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Ordinary Matter and Mass

In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which are made up of interacting subatomic particles. In everyday as well as scientific usage, matter generally includes atoms and anything made up of them, and any particles (or combination of particles) that act as if they have both rest mass and volume. However it does not include massless particles such as photons, or other energy phenomena or waves such as light or heat. Matter exists in various states (also known as phases). These include classical everyday phases such as solid, liquid, and gas – for example water exists as ice, liquid water, and gaseous steam – but other states are possible, including plasma, Bose–Einstein condensates, fermionic condensates, and quark–gluon plasma.

Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a body, until the discovery of the atom and particle physics. It was found that different atoms and different elementary particles, theoretically with the same amount of matter, have nonetheless different masses. Mass in modern physics has multiple definitions which are conceptually distinct, but physically equivalent. Mass can be experimentally defined as a measure of the body's inertia, meaning the resistance to acceleration (change of velocity) when a net force is applied. The object's mass also determines the strength of its gravitational attraction to other bodies.

Matter is a general term describing any physical substance, which is sometimes defined in incompatible ways in different fields of science. Some definitions are based on historical usage from a time when there was no reason to distinguish mass from simply a quantity of matter. By contrast, mass is not a substance but a well-defined, extensive property of matter and other substances or systems. Various types of mass are defined within physics – including rest mass, inertial mass, and relativistic mass.

Visible Energy

In physics, electromagnetic radiation (EMR) is a self-propagating wave of the electromagnetic field that carries momentum and radiant energy through space. It encompasses a broad spectrum, classified by frequency or its inverse, wavelength, ranging from radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. All forms of EMR travel at the speed of light in a vacuum and exhibit wave–particle duality, behaving both as waves and as discrete particles called photons. In quantum mechanics, an alternate way of viewing EMR is that it consists of photons, uncharged elementary particles with zero rest mass which are the quanta of the electromagnetic field, responsible for all electromagnetic interactions. Quantum electrodynamics is the theory of how EMR interacts with matter on an atomic level. Quantum effects provide additional sources of EMR, such as the transition of electrons to lower energy levels in an atom and black-body radiation

Dark Matter

In the early 1990s Astrophysicists verified the existence of Dark Matter, matter that exists in the universe, but we cannot see. This was done by utilizing space telescopes to take a census of the stars and their star type in a galaxy to determine the approximate mass of the galaxy, then measuring the motion of selected stars through the galaxy, then feeding this information into a supercomputer that utilized Einstein’s General Relativity equations to produce a gravitational model of the galaxy. To their surprise, the model said that the Galaxy could not exist because there was insufficient mass to hold it together. They did this for several galaxies, then dozens of galaxies, and every time the computer model said that the Galaxy could not exist.  They adjusted the amount of mass in a galaxy in such a manner as to get the result that agreed with what they were observing in galaxies.  In every case the adjustment was the same – the amount of normal matter (baryonic matter) was 20% of what was needed while 80% of the matter was unseen – which they named “Dark Matter”. The astrophysicists went to the quantum physicists to ask what this Dark Matter could be. The quantum physicists had no answer. Yet everyone agrees that Dark Matter exists, and until the “Standard Model” can incorporate Dark Matter it will be incomplete.

Dark Energy

In the late 1990s Astrophysicists realized it would be possible to measure the rate of expansion of the universe utilizing space telescopes and supercomputers (again utilizing Einstein’s General Relativity equations). At that time they had three scenarios as to the ultimate fate of the universe; a closed universe, an open universe, or a flat universe. A closed universe is one in which the mass of the universe was greater than the force of expansion, and the universe would collapse onto itself to create a new universe (the expansion of space, a stop, and then the contraction of space). An open universe is one that the expansion is greater than the mass and the universe will expand forever and eventually suffer total radioactive decay and cease to exist. A flat universe is one in which the mass and the expansion are equal, and the universe would just stop and be fixed in size (nobody expected this result, but it was possible mathematically). Everybody expected that the rate of expansion was slowing, and we would end up in either an open or closed universe. To their surprise, the results showed that the rate of expansion was increasing. The only way this would be possible if there were a repulsive energy force that was greater than the gravitational force. They named this energy “Dark Energy”. The astrophysicists went to the quantum physicists to ask what this Dark Energy could be. The quantum physicists had no answer. Yet everyone agrees that Dark Energy exists, and until the “Standard Model” can incorporate Dark Energy it will be incomplete.