Shock Waves and the Vacuum Structure of Gauge Theories
请给出一篇以提问问题开篇的英语范文
请给出一篇以提问问题开篇的英语范文全文共3篇示例，供读者参考篇1What is the most effective way to study for exams? This question is one that has puzzled students for generations. With so much information to memorize and understand, it can be overwhelming to find a study method that works best for you. However, there are several strategies that have been proven to be successful in helping students prepare for exams.One of the most important aspects of studying is creating a study schedule. By setting aside specific times each day to review material and practice test questions, you can ensure that you are adequately prepared for your exams. In addition, it is essential to break up your study sessions into smaller, manageable chunks to avoid becoming overwhelmed.Another key to successful studying is finding a quiet and comfortable study environment. Whether it's a quiet corner in the library or a cozy spot in your bedroom, having a designated study space can help you focus and retain information more effectively. Eliminating distractions such as loud noises andinterruptions from friends or family members is crucial for optimal studying.When it comes to actually studying the material, there are several techniques that can be beneficial. Some students find that making flashcards or outlines can help them organize information and test their knowledge. Others prefer to form study groups to review material and quiz each other on key concepts. Find what works best for you and stick to it.Finally, it is important to take care of your physical and mental health during the exam period. Make sure to get enough sleep, eat nutritious meals, and take breaks to relax and recharge. Remember, your health is just as important as your academic success.In conclusion, there is no one-size-fits-all approach to studying for exams. It is essential to experiment with different techniques and strategies to find what works best for you. By creating a study schedule, finding a quiet study environment, utilizing effective study techniques, and taking care of your health, you can set yourself up for success on your exams. Good luck!篇2Title: Can Asking Questions Lead to Deeper Understanding?Have you ever considered the power of questions? From sparking conversations to solving complex problems, questions play a crucial role in our daily lives. They can lead to new discoveries, challenge assumptions, and foster critical thinking. But can asking questions actually lead to a deeper understanding of the world around us?To explore this idea, let's first consider the nature of questions. Questions are a way of seeking information, clarifying concepts, and exploring possibilities. By asking questions, we engage with our surroundings and actively seek knowledge. This act of inquiry can drive curiosity and motivation, propelling us to delve deeper into a topic or issue.Moreover, questions can serve as a tool for reflection and introspection. When we ask ourselves questions, we are forced to examine our beliefs, values, and assumptions. This process of self-examination can lead to personal growth and a deeper understanding of ourselves.In educational settings, questioning plays a fundamental role in the learning process. Teachers often use questions to gauge students' understanding, prompt critical thinking, and encourage active participation. By encouraging students to askquestions, educators foster a culture of inquiry and promote intellectual engagement.Furthermore, questions can drive innovation and problem-solving. In fields such as science, technology, and business, asking the right questions can lead to breakthrough discoveries and revolutionary advancements. By challenging existing paradigms and pushing boundaries, questions fuel progress and drive innovation.In conclusion, asking questions is not merely a tool for seeking information, but a powerful means of deepening understanding. Through questions, we can challenge assumptions, spark curiosity, foster critical thinking, and drive innovation. So next time you encounter a question, remember the potential it holds to lead you to a deeper understanding of the world around you.篇3Title: Can Asking Questions Lead to Discovery?Introduction:Have you ever realized that asking questions can actually lead to discovering something new and inspiring? Questions have the power to ignite curiosity, drive exploration, andstimulate critical thinking. From a young age, we are encouraged to ask questions to deepen our understanding of the world around us. But, have you ever considered the profound impact that questioning can have on scientific discovery, technological innovation, or even personal growth?In this essay, we will explore the power of asking questions and how it can lead to new discoveries in various fields. We will examine the role of inquiry in scientific research, the importance of curiosity in technological advancements, and the transformative effect of self-reflection and introspection. By delving into these topics, we hope to illuminate the inherent value of questioning and inspire you to embrace the spirit of inquiry in your own life.Role of Inquiry in Scientific Research:Scientific research is founded on the principle of inquiry –the relentless pursuit of answers to questions that drive our understanding of the natural world. Without questioning the status quo, challenging existing theories, and exploring uncharted territories, scientific progress would come to a standstill. Take, for example, the field of astronomy. By asking questions about the nature of celestial bodies, the structure of the universe, and the origins of galaxies, astronomers have madeastonishing discoveries that have revolutionized our understanding of the cosmos. From the discovery of exoplanets to the detection of gravitational waves, questioning lies at the heart of scientific advancement.Importance of Curiosity in Technological Advancements:Curiosity is the driving force behind technological advancements that shape our modern world. Consider the smartphone in your pocket – a marvel of engineering that has revolutionized communication, entertainment, and productivity. This groundbreaking device was born out of a series of questions that challenged the limitations of existing technology. How can we make phones smarter, faster, and more intuitive? How can we integrate multiple functions into a single device? By asking these questions and pushing the boundaries of innovation, engineers and designers have transformed the way we live, work, and connect with one another.Transformative Effect of Self-Reflection and Introspection:Questions are not only instrumental in external exploration but also in internal reflection. By probing our own thoughts, beliefs, and emotions, we can gain valuable insights into our motivations, values, and aspirations. Self-reflection allows us to question our assumptions, challenge our biases, and cultivate adeeper understanding of ourselves and others. Through introspection, we can uncover hidden truths, confront difficult truths, and embark on a journey of personal growth and transformation. By asking questions that prompt us to examine our innermost selves, we can unlock new possibilities, overcome obstacles, and discover our true purpose in life.Conclusion:Asking questions is not just a means of seeking answers – it is a catalyst for discovery, exploration, and innovation. By embracing the spirit of inquiry, we can unlock new horizons, challenge the boundaries of knowledge, and uncover hidden truths waiting to be revealed. So, the next time you find yourself pondering a question, don't hesitate to ask. Who knows what remarkable discoveries and insights you may uncover along the way?。
