Introduction This page focuses on key physics topics for the UPSC Prelims exam, specifically UPSC Prelims Physics GW EVs Graphene. We will cover gravitational waves (GW) as detected by LIGO, electric vehicles (EVs) and the PM E-DRIVE scheme, and the properties and applications of graphene. These areas are crucial for your UPSC Prelims Physics preparation. 1. Elementary Particles and the Standard Model About: Elementary particles are the universe's most fundamental constituents. They are the smallest, indivisible units of matter and energy. The Standard Model of Particle Physics is the overarching theory that classifies these particles and explains their interactions through fundamental forces. Key Points: Elementary particles are the basic building blocks of everything in the universe. They combine to form larger particles, such as protons and neutrons. The Standard Model categorizes these particles into: Quarks: These make up protons and neutrons. Leptons: This group includes electrons. Bosons: These are force-carrying particles. The Standard Model explains three of the four fundamental forces: Electromagnetism: Carried by photons, it governs electric and magnetic fields. Strong Force: Carried by gluons, it binds atomic nuclei together. Weak Force: Carried by W and Z bosons, it's responsible for nuclear reactions like those in stars. Gravity is the fourth fundamental force, but it is not adequately explained by the Standard Model. Recent Developments: The Higgs Boson's discovery at CERN significantly advanced the Standard Model. Impact: The Standard Model is crucial to our understanding of matter and energy, enabling technological and scientific progress. Challenges and Way Forward: A major goal in physics is to develop a "Theory of Everything" that incorporates gravity with the other fundamental forces, addressing the Standard Model's limitations. 2. The Higgs Boson About: The Higgs field is a theoretical field that exists throughout the universe. The Higgs Boson is a particle associated with this field. The Higgs field is crucial because it explains how elementary particles acquire mass. Key Points: Peter Higgs proposed the Higgs field in 1964. Particles gain mass by interacting with the Higgs field. The stronger the interaction, the greater the mass. The Higgs Boson was confirmed experimentally at CERN's Large Hadron Collider in 2012. The Higgs Boson is a type of boson. Properties of the Higgs Boson: Mass: 125.35 GeV Spin: 0 (scalar particle) Short lifetime: It decays rapidly. It is detected by observing the particles it decays into. [caption id="attachment_25999" align="alignnone" width="606"] Higgs Boson[/caption] Timeline: 1964: Peter Higgs proposes the Higgs field. 2012: The Higgs Boson is discovered at CERN. Recent: Nobel Laureate Physicist Peter Higgs passed away. Recent Developments: The death of Peter Higgs is a notable event in the history of physics. Impact: The Higgs Boson's discovery validated the Standard Model and deepened our understanding of mass. Challenges and Way Forward: Research continues at CERN to explore the Higgs Boson's properties and search for new physics beyond the Standard Model. CERN (European Organization for Nuclear Research): Headquarters: Geneva, Switzerland Established: 1954 Objective: International collaboration for high-energy particle physics research. India is an Associate Member. Key Achievements: Discovery of W and Z bosons, invention of the World Wide Web. Its Large Hadron Collider (LHC) is the world's largest particle accelerator. 3. Neutrinos About: Neutrinos are subatomic particles that are electrically neutral and have extremely small mass. They interact weakly with matter, allowing them to pass through it easily. Key Points: Neutrinos have negligible mass and no electric charge. They come in three types or "flavors": electron neutrino, muon neutrino, and tau neutrino. Neutrinos are produced from: Cosmic sources (astrophysical neutrinos) like supernovas and black holes. Nuclear reactions in the Sun. Particle decay in the Earth. Beta decay, particle accelerators, and nuclear power plants. They travel at nearly the speed of light. They travel in straight lines and are not affected by magnetic fields. Recent: The NOVA collaboration in the United States has released new findings on neutrino mass. Recent Developments: New results from the NOVA experiment suggest that there are two lighter neutrinos and one heavier neutrino. . Challenges and Way Forward: Neutrino research is conducted at observatories like: Indian Neutrino Observatory (INO) in Tamil Nadu, funded by the Department of Atomic Energy and the Department of Science and Technology. China's TRIDENT and JUNO. Ice Cube Observatory (the world's largest neutrino observatory). Other Messengers of Celestial Events: Cosmic Rays: Charged particles deflected by magnetic fields. Sources: Neutron stars, pulsars, supernova explosions, black holes, nuclear explosions, lightning. Gamma-Ray Bursts (GRBs): Short bursts of gamma rays, which have the highest energy in the electromagnetic spectrum. Other: Gravitational waves, supernova remnants (SNR), Active Galactic Nuclei (AGN) (e.g., Quasars). Quasars: Quasars are powered by supermassive black holes. They are very luminous. They emit various types of electromagnetic radiation. 4. Gravitational Wave Abouts (GW): Gravitational waves are ripples in spacetime caused by accelerating massive objects. They are a prediction of Einstein's General Theory of Relativity. [caption id="attachment_26000" align="alignnone" width="300"] Gravitational waves[/caption] Key Points: Gravitational waves are created by: Asymmetrical supernova explosions. Orbiting binary stars. Merging black holes. Neutron star mergers. They travel at the speed of light. The first detection of gravitational waves was in 2015 at the Laser Interferometer Gravitational-Wave Observatory (LIGO). LIGO uses interferometers with 4 km long arms to detect gravitational waves. LIGO-India is planned to be built in Maharashtra. Timeline: 1916: Einstein predicts gravitational waves. 2015: First detection of gravitational waves. 2017: Nobel Prize in Physics awarded for the detection of gravitational waves. 2023: Detection of merger GW230529. Recent Developments: A merger between a neutron star and a mystery object (GW230529) was detected in 2023.. This merger involved an object in the "mass gap" between neutron stars and black holes. Impact: Gravitational waves provide new information about the universe. They help us study events like black hole mergers. Other Important Developments Antimatter: Antimatter particles have the same mass as matter particles but opposite charge. When matter and antimatter meet, they annihilate each other. Recent development: Detection of the heaviest antimatter nucleus. High Energy Photon Source (HEPS): China is building HEPS. It will use synchrotron X-rays. Synchrotrons produce intense light beams. India's first synchrotron was Indus-1. Giant Radio Sources (GRS): Indian astronomers discovered 34 new GRSs. GRSs are very large objects with supermassive black holes at their center. These black holes create jets of plasma and radio emissions. The Giant Metrewave Radio Telescope (GMRT) near Pune was used for this discovery. 6. Key Concepts/Terms Brown Dwarf: These are objects between the size of a giant planet and a small star. They don't have enough mass for nuclear fusion. They are called "failed stars." The James Webb Space Telescope (JWST) is used to study them. White Dwarf Star: This is the core of a star that has used up its fuel. There's a limit to how massive a white dwarf can be (Chandrasekhar limit). Recent: A rocky planet was found orbiting a white dwarf. Plunging Region: This is an area around a black hole where matter falls in. Einstein's theory predicts this. Recent: Observational proof of plunging regions. 7. Miscellaneous Nobel Prize in Chemistry 2024 (Protein): Awarded for work on protein design and structure. David Baker: Computational Protein Design (CPD). Demis Hassabis and John Jumper: AlphaFold (protein structure prediction). Proteins are made of amino acids. Proteins have many functions (structural, enzymes, hormones, etc.). Graphene: Graphene is a single layer of carbon atoms. It's very strong, light, and has other unique properties. It has many potential applications (electronics, water filtration, etc.). Recent: India launched the India Graphene Engineering and Innovation Centre (IGEIC). Related: Carbon fiber is another strong material
