Explore the World of Physics

An Overview of Physics: History, Philosophy, and Core Theories

Physics is the natural science of matter and energy, studying its fundamental constituents, motion, behavior through space and time, and related entities of energy and force.
The main goal of physics is to understand how the universe behaves, and it is one of the oldest academic disciplines.
Physics intersects with many interdisciplinary areas of research and often enables advances in new technologies.
Ancient astronomy, such as the Sumerians and Egyptians, had predictive knowledge and a basic awareness of the motions of celestial bodies, which laid the foundation for later astronomy.
Natural philosophy, with its origins in Greece, rejected non-naturalistic explanations for natural phenomena and proposed ideas verified by reason and observation.
Medieval European and Islamic scholars inherited Aristotelian physics and developed it further, especially emphasizing observation and the scientific method.
Classical physics became a separate science when early modern Europeans used experimental and quantitative methods to discover what are now considered to be the laws of physics.
Major developments in this period include the replacement of the geocentric model of the Solar System with the heliocentric Copernican model, Kepler's laws, Galileo's pioneering work on telescopes, and Newton's discovery and unification of the laws of motion and universal gravitation.
Modern physics began in the early 20th century with the work of Max Planck in quantum theory and Albert Einstein's theory of relativity, correcting inaccuracies in classical mechanics in certain situations.
The Standard Model of particle physics was derived from early work, and physics beyond the Standard Model, with theories such as supersymmetry, is an active area of research.
Physics relies on philosophy of science and its "scientific method" to advance our knowledge of the physical world, involving issues such as the nature of space and time, determinism, empiricism, naturalism, and realism.
Core theories of physics include classical mechanics, quantum mechanics, thermodynamics and statistical mechanics, electromagnetism, and special relativity, and any physicist is expected to be literate in them.Overview of Physics: Fields, Theories, and Applications
Physics encompasses the study of matter, energy, and their interactions, and is divided into several branches, including classical mechanics, acoustics, optics, thermodynamics, electricity and magnetism, and quantum mechanics.
Classical mechanics deals with forces and motion, while acoustics studies sound and its properties. Optics focuses on the behavior of light, and thermodynamics explores the relationships between heat and other forms of energy.
Electricity and magnetism are studied together and are concerned with the behavior of electric charges and magnetic fields. Modern physics explores matter and energy on a very small or very large scale, such as the behavior of particles in particle accelerators.
Physics uses mathematics to describe and formulate experimental results, and the laws of physics are considered universal and do not change with time.
Applied physics is used to develop new technologies or solve problems, such as in engineering, medicine, and forensic investigations.
Physicists use the scientific method to test the validity of theories and often work at the interplay of theory and experiment.
Physics aims to describe the various phenomena that occur in nature in terms of simpler phenomena and to find an ultimate reason for why nature is as it is.
Contemporary research in physics is divided into several fields, including nuclear and particle physics, condensed matter physics, atomic, molecular, and optical physics, astrophysics, and applied physics.
Particle physics studies the elementary constituents of matter and energy and their interactions, while nuclear physics studies the constituents and interactions of atomic nuclei.
Atomic, molecular, and optical physics studies the interactions between matter and light on the scale of single atoms and molecules.
Condensed matter physics focuses on the macroscopic physical properties of matter, such as the behavior of solids and liquids.
Physics is a fundamental science that influences many other fields, including chemistry, astronomy, geology, biology, and engineering.Overview of Physics and its Subfields
Condensed matter physics deals with the bonding of particles in large systems, such as solids and liquids, and includes fields like solid-state physics, chemistry, and materials science.
Astrophysics applies physics to the study of celestial bodies and phenomena, using many disciplines like mechanics, thermodynamics, and quantum mechanics.
Physical cosmology studies the formation and evolution of the universe, including the Big Bang theory and the ΛCDM model.
The Fermi Gamma-ray Space Telescope and IBEX are currently being used to study dark matter and other astrophysical phenomena.
Research in physics is ongoing in many areas, including condensed matter physics, particle physics, and the study of dark matter and dark energy.
High-temperature superconductivity and the understanding of complex phenomena are among the unsolved theoretical problems in physics.
Neutrinos have been found to have non-zero mass, and research aims to prove or disprove supersymmetry.
The Large Hadron Collider has already found the Higgs boson and continues to conduct research.
Physics has many interdisciplinary applications, such as turbulence in aerodynamics and pattern formation in biological systems.
Physics has many subfields, including condensed matter physics, astrophysics, physical cosmology, particle physics, and complex systems.
Physics has a large overlap with other fields, including chemistry, materials science, nanotechnology, and engineering.
Physics education and careers are important for the advancement of science and technology.