Lhc——精选推荐
On LHC,Supersymmetry and Mathematics1One of the most exciting experiments of physics has just commenced at CERN.The Large Hadron Collider,LHC collides two beams of proton moving with almost the speed of light,with a center of mass energy eventually targeted to be10TeV,about5times higher energy than the highest energy currently reached at the colliders.By probing this region in energy we expect to be able to answer some of the most important questions that fundamental physics has tried to answer in the past forty years.A key missing ingredient in what is called the Standard Model of particle physics is a particle known as‘Higgs’which is predicted to exist based on electroweak symmetry breaking.Moreover all particles we know of are believed to receive their mass through their interactions with a condensate of the Higgsfield.While the discovery of Higgs particle would be spectacular confirmation of decades long anticipation of theoretical physicists,that may not end up being the most exciting find of the LHC.Through astrophysical and cosmological observations we know that the matter making up the universe is made up mostly of unknown matter.Moreover,simple estimates of the energy range relevant for probing this‘dark matter’suggests that the LHC energy is roughly the right range for producing such matter.LHC may end up producing the dark matter and thus solving another puzzle of physics.The main theoretical question is what do we expect this extra matter to be?Over the past few decades,string theory, with deep links to mathematics,has emerged as a prime candidate for unification of forces with gravity and for providing a consistent framework for a quantum theory of gravity.It is natrual to ask if string theory can make predictions for what this extra matter may be?One important symmetry of string theory at the shortest distance scale is Supersymmetry.This is a symmetry which relates bosons and fermions together.In other words,for each particle there would exist its supersymmetric partner,whose spin differs by1/2,with otherwise exactly the same properties.We know that this cannot be the case at the larger length scales that we have performed experiments.For example there is no partner to electron (‘selectron’)which has the same mass and charge as the electron but that it has spin0. Thus supersymmetry,even if a true symmetry of nature at shortest distance scale,must be broken at longer distance scales.Supersymmetry has also played a key role in connecting1A version of this article appeared in CMI annual report20091modern physics with mathematics.In particular in the context of topologicalfield theories initiated by Witten,the concept of supersymmetry is a key ingredient.These include a deeper understanding of Donaldson invariants for smooth4-manifolds,and a significant impact on understanding of enumerative geometry.Thus supersymmetry is aesthetically and mathematically a very rich structure.Since we know that this symmetry is not realized at the lowest energy scales,the main question thefore for string theory would be to explore at what scale this symmetry is broken.If it is broken at a very short distance(high energy) scale,there would be no leftover imprint of it at the scale that LHC is doing its experiment. This is entirely possible,though unfortunate!However,there are good reasons to speculate that supersymmetry may play a role at the LHC.One such reason is that the unification of forces works more naturally in this context.Another reason has to do with the‘hierarchy problem’which is why the mass of the Higgs particle is so low compared to the fundamental mass scale in physics, i.e.the Planck scale?Supersymmetry while it would not by itself explain why the scale is so different,it would explain why it is natrual to have this small mass scale be stable against quantum corrections.This would be the case as long as supersymmetry breaking would happen at sufficiently low energy scales.In fact,regardless of string theory,due to the above reasons,one of the most popular ideas pursued by particle theorists for models beyond the standard model has been its supersymmetric extension and its breaking at energies which leaves an imprint at the LHC energy scale.Even if one assumes that supersymmetry plays a key role at energy scales of LHC,to predict precisely what would be seen at LHC requires the knowledge of how supersymmetry is exactly broken.This involves the choice of parameters controlling this breaking which can be viewed as a choice of a point on a manifold of100+dimensions!One can make various assumptions,as particle physicists have done to narrow the region for search,but still typically the leftover region is too wide to be viewed as a definitive prediction.The one prediction that essentially all such models make is the existence of a stable dark matter which is the lightest of the supersymmetric particles.However we need to narrow down the choice of parameteres for the supersymmetry broken theory,in order to make more specific predictions for the LHC,which could thus confirm/reject such theories.Atfirst sight string theory seems not to help too much in narrowing the search for how supersymmetry breaking may appear at low energy scales.However,with some mild assumptions(that the matter and gauge forces arise from tiny regions of internal compact-ification manifold)together with some colleagues(and in particular Jonathan Heckman)2we have made some surprisingly specific predictions.This involves the study of geometry of ellipticallyfibered Calabi-Yau4-folds and translating various singularity loci in terms of ing this picture we have come to the conclusion that if supersymmetry leaves an imprint on the LHC energy scale,the lighest supersymmetric particle is gravitino(super-symmetric partner of graviton)with a mass of a100times larger than that of the electron. This is too weakly interacting to observe directly.So what is important is what is the next lightest particle?In our models this particle turns out to be semi-stable(of a lifetime in the range of a second to an hour).There are two possibilities for what this next particle is:In most parameter ranges for us it turns out to be a charged particle(known as stau), which would leave a dramatic track once it leaves the LHC detectors.There is also the less likely possibility that it would be neutral(a particle known as bino)which has no direct impact on LHC but can be discovered by the missing energy using convervation of energy.Next few years may be among the most exciting times for physicists in search of fundamental laws of nature.The discovery of supersymmetry,if it happens,is not only the most exciting new discovery of a principle of physics,but it would nicely mirror the important role it has played in providing a bridge between physics and mathematics.We will have to wait a few years and see!3。
