Author: Tru Physics

  • Gravitational Waves

    Introduction Gravitational waves are ripples in the fabric of spacetime caused by some of the most violent and energetic processes in the Universe. Albert Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity. Basics of Gravitational Waves Gravitational waves are distortions in spacetime that propagate as waves, emanating from…

  • Gravitational Lensing

    Introduction Gravitational lensing is a phenomenon that occurs when a huge mass creates a gravitational field that distorts and focuses light passing near it. This effect was first predicted by Albert Einstein’s General Theory of Relativity and has since been confirmed by multiple observations. Basics of Gravitational Lensing According to General Relativity, a mass curves…

  • Gravitational Force

    Introduction The gravitational force is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward one another. It is one of the four fundamental forces known in nature. Newton’s Law of Universal Gravitation In the 17th century, Sir Isaac Newton proposed his Law of Universal Gravitation,…

  • General Relativity

    Introduction General Relativity is a theory of gravitation that was developed by Albert Einstein between 1907 and 1915. Based on his idea of what he called “The Equivalence Principle,” he proposed that gravity is not a force in the traditional sense, but a curvature in spacetime caused by mass and energy. The Field Equations The…

  • Geiger-Marsden Experiment

    Introduction The Geiger-Marsden experiment, also known as the Gold Foil experiment or the Rutherford experiment, was an experiment conducted by Hans Geiger and Ernest Marsden under the direction of Ernest Rutherford in the early 20th century. It drastically improved our understanding of atomic structure. The Experiment The experiment involved firing a stream of alpha particles,…

  • Fourier Transform

    Introduction The Fourier transform is a mathematical technique used in a wide range of fields including physics, engineering, and signal processing. It decomposes a function or a signal into its constituent frequencies, revealing the frequency spectrum of the signal. Basic Definition For a function , the Fourier transform is defined as: Here represents a complex…

  • Fiber Optics

    Introduction Fiber optics refers to the technology of transmitting information as pulses of light through strands of fiber made from glass or plastic. It’s a key technology in telecommunications, enabling long-distance and high-speed data transmission. Basic Principles The fundamental principle behind fiber optics is total internal reflection. When light traveling through a medium hits a…

  • Feynman Diagrams

    Introduction Feynman diagrams are graphical representations used in quantum field theory to describe and calculate the behavior of subatomic particles. Named after their creator, physicist Richard Feynman, these diagrams provide a way to pictorially encode the mathematical expressions governing the interactions between particles. Basic Components A Feynman diagram consists of lines and vertices. Lines represent…

  • Fermi Surface

    Introduction The Fermi Surface is a concept in quantum mechanics, particularly in the field of condensed matter physics. It is the surface in reciprocal space (momentum space) which separates occupied from unoccupied electron energy states at absolute zero temperature. Defining the Fermi Surface In a solid, the energy states of electrons, particularly those near the…

  • Fermi Paradox

    Introduction The Fermi Paradox is a question originally posed by physicists Enrico Fermi and Michael Hart. The paradox arises from the high probability estimates for the existence of extraterrestrial life, such as those provided by the Drake Equation, and the lack of evidence or contact with such civilizations. The Paradox The basic form of the…