Searches for Beyond the Standard Model Physics with Hadronic Topologies

物理学家想要确定宇宙最基本的组成部分以及它们是如何相互作用的。目前，我们最好的理论被称为标准模型（SM）。它解释了磁场和电流是如何与放射性原子核衰变以及将质子聚集在一起的力相关的。然而，SM内部和外部都存在许多悬而未决的问题。例如，95%的已知宇宙和引力都不能被SM描述。暗物质只涉及可见的宇宙，而大多数物质不发射或吸收光：被恰当地称为暗物质（DM）。通过观察星系和星系团中恒星的引力效应，我们怀疑暗物质占宇宙质量的84%。由于DM与可见物质的相互作用非常弱，所以还没有在地球上观测到。一些解释暗物质的尝试很简单，只包括一种新的粒子和介质——暗世界和可见世界之间的桥梁。其他的，比如超对称理论，一个非常流行的SM扩展，预测了许多新粒子，其中一个可能是dm。厨房里的磁铁能让回形针顶住整个地球的引力。一种解释是，宇宙包含了不止四个维度，而我们在这四个维度中只感受到全部引力潜力的一小部分。作为科学家，我们为无法解释的现象（如上面提到的那些）找到可能的答案，并设计实验来检验我们的想法；有时我们会发现完全出乎意料的事情。大型强子对撞机（LHC）就是为此目的而建造的。大型强子对撞机以非常高的能量将质子撞击在一起，创造出所有的SM粒子，希望还有一些以前从未见过的粒子！DM粒子本身或DM介质可以在质子-质子碰撞中产生。关注引力的高维理论预测了在大型强子对撞机能量下黑洞的产生。如果这些理论和其他许多解决重大物理问题的理论是正确的，它们预测LHC将产生新的粒子，并衰变为喷射——高能的SM粒子的准直喷雾。这种衰变数量的过剩将意味着我们已经发现了新的物理学，并彻底改变了我们对宇宙的理解！随着每一次发现，新的物理学都让我们对宇宙最基本的运作方式有了更深入的了解。它改变了我们对宇宙的理解以及我们生活在宇宙中的方式。电子的发现使我们能够利用电力和磁体的力量，理解原子的规则产生核能为我们的城市供电，爱因斯坦的相对论使全球定位系统能够在这个美丽的星球上找到我们的路。物理学家开发的技术具有惊人的进步潜力，例如，万维网就是在欧洲核子研究中心创建的。政府、企业、金融机构、甚至运动队都聘用物理学家来分析数据和解决复杂的问题，他们在海量数据集上接受过严格的科学方法训练。然而，对我来说，诺贝尔奖得主史蒂文·温伯格（Steven Weinberg）的话最好地概括了从基本层面理解自然的原因，他写道：“理解宇宙的努力是为数不多的几件事之一，它使人类的生活略高于闹剧的水平，并赋予它一些悲剧的优雅。”

Physicists want to determine the most fundamental building blocks of the Universe and how they interact. Currently, our best theory is called the Standard Model (SM). It explains how magnetic fields and electrical currents are related to radioactive nuclei decay and the force that holds a proton together. However, many open questions exist within and beyond the SM. Neither ~95% of the known universe nor gravity is described by the SM, for instance.The SM deals only with the visible Universe, while the majority of matter does not emit or absorb light: aptly named dark matter (DM). By looking at gravitational effects on stars in galaxies and clusters of galaxies, we suspect DM comprises ~84% of the Universe's mass. DM has not yet been observed on Earth because it may interact very weakly with visible matter. Some attempts to explain DM are simple and only include one new particle and mediator - the bridge between the dark and visible worlds. Others, such as Supersymmetry, a very popular SM extension, predict many new particles, one of which could be DM.Gravity is very weak. A kitchen magnet holds a paper clip against the gravitational pull of the entire Earth. One explanation is that the Universe contains more than four dimensions, and we only feel a fraction of the full gravitational potential in our four.As scientists, we develop possible answers to unexplained phenomena, such as those mentioned above, and devise experiments to test our ideas; sometimes we find the completely unexpected. The Large Hadron Collider (LHC) was built for this purpose. The LHC smashes together protons at very high energies to create all the SM particles and hopefully a few never seen before! DM particles themselves or the DM mediator can be created in proton-proton collisions. The higher dimensional theories focusing on gravity predict the creation of black holes at LHC energies. These and a host of other theories tackling the big physics questions, if true, predict new particles will be produced by the LHC and decay into jets - highly energetic collimated sprays of SM particles. An excess in the number of such decays would signify that we have found new physics and revolutionize our understanding of the Universe!With every discovery, the new physics gives insight to the most fundamental workings of the Universe. It changes our understanding of the Universe and the way we live in it. The discovery of the electron allowed us to harness the power of electricity and magnets, understanding the rules of the atom yielded nuclear energy to power our cities, and Einstein's theory of relativity enabled Global Positioning Systems to find our way across this beautiful planet. Technologies developed by physicists have amazing potential for progress, and the World Wide Web for example was created at CERN. Physicists trained in the rigors of the scientific method on tremendous datasets are employed by governments, businesses, financial institutions, and even sports teams to analyze data and solve complicated problems. Nevertheless, for me, the reason to understand nature at a fundamental level is best encapsulated by the Nobel laureate Steven Weinberg when he wrote, "The effort to understand the Universe is one of the very few things which lifts human life a little above the level of farce and gives it some of the grace of tragedy."