What is Matter: Definition and 1000 Discussions

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, and 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. 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.Usually atoms can be imagined as a nucleus of protons and neutrons, and a surrounding "cloud" of orbiting electrons which "take up space". However this is only somewhat correct, because subatomic particles and their properties are governed by their quantum nature, which means they do not act as everyday objects appear to act – they can act like waves as well as particles and they do not have well-defined sizes or positions. In the Standard Model of particle physics, matter is not a fundamental concept because the elementary constituents of atoms are quantum entities which do not have an inherent "size" or "volume" in any everyday sense of the word. Due to the exclusion principle and other fundamental interactions, some "point particles" known as fermions (quarks, leptons), and many composites and atoms, are effectively forced to keep a distance from other particles under everyday conditions; this creates the property of matter which appears to us as matter taking up space.
For much of the history of the natural sciences people have contemplated the exact nature of matter. The idea that matter was built of discrete building blocks, the so-called particulate theory of matter, independently appeared in ancient Greece and ancient India among Buddhists, Hindus and Jains in 1st-millennium BC. Ancient philosophers who proposed the particulate theory of matter include Kanada (c. 6th–century BC or after), Leucippus (~490 BC) and Democritus (~470–380 BC).

View More On Wikipedia.org
  1. D

    Kinetic energy loss in disintegrated matter

    What happens to the kinetic energy when an object is disintegrated? Does it survive? For example, if I throw a baseball at the sun at 100 mph, I will get X amounts of heat energy released and X amount of light as it burned up before contact. If I threw another baseball 100,000 mph into the sun...
  2. O

    I Creation of matter in the big bang

    Hi, http://curious.astro.cornell.edu/about-us/101-the-universe/cosmology-and-the-big-bang/general-questions/570-where-did-the-matter-in-the-universe-come-from-intermediate The website given above says that the matter was created via pair production process (like electron anti-electron...
  3. A

    A The stability of matter: is really Maxwell wrong? (part 2).

    In a previous message I have tried to show that electrical systems exist which do not generate electromagnetic waves with appreciable energy even if such systems have parts in accelerated motion. Now I add a further example by which the meaning of what I tried to say becomes clearer. The problem...
  4. Thiwanka Jayasiri

    A Solving WIMP & Dark Matter Equation

    I'm trying to figure out how to arrive at the final expression, as given in the lecture notes. I tried to work this out by myself but getting different figure and units. I've considered the followings, normalize the equation from its values e.g. spins and x parameter, as g~100, x~10(m/t~10)...
  5. J

    I Alcubierre Metric: Explaining Dark Matter Halo Speed

    So I have a question regarding the Alcubierre metric and the phenomena of stars on outer edges of galaxies moving at higher velocities than their orbital calculations state they should. When taking the accelerating expansion of space into account due to dark energy, could a sub-luminal...
  6. Robin04

    I Is Dark Matter Really a Cold, Collisionless Fluid?

    How certain are scientists that the solution to the dark matter problem is a new, unknown particle (or more)? Theories that eliminate the need for new particle(s) and suggest modifications to the current understanding of gravity seem to get less attention. Why is that?
  7. Jaden159

    A Is energy contained in matter wave equals hv like EM waves?

    h is plank constant and v is frequency. I was using this to derive the TDSE. But I ran into problem because to substitute k^2 in E=h^2/8mpi^2 * k^2, I can use single derivative of psi squared or double derivative, both of which tend to give the correct answer. So, is my assumption of energy...
  8. phinds

    I Dark matter "halo" is a "flattened disk" ?

    I apologize for the fact that this information is 2nd hand but a very intelligent and reliable friend tells me that in “Dark Matter and the Dinosaurs” by Lisa Randall she hypothesizes a disk of dark matter, which she calls “Double-Disk Dark Matter (DDDM)” that is superimposed over the center of...
  9. B

    Do weight & strength matter in basketball?

