완전과 거리가 멀지만 여전히 굉장한 standard model 소립자 물리학의 표준 모형
자료: wikipedia
The Standard Model of particle physics is a theory concerning the electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of the known subatomic particles. Developed throughout the mid to late 20th century, the current formulation was finalized in the mid 1970s upon experimental confirmation of the existence of quarks. Since then, discoveries of the bottom quark (1977), the top quark (1995), and the tau neutrino (2000) have given further credence to the Standard Model. Because of its success in explaining a wide variety of experimental results, the Standard Model is sometimes regarded as a "theory of almost everything".
The Standard Model falls short of being a complete theory of fundamental interactions because it does not incorporate the physics of dark energy nor of the full theory of gravitation as described by general relativity. The theory does not contain any viable dark matter particle that possesses all of the required properties deduced from observational cosmology. It also does not correctly account for neutrino oscillations (and their non-zero masses). Although the Standard Model is believed to be theoretically self-consistent, it has several apparently unnatural properties giving rise to puzzles like the strong CP problemand the hierarchy problem.
Nevertheless, the Standard Model is important to theoretical and experimental particle physicists alike. For theorists, the Standard Model is a paradigmatic example of a quantum field theory, which exhibits a wide range of physics includingspontaneous symmetry breaking, anomalies, non-perturbative behavior, etc. It is used as a basis for building more exotic models that incorporate hypothetical particles, extra dimensions, and elaborate symmetries (such as supersymmetry) in an attempt to explain experimental results at variance with the Standard Model, such as the existence of dark matter and neutrino oscillations. In turn, experimenters have incorporated the Standard Model into simulators to help search for new physics beyond the Standard Model.
Recently, the Standard Model has found applications in fields besides particle physics, such as astrophysics, cosmology, and nuclear physics.
The Standard Model of elementary particles, with the gauge bosons in the rightmost column. (Higgs boson not shown here.)
소립자 물리학의 표준 모형(標準模型, Standard Model)은 자연계의 기본 입자와, 중력을 제외한 그 상호작용 (강한 상호작용, 약한 상호작용, 전자기 상호작용)을 다루는 게이지 이론이다. 강력을 다루는 양자색역학과, 약력과 전자기력을 다루는 와인버그 살람 이론으로 이루어진다. 표준 모형에 따르면, 전자와 중성미자 및 기타 렙톤은 기본 입자이나, 하드론은 쿼크로 이루어진다. 이들은 게이지 보존에 의하여 상호작용한다. 게이지 보존은 이론의 대칭을 나타낸다. 표준 모형의 대칭 가운데 강한 상호작용의 대칭은 가둠으로 인하여 간접적으로만 관찰할 수 있고, 약한 상호작용의 대칭은 힉스 메커니즘으로 인하여 깨진다. 따라서 거시적으로는 전자기 상호작용의 대칭만 쉽게 관찰할 수 있다. 표준 모형은 실험적으로 힉스 메커니즘을 제외하고 1980년대에 완성되었다. 힉스 메커니즘은 표준 모형에서 중요한 역할을 하나, 아직 실험적으로 검증되지 않았다.