she xiang of spatial interface 1

Is there another article you are reading exactly the same as this article? That guy is not yourself, but lives on a planet with cloudy mountains, endless fields, noisy cities, and eight other planets rotating around a star, also known as "Earth"? His or her life experience is the same as yours every second. However, maybe she is about to put down this article and you are going to read it.

This idea of "spent" sounds strange and unbelievable, but it seems that we have to accept it because it has been supported by the results of various astronomical observations. Today's most popular and simplest cosmic model points out that there is a galaxy about 10^(10^28) meters away from us that is the same as our Milky Way, and there is a similar you. Although this distance is beyond people's imagination, it does not affect the authenticity of your "sup" existence. The idea originated from a simple "natural possibility" rather than the assumption of modern physics: the universe is infinite in size (or at least large enough) and evenly distributed matter, as astronomical observations have pointed out. In this case, according to the laws of statistics, it can be concluded that all events (no matter how similar or identical) will occur countless times: there will be countless planets that give birth to human beings, and there will be people who touch the same as you - the same appearance, name, memory and even the same movements and choices as you touch - There is more than one such person, to be precise, there are infinitely many.

The latest cosmological observations show that the concept of parallel universe is not a metaphor. Space seems to be infinite. If so, everything that may happen is bound to happen, no matter how ridiculous it is. There is a universe much farther than our astronomical observation. Astronomers even calculate their average distance from the earth.

You may never see your "shadows". THE FARST DISTANCE YOU CAN OBSERV IS THE FARST DISTANCE THAT LIGHT HAS travelED SINCE THE ANG: ABOUT 14 BILLION LIGHT YEARS, THAT IS, 4X10^26 METERS - THE Sphere WITH A RADIUS DEFINES THE SIZE OF OUR OBSERVABLE vision, OR SIMPLY, THE SIZE OF THE UNIVERSE, ALSO KNOWN AS THE HARB VOLUME. Similarly, the other universe you are in is also a sphere of the same size. The above is the most intuitive explanation of the parallel universe. Each universe is a small part of the larger "multiverse".

People may think that this is just a metaphysical way to define the universe. However, the difference between physics and metaphysics is whether the theory can be tested experimentally, not whether it looks strange or contains something imperceptible. Over the years, the frontier of physics has been expanding, absorbing and integrating many abstract (even once metaphysical) concepts, such as spherical earth, invisible electromagnetic fields, slowing down the flow of time at high speeds, quantum overlap, space curvature, black holes, etc. In recent years, the concept of "multiverse" has also been added to the above list, which is combined with some previous tested theories, such as relativity and quantum mechanics, and has reached at least one basic standard of empirical scientific theory: making predictions. Of course, the assertion may also be wrong. Scientists have so far discussed as many as four types of independent parallel universes. The key now is not whether multiple universes exist or not, but how many levels they have.

First Level: Beyond the Vision

All parallel universes form the first layer of multiple universes. --This is the least controversial layer. Everyone accepts the fact that although we can't see the other self at this moment, it can be observed in another place or simply waiting in place for a long time. It's similar to observing ships coming from above sea level - observing objects outside the horizon. With the flight of light, the observable radius of the universe expands by one light year every year, so you just need to sit there and wait and see. Of course, you probably can't wait for another universe's light to come here, but theoretically, if the theory of cosmic expansion is tenable, your descendants may see them with super telescopes.

How about the concept of the first layer of multiple universe sounds ordinary? Isn't space infinite? Who can imagine a sign somewhere with the book "This is the end of the space, be careful of the ditch below"? If so, everyone will instinctively doubt: what is the "outside" at the end? In fact, Einstein's theory of gravity field turned our intuition into a problem. Space may not be infinite, as long as it has some degree of curvature or is not our intuitive topology (i.e. interconnected structures).

A spherical, frying circle-shaped or horn-shaped universe may be limited in size but without boundaries. Observations of cosmic microwave* radiation can be used to determine these assumptions. [ See another article "Is the universe limited?" byJean-PierreLuminet, GlenD.StarkmanandJeffreyR.Weeks;ScientificAmerican,April1999] However, the observations so far seem to be contradictory. They. The model of the endless universe is in line with the observation data and has strong restrictions.

