BEIJING, Dec. 9 ( Xinhua) — According tomedia reports, the shape of the universe is one of the most important problems in cosmology, with far-reaching implications, and can even reveal the ultimate fate of the universe. Astronomers have been measuring the universe as a geometric plane for decades, but a recent cosmic study suggests that the universe is actually more likely to be curved. However, the problem is not just a simple measurement.
We all know that the earth’s surface is curved, so the geometry you learn in high school doesn’t always apply. For example, parallel lines do not always remain parallel on Earth: longitude lines intersect at the north and north poles, which is not possible on a plane. If you connect three cities on Earth with a triangle, you’ll find that the sum of the inner corners of the triangle is more than 180 degrees, which is, yes, the difference between the sphere and the plane.
Astronomers are very interested in the extreme curvature of the universe: on the most ambitious scales, how do parallel lines and triangles behave? On the other hand, this problem is important because the shape of the universe is closely related to its ultimate destiny. We use Einstein’s general theory of relativity to understand the universe, which states that the contents of space-time affect its shape, and shape determines how content moves.
The geometrically flat universe will continue to expand, and the “closed” universe will eventually shrink, leading to a reversal of the Big Bang, also known as the Big Crunch.
Look for the first light
To determine the geometry of space-time, we need to look at a variety of distant light sources and determine whether the light emitted by these light sources has deviated significantly in the path. For billions of years, the beam should remain in a straight line so that we can “smooth” the tiny bumps and swings caused by galaxies and black holes with distant probes, and observe the real, potential geometry of the universe.
Let’s take a look at the cosmic microwave background ( microwave background , or CMB for short ) , which is “the oldest light in our universe” and is full of the entire universe , leaving behind when the universe was still in its infancy (only 380,000 years old). For the past 13.8 billion years, these lights have been “flying” toward us, so you can determine whether the universe is flat by studying the characteristics of the cosmic microwave background.
Planck is a collaboration between NASA and the European Space Agency (ESA) with the goal of obtaining anaesis across the sky of cosmic microwave background radiation at unprecedented lys. The Planck satellite did a good job of measuring the cosmic microwave background to the highest level, with the latest data to be released in 2018.
If you analyze the raw data of cosmic microwave background radiation recorded by the Planck satellite, you will find that the universe seems to be more closed. These measurements are not significant enough to be considered conclusive, but are still instructive. This is interesting, because everything that is now known through the Big Bang theory suggests that our universe should be very, very flat.
What happened? Based on planck satellite data, we have two possible options:
(1) Planck satellite data show the fact that the universe may be curved;
(2) Planck’s data fooled us, either the instrument itself was faulty or other astronomical sources (such as nasty interstellar dust) made the universe look curved, but in fact, the universe is still flat.
The Planck project team conducted a lot of analysis and inspection and concluded that our universe was indeed flat, but some foreign pollution affected the data, making it appear curved.
In recent studies, however, three astronomers conducted their own analysis and came to the opposite conclusion: Planck satellite data is not deceptive, and the universe is indeed curved.
What’s the answer?
Ask a detective and they’ll tell you that eyewitness testimony is always insecure. You need multiple unrelated people to give a similar description of the same thing before you can paint a reliable picture. So, in order to determine whether the Planck satellite lied to us, we need to ask some other “witnesses.” Thankfully, cosmologists have a lot to learn from, and rich measurements can tell us about the actual curvature of the universe.
The Planck team took a straightforward approach. The researchers combined data from the Planck satellite with other observations to mix them in a statistically reasonable way to explore the curvature of the universe by combining the combined data sets. The final answer is: there is no curvature at all;
The Planck team’s researchers say their own data are not entirely reliable in terms of curvature, and that measurements of the cosmic microwave background must be combined with other cosmic probes to get an accurate answer.
But the three astronomers took a different approach. They believe the Planck satellite’s data show the fact that the universe is curved. So when they mixed data from other detectors, they found that the results were contradictory, because the data from other detectors showed that we lived in a flat universe. Therefore, we need to be very careful to find out the cause of this contradiction.
So, did Planck satellite data lie to us? ‘Yes, and the three astronomers, who happen to be members of the Planck collaboration, gave a negative answer, ‘ the Planck team said. The traditional model of cosmic expansion points to a flat universe, which is the primary reason why most scientists support the “flat universe”. While the curved universe may seem unlikely, only more data and deeper analysis can solve the debate. (Any day)