presenting the background
In 1915, I cherry, I have established a broad relativity, and the first application he gives is quantitatively explaining the problem of Mercury near-Japan (ie, to explain Newton gravity. Theoretically cannot explain the part). Therefore, in principle, it can be said that from the birth of a broad relativity, it is also born at the same time. However, in 1915, in addition to the geometric cosmology, broad relativity has not had a big impact on the geophysical physics. This is because the gravitational field is too weak in the "usual" celestial object, and there is no need to apply generalized relativity. For the "usual" astrophysics, generalized relativity and Newtonian gravity theory are very small in order. In the solar system, only gravitational red shifts, light deflection, Mercury near-date, and radar signals are related to generalized relativism (see astronomical verification of broad relativity).
The strength of the gravitational field of a system can be measured with the ratio of the system's scale R with its gravitational radius r g. r g 呏 gm / c 2, where m is the quality of the system, G is a genericity constant, C is the radius. If the ratio of the system Rg / R "1, it belongs to the weak field; if rg / r≈1, it belongs to the strong field. The following table lists the RG / R values of some common celestial bodies: they are far less than 1, which is the basis for the theory of Newton. You can also see this problem from another angle. If the gravitational field produced by the mass M system is strong, their spatial scale R. In other words, if you want to turn the system of mass M into the source of the strong gravitational field, it should compress this system to the R such a small spatial range. For example, only the sun is compressed into a few tens of kilometers of diameter, it can become a strong field.
According to the experience from the ground laboratory, this compression is considered completely impossible. However, in the 1930s, the gravity collapse concept of the celestial body was proposed. This concept is to say that a celestial system, under its own gravity, it is always unlimited to collapse. After a more careful theoretical analysis, this concept is certain. In summary, a high-quality star, cannot get rid of the ending of the gravity collapsed. The existence of gravity itself will inevitably lead to the existence of strong gravitational field. According to this conclusion, the space between the universe must not necessarily have a strong gravitational field, but also a lot. Astronomical observations in the 1960s have gradually confirmed this view. One of the key steps is about the study of crab-shaped cloud pulse stars. The crab-like nebula is a 1054 supernova remains. Its center has a star, observed that it is a pulse star, only 33 milliseconds of the pulse cycle, and the cycle is very stable, indicating that this is caused by rotation. The pulse cycle is extremely short, indicating that the spatial scale of the rotary celestial body is small. On the other hand, the pulse star is very large, and its quality is not too small. Such a large mass and small volume is exactly the denseness formed after the gravity collapsed. 1054 super new star broke out is a manifestation of gravitational collapses. Astronomical observations have also found some other types of mostrictions with strong gravitational fields, and its R g / r value is listed in the table: the first result of relativistic physics That is to find that there are many types of celestial bodies with strong gravitational field in nature, which is large, which completely changes the old universe.
Content composition
Relatively, the heavenger physics includes the following aspects:
relatively on the universe
This is the earliest branch. It studies the large-scale time and space structure and geometric characteristics of the universe. At present, there is an impact on the expansion cosmic model, large explosion cosmology, etc.
Deterministic physics
Research of the stars nuclear energy depleted the gravitational collapse process, and the solid stars formed after collapse, such as Dwarf, neutron star, black hole, etc.
Gravitational Waves
to study the gravitational wave emissions of various celestial processes, and the effect of gravitational radiation on the surface of the heave. Directly detect the work of the celestial emission gravity wave, also in progress.
Newtonian Mechanics
Research Generalized Relativity on "Ordinary" Eastern Mechanics (ie, the theory of Newton'soretical Theory) . For example, the relative discussion of the near-star point of the double star, the relative discussion of the self-rotating shaft, and the like.Tested various gravitational theories with the motion properties of the heavens, and is also an important aspect of the physical physics of the heavens. Several main prophesies of general relativity, such as light deflection, universe expansion, existence of gravitational waves, are first tested by astronomical observations. Therefore, relatively disciplinary physical physics is not only a generalized relativism application discipline, but also a basic discipline for exploration of gravitational law.