光强涨落关联引起的LIGO后镜光热散粒噪声
1
1916 年爱因斯坦在《物理学杂志》（Annalen der Physic）上发表了著名的《广 义相对论的基础》，这是关于广义相对论的第一篇完整的论文[2]。广义相对论以其概 念的深刻，结构的严谨，内容的新颖和推论的精确直至今日依然放射着夺目的光芒。 爱因斯坦在他论文中给出了行星近日点进动的广义相对论的计算值，这个值与天文 学的观测值相符合。这是广义相对论第一个成功的例证。另外，爱因斯坦利用广义 相对论给出的场方程，在弱场近似的条件下，预言了引力波的存在。到目前为止， 广义相对论一些重大预言都被实验证实了，它们包括水星近日点的进动、光线在引 力场中的弯曲、光谱线在引力场中的频移，以及由此而延伸的关于雷达回波的延迟 等[14]。而引力波至今还没有获得直接探测的认证。
Keywords: Gravitational-wave detector, LIGO, Thermal noise
II
独创性声明
经济学原理英文
Economics Principles: An Introduction to the Study of Economics AbstractEconomics is a social science that explores the principles and theories underlying the production, distribution, and consumption of goods and services. This document provides an introduction to the fundamental concepts and principles of economics, offering a comprehensive overview of the subject. It covers essential topics such as supply and demand, market equilibrium, economic systems, and economic indicators, aiming to provide a solid foundation for further studies in economics.IntroductionEconomics is the study of how societies allocate scarce resources to satisfy human wants and needs. It provides us with a framework for understanding and analyzing various economic phenomena, ranging from individual decisions to the behavior of firms and governments. By studying economics, we can gain insights into how individuals, businesses, and governments make choices and how these choices impact society as a whole.1. Supply and DemandOne of the central concepts in economics is supply and demand. The law of supply states that as the price of a good or service increases, the quantity supplied also increases, while the law of demand states that as the price of a good or service increases, the quantity demanded decreases. The interaction of supply and demand determines the equilibrium price and quantity in a market.2. Market EquilibriumMarket equilibrium occurs when the quantity demanded equals the quantity supplied at a given price. At this equilibrium point, there is no excess supply or demand, and the market clears. Understanding market equilibrium is crucial for analyzing price and quantity changes in response to various factors such as changes in supply or demand.3. Economic SystemsEconomies can be classified into different economic systems, such as market economies, command economies, and mixed economies. A market economy relies on markets and prices to allocate resources, while a command economy is characterized by central planning and government control. Mixed economies combine elements of both market and command systems.4. Economic IndicatorsEconomic indicators provide crucial insights into the overall health and performance of an economy. Some key economic indicators include gross domesticproduct (GDP), inflation rate, unemployment rate, and interest rates. These indicators help economists and policymakers gauge the current state of the economy and make informed decisions regarding economic policy.5. Microeconomics vs. MacroeconomicsEconomics can be broadly divided into two branches: microeconomics and macroeconomics. Microeconomics focuses on the behavior of individual agents, such as consumers and firms, and their interactions in specific markets. Macroeconomics, on the other hand, deals with the overall performance of the economy as a whole, including topics like economic growth, inflation, and unemployment.ConclusionThis document has provided an introduction to the fundamental principles of economics. By understanding concepts such as supply and demand, market equilibrium, economic systems, and economic indicators, we gain a better understanding of how economies function and the factors that influence their performance. Economics plays a crucial role in shaping policies and decision-making processes at all levels of society, making it a vital field of study for individuals interested in understanding the complexities of the modern world.。
金兹堡朗道理论
Ginzburg–Landau theoryFrom Wikipedia, the free encyclopediaIn physics, Ginzburg–Landau theory, named after Vitaly Lazarevich Ginzburg and Lev Landau, is a mathematical physical theory used to describe superconductivity. In its initial form, it was postulated as a phenomenological model which could describe type-I superconductors without examining their microscopic properties. Later, a version of Ginzburg–Landau theory was derived from the Bardeen-Cooper-Schrieffer microscopic theory by Lev Gor'kov, thus showing that it also appears in some limit of microscopic theory and giving microscopic interpretation of all its parameters.Contents•1Introduction•2Simple interpretation•3Coherence length and penetration depth•4Fluctuations in the Ginzburg–Landau model•5Classification of superconductors based on Ginzburg–Landau theory•6Landau–Ginzburg theories in string theory•7See also•8References•8.1PapersIntroduction[edit]Based on Landau's previously-established theory of second-order phase transitions, Ginzburg and Landau argued that the free energy, F, of a superconductor near the superconducting transition can be expressed in terms ofa complex order parameter field, ψ, which is nonzero below a phase transition into a superconducting state and isrelated to the density of the superconducting component, although no direct interpretation of this parameter was given in the original paper. Assuming smallness of |ψ| and smallness of its gradients, the free energy has the form ofa field theory.where F n is the free energy in the normal phase, α and β in the initial argument were treated as phenomenologicalparameters, m is an effective mass, e is the charge of an electron, A is the magnetic vector potential, and is the magnetic field. By minimizing the free energy with respect to variations in the order parameter and the vector potential, one arrives at the Ginzburg–Landau equationswhere j denotes the dissipation-less electric current density and Re the real part. The first equation — which bears some similarities to the time-independent Schrödinger equation, but is principally different due to a nonlinear term —determines the order parameter, ψ. The