Posted on Categories:Electromagnetism, 物理代写, 电磁学

物理代写|电磁学代写Electromagnetism代考|PHY340 Poisson Bracket Method

avatest™

avatest™帮您通过考试

avatest™的各个学科专家已帮了学生顺利通过达上千场考试。我们保证您快速准时完成各时长和类型的考试，包括in class、take home、online、proctor。写手整理各样的资源来或按照您学校的资料教您，创造模拟试题，提供所有的问题例子，以保证您在真实考试中取得的通过率是85%以上。如果您有即将到来的每周、季考、期中或期末考试，我们都能帮助您！

•最快12小时交付

•200+ 英语母语导师

•70分以下全额退款

物理代写|电磁学代写Electromagnetism代考|Poisson Bracket Method

In this section we give a detailed treatment of the fields based on the use of the Poisson brackets. The main motivation for the presentation of this method, widely used in classical mechanics, is that it provides the starting point for the quantization of the fields and the quantum theory of radiation.
Consider a set of generalized coordinates $q_{s}$ and momenta $p_{s}$. Let
$$H=H\left(p_{s}, q_{s}, t\right)$$
be the Hamiltonian of the system. A Poisson bracket of two quantities $F$ and $G$ is defined as follows:
$${F, G}=\sum_{s}\left(\frac{\partial F}{\partial p_{s}} \frac{\partial G}{\partial q_{s}}-\frac{\partial F}{\partial q_{s}} \frac{\partial G}{\partial p_{s}}\right)$$
The Poisson brackets have the following properties

(1)
\begin{aligned} &\left{p_{s}, q_{t}\right}=\delta_{s t} \ &\left{p_{s}, p_{t}\right}=\left{q_{s}, q_{t}\right}=0 \end{aligned}
(2)
$$\left{F_{1} F_{2}, G\right}=F_{1}\left{F_{2}, G\right}+F_{2}\left{F_{1}, G\right}$$

物理代写|电磁学代写Electromagnetism代考|Hamiltonian of a Closed System

We have discussed until now open systems, covering:
(1) The motion of particles in given fields
(2) The Hamiltonian of the A field.
We want now to write the Hamiltonian that is applicable to be closed system. A closed system is a set of charged particles (generic mass $=m_{s}$, generic charge $=e_{s}$ ) plus the fields that they produce.

We can go from a closed system to an open system under certain circumstances. Consider the closed system $A+B$ in Fig. 11.3. The part $B$ is an open system if we can take into account the presence of $A$ only by means of a field produced by $A$ on $B$; this can be done if the reactions of $B$ on $A$ are negligible.

When we use a power supply to energize a system, we can consider the system “open” if we can disregard its reaction on the power supply. A single atom or a single molecule in the absence of any external field is an example of a closed system.

物理代写|电磁学代写Electromagnetism代考|Poisson Bracket Method

$$H=H\left(p_{s}, q_{s}, t\right)$$

$$F, G=\sum_{s}\left(\frac{\partial F}{\partial p_{s}} \frac{\partial G}{\partial q_{s}}-\frac{\partial F}{\partial q_{s}} \frac{\partial G}{\partial p_{s}}\right)$$

(1)
lleft 的分隔符竾失或无法识别
(2)
lleft 的分隔符缺失或无法识别

物理代写|电磁学代写Electromagnetism代考|Hamiltonian of a Closed System

(1) 给定场中粒子的运动
(2) $A$ 场的哈密顿量。

MATLAB代写

MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。