the whole world, maybe billions of years later, the sun will be big**, human beings will be extinct, and human beings will not be able to understand the entire universe. If the universe has a limit, but for the destroyed human race, this limit is actually boundless, and you don't have the time or ability to know the whole limit.