what is a point particle?
364720
point particle is an idealized particle heavily used in physics. Its distinguishing features are that it does not have any volume or surface area; it is zero dimensional. A point particle is often a good approximation of real particles and also more extended bodies. In Newtonian gravitation as well as General relativity and Electromagnetism, the respective fields outside of a spherical object are identical to those of a point particle of equal charge/mass located at the center of the sphere.\n\nParticle physics suggests that fundamental particles (quarks, electrons and other leptons) may be point particles which can contain mass, charge, spin, and multipole moments without occupying any volume
801276
Light is a particle. Wave is its function.
154188
Any of a group of six elementary particles having electric charges of a magnitude one-third or two-thirds that of the electron, regarded as constituents of all hadrons.\n\n\nA soft creamy acid-cured cheese of central Europe made from whole milk.\n\n\nhypothetical truly fundamental particle in mesons and baryons; there are supposed to be six flavors of quarks (and their antiquarks), which come in pairs; each has an electric charge of +2/3 or -1/3 2: fresh unripened cheese of a smooth texture made from pasteurized milk, a starter, and rennet.
479672
zero point energy comes from the fact that by heisenberg's uncertainty principle you can never know exactly the momentum (speed) and location of a particle at the same time. of course the uncertainty is only on the atomic scale, so you can be pretty sure you are in front of your computer with 0 velocity right now. this uncertainty comes from the fact that measuring a particle will change it - you have to bounce photons (light) off of it, and just like bouncing one ball off another, it makes both go in different directions. at the atomic level, however you can't predict which way they'll go very well. now, to get back to zero point energy, this means that any bound particle - one which is stuck in a certain position, like an electron stuck orbiting a nucleus - has a known position. if it had no energy, we would know its location and its velocity - 0. thus, its minimum energy is greater than 0. i don't really know why people would think this has to do with God, but i'll take a shot. they might say that this nonzero energy shows God's presence everywhere, that God is a positive force keeping everything moving. or maybe its some intelligent design argument.  as always, check wikipedia.org
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Center of gravity is not a point but is a line of action of force...\nSince a line is of infinite lenght there is no way you can think of the center of gravity of an object which does not pass through the object.\n\nhttp://www.schoolingkids.com/\n\nhttp://www.futureaccountant.com/
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Absolutely.\n\nThe terms "point," "plane," "straight line," and so forth are arbitrary terms used in mathematics. \nIn reality, the exact position of a point is completely dependent on the observer and his reference. A "starting point" will never match the "ending point" for all references after a certain amount of time has passed.\nRemember, there is no reference that is perfectly at rest relative to all other references - yet each will legitimately consider its own reference as stationary.
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A more generic term for the components of an atom is "sub-atomic particles."  I think that's the answer you're looking for.
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a very small piece of styrofoam in the middle represents the nucleaus. it should consist of one proton and a different colored neutron. then, have a lot of space then put in a cirle around the center one styrofoam ball representing an electron.
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(1) there is no problem with the concept\n\n(2) the concept refers not to "a wave of particle". But to the fact that the wave IS the particle, and the particle IS the wave.  More precisely, the particle (in our everyday definition, i.e. a small bit of matter) does not really exist at a precise point in space, but it is to be found in a given region, and the probability of finding it there is proportional to the absolute value of its "wave function"\n\nyou seem to view this as little bits of matter / light undulating on top of a wave - that's wrong.\n\n\nhistorically, what happened is that various experiments seemed to suggest that SOMETIMES it seemed that you had a wave, and other times, a particle.\n\nThe most famous one is the double slot experiment.  Incoming light will go through the two slots, and lights re-emitted after having gone through each slot will interfere with each other, and on a screen you will observe an interference pattern, i.e. a series of bright and dark bands.\n\nso then someone suggested to use light of such low intensity so that you'd literally emit one photon at a time.  Hoping to not get any interference picture - since each photon could not interfere with anything.\n\nbut what happened was that the photons would arrive at various points on the screen, and little by little, their accumulation would reconstruct the interference picture\n\nthis is what caused people problems - until they invested quantum physics, which deals perfectly with this.