    I am no basketball expert. I have never watched an entire basketball game in my life. However, several times in my life I have watched a few minutes of basketball games here and there enough so that I am familiar with the basics of the rules and objectives of each team in the sport of...
  10. L

    I Is Dark Matter Challenging Our Understanding of the Universe?

    I understand that the evidence for dark matter, although indirect, is quite strong. Yet there are a few things that puzzle me about the dark matter idea. If dark matter is the predominant form of matter in the universe, why does it have no effect on solar system dynamics? The solar system is...
  11. Mukund

    B Is There a Model That Includes Infinite Space and Finite Matter in Our Universe?

    We have a Universe that can be seen by Hubble maximum and we can imagine millions time more than that but if there is no boundary, there may be another millions of universe. Suppose we gather this all millions of universe and say this is a giant universe of universes and thus matter do not stop...
  12. N

    I Is Dark Matter Really Necessary in Our Understanding of the Universe?

    The bulge of the milky way is 40 parsecs in radius. There is 288.218 stars per cubic light-year in the milky way bulge. At the density, spacetime for the entire 40 parsec radius should be severely distorted. The total stellar mass of the bulge is about 25 billion Solar masses. The Milky Way has...
  13. Sandeep T S

    I Finding de Broglie's Original Paper on Matter Waves

    I was searching for d Broglie's original Papper of matter waves, I didn't get any thing on internet, please anyone help on this?
  14. A

    The stability of matter: is Maxwell really wrong?

    First of all: excuse me for my not good english written language. I come to the question with an example. Let us suppose two electrons are in space with initial velocity equal to zero. Given the Coulomb force such electrons will be submitted to an equal and opposite accelerations (for the action...
  15. W

    I Ratio of Normal to Dark Matter: Unchanged Since Beginning?

    Has the ratio of normal to dark matter remained the same since the beginning?
  16. BadgerBadger92

    B A quick theoretical question on dark matter

    This is a theoretical question that may not be rooted in reality. I hope this was the right section. Please clear up all misunderstandings. Since dark matter can’t emit light, could it be possible that dark matter is ionized matter? I always thought you needed electrons to emit light. Then that...
  17. J

    My E&M textbook claims that fields are a form of matter

    I'm studying out of Classical Electrodynamics by Ohanian and in chapter 2 (Electrostatics) he makes the following claim while discussing the electric field: I'm a little confused by this, and I can't seem to find any sources that share this view. I'm even more confused because in the...
  18. joelr

    B Dark Matter & Quantum Gravity: Is Unknown Property at Play?

    Regarding dark matter, is it possible that at the quantum level there is some unknown property to gravity that is making it appear that there is this dark matter attracting normal mass but it's actually just that on a galactic scale gravity acts different than GR predicts? Or is that completely...
  19. Ranku

    I False vacuum and matter density

    The false vacuum of the inflationary universe is described as a 'peculiar state of matter'. We know that matter density in the big bang universe dilutes as ρM ∝ a-3. Is it possible to assign a dilution rate to the 'peculiar state of matter' of the false vacuum as well?
  20. jim mcnamara

    I Is Quark Matter Truly Non-Strange?

    This paper: Bob Holdom, Jing Ren, and Chen Zhang. "Quark Matter May Not Be Strange." Physical Review Letters. DOI: 10.1103/PhysRevLett.120.222001 Proposes properties of elements further along the Periodic Table of elements - than the elements we have created so far. I cannot evaluate the...
  21. SlowThinker

    B Known properties and constraints of dark matter

    I'm wondering what properties of Dark Matter are known for certain. Such as: How much does it collide with itself, and with ordinary matter? What does ##\sigma/m\le 7cm^2/g## mean (and why is the estimate rising in more recent studies)? How does it compare with ordinary matter, e.g. liquid...
  22. Simon Peach

    B Discussing Sterile Neutrino Candidacy as Dark Matter

    I would like to hear what the opinions are. Could sterile neutrino's be dark matter? I'm sure this has been discussed if not here then somewhere.
  23. L

    I Are dark matter quarks displaced by visible matter?

