Once, humans "believe it" about the above three modes of time travel and think that time and space travel is feigningly feasible, but suddenly one day someone raised a "grandmother paradox", so the above three modes of time travel were caught in human doubts.

The grandmother paradox is also called the grandmother paradox. That is to say, a person travels through time to the time when grandmother exists and mother has not been born, and waves a knife to kill grandmother. If grandmother dies, then mother will definitely not exist. If mother does not exist, this time traveler will definitely not exist. Since she does not exist, how can she travel to the past?

Hey, this paradox sounds very reasonable at first glance, and it is difficult to refute it. Einstein and Professor Hawkingkin wanted to break their heads but did not come up with a way to refute it.

The paradox of small grandmothers once plagued mankind for many years, and to some extent destroyed the space-time travel theory established by Einstein. Alas, what's the matter?

Humans are looking forward to time and space travel, and they always want to try it. If time and space travel cannot be realized theoretically, many people will not cry to death!

The abominable grandmother paradox is a "stumbling block" that blocks human time and space travel, and many scientists are trying to overthrow it. Not to mention, scientists have come up with the magic weapon to crack the grandmother paradox, the parallel universe theory.

Einstein's time and space travel is time and space travel in an infinite universe, that is, the universe where we are "subjective". He himself never doubted that there is only one "universe" in the universe. Einstein thinks this way, and no one thinks he is wrong until now. However, in order to "break" the grandmother paradox of time and space travel, scientists have made some improvements to his "cosmview" or put forward some hypothesis.

The Big Bang theory believes that the universe is an initial point, which covers all matter in the universe today, with infinite volume, infinite density, and infinite mass. If we regard the initial point of this universe as a super super giant black hole, it is also OK. We don’t know how the initial singularity of this universe was formed and how it works, but we know that the universe centered on this singularity does not matter time, space, and everything is nothing.

Suddenly, "one day", this singularity that covers all matter in the universe exploded without knowing the reason for the magic horse.

We can vaguely imagine the scene during the Big Bang: in the dark night sky with nothingness, a very bright lightning suddenly passed through the sky. In an instant, lightning and thunder roared, the sky collapsed and the earth cracked, and all kinds of messy substances scattered out at the speed of light...

N years after the Big Bang, our current universe was formed, with N multiple stars, N multiple planets, and N multiple nebula...

So, will something interesting happen after the Big Bang?

Some people regard the Big Bang as blowing bubbles, yes, blowing bubbles. Use a bubble stick to dip a little bubble liquid, bulge your cheeks, and after a burst of puffs, there are round bubbles all over the sky, big and small, which looks very beautiful. When there are enough bubbles blown out, there will inevitably be some amazingly similar ones in the bubbles, the same volume, the same mass, and the same shape... For these bubbles with extremely high similarity, we give it a name, "parallel bubbles".

To a certain extent, blowing bubbles and the Big Bang have similarities. Blowing bubbles will blow out N multiple bubbles, but will the Big Bang also explode N multiple "small universes"?

In order to better understand, we can understand the nested small universes in the universe as "galaxy groups". However, this "galaxy group" is large enough to cover the Milky Way and the Andromeda galaxy... The human vision will never see its boundaries. And if the "star group" and "star group" are in a state of "the sound of chickens and dogs, and they will never interact with each other when they die."

When the number of small universes is large enough, astronomical numbers, thousands or billions of millions, we can draw a very interesting conclusion: there are many surprisingly similar "small universes" in the universe.

Someone will give an example. Use thousands of words in our Chinese to combine them and combine them randomly. As long as the number of combinations is enough, one can be combined to produce a book called "Dream of Red Mansions". Therefore, in the small category, the infinite number of small universes formed by the Big Bang of the Universe will definitely be similar to each other. Among them, there are many small universes that exist on our earth, including the earth, the solar system, the Milky Way, etc., but there are some differences in time, that is, different time systems. These small universes with different time systems are called parallel universes.

The parallel world only has different time systems, and other places are similar. In our small universe, history has become history and is irreversible. For example, Li Erdan's biological father Li Xinglin died, and it is impossible to resurrect him. But in another parallel universe, our history here may have just begun in their place. There, Li Xinglin is elopement with Long Xiner. Similarly, our present may also be a history in other universes. There is no Li Erdan because he has died.

If the parallel universe really exists, then there will be no "grandmother paradox" when traveling in time and space, because there are infinitely many parallel universes and infinitely many grandmothers. Even if one is killed, more will still be there.

So, is the metaphysical theory of parallel universe true or false? Does parallel universe really exist?

What do you know? Although some scientists seem to have found evidence of the existence of parallel universes by studying "cosmic microwave background radiation", they also boasted that there are one billion parallel universes in Shenma, but it is a bit out of the blue. There are not many people who believe it because there are not many people who can understand it. For example, Professor Wang Zhi does not agree with the viewpoint of parallel universes.

Erdan was half-understood, and suddenly said, "Professor Wang, after all, I didn't understand what you said. Now you give me a correct word, is time travel good? If it works, will I go wherever I want to go through time travel? Can I go wherever I want to go?"

Professor Wang Zhi laughed, "Do you really want to know?"

Erdan nodded straight, "Are you talking nonsense? Of course I want to experience it once. If a person can experience a time and space travel in his life, then this life will be worth it!"

"I can't give you the answer now because I'm confused. To be ashamed, I have studied time and space travel for so long, but I haven't figured out any of them." Professor Wang Zhi smiled bitterly, and then changed the subject, "If you want to know what the specific situation of time and space travel is, you can only experience it yourself."

"Well, where can I experience it?" Erdan.

"Lop Nur's big ears and eyes bottomless abyss."
Chapter completed!