基本相互作用
维基百科，自由的百科全书
基本相互作用為物理學中亞原子粒子間最基本的相互作用，亦稱為自然界四力。
| 名称 | 相對強度(以强相互作用为准) | 性質(對距離的作用大小) | 作用的範圍(m) | 传递相互作用的中间玻色子 |
|---|---|---|---|---|
| 強相互作用 | 1 | 1/r7 | 10-15 | 膠子 |
| 电磁相互作用 | 1/137 | 1/r2 | 無限大 | 光子 |
| 弱相互作用 | 10-13 | 1/r5 - 7 | 10-18 | W 及 Z 玻色子(W±,Z0) |
| 重力相互作用 | 10-39 | 1/r2 | 無限大 | 重力子 |
目前的大统一理论認為：強相互作用、弱相互作用和电磁相互作用可以統一成一種相互作用，目前统一弱相互作用和電磁相互作用的电弱统一理论已經獲得實驗證實.
[编辑] 引力相互作用
- 主条目: 万有引力
引力相互作用是四个基本相互作用中最弱的，但是同时又是作用范围最大的即超矩。The term long range refers technically to the falling off of the interaction with distance r at a rate equal to 1/r2. 不像其他的相互作用, 重力广泛地作用于所有的物质。由于其广泛的作用范围, 仅 与物质质量有关的属性以及與物質的帶電量無關等，most interactions between objects separated by length scales larger than that of a planet, for example, are predominantly due to gravity.
由于其广泛的作用范围。 引力是大范围天文现象产生的原因，比如：银河系， 黑洞 和 宇宙膨胀；以及更多的基本天文现象，比如：行星的公转； 还有以下下生活常识，物体下落；很重的物体好像被固定在地上，人不能跳得太高等等。
万有引力是第一种被数学理论描述的相互作用。在古代，亚里士多德 建立了具有不同质量的物体是以不同的速度下落的理论。 在科学革命时期， 伽利略·伽利莱 用试验推翻了这个理论 － 如果忽略空气阻力，那么所有的物体都会以相同的速度落向地面。 艾萨克·牛顿的万有引力定律 (1687) 是一个用来描述通常重力行为非常好的近似。 在1915年, 阿尔伯特·爱因斯坦 完成了 广义相对论，将重力用一种更精确的方式描述－时空几何。
如今，一个活跃的领域正致力于用一个使用范围更广的理论来统一广义相对论和量子力学－大统一理论。在量子力学中，一个在量子引力理论中设想的粒子－引力子被广泛地认为是一个传递引力的粒子。引力子仍是假想粒子，目前还没有被观测到。
尽管广义相对论在非量子力学限制的情况下较精确地描述了引力，但是仍有不少描述万有引力的替代理论。这些在物理学界严格审视下的理论都是为了减少一些广义相对论的局限性，而目前观测工作的焦点就是确定什么理论修正广义相对论的局限性是可能的。
- Main article: Gravity
Gravity is by far the weakest interaction, but it is the interaction that has the largest range. The term long range refers technically to the falling off of the interaction with distance r at a rate equal to 1/r2. Unlike the other interactions, gravity works universally on all matter and energy. Because of its long range, and property of depending only on the mass of objects and independent of their charge etc., most interactions between objects separated by length scales larger than that of a planet, for example, are predominantly due to gravity.
Because of its long range, gravity is responsible for such large-scale phenomena as the structure of galaxies, black holes and the expansion of the universe, as well as more elementary astronomical phenomena like the orbits of planets, and everyday experience: objects fall; heavy objects act as if they were glued to the ground; people are unable to jump very high.
Gravitation was the first kind of interaction which was described by a mathematical theory. In ancient times, Aristotle theorized that objects of different masses fall at different rates. During the Scientific Revolution, Galileo Galilei experimentally determined that this was not the case - if friction due to air resistance is neglected, all objects accelerate toward the ground at the same rate. Isaac Newton's law of Universal Gravitation (1687) was a good approximation of the general behaviour of gravity. In 1915, Albert Einstein completed the General Theory of Relativity, a more accurate description of gravity in terms of the geometry of space-time.
An area of active research today involves merging the theories of general relativity and quantum mechanics into a more general theory of quantum gravity. It is widely believed that in a theory of quantum gravity, gravity would be mediated by a particle which is known as the graviton. Gravitons are hypothetical particles not yet observed.
Although general relativity appears to present an accurate theory of gravity in the non-quantum mechanical limit, there are a number of alternate theories of gravity. Those under any serious consideration by the physics community all reduce to general relativity in some limit, and the focus of observational work is to establish limitations on what deviations from general relativity are possible.