Another possibility is that space itself is infinite, but all matter is limited to a limited area around us - the once popular "island universe" model. The difference of this model is that the material distribution will show a fractal pattern on a large scale, and it will continue to dissipate. In this case, almost every universe in the first multiverse will eventually become empty and fall into death. However, recent observations on the three-dimensional galactic distribution and microwave* have pointed out that the organization of matter shows some vague uniformity on a large scale, and no clear details can be observed on a scale greater than 10^24 meters. Assuming that this pattern continues, we can observe that the space outside the universe will also be full of planets, stars and galaxies.

There is data to support the theory that space extends beyond the observable universe. The WMAP satellite recently measured the fluctuation of microwave radiation (left). The strongest amplitude exceeds 0.5, implying that the space is very large and may even be infinite (middle picture). In addition, WMAP and 2dF galaxy redshift detectors found that matter is evenly distributed in space at a very large scale

Observers living in different parallel universes in the first layer of multiple universes will perceive the same physical laws as us, but the initial conditions are different. According to the current theory, matter is thrown at a certain randomity in the early moment of the Big Bang. This process contains all the possibilities of material distribution, and each possibility is not 0. Cosmologists assume that our universe, which has an approximate uniform distribution of matter and an initial fluctuation state (one of 100,000 possibilities), is a fairly typical (at least typical in all parallel universes that produce observers). Then the person closest to you will be 10^(10^28) meters away, and there will be an area with a radius of 100 light years only 10^(10^92) meters away. Everything in it is no different from the space we live in, that is to say, what will happen in our world in the next 100 years. Everything will be completely reproduced in this area; and at least 10^(10^118) meters away will the area increase to the size of Hubble, in other words, there will be a universe exactly like ours.

The above estimate is extremely conservative. It only enumes all the quantum states of a space with a temperature below 10^8 and a Hubble volume. One of the calculation steps is this: how many protons can be accommodated in the Hubble volume space at that temperature? The answer is 10^118. Each proton may or may not exist, that is, a total of 2^(10^118) possible states. Now you only need a box that can hold 2^(10^118) Hubble space to use up all possibilities. If the box is larger -- such as a box with a side length of 10^(10^118) -- according to the principle of the drawer, the arrangement of protons will inevitably repeat. Of course, the universe is not only protons, but also two quantum states, but the total amount of information that the universe can hold can be estimated in a similar way.

The average distance of another universe like our universe

The closest "spitch" to you may not be as far as the theoretical calculation, maybe much closer. Because the organization of matter is also restricted by other physical laws. Given some laws such as the formation process of planets and chemical equations, astronomers suspect that there are at least 10^20 inhabited planets in our Hubble volume alone; some of them may be very similar to the Earth.

The framework of the first layer of multiverse is usually used to evaluate the theory of modern cosmology, although the process is rarely clearly expressed. For example, examine how our cosmologists try to get a geometric map of the universe of "spherical space" through microwave*. With the different radius of curvature of space, the size of those "hot regions" and "cold regions" on the cosmic microwave* map will show certain characteristics; and the observed areas indicate that the curvature is too small to form a spherical closed space. However, it is very important to maintain statistical strictness. The average size of these areas in each Hubble space is completely random. Therefore, it is possible that the universe is fooling us - it is not that the spatial curvature is not enough to form a closed sphere that makes the observed area smaller, but coincidentally the average area of our universe is naturally smaller than others. So when cosmologists vow to guarantee the 99.9% credibility of their spherical space model, their real meaning is that our universe is so incompatible that one of the 1,000 Hubble volumes will produce something like that.

The point of this lesson is that even if we can't observe other universes, the theory of multiple universes can still be verified in practice. The key is to predict the commonality of various parallel universes in the first layer of multiple universes and point out their probability distribution - what mathematicians call "metrics". Our universe should be one of the most likely universes. Otherwise -- we unfortunately live in an unlikely universe -- then the previous hypothesis will be in big trouble. As we will discuss next, how to solve this quantitative problem will become quite challenging