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Define Mass

  1. Mar 30, 2005 #1
    Upon my recent studies i have discovered various methods of defining mass in various situations. It has come to my attention that mass is somewhat undefined without the use of interacting parameters.

    Your thoughts?
  2. jcsd
  3. Mar 30, 2005 #2


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    Yes,in Newton's formulation of classical mechanics it's defined as the proportionality constant between the body's acceleration and the resultant of the imprimed forces...

    There's nothing more to it.

    In other formulations of classical mechanics (Hamilton,Lagrange & H-J),it's undefined.

  4. Apr 13, 2005 #3
    Hey, take it easy when you are talking to me, mang.
  5. Apr 14, 2005 #4
    Well, I think everybody agrees that mass is a property of matter.

    Supposedly, in the standard model of particle physics, the mass of all particles in the universe is obtained by a kind of partcles not-yet-discovered called higgs which cause antigravity and the field that gives mass.
  6. Apr 14, 2005 #5


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    In the Standard Model, most of the baryonic mass, which is what we usually call mass, is due to the binding energy of the gluons holding the quarks inside the baryons, notably the proton and neutron. The mass of the long-lived quarks, the u, d, and s quarks, plus the electron mass, all together are trivial in comparison with the binding energy.
  7. Apr 15, 2005 #6
    say basically in the standard model glouns make up the basic unit of all mass meaning nothing comprises glouns.?
  8. Apr 15, 2005 #7
    Wouldn't it be better to say that mass is a property of energy and matter a product of mass? This doesn't really help as energy is also undefined as is mass.
  9. Apr 15, 2005 #8
    In the standard model there are 3 gauge groups of fermions but we have yet to determine why that is so. I believe there is something which governs the generations.
  10. Apr 15, 2005 #9

    True. None of the three (matter, mass and energy) are fundamental.


    Energy is the ability of matter to do work: apply a force during a distance.

    Matter is something that ocupies space and has mass.

    Mass is the amount of matter that a body has.

    When matter has more mass it has more energy.

    When matter has more energy it has more mass.

    When mass is compresed energy is compresed.


    I could carry on for ever.
  11. Apr 15, 2005 #10


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    The gluons themselves are massless. But the force of their attraction, to quarks and to each other, entails energy, and this energy appears as the greater part of the mass of the baryon.
  12. Apr 15, 2005 #11
    Do you think light could be the mediator of gravity?

    Basically energy = power x time which i believe is a non-sequitur because according to general relativity time equals energy, length and mass.
    Last edited: Apr 15, 2005
  13. Apr 15, 2005 #12


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    Say what? Where in general relativity do you get time equals energy, length, and mass? And if you accept general relativity why would you need light to mediate gravity?
  14. Apr 16, 2005 #13
    There is no correct definition of energy and work. Though i believe time also to be energy because every second equals to 9,192,631,770 complete oscillations of the cesium-133 atom.
  15. Apr 16, 2005 #14


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    According to whose definition of "correct"?

    Oh, geez! Because we measure time with a clock, therefore time is a mechanism? If we use a pendulum does time swing back and forth?
  16. Apr 17, 2005 #15
    There is no correct definition of Energy because there is no correct definition of correct.
  17. Apr 17, 2005 #16
    As Einstein said, gravity curves 4-dimensional space-time but space-time is not real. It's abstract. I believe that a "force" which curves our vacuum cannot be weak.

    The gravitational phenomena can be explained by the earth's core, a quantum-dynamical effect. In fact stars have a size limit, which i think is consistent with this. Inside the core of stars, the pressure is very high and mass is consistently converted into energy. As the electron surrounds about the proton, so does the moon surround about the earth.
    Last edited: Apr 17, 2005
  18. Apr 17, 2005 #17


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    You can believe what you like, but Einstein's GR has an enormous amount of observational and predictive evidence to its credit, and your opinion has none.
  19. Apr 17, 2005 #18
    Your theory breaks down and for good. Why does it break down? Because space and time are not more important than energy and work. Gravitation is a quantum-dynamical effect, not some warping of space-time which doesn't even exist. :biggrin:

    The main problems with GR are:

    1) Gravitational singularity
    2) Expansion of space (from a singularity) FTL.

    PS: Don't get me wrong. I think GR is a great work of art. I just can't see it as a physical reality. There is some "engine" in nature but we have to figure out what that is.
    Last edited: Apr 17, 2005
  20. Apr 27, 2005 #19
    define mass-- mass is a quantity possessing units related to a generally accecpted standard that responds to cause and effect....fap

    If iI were at some place in some other reality other than this one, however ,everything else being the same........ the idea of mass wether called that or not would be something that is relational and therefore something that could be quantified with absolutes and responsive to cause and effects/affects so mass would be a measure of something compared to a tangible absolute like maybe water.

    the current hoax created by Newton using the word gravity some unknown alluded to but not identifiable force is useless for anybody that actually has to go out and make a living, a cause and affect reality, so naturally when a definition depends upon an unmeasurable ubiquitous variable that could easily be described by simpler provable means then we're going to end up with incomplete definitions like E=mc^2 unprovable..............just an observation
  21. Apr 28, 2005 #20


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    You are the only person I ever heard of who had a practical problem with Newtonian dynamics. Civil engineers seem to work with it OK.
  22. Apr 28, 2005 #21
    Mass is an active area of research. I think it has something to do with color superconductivity.

    Strange that 2300 yrs after aristotle, we still havn't figured out what mass is.
  23. May 2, 2005 #22
    What's wrong with this? Mass is concentrated energy. You can convert mass to energy. But the BB created mass from energy. String (M) theory, which is an intangible mathematical construct, does not deal with mass at all.(?) Higgs particles, which have recently been found (for real), may have no mass or charge. So what are they? Where does that leave any definition of mass? Linda
  24. May 3, 2005 #23

    do you have a link of somewhere in the internet where this "higgs have been found" announcement is stated and explained/detailed?? This could change many things, and make you more reliable.
  25. May 28, 2005 #24


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    The Higgs Boson has not been found. I don't know where she got that idea from.
  26. May 30, 2005 #25
    Mass could be termed the product of self interaction. Your ability to move matter is related to the self interaction of it.
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