"For [...] small things, there must be something else. There is. We call it the electric interaction (more generally, the electromagnetic interaction), and it arises from an endowment of matter known as the electric charge. Standing still, an electrically charged particle throws up an electric potential to which other charged particles can respond.Electric or magnetic, charge gives rise to both. Whether we say 'electric potential' (because we perceive a charge to be at rest) or "magnetic potential" (because we perceive a charge to be in motion), the difference lies solely in our point of view. The source is one. From the world of mass we descend [...] into the world of charge, ready to see our most familiar surroundings in a new light. Let there be electric charge." (Michael Munowitz, "Knowing: The Nature of Physical Law", 2005)
"We divide math up into separate areas (analysis, mechanics, algebra, geometry, electromagnetism, number theory, quantum mechanics, etc.) to clarify the study of each part; but the equally valuable activity of integrating the components into a working whole is all too often neglected. Without it, the stated aim of ‘taking something apart to see how it ticks’ degenerates imperceptibly into ‘taking it apart to ensure it never ticks again’." (Miles Reid & Balazs Szendröi, "Geometry and Topology", 2005)
"In formal terms, the ground state energy (vacuum energy) of the electromagnetic quantum field is infinite. This causes mathematical trouble in quantum electrodynamics." Eberhard Zeidler, "Quantum Field Theory II: Quantum Electrodynamics", 2006)
"Topology is rooted in Maxwell’s theory on the electromagnetic field." (Eberhard Zeidler, "Quantum Field Theory I: Basics in Mathematics and Physics", 2006)
"In a Newtonian view, space and time are separate and different. Symmetries of the laws of physics are combinations of rigid motions of space and an independent shift in time. But... these transformations do not leave Maxwell's equations invariant. Pondering this, the mathematicians Henri Poincaré and Hermann Minkowski were led to a new view of the symmetries of space and time, on a purely mathematical level. If they had described these symmetries in physical terms, they would have beaten Einstein to relativity, but they avoided physical speculations. They did understand that symmetries in the laws of electromagnetism do not affect space and time independently but mix them up. The mathematical scheme describing these intertwined changes is known as the Lorentz group, after the physicist, Hendrik Lorentz." (Ian Stewart, "Why Beauty Is Truth: The History of Symmetry", 2008)
"The abstractions of Einstein's curved space and time gave rise to analogies and pictures that played a new explanatory role. Space and time gave way to space-time, visible light was augmented by images across the rest of the electromagnetic spectrum, and we realise d that we could see back towards the apparent beginnings of time." (John D Barrow,"Cosmic Imagery: Key Images in the History of Science", 2008)
"There’s matter, like the electron; antimatter, like the positron; and then there are things that are neither matter nor antimatter. The most familiar example of something that is beyond substance is electromagnetic radiation. All electromagnetic radiation, from gamma rays through X-rays and ultra-violet to visible light, infra red, and radio waves, consists of photons of different energies. Matter and antimatter can cancel one another out, their annihilation leaving non-substance in the form of photons; if the conditions are right this sequence can happen in reverse where photons turn into pieces of matter and antimatter." (Frank Close, "Antimatter", 2009)
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