Bright Sword starts with the grenade flat.

Chapter 423 Heading to Heaven

In fact, the discovery and understanding of dark energy can be traced back to the general theory of relativity, and the core of general relativity is the gravitational field equation.

But in 1917, when Einstein was solving the gravitational field equations, he discovered that the results of his calculations showed that the universe is dynamic and that it is either collapsing or expanding.

But most physicists of that era believed that the universe was static and finite. It was difficult for them to accept the concept of a dynamic universe. So Einstein added a constant to the gravitational field equation to avoid the gravitational field equation being the result of a dynamic universe.

This constant is the famous cosmological constant Λ. In fact, after adding the cosmological constant to the gravitational field equation, it does not mean that the result calculated by the gravitational field equation must be a static universe. But at least there is a solution to the static universe.

However, in 1924, Hubble discovered that most galaxies were moving away from the Milky Way. The farther the galaxy was, the faster it was receding, which indicated that the universe was expanding.

At first, Einstein was unwilling to believe the fact that the universe was expanding. Later, he went to the observatory to observe it in person, and was forced to give up his views. In 1931, he admitted that adding the cosmological constant to the gravitational field equation was the biggest mistake of his life.

Einstein then removed the cosmological constant from his gravitational field equations.

The cosmological constant was not resurrected until 1, because in that year, astronomers captured the spectral lines of a Type a supernova explosion and, through analysis of the redshift, discovered that the universe was expanding at an accelerating rate.

This discovery not only foreshadowed the revival of the cosmological constant, but also the discovery of dark energy. Later, the three physicists who discovered that the universe is expanding at an accelerating rate also won the 2011 Nobel Prize in Physics.

In fact, before 1998, although astronomers knew that the universe was expanding, they generally believed that this expansion was driven by the aftermath of the Big Bang. It was a decelerating expansion. Then, under the influence of gravity, the universe would stop expanding, then begin to contract, and finally the entire universe would collapse into a singularity.

The discovery in 1998 that the universe is expanding at an accelerating rate overturned all previous assumptions. At the time, some people even doubted the correctness of the gravitational field equation.

Previously, in the universe model of decelerating expansion, since the concept of repulsion did not exist, the gravitational field equations explained the decelerating expansion perfectly.

But then, faced with the fact that the universe is expanding at an accelerated rate, the gravitational field equations become difficult to explain.

So from that time on, the view that general relativity might be a limited theory was popular.

The limitation theory is to downgrade the general theory of relativity. It no longer considers the general theory of relativity as a universal theory of gravity in the universe, but is a limitation theory like Newton's theory of gravity. Newton's theory of gravity is applicable to weak fields and small-scale gravitational phenomena in the star system.

The general theory of relativity is not only compatible with Newton's theory of gravity, but also applies to gravitational phenomena of strong fields such as black holes and neutron stars. As for the accelerated expansion phenomenon at super-macroscopic scales, new theoretical explanations are needed, such as the repulsion theory.

But this view is hard to accept. After all, if both gravity and repulsion exist in the universe, where is the dividing line between repulsion and gravity? Why is repulsion not gravity at the supermacroscopic scale?

Therefore, although physicists have accepted the concept of repulsion, they believe that repulsion and gravity exist simultaneously in the universe, with no scale boundary. There is another explanation for why super-macroscopic scales manifest as repulsion.

This is the dark energy hypothesis, which holds that dark energy is evenly distributed in the universe. Dark energy exhibits repulsive effects, driving the accelerated expansion of the universe.

Furthermore, dark energy can find support in the cosmological constant.

In the gravitational field equation, the positive value of the cosmological constant represents repulsion. Therefore, in the gravitational formula with the cosmological constant added, objects will be affected by both gravity and repulsion at the same time.

Generally speaking, gravity still dominates on the scale of galaxies, but when the spatial scale exceeds tens of millions of light years, repulsion begins to dominate.

This explains a confusion that many people have. We all know that the universe is expanding at an accelerating rate, but the Andromeda Galaxy, which is closest to the Blue Star, is approaching the Milky Way at a speed of 110 kilometers per second and is expected to collide with the Milky Way in 4.5 billion years.

In fact, this is not a contradiction, because the Milky Way is only 2.5 million light-years away from the Andromeda Galaxy. At this scale, gravity still dominates. If it is farther away, repulsion will dominate.

The current mainstream view in academia is that after adding the cosmological constant to the gravitational field equation, the repulsive force at the ultra-macroscopic scale is dominated by dark energy, which is also the driving force for the accelerated expansion of the universe.

That's right, it sounds ridiculous, but this is actually the case. Dark energy is deduced just like dark matter. Because the numbers calculated using the mathematical model of gravity are seriously inconsistent with the observed phenomena, we have to use a cosmological constant, that is, the dark energy hypothesis, to achieve self-consistent balance.

However, since dark energy does not participate in gravity and is not attracted by gravity, it is more difficult to confirm dark energy than dark matter.

You should know that the Dark Matter Research Institute founded by Liu Xiu has made some breakthroughs in the study of dark matter.

The most critical one is the alien unmanned spacecraft that originally landed on Titan. Because of the curvature engine technology on it, the humans wandering on the blue planet have learned how to manufacture curvature engines.

To be honest, if there wasn’t that unmanned spacecraft, the wandering blue planet would probably still be floating in the universe!
After all, if there was no curvature engine, the final outcome of the Wandering Blue Planet would naturally be the same as in the original plot, reaching the Proxima Galaxy after drifting for 2,500 years, instead of reaching the Proxima Galaxy in just over ten years.

It is precisely because the curvature engine essentially masters the method of artificially creating gravity that dark matter is attracted by artificial stress.

It's a pity that dark matter does not react to electromagnetic force, so a very funny thing happened. Although a large amount of dark matter was attracted by artificial gravity, it could not be used.

After all, whether studying dark matter or dark energy, its essence is naturally for one thing, which is to convert it into usable energy.

This is like heavy nuclear fusion. This technology can turn stones that seemed useless and could only be used as building materials into fuel that can propel the blue planet.

Using a large amount of energy to generate strong gravitational force has attracted a large amount of dark matter, and naturally people want to use it and turn it into energy or other materials owned by humans.

However, even though the Dark Matter Research Institute has not figured out how to use dark matter at this stage, Liu Xiu has not given up on allocating research funds to the Dark Matter Research Institute, and has even increased it.

After all, Liu Xiu was mentally prepared for the huge amount of funding required for scientific research, especially theoretical physics.

Of course Liu Xiu did not give up on his research in theoretical physics, but now he was faced with a choice.

That’s right, the decision is whether or not to go to Paradise, the hometown of the Engineer Civilization!
(End of this chapter)