    Are strongly interacting dark matter quarks displaced by visible matter? Chiral Gravitational Waves and Baryon Superfluid Dark Matter We develop a unified model of darkgenesis and baryogenesis involving strongly interacting dark quarks
  24. Sanborn Chase

    B What is the Speed of Light in Dark Matter?

    Does anyone know the speed of light in dark matter?
  25. L

    I Are displaced dark matter and curved spacetime same thing?

    If dark matter is a supersolid that fills 'empty' space and is displaced by visible matter, then is this the same notion as the spacetime fabric having mass and being curved by visible matter?
  26. I

    B Can Massless Particles Create Nanotubes That Capture Dark Matter?

    Can massless particles form some kind of nanotube that can trap other particles giving the nanotube mass? Is this dark matter?
  27. T

    B What, in essence, distinguishes light from matter?

    Before quantum mechanics, light was generally seen as a wave and matter as particles (biliards). From e.g. the discovery of the photoelectric effect, one saw that light can also be seen as a particle. From e.g. the double slit experiment, one makes the interpretation that matter can also be seen...
  28. B

    Gaussian Smoothing of the Matter Power Spectrum

    Homework Statement Consider the density perturbation smoothed with a Gaussian of scale ##\sigma##, ##\Delta_{\sigma}(\vec x') = \int d^3 \vec x \frac{e^{- \frac{(\vec x - \vec x')^2}{2 \sigma^2}}}{(2 \pi \sigma)^{3/2}} \Delta (\vec x)## Calculate the power spectrum ##P_{\Delta_{\sigma}}## of...
  29. Glurth

    I Transition from Normal Matter to Black Hole: Thought Experiment

    Thought experiment: single use of "magic" Setup: Let's assume we have a giant ball of water in space. Magic: Let's assume the water does not compress its center under its own gravity. (Constant density of 1 g/cm^3) Basic stuff: The mass of this ball of water, (since it does not compress)...
  30. M

    I "Centaurus A Contradicts Dark Matter Models"

    According to the article in Astronomy Magazine June 2018, the satellite galaxies of Centaurus A are rotating in the same direction in a relatively thin plane, vs randomly distributed if there is a dark matter halo/sphere surrounding large galaxies. Any thoughts on this new finding? I've only...
  31. T

    I Dark matter and old shell theorem

    From an outsiders view, it appears that the old shell theorem is relevant to the dark matter issue: If one views a spherical cluster of galaxies as an interconnected structure, gravity would increase linearly with distance from the center and be greatest at the edge of the cluster. For a spiral...
  32. R

    I Does dark matter contribute to my body mass?

    No I'm not a particularly big person with a weight issue. Somebody asked me this question and I don't know the answer, but somebody here will. OK, it's now accepted that dark matter is everywhere in the Universe, it tends to clump with regular matter because all matter is subject to gravity...
  33. Robin04

    I Transition between energy and mass

    How well is the transition between energy and mass understood? Energy can turn into matter and matter can turn into energy but what is actually happening between the two states? Imagining that matter just simply appears and disappears under an infinitesimal amount of time feels weird to me.
  34. A

    B Acceleration: Effects on Matter & Observers

    1) Is acceleration relative? 2) Can an observer in an accelerating body assume that he's at rest and everything else is accelerating except him and the object he's on? 3)Earth is accelerating and decelerating in its orbit around the sun all the time and yet we don't feel it, why? Is it only...
  35. T

    Exploring the Energy Transfer of Light and Heat in Matter

    I read that atoms transition from electronically excited to vibrationally excited. But how?
  36. F

    I Nature of matter: state question

    im curious as this question came up in a chemistry forum and it's more of a physics question I believe . State changes between elements of near similar number , what constitutes the extreme phase changes ? It was answered that there is no real answer for why the phase differences occurs at...
  37. K