second equation then provides the superconducting current.Simple interpretation[edit]Consider a homogeneous superconductor where there is no superconducting current and the equation for ψ simplifies to:This equation has a trivial solution: ψ = 0. This corresponds to the normal state of the superconductor, that is for temperatures above the superconducting transition temperature, T>T c.Below the superconducting transition temperature, the above equation is expected to have a non-trivial solution (that is ψ ≠ 0). Under this assumption the equation above can be rearranged into:When the right hand side of this equation is positive, there is a nonzero solution for ψ (remember that the magnitude of a complex number can be positive or zero). This can be achieved by assuming the following temperature dependence of α: α(T) = α0 (T - T c) with α0/ β > 0:•Above the superconducting transition temperature, T > T c, the expression α(T) / β is positive and the right hand side of the equation above is negative. The magnitude of a complex number must be a non-negative number, so only ψ = 0 solves the Ginzburg–Landau equation.•Below the superconducting transition temperature, T < T c, the right hand side of the equation above is positive and there is a non-trivial solution for ψ. Furthermorethat is ψ approaches zero as T gets closer to T c from below. Such a behaviour is typical for a second order phase transition.In Ginzburg–Landau theory the electrons that contribute to superconductivity were proposed to forma superfluid.[1] In this interpretation, |ψ|2 indicates the fraction of electrons that have condensed into a superfluid.[1] Coherence length and penetration depth[edit]The Ginzburg–Landau equations predicted two new characteristic lengths in a superconductor which wastermed coherence length, ξ. For T > T c (normal phase), it is given bywhile for T < T c (superconducting phase), where it is more relevant, it is given byIt sets the exponential law according to which small perturbations of density of superconducting electrons recover their equilibrium value ψ0. Thus this theory characterized all superconductors by two length scales. The second one is the penetration depth, λ. It was previously introduced by the London brothers in their London theory. Expressed in terms of the parameters of Ginzburg-Landau model it iswhere ψ0 is the equilibrium value of the order parameter in the absence of an electromagnetic field. The penetration depth sets the exponential law according to which an external magnetic field decays inside the superconductor. The original idea on the parameter "k" belongs to Landau. The ratio κ = λ/ξ is presently known asthe Ginzburg–Landau parameter. It has been proposed by Landau that Type I superconductors are those with 0 < κ< 1/√2, and Type II superconductors those with κ> 1/√2.The exponential decay of the magnetic field is equivalent with the Higgs mechanism in high-energy physics. Fluctuations in the Ginzburg–Landau model[edit]Taking into account fluctuations. For Type II superconductors, the phase transition from the normal state is of second order, as demonstrated by Dasgupta and Halperin. While for Type I superconductors it is of first order as demonstrated by Halperin, Lubensky and Ma.Classification of superconductors based on Ginzburg–Landau theory[edit]In the original paper Ginzburg and Landau observed the existence of two types of superconductors depending on the energy of the interface between the normal and superconducting states.The Meissner state breaks down when the applied magnetic field is too large. Superconductors can be divided into two classes according to how this breakdown occurs. In Type I superconductors, superconductivity is abruptly destroyed when the strength of the applied field rises above a critical value H c. Depending on the geometry of the sample, one may obtain an intermediate state[2] consisting of a baroque pattern[3] of regions of normal material carrying a magnetic field mixed with regions of superconducting material containing no field. In Type II superconductors, raising the applied field past a critical value H c1 leads to a mixed state (also known as the vortex state) in which an increasing amount of magnetic flux penetrates the material, but there remains no resistance to the flow of electric current as long as the current is not too large. At a second critical field strength H c2, superconductivity is destroyed. The mixed state is actually caused by vortices in the electronic superfluid, sometimes called fluxons because the flux carried by these vortices is quantized. Most pure elemental superconductors, except niobium and carbon nanotubes, are Type I, while almost all impure and compound superconductors are Type II.The most important finding from Ginzburg–Landau theory was made by Alexei Abrikosov in 1957. He used Ginzburg–Landau theory to explain experiments on superconducting alloys and thin films. He found that in a type-II superconductor in a high magnetic field, the field penetrates in a triangular lattice of quantized tubes offlux vortices.[citation needed]Landau–Ginzburg theories in string theory[edit]In particle physics, any quantum field theory with a unique classical vacuum state and a potential energy witha degenerate critical point is called a Landau–Ginzburg theory. The generalization to N=(2,2) supersymmetric theories in 2 spacetime dimensions was proposed by Cumrun Vafa and Nicholas Warner in the November 1988 article Catastrophes and the Classification of Conformal Theories, in this generalization one imposes thatthe superpotential possess a degenerate critical point. The same month, together with Brian Greene they argued that these theories are related by a renormalization group flow to sigma models on Calabi–Yau manifolds in thepaper Calabi–Yau Manifolds and Renormalization Group Flows. In his 1993 paper Phases of N=2 theories intwo-dimensions, Edward Witten argued that Landau–Ginzburg theories and sigma models on Calabi–Yau manifolds are different phases of the same theory. A construction of such a duality was given by relating the Gromov-Witten theory of Calabi-Yau orbifolds to FJRW theory an analogous Landau-Ginzburg "FJRW" theory in The Witten Equation, Mirror Symmetry and Quantum Singularity Theory. Witten's sigma models were later used to describe the low energy dynamics of 4-dimensional gauge theories with monopoles as well as brane constructions. Gaiotto, Gukov & Seiberg (2013)See also[edit]•Domain wall (magnetism)•Flux pinning•Gross–Pitaevskii equation•Husimi Q representation•Landau theory•Magnetic domain•Magnetic flux quantum•Reaction–diffusion systems•Quantum vortex•Topological defectReferences[edit]1.