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Impossible.  There's no layman's equivalent to the concept of an object with no radius (true point) having angular momentum.  Nuclear particles have electromagnetic radii, but their mass is not distributed over that spherical area, so gravitationally subatomic particles are true points)  \n\nNot only that, but instead of having a continuum of possible momenta, subatomic particles can only have a small number of precise momenta (hence the "quantum" in quantum physics)\n\nSo you need to picture a point in space that behaves like it's spinning around a center of gravity, but it has no center of gravity because it has no radius.  And it spins at three speeds: -1, 0, and 1.  (some particles are + and - 1/2)  But there's no in between, and transitions are literally instant. \n\nThe bottom line is, what makes quantum physics so difficult conceptually is that it has very little to do with the physical world we are used to.  The rules are completely 100% different at that small of a scale, and since we will never be able to shrink down to that level to actually see it, all we can do is describe our observations mathematically.  But there's no way to accurately depict this stuff visually because it's like nothing we've ever seen or will ever be able to see.\n\nIt's the mystery of the quantum universe!
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Quantum mechanics is the wave particle duality.  \n\nQuantum mechanics defines particles as waves that are governed by the schodinger wave equation.  (or Dirac equation)\n\none of the results of quantum mechanics is that if you define a particle to exist at a single point then in a few moments it will begin to spread out in to a wave such that it exists over a small volume.\n\n\nNote added after seeing the answer below... \n\nThe Heisenberg Uncertanty Principle is found as a consequence of quantum theory
1933
One property of matter is the electric charge. Most sub-atomic particles have either a positive (+) or negative (-) electrical charge. Those that don't are considered neutral. The most common charged particles are the electron and proton. Atoms with an excess of electrons are called negative ions. Those with missing electrons are called positive ions. There is an electrical field that flows between opposite charges, causing an electrical force. This results in an attractive force between the opposite charges and a repelling force between like charges.
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Ball and stick - Ball is the atom, stick is the bond to another atom. It's the typcial model one would normally see.\n\nSpace-Filling - Essentially Balls touching eachother, sharing electrons (that's the bond). Best visual of this may be if you imagine a 3D Image of the Olympic Rings. Unlike the Ball and stick model, the space between the atoms is "Filled"
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what an introduction to a simple point
161235
A graviton is the name. The existance of this particle has´n´t been confirmed yet but hopefully it will be soon.
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By using particle collisions, it is possible to show that there is *something* inside of protons, for example. These 'somethings' have the properties that the theorists predict that quarks will have. Furthermore, the theoretical predictions made by the quark models (such as decay rates, reaction cross sections, etc) are in agreement with what is actually seen in the accelerators. This is why we say that quarks exist even though nobody has seen an isolated quark (and there are good theoretical reasons why we may never see one).\n\nOn the other hand, the strings in string theory are *incredibly* small, which means we need very high energies to probe them. No particle accelerator that we have right now will produce these energies. Also, the strings are what would describe the nature of the quarks, not show they don't exist. The question is whether they are point particles or extended to some (small!) degree.
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In some sense, it could be made up of individual particles.  But if you break down the particles far enough, they start to take on properties of waves as well as particles.  But the question is, if they are waves, what is there to do the waving?\n\nIf we observe the particles very closely, we can determine their exact positions - but the more precisely we determine their positions, the less we know about their momentum!  We can only draw a graph to represent the probability of a given particle's momentum _if_ it happened to be at a particular position, and there does not seem to be any way to exactly predict what its position or momentum might be at any given point in time, without measuring it.\n\nSo it could be that matter does not exist at all, unless it is being measured, or observed.  Could it be that what matter is made up of is...mind?