Marco Azimonti Personal Blog

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Euler's formula in complex analysis

In this blog post, I explain Euler's formula and its significance in connecting exponential and trigonometric functions in the complex plane. By using Maclaurin series expansions, I derive the celebrated result and discuss its geometric interpretation as a parametrization of the unit circle in the complex plane. I highlight its applications in expressing complex numbers in polar form and demonstrate how De Moivre's formula follows naturally. Euler's formula not only simplifies calculations in mathematics and engineering but also provides valuable insight into the nature of analytic functions.

Complex numbers: representation and algebra

In this blog post, I present a concise overview of complex numbers, beginning with their algebraic definition, notation, and the introduction of the imaginary unit. I discuss how complex numbers relate to points and vectors in the complex plane, explain the geometric significance of addition and multiplication, and cover basic arithmetic operations in both Cartesian and polar coordinates. The article treats the modulus and argument, introduces Euler's formula, and clarifies the concept of complex conjugates with their key properties and applications in simplifying expressions involving complex numbers.

Lagrange multipliers: pendulum

In this blog post, I illustrate how Lagrange multipliers can be applied to determine constraint forces in classical mechanics. I use the example of a simple pendulum with a fixed length to show how holonomic constraints are incorporated into the Lagrangian formalism, and how the multiplier emerges naturally as the force needed to maintain the length constraint. I derive the equations of motion using the extended Lagrangian, interpret the meaning of the Lagrange multiplier, and explicitly recover the familiar expression for the tension in the pendulum.

Lagrange multipliers: catenary

In this blog post, I show how a chain suspended between two points takes on the form of a catenary, governed not by a parabola but by a hyperbolic cosine. I derive the shape by minimizing the potential energy with a constraint on chain length, using the calculus of variations. The result is a clear connection between physical principles and the famous catenary equation. I also explain how the horizontal tension appears as an integration constant, reflecting the mechanics of the system.

Lagrange multipliers: cylinder on an incline

In this blog post, I present the principle of least action as an alternative framework to Newtonian mechanics, outlining how it leads to Lagrange's equations of motion when applied to systems with generalized coordinates. I show how considering small variations in a path yields the equations of motion by demanding the action be stationary. The method also handles systems with constraints efficiently through Lagrange multipliers, enabling independent variations of coordinates. This approach greatly simplifies the analysis of mechanical problems while maintaining full generality.

From simple to chaotic: various pendulum dynamics

This article provides a coder's perspective on implementing various pendulum simulations in JavaScript. We'll examine how each system, from the classic simple pendulum to the chaotic double pendulum, is modeled, how their differential equations are translated into code for numerical integration, and how their unique parameters are exposed through dynamic UI controls.

Architecting an interactive web-based pendulum simulation platform

This post delves into the coding architecture of a web-based platform designed for interactive pendulum simulations. We'll explore the modular JavaScript structure, the role of the HTML5 Canvas for rendering, and how dynamic user controls are managed to create an extensible environment for visualizing classical mechanics.

Pendulum simulations: exploring classic and chaotic motion

In this blog post, I present a collection of interactive physics simulations focused on various pendulum systems. I explore the classic simple pendulum and its non-linear dynamics, extend the model with damping and periodic driving, and demonstrate the isochronous property of the cycloidal pendulum. I also simulate an elastic spring pendulum with coupled degrees of freedom and the double pendulum, a standard system exhibiting chaos. Each example allows for parameter adjustments and real-time visualization, providing clear insight into the underlying mechanics and the diverse behaviors resulting from different physical influences.

[LinkedIn投稿] ホイヘンス サイクロイド 振り子

このブログ記事では、1673年にクリスティアーン・ホイヘンスが考案した独創的な発明であるサイクロイド振り子の魅力的な世界を掘り下げます。その重要な特性である等時性、つまり振幅に関係なく振動周期が一定に保たれるという、正確な時計にとって不可欠な特徴について探求します。このユニークな挙動を示す基礎となるラグランジュ力学を説明し、数学的な導出を提供します。さらに、異なる初期条件を持つ5つの振り子がすべて見事に同じ周期で振動する様子を示す私のPythonシミュレーションを紹介します。

[LinkedIn post] Pendolo Cicloidale

In questo post del blog, approfondisco l'affascinante mondo del pendolo cicloidale, un'invenzione di Christiaan Huygens del 1673. Esploro la sua proprietà chiave - l'isocronismo - per cui il periodo di oscillazione rimane costante indipendentemente dall'ampiezza, una caratteristica cruciale per orologi precisi. Spiego la meccanica lagrangiana sottostante e fornisco la derivazione matematica che dimostra questo comportamento unico. Inoltre, presento la mia simulazione Python che mostra cinque pendoli con diverse condizioni iniziali, tutti oscillanti in modo impressionante con lo stesso identico periodo.

[LinkedIn post] Cycloidal Pendulum

In this blog post, I analyze the cycloidal pendulum, an invention by Christiaan Huygens from 1673. I explore its key property - isochronism - where the oscillation period remains constant regardless of amplitude, a important feature for accurate clocks. I explain the underlying Lagrangian mechanics and provide the mathematical derivation that demonstrates this unique behavior. Furthermore, I present my Python simulation showcasing five pendulums with different initial conditions, all impressively swinging with the exact same period.

Lagrangian mechanics example: Cycloidal pendulum

In this blog post, I explore Christiaan Huygens' discovery of the cycloidal pendulum, which achieves isochronism by guiding the bob along an inverted cycloidal path. Using Lagrangian mechanics, I show how the constraint transforms the equation of motion into that of a simple harmonic oscillator, resulting in a period that remains constant regardless of amplitude.

Lagrange multipliers: holonomic constraints

In this blog post, I explore how Lagrange multipliers are used within Lagrangian mechanics to manage holonomic constraints directly at the equation level. I construct the augmented Lagrangian, introduce time-dependent multipliers, and show how they modify the Euler-Lagrange equations to account for constraint forces explicitly. I explain how the resulting differential-algebraic system describes the dynamics of both the coordinates and the multipliers, and I illustrate how the multipliers relate to the physical forces necessary to enforce the constraints in the system.

Lagrange multipliers: constrained optimization

In this blog post, I introduce the method of Lagrange multipliers for solving constrained optimization problems in both finite and infinite dimensions. I cover the mathematical formulation for functions with equality constraints and illustrate how the same principle extends to functionals, especially when dealing with variational problems. With a clear and direct exposition, I show the connection between gradients and multipliers, and the use of the Euler-Lagrange equation in the presence of integral constraints, providing a mathematically rigorous perspective throughout.

The principle of least action

In this blog post, I present the principle of least action as an alternative framework to Newtonian mechanics, outlining how it leads to Lagrange's equations of motion when applied to systems with generalized coordinates. I show how considering small variations in a path yields the equations of motion by demanding the action be stationary. The method also handles systems with constraints efficiently through Lagrange multipliers, enabling independent variations of coordinates. This approach greatly simplifies the analysis of mechanical problems while maintaining full generality.

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