^ Jump up to:a b Ginzburg VL (July 2004). "On superconductivity and superfluidity (what I have and havenot managed to do), as well as on the 'physical minimum' at the beginning of the 21 st century". Chemphyschem.5 (7): 930–945. doi:10.1002/cphc.200400182. PMID15298379.2.Jump up^ Lev D. Landau; Evgeny M. Lifschitz (1984). Electrodynamics of Continuous Media. Course ofTheoretical Physics8. Oxford: Butterworth-Heinemann. ISBN0-7506-2634-8.3.Jump up^ David J. E. Callaway (1990). "On the remarkable structure of the superconductingintermediate state". Nuclear Physics B344 (3): 627–645. Bibcode:1990NuPhB.344..627C.doi:10.1016/0550-3213(90)90672-Z.Papers[edit]•V.L. Ginzburg and L.D. Landau, Zh. Eksp. Teor. Fiz.20, 1064 (1950). English translation in: L. D. Landau, Collected papers (Oxford: Pergamon Press, 1965) p. 546• A.A. Abrikosov, Zh. Eksp. Teor. Fiz.32, 1442 (1957) (English translation: Sov. Phys. JETP5 1174 (1957)].) Abrikosov's original paper on vortex structure of Type-II superconductors derived as a solution of G–L equations for κ > 1/√2•L.P. Gor'kov, Sov. Phys. JETP36, 1364 (1959)• A.A. Abrikosov's 2003 Nobel lecture: pdf file or video•V.L. Ginzburg's 2003 Nobel Lecture: pdf file or video•Gaiotto, David; Gukov, Sergei; Seiberg, Nathan (2013), "Surface Defects and Resolvents" (PDF), Journal of High Energy Physics。
大学生物专业英语教材
大学生物专业英语教材IntroductionThe study of biology is crucial for students majoring in the field of life sciences. As part of their curriculum, college students studying biology are required to have a solid understanding of foundational concepts, theories, and terminology. An essential component of their education is the availability of a comprehensive and informative biology textbook written in English. In this article, we will explore the key features and requirements of an ideal college-level biology textbook for students majoring in biology.Section 1: Content OrganizationA well-designed biology textbook should have a well-structured organization to facilitate effective learning. It is essential to include comprehensive chapters that cover various subject areas within biology, such as cell biology, genetics, ecology, and physiology. Each chapter should provide a clear introduction, followed by in-depth explanations of concepts, supported by relevant examples and illustrations.Moreover, including detailed subheadings within each chapter will allow students to navigate through the textbook effortlessly. The subheadings could cover specific topics, subtopics, or key terms, enhancing the overall readability and making it easier for students to locate information quickly.Section 2: Language and TerminologyConsidering that the textbook caters to English-speaking students studying biology, it is crucial to use clear and concise language. To foster abetter understanding of complex scientific concepts, the textbook should avoid excessive jargon that could hinder comprehension.Throughout the textbook, the accurate usage of scientific terminology is paramount. It is advisable to incorporate a glossary at the end of the book, which provides definitions and explanations for key terms introduced within the text. The glossary will serve as a valuable reference tool, aiding students in grasping the meaning and significance of essential biology terms.Section 3: Visual AidsVisual aids play a pivotal role in enhancing the learning experience for biology students. The textbook should include a variety of visual elements, such as labeled diagrams, illustrations, graphs, and tables, to complement the written text. These visual aids not only break the monotony of continuous text but also enable students to visualize complex biological processes and concepts more effectively.Furthermore, it is essential to ensure that the visual aids are of high quality, clearly labeled, and accompanied by relevant explanations. This will promote a better understanding of the information presented, reinforcing the students' comprehension.Section 4: Practice ExercisesTo reinforce the students' understanding of the material, the textbook should provide ample practice exercises at the end of each chapter. These exercises can include multiple-choice questions, fill-in-the-blank questions, and short answer questions. By engaging in active learning through practiceexercises, students can assess their knowledge and identify areas of weakness that require further review.Additionally, the textbook should include answer keys or solutions to the practice exercises, either within the textbook or as a separate supplementary resource. This will enable self-assessment and facilitate independent learning for students, allowing them to gauge their progress and reinforce their understanding of the subject matter.ConclusionA well-designed biology textbook for college students majoring in biology should incorporate a logical and organized structure, clear language and terminology, visually appealing content, and practical exercises. By catering to the specific needs of biology students, such a textbook will provide the necessary resources for effective and successful learning in the field of biology.。
外语教学理论与实践
11
Language (pp 2-4)
• Language as an outcome of evolution • Read the first paragraph. What is it about? “Pangloss”? • Evolution is not planned, or something directed, but an ad hoc adaptation: one of Nature‟s „odd arrangements and funny solutions‟ (Gould 1990: 20) • Language, for all its obvious wonders, is in many ways like the Panda‟s paw: partly straightforwardly functional, partly dysfunctional, and partly functional in unpredictable ways (Lass 1990).
7
Why do disciplines tend towards separatism?
• Academic enquiry is not only an intellectual matter, but inevitably interwined with personal careers and lives.
一类陈–西蒙斯–薛定谔方程径向对称解的非存在性结论
设 u ( x) ≡ / 0 则称其为非平凡的，否则称为平凡的。 本文考虑 V ( x ) 是正的径向对称的位势且非线性项 g ( u ) = V0 u sin u 这种情形。很明显，此时 g(u)在无 穷远处不是渐近线性的、不是超线性的，也不是次线性的，但有 0 ≤ 的启发，本文的主要结论如下。
g (u ) u ≤ V0 , ∀u ≠ 0 。受[7]和[8]中方法
基金项目
江汉大学 2014 年度大学生创新训练项目 2014yb189。
参考文献 (References)
[1] [2] [3] [4] [5] [6] [7] [8] Dunne, G. (1995) Self-dual Chern-Simons theories. Springer. Jackiw, R. and Pi, S.-Y. (1990) Classical and quantal non-relativistic Chern-Simons theory. Physical Review D, 42, 3500-3513. Jackiw, R. and Pi, S.-Y. (1992) Self-dual Chern-Simons solitons. Progress of Theoretical Physics Supplement, 107, 1-40. Liu, B., Smith, P., Tataru, D. (preprint) Local wellposedness of Chern-Simons-Schrödinger. Byeon, J., Huh, H. and Seok, J. (2012) Standing waves of nonlinear Schrödinger equations with the gauge field. Journal of Functional Analysis, 263, 1575-1608. Huh, H. (2012) Standing waves of the Schrödinger equation coupled with the Chern-Sinons gauge field. Journal of Mathematical Physics, 53, Article ID: 063702. Wan, Y. and Tan, J. (2014) Standing waves for the Chern-Simons-Schrödinger systems without (AR) condition. Journal of Mathematical Analysis and Applications, 415, 422-434. Wang, Z. and Zhou, H. (2007) Positive solution for a nonlinear stationary Schrödinger-Poisson system in R 3 . Discrete and Continuous Dynamical Systems, 18, 809-816.
