Consolidated Grant 2015

2015年综合赠款

基本信息

批准号：
ST/N000331/1
负责人：
Themistocles Bowcock
金额：
$ 869.59万
依托单位：
University of Liverpool
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2015
资助国家：
英国
起止时间：
2015 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=ST%2FN000331%2F1
关键词：
Consolidated Grant 2015

项目摘要

The research of the experimental particle physics group addresses some of the main questions in fundamental physics. One of the most pressing is what is the mechanism that is behind the overwhelming dominance of matter over anti-matter in the Universe? Matter and anti-matter should have been created in equal quantities in the early Universe, yet the gross difference in their natural occurrence is a defining feature of what we observe. Without this asymmetry life could not exist. We believe that neutrinos may hold the key to understanding the matter-antimatter asymmetry. Neutrinos, discovered almost a century ago, are the most evanescent of particles. They have no charge, barely interact with matter and were long thought to be completely massless (like a photon). They can travel through the earth with only the tiniest probability of leaving a trace. To detect neutrinos we have had to build enormous but very sensitive detectors. Our experiments show that neutrinos actually have a very small but significantly non-zero mass. This small non-zero mass allows them to drive the matter-antimatter asymmetry in the early Universe. An important part of our research is to make detailed measurements of the neutrinos, to understand their masses and to calculate if their properties are indeed those required to explain the matter-antimatter dominance.The discovery of the Higgs particle was one of the most important in the last decade. It confirmed the existence of a fundamentally new type of "force" that pervades all of nature and gives mass to elementary particles. Without the Higgs, particles such as electrons could not bind to protons to make hydrogen atoms. Thus normal atomic matter, even stars, could not be formed. We continue to study the Higgs to measure and understand its properties. We are especially interested to see if the Higgs particles provides a window to what we call the "dark universe". It has long been known that there is not enough visible matter in the Universe to explain the speed at which galaxies rotate. There are simply not enough stars. The only explanation appears to be that surrounding us, and in all galaxies, there is a halo of invisible matter which exerts a gravitational influence (hence why the galaxies spin as fast as they do) but which does not interact with light. Calculations suggest there is 5 times more of this dark matter than visible matter in the Universe. The Higgs could interact with dark matter, thus we can use the Higgs to "illuminate" the dark sector for the first time. This is an important part of our research. Observations also suggest that the Universe is inflating, as if there is pressure created by space itself. This process is observed but non-understood. It strongly suggests there is another form of dark energy at work. Altogether the dark universe accounts for 95% of the matter/energy in the Universe with only 5% (that we can observe) being luminous. This makes the study of the dark matter and energy absolutely central to our understanding of the fundamental nature of our world. Thus we have joined experiments whose aim is to try and study and uncover the true nature of dark energy.Our theory of how all particles interact is embodied in what is called the Standard Model. With the exception of neutrinos and their masses it has enormous predictive power and provides a simple framework for elucidating the nature of the universe. Following the scientific method we continue to refine and test the SM at the energy frontier and with dedicated precision experiments. This provides another, and well tested route, to the discovery of new physics.

实验粒子物理组的研究解决了基本物理学中的一些主要问题。最紧迫的之一是，在宇宙中，物质占主导地位的机制是什么？物质和反物质应该在早期的宇宙中相等地创建，但是自然发生的总差异是我们观察到的定义特征。没有这种不对称的生活就不可能存在。我们认为，中微子可能是理解物质抗物类不对称的关键。中微子大约一个世纪前发现，是颗粒中最偏见的。他们没有电荷，几乎没有与物质相互作用，长期以来被认为是完全无质量的（如光子）。他们只能以留下痕迹的最小概率穿越地球。要检测中微子，我们必须建立巨大但非常敏感的探测器。我们的实验表明，中微子实际上的质量很小但显着非零。这个小的非零质量使他们能够在早期宇宙中驱动物质抗逆点的不对称性。我们研究的一个重要部分是对中微子进行详细的测量，了解其质量，并计算其特性是否确实是解释物质 - 抗位于统治性的所需的。希格斯粒子的发现是过去十年中最重要的。它证实了一种从根本上存在的“力”的存在，该“力”遍布所有自然界，并赋予基本颗粒的质量。没有希格，电子等颗粒就无法与质子结合以制造氢原子。因此，无法形成正常的原子质，甚至是恒星。我们继续研究希格斯以衡量和理解其特性。我们特别有兴趣看看希格斯粒子是否为我们所谓的“黑暗宇宙”提供了一个窗口。早就知道，宇宙中没有足够的可见物质来解释星系旋转的速度。根本没有足够的星星。唯一的解释似乎是在我们周围，在所有星系中，都有一个无形物质的光环会产生引力影响（因此为什么星系会像它们一样快地旋转），但不会与光相互作用。计算表明，这种暗物质是宇宙中可见物质的5倍。希格斯可以与暗物质相互作用，因此我们可以首次使用希格（Higgs）“照亮”黑暗扇区。这是我们研究的重要组成部分。观察结果还表明宇宙正在膨胀，好像空间本身会产生压力。观察到这个过程，但没有理解。强烈表明，工作中还有另一种形式的黑能。黑暗的宇宙总共占宇宙中物质/能量的95％，只有5％（我们可以观察到）是发光的。这使得对深色物质和能量的研究绝对是我们对我们世界基本本质的理解的核心。因此，我们加入了实验，其目的是尝试研究和揭示深色能量的真实本质。我们关于所有粒子相互作用的理论都在所谓的标准模型中体现。除了中微子及其质量外，它具有巨大的预测能力，并提供了一个简单的框架来阐明宇宙的性质。遵循科学方法，我们继续在能量前沿和专用精度实验上完善和测试SM。这为发现新物理学提供了另一条经过良好测试的路线。