    Thermodynamics equilibrium with respect to matter flow

    Homework Statement I don`t know if the image will show so I`m also adding a link to the image of the problem. This problem is a modification my professor made to the one in the link below(*), he changed the rigid diathermic partition into a movable partition. I`m supposed to find the...
  38. S

    I Charged Particles Radiating in "Free Fall" into Black Holes

    Hello everyone, "Does a charged particle radiate in free-fall?". I read many threads on this subject and I was surprised to find out that there is no unanimous "Yes or No" answer to this question. Here is an interesting answer from researchgate.net: The question is widely discussed in the...
  39. mjda

    I How to describe the Sun's interior?

    My question to you is this... Can the interior of the Sun be described as an ideal gas? From my knowledge, to describe a body of gas as an ideal gas, the separation between the particles must be much greater than the size of the actual particles. How could one justify whether the Sun fits this?
  40. Ranku

    B Density of matter at a galactic center

    Why is the density of matter greater near the galactic center?
  41. M

    MHB Bridge Game: Does Luck Matter?

    4 people are playing the Bridge Game, out of 4 players 1 player hasn't received a single Ace after third turn, does he have the right to complain that he doesn't have luck? To clarify some things - There are 32 cards (4 types), each of the four players get 8 cards for each turn. The problem is...
  42. AD MCFC

    A The Future of "Soft Matter Physics"

    Hi all, I am trying to learn more about this field. Whether you work or have worked in this area or not, I would like to know where Soft Matter is going in terms of theory and applications. Thanks, A.D. *I apologize in advance if there are already many threads specifically addressing this...
  43. ohwilleke

    B What fraction of the matter in the universe is in black holes?

    Conceptually, at least, this is a simple question, although I recognize that it might be hard to calculate in practice from available data. The matter-energy budget of the universe is measured (in a model dependent way) to consist of a certain percentage of dark energy, a certain percentage of...
  44. Peter Morgan

    A Generalized free fields as dark matter?

    @vanhees71 reminds us that which suggests something I've wondered about for a while, whether dark matter might be adequately modeled by generalized free fields, which do not have asymptotic free states. Ray Streater, in Rep. Prog. Phys. 1975 38 771-846, "Outline of axiomatic relativistic...
  45. A

    B Mass-Energy Equivalence: Matter as Potential Energy?

    I think mass as a form of potential energy and am always told that this is wrong. According to wiki: "In physics, potential energy is the energy possessed by an object because of its position relative to other objects, stresses within itself, its electric charge, or other factors." Why do this...
  46. M

    I Is a galaxy's halo displaced dark matter?

    Scientists Thought All Galaxies Had Dark Matter, but They Just Found One Without It Could dark matter fill 'empty' space, strongly interact with visible matter and be displaced by visible matter? Could the reason for the mistaken notion the galaxy is missing dark matter is that the galaxy is...
  47. N

    I Can matter come into existence in empty space?

    A question arose over a simplification I wrote on another subject. My i information say's that matters antimatter pairs are generated in what is known to be very empty space such as the voids within the cosmic web. When I read about this it was considered anomalous but definitely verified. Now...
  48. EnigmaticField

    Programs Apply for a PhD in theoretical condensed matter physics?

    I did research on theoretical formulations in general relativity during my MSc studies. I look forward to pursuing PhD and have searched many universities and some research institutes for suitable research themes, but haven't found many research groups undertaking research consistent with my...
  49. phinds

    I Galaxy with no dark matter? (NGC1052-DF2)

    Just noticed this article. Wonder if anyone here has further info. Sounds very interesting. http://www.bbc.com/news/science-environment-43543195
  50. Q

    I Can dark matter explain dark energy?

    Why do we need the theory of dark energy? I know the it is claimed that dark-matter has no affect on the electromagnetic spectrum. How do we know the affects attributed to dark-energy aren't affects caused by dark-matter? Dark-energy is claimed to be causing the universe to expand at an...
Back
Top