物理学名词
1/4波片quarter-wave plateCG矢量耦合系数Clebsch-Gordan vector coupling coefficient; 简称“CG[矢耦]系数”。
X射线摄谱仪X-ray spectrographX射线衍射X-ray diffractionX射线衍射仪X-ray diffractometer[玻耳兹曼]H定理[Boltzmann] H-theorem[玻耳兹曼]H函数[Boltzmann] H-function[彻]体力body force[冲]击波shock wave[冲]击波前shock front[狄拉克]δ函数[Dirac] δ-function[第二类]拉格朗日方程Lagrange equation[电]极化强度[electric] polarization[反射]镜mirror[光]谱线spectral line[光]谱仪spectrometer[光]照度illuminance[光学]测角计[optical] goniometer[核]同质异能素[nuclear] isomer[化学]平衡常量[chemical] equilibrium constant[基]元电荷elementary charge[激光]散斑speckle[吉布斯]相律[Gibbs] phase rule[可]变形体deformable body[克劳修斯-]克拉珀龙方程[Clausius-] Clapeyron equation[量子]态[quantum] state[麦克斯韦-]玻耳兹曼分布[Maxwell-]Boltzmann distribution[麦克斯韦-]玻耳兹曼统计法[Maxwell-]Boltzmann statistics[普适]气体常量[universal] gas constant[气]泡室bubble chamber[热]对流[heat] convection[热力学]过程[thermodynamic] process[热力学]力[thermodynamic] force[热力学]流[thermodynamic] flux[热力学]循环[thermodynamic] cycle[事件]间隔interval of events[微观粒子]全同性原理identity principle [of microparticles][物]态参量state parameter, state property[相]互作用interaction[相]互作用绘景interaction picture[相]互作用能interaction energy[旋光]糖量计saccharimeter[指]北极north pole, N pole[指]南极south pole, S pole[主]光轴[principal] optical axis[转动]瞬心instantaneous centre [of rotation][转动]瞬轴instantaneous axis [of rotation]t 分布student's t distributiont 检验student's t testＫ俘获K-captureＳ矩阵S-matrixＷＫＢ近似WKB approximationＸ射线X-rayΓ空间Γ-spaceα粒子α-particleα射线α-rayα衰变α-decayβ射线β-rayβ衰变β-decayγ矩阵γ-matrixγ射线γ-rayγ衰变γ-decayλ相变λ-transitionμ空间μ-spaceχ 分布chi square distributionχ 检验chi square test阿贝不变量Abbe invariant阿贝成象原理Abbe principle of image formation阿贝折射计Abbe refractometer阿贝正弦条件Abbe sine condition阿伏伽德罗常量Avogadro constant阿伏伽德罗定律Avogadro law阿基米德原理Archimedes principle阿特伍德机Atwood machine艾里斑Airy disk爱因斯坦-斯莫卢霍夫斯基理论Einstein-Smoluchowski theory 爱因斯坦场方程Einstein field equation爱因斯坦等效原理Einstein equivalence principle爱因斯坦关系Einstein relation爱因斯坦求和约定Einstein summation convention爱因斯坦同步Einstein synchronization爱因斯坦系数Einstein coefficient安[培]匝数ampere-turns安培[分子电流]假说Ampere hypothesis安培定律Ampere law安培环路定理Ampere circuital theorem安培计ammeter安培力Ampere force安培天平Ampere balance昂萨格倒易关系Onsager reciprocal relation凹面光栅concave grating凹面镜concave mirror凹透镜concave lens奥温电桥Owen bridge巴比涅补偿器Babinet compensator巴耳末系Balmer series白光white light摆pendulum板极plate伴线satellite line半波片halfwave plate半波损失half-wave loss半波天线half-wave antenna半导体semiconductor半导体激光器semiconductor laser半衰期half life period半透[明]膜semi-transparent film半影penumbra半周期带half-period zone傍轴近似paraxial approximation傍轴区paraxial region傍轴条件paraxial condition薄膜干涉film interference薄膜光学film optics薄透镜thin lens保守力conservative force保守系conservative system饱和saturation饱和磁化强度saturation magnetization本底background本体瞬心迹polhode本影umbra本征函数eigenfunction本征频率eigenfrequency本征矢[量] eigenvector本征振荡eigen oscillation本征振动eigenvibration本征值eigenvalue本征值方程eigenvalue equation比长仪comparator比荷specific charge; 又称“荷质比(charge-mass ratio)”。
空调结构件图中的常用英语汇编
结构常用词中英对照（按中文拼音排序）A: 安装支角：Installation supporting angle安装板：Installation board安全认证标签：Safety certificate label按钮开关：Push button switch凹槽：Recess凹面：ConcaveB:白：White扳手：Wrench标签：label摆叶：Flap摆杆组件：Swing link assembly不锈钢螺钉：Stainless steel screw包装纸箱：Packing box包装塑料袋：Packing polyethylene bag变压器：Transformer把手：Handle bar步进电机：Step motor摆叶电机：Flap motor保修证：Warranty玻璃胶带：Fibre glass tapeC: 出风口：air outlet出风栅组件：Air outlet grid穿墙帽：Wall cap粗管连接处：Wide tube connection橙：Orange粗管：Wide tube衬垫：Mat出水管：Drain pipe船形开关：Auto deflector switch槽：Slot侧板组件：Side board assembly传感器固定板：Sensor retaining plate衬板：Backing blockD: 电源单相220V a.c.50 Hz：Power single phase电线孔：Wire bore底板：Chassis挡风板：Windshield导线孔：Conducting wire bore导线紧固组件：Fixed assemble conducting wire导线紧固件：Conducting wire fastener导风窗：Deflector导风板：Air guiding slip导风圈：Air guiding loop导风叶片：Louver blades电线、配管和排水管孔：Bore of wires, tubes and drain hose 电控组件：Electric control assembly电机组件：Motor assembly电机支架：Motor bracket电控盖板组件：Electric control cover assembly电控隔板组件：Electric control baffle assembly电子集尘器：Electronic dust collector电磁四通阀线圈：Electromagnetic 4-way reversing valve coil 电机盖：Electrical motor lid电机座：Electrical motor block底板组件：Chassis assembly带端子导线：Wire with terminal堵水帽：Drain plug垫圈：Washer带垫片螺母：Nut with gasket顶板组件：Upper plate assembly端子座：Terminal base端子盖板：Terminal block cover挡水板：Flashing低压管组件：Low voltage tube assemblyF:粉：Pink复合阀：Compound valve阀芯位置：Spool position防霉过滤网：Anti-mold filter附件袋：Accessories bag风扇罩：Fan housing防护网：Guard screen负离子发生器：Negative ion generator阀门罩：Valve cap风机电容：Fan motor capacitor风门叶片：Louver blades风道导板组件：Guide board of air duct Ass’y风向调节把手：Airflow adjustment lever阀帽：Valve bonnet风扇电机：Fan electromotor风扇电机导线：Lead wire of Fan electromotor服务卡：Service cardG: 高低差7米以下：The value is less than 7m高压管组件：High voltage tube assembly固定面板螺钉：Screws to fix the front board固定吸风栅螺钉：Screws to fix the air inlet grille固定螺栓：Fixed bolt固定夹：Fixed clip管夹：Tube clamp盖板组件：Cover assembly固定板：Fixed plate隔音板：Celotex board (or insulation board, bulkhead) 贯流风扇：Cross-flow