Matter is commonly referred to as the substance of which physical objects are composed. It constitutes the observable Universe. According to the theory of relativity there is no distinction between matter and energy, because matter can be converted to energy (see annihilation), and vice versa (see matter creation). Philosophically, matter constitutes the formless substratum of all things, which exists only potentially and from which reality is produced. In the sense of cont ...

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In physics, it is everything that is constituted of elementary fermions. Matter occupies space and has mass. It is composed predominantly of atoms, which consist of protons, neutrons, and electrons. All gauge bosons (of which the photon is one), which mediate the four fundamental forces, are not considered matter, even though they certainly have energy and some also mass. Matter thus consists of quarks and leptons. There are six types of quarks (strange, charm, top, bottom, up, and down) which combine to form hadrons, primarily baryon ...

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Matter, Matter - Matter in Science

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