How physics breaks down in a black hole

One of the most cherished laws of physics—the conservation of charge—has come under fire in "startling" research by physicists.

Bending light for safer driving; invisibility cloaks to come?

Optical cloaking allows objects to be hidden in plain sight or to become invisible by guiding light around anything placed inside the cloak. While cloaking has been popularized in fiction, like in the "Harry Potter" books, ...

Insulators turn up the heat on quantum bits

Physicists have long suspected that dielectric materials may significantly disrupt ion-trap quantum computers. Now, researchers led by Tracy Northup have developed a new method to quantify this source of error for the first ...

Electromagnetic anomalies that occur before an earthquake

It has been documented over hundreds of years that various electromagnetic anomalies occur a few weeks before the occurrence of a large earthquake. These electromagnetic anomalies are variations that appear in telluric current, ...

NASA rocket mission studying escaping radio waves

A NASA rocket mission, launching May 26, 2021, will study radio waves that escape through the Earth's ionosphere impacting the environment surrounding GPS and geosynchronous satellites, such as those for weather monitoring ...

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Electromagnetism is one of the four fundamental interactions in nature. The other three are the strong interaction, the weak interaction and gravitation. Electromagnetism is the force that causes the interaction between electrically charged particles; the areas in which this happens are called electromagnetic fields.

Electromagnetism is responsible for practically all the phenomena encountered in daily life, with the exception of gravity. Ordinary matter takes its form as a result of intermolecular forces between individual molecules in matter. Electromagnetism is also the force which attracts electrons to an atomic nucleus to form atoms, which are the building blocks of molecules. This governs the processes involved in chemistry, which arise from interactions between the electrons of neighboring atoms.

Electromagnetism manifests as both electric fields and magnetic fields. Both fields are simply different aspects of electromagnetism, and hence are intrinsically related. Thus, a changing electric field generates a magnetic field; conversely a changing magnetic field generates an electric field. This effect is called electromagnetic induction, and is the basis of operation for electrical generators, induction motors, and transformers. Mathematically speaking, magnetic fields and electric fields are convertible with relative motion as a four vector.

Electric fields are the cause of several common phenomena, such as electric potential (such as the voltage of a battery) and electric current (such as the flow of electricity through a flashlight). Magnetic fields are the cause of the force associated with magnets.

In quantum electrodynamics, electromagnetic interactions between charged particles can be calculated using the method of Feynman diagrams, in which we picture messenger particles called virtual photons being exchanged between charged particles. This method can be derived from the field picture through perturbation theory.

The theoretical implications of electromagnetism led to the development of special relativity by Albert Einstein in 1905.

This text uses material from Wikipedia, licensed under CC BY-SA