fan过热保护器：Overheat protector光再生可除臭过滤网：Photo reversal deodorizing filterH:红：Red黑：Black黄：Yellow灰：Gray后视图：Back view后连接板：Back connecting plate后风道板组件：Back air duct board assembly红镜：Mauve filterHEPA 过滤网：HEPA filter net活性碳清洁滤网：Active carbon filter net后框组件：Rear panel assemblyJ:进风口：air inlet进风门：Ventilator机组间连接电线入口：Connecting wiring inlet for units 接头处：Joint connection接室外机：To outdoor unit接室内机：To indoor unit接信号控制线：To signal control wire接管孔：Junction bore减震橡胶：Cushioning rubber减震圈：Shock absorbing bushing吉祥物标签：Mascot label紧固螺钉：Fixed screw机号标签：Rating label脚支撑板：Anchor chair加强板：Reinforced plate交流接触器：a.c. contactor机制螺钉：Machining screw接地螺钉：Earthing screw净重：Net weight角板：L-barK:空气过滤网：Air filter扩口螺母：Expansion nut开：Open开关膜：Switch film卡钉：Fixed nail卡规：Snap-gauge卡板：CardL:力矩扳手：Torque wrench冷凝器组件：Condenser assembly连杆：Connecting bar离心风扇组件：Centrifugal fan assembly螺钉：Screw六角法兰面螺母：Hexagon flannel bolt冷触媒过滤器：LTC filter冷触媒过滤网（黑）：LTC filter net (black)拉出：Pull螺栓：Bolt螺母：NutM:面板：Front panel面板组件：Front panel assembly毛细管组件：Capillary tube assembly铭牌：Name-plate毛重：Gross weightN: 纳米除臭过滤网：Nano deodorant filter纳米级光触媒：NM-photocatalyst纳米级光触媒脱臭网：NM-photocatalyst deodorant net 内螺纹铜管：Rifled copper tubeP:PVC管：PVC tube配管和排水管孔：Bore of pipes and drain hose配管：PipelinePVC保护带：PVC protective tape排气：Discharge排水软管：Drain hose排水槽组件：Drainage slot Ass’y泡沫衬垫：Foam mat泡沫风道组件：Foam air duct assembly排水管头：Drain elbow joint配管压板：Piping pressure plate配线盖：Wiring lidQ: 墙壁：Wall前连接板：Front connecting plate前风道板组件：Front air duct board assembly曲轴：Crank shaft前导风板组件：Front air guiding panel assembly清洁滤网：Filter net清洁滤网组件：Filter net fittings亲水铝箔：Hydrophilic aluminum finS:室内机配管：Pipeline of indoor unit室内机配管：Pipeline of indoor unit室外机：Outdoor unit塑料胀管：Plastic expansion pipe塑料粘胶带：Plastic adhesive tape上滑轨：Upside slide rail上减震垫：Upside shock pad生物杀菌过滤网：Biological sterilization filter net 四通阀组件：Four-way reversing valve assembly 送风架组件：Air supply shelf Ass’y室内热交换器：Indoor Heat exchangerT: 铜管组件：Copper tube assembly托架组件：Bracket assembly铜管卡箍：Copper tube clip铜管：Copper tube套管：Casing pipe条形码标签：Bar-code label脱臭网：Deodorant filter提手：Handle凸锥：Convex cone凸面：Raised face透光板：Light-directing board调风板组件：Air shutter Ass’y同步电机：Synchronism motor透明胶带：Cellulose tapeW: 微小倾角：Small angle维修口：Service valve维备件：Spare parts for service外框组件：Cabinet assembly外框：Cabinet维修阀：Service valve五金商店；Hardware store温控器：ThermostatX: 向前：Forward向后：Backward向下：Downward向右：Rightward吸风栅：Air inlet grill细管连接处：Narrow tube connection细管：Narrow tube吸气：Suction下滑轨：Downside slide rail旋纽组件：Knot assembly限位卡角：Location limiting angle线夹：Wire clip下减震垫：Downside shock pad小门：Small door销扣：Tab显示窗：Display windowY:压力表：Manometer右视图：Right view右侧板：Right side board压缩机及附件：Compressor and Accessories 遥控器开关：Remote control switch压缩机电容：Compressor capacitor软管加长部分：Hose extension一卷：a rollZ: 障碍物：Blockage自攻螺钉：Tapping bolt至室内控制器：To indoor controller至室外控制器：To outdoor controller真空泵：Vacuum pump左视图：Left view至少：At least蒸发器组件：Evaporator assembly蒸发器固定板：Evaporator retaining plate专用螺栓：Special bolt专用螺母组件：Nut Special assembly专用垫圈：Special washer轴流风扇：Propeller fan遮板：Curtain board左侧板：Left side board轴流风道板：Axial air duct board支撑脚：Support leg (supporter)装箱数量：Loading number轴承：Bearing轴承座：Bearing block中框组件：Medial plate assembly纸胶带：Paper tape包装外表标志中英对照Bottom下端Care小心Don’t cast勿掷Fragile易碎Handle with care小心装卸Haul此处起吊Heave here从此提起Inflammable易燃物Keep dry保持干燥Keep in a cool place在冷处保管Keep in a dry place在干处保管Keep upright勿倒置Not to be tipped勿倾倒To be protected from cold怕冷To be protected from heat怕热Top顶端Use rollers在滚子上移动本机型不提供装箱附件：Installation accessories are not available in this type air conditioner.为避免塑料袋可能带来的危险，请及时抛弃。
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arXiv:hep-th/9411088v2 9 Dec 1994IFUM471/FTROM2F-94/43
October1994
ShockWavesandtheVacuumStructureofGaugeTheories1MaurizioMartelliniDipartimentodiFisicaUniversit`adiMilanoViaCeloria1620133MilanoITALYI.N.F.N.-SezionediPavia
AugustoSagnottiDipartimentodiFisicaUniversit`adiRoma“TorVergata”I.N.F.N.-SezionediRoma“TorVergata”ViadellaRicercaScientifica,100133RomaITALY
MauroZeniDipartimentodiFisicaUniversit`adiMilanoI.N.F.N.-SezionediMilanoViaCeloria1620133MilanoITALY
AbstractInYang-Millstheorymasslesspointsourcesleadnaturallytoshock-waveconfig-urations.Theirmagneticcounterpartsendowthevacuumofthefour-dimensionalcompactabelianmodelwithaCoulomb-gasbehaviourwhosephysicalimplicationsarebrieflydiscussed.Thecurrentsemiclassicalpictureofthevacuumingaugetheoriesrests,toalargeextent,ontheknownsolutionsoftheYang-Millsfieldequations[1].ItiscommonwisdomthatattainingadetailedunderstandingofthisvacuumisamajorchallengeforQuantumFieldTheory,aswellasacrucialstepinassessingitsactualroleinHigh-EnergyPhysics.Inthistalkweconsideraclassofrathersimpleshock-wavesolutionsofthefieldequa-tionswithmasslesspointsources.Inthecompactabeliangaugetheory,theireuclideancounterpartsexhibitratherneatlyaphasetransition[2],thusprovidingasimpleexplicitrealizationofthestandardpicture[3].
LetusbeginbyconsideringtheYang-MillsfieldequationDµFµν=4πjνwiththemasslesspointsourcejaν=qIaδuνδ(u)δ2(r),(1)whereuandvarelight-conecoordinates(u=x0−x32;v=x0+x32),risaspace-likecoordinatevectororthogonaltouandv,andIalabelsthecolorchargeofthepointparticle.Theresultingclassicalsolution,
Aaµ=−2qIaδuµδ(u)logr,(2)whererdenotesthelengthofr,maybeobtainedbyinspection,orbyasimpleextensionofthe“cutandpaste”procedure[4]usedtogenerateasimilartypeofgravitationalwave.Theelectricandmagneticfieldstrengthsassociatedtoeq.(2),
Ei=√r2,(3)
Bi=−√r2(i=1,2),mayalsobeobtainedassingularboostsofastaticCoulombfieldinthelimitwherethevelocityv/c→1[5].The“two-dimensional”shapeoftheshockwaveappliestoarbitrarysuperpositionsofcomovingmasslesspoint-likecurrentsandmaybeascribedtotherelativisticcontractionofthefieldsinthelongitudinaldirection.
Inthequantumtheory,thetopologicalcharacterofthefieldconfigurationspaceplaysacrucialroleindeterminingthenatureofthecorrectdegreesoffreedom.Intheprototypeexampleforthistypeofphenomenon,the2DXYmodel,thefundamentalfieldisanangu-larvariableθ(r)andthenaiveelementaryexcitations,long-wavelengthspinwaves,must
1besupplementedwithgenuinelynewones,vortices.Fromthemathematicalviewpoint,vorticesaresingularfieldconfigurationsthatresultineffective(quantized)violationsofthe“Bianchiidentity”fordθ.TheseexcitationsareresponsiblefortheKosterlitz-Thouless(KT)phasetransition[6]thatseparatestheweakandstrongcouplingregimesofthemodel.
Vorticesareactuallyrelevantinanumberofdifferentmodelswithperiodicfieldcon-figurationspaces,mostnotablyinlatticegaugetheories,wheretheymaybeassociatedwithmagneticmonopoles.Again,incontinuumformulationstheymanifestthemselvesassingularfieldconfigurationsthatviolatetherelevant“Bianchiidentities”.Anumberofreasonscallforaperiodicformulationofabeliangaugetheories,mostnotablythefactthatinunifiedmodelsabeliangaugefieldstypicallyemergefromthespontaneousbreakingofnon-abeliangaugesymmetries[3].
Forcompact3DQEDPolyakov[7]hasshownthattheperiodicityresultsinavacuumfilledwithaplasmaofmonopolesandinamassgapforthegaugefields,aswellasinaconfinementphenomenonatallscales.Forcompact4DQEDaquantitativediscussionoftheroleofvorticeshasbeenhamperedbythestring-likenatureofthecorrespondingexcitations,monopolecurrentloops.Still,thebasicargumentisrathersimple.ItisbestexhibitedstartingfromtheVillain[8]formoftheaction
S=1
2εαβγδFγδ(6)2violatestheBianchiidentityoftheoriginalgaugefield,thecurrentineq.(5)isofmagneticorigin.
Anelegantlatticedescriptionofthismodel,allowingforelectriccurrent(Wilson)loopsaswell,waspresentedin[12].Theresultingpictureinvolvesinteractingmonopoleandchargeloops,butitisdifficulttoturnitintoaquantitativeanalysis,sinceinthiscasetheeffectivesine-Gordondescriptionof3DQED[7]shouldbereplacedbyatheoryofmonopoleloops.Althoughaproperdescriptionofthistheoryislikelytobecomplicated,theintuitiongainedfromordinarystringtheory[9]suggestsapossiblewayofgainingquantitativeinsightintotheproblem.Thismaybeassociatedto“straight”currentloops,andconceivablytomasslessonesnearthephasetransition,thataccordingtonumericalestimatesappearstobeofsecondorder[2].
Intheremainderofthistalkwewouldliketoshowhowthetruncationofthemonopolestringstothese“zeromodes”accountsbothforthephasetransitionandforWilson’sarealaw[11]inaratherneatfashion.Tothisend,weneedthedualsofthefieldsineq.(3).Theymaybederivedfroma“magnetic”analogueofthevectorpotentialofeq.(2)or,alternatively,fromtheordinarypotential