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Rest mass of Hydrogen

  1. Feb 4, 2013 #1
    Hello all .
    Rest mass of Hydrogen is more than rest mass of one proton and one electron ?
    I mean virtual photon between electron and proton give extra mass to Hydrogen ?
    Like gluon between quarks ?

    and another example : mass of solar system is more than mass of One to One planets and sun ?
    I mean gravity between them give extra mass to solar system for an outside observer ?
  2. jcsd
  3. Feb 4, 2013 #2
    The rest mass of hydrogen is less than the mass of one proton and one electron: 13.6 eV less, which is the binding energy of the atom.

    Similarly for the solar system: the mass of the solar system is less than the sum of the masses of the Sun and the planets, because of the negative gravitational binding energy of the solar system.
  4. Feb 5, 2013 #3

    This binding energy are virtual photons ?
  5. Feb 5, 2013 #4


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    No, energy is not made of photons. Energy simply has mass, and if you look at an electron and a proton before they bind together they have more energy than they do after they bind together. The energy is lost as EM radiation when they two bind.
  6. Feb 5, 2013 #5
    I really don't understand good .
    The EM radiation interact between electron and proton in atom called virtual photons .
    Binding energy between quarks that called gluons and make 95 percent mass of proton .
    So what's the name of binding energy that give extra mass to hydrogen ? EM radition ? or virtual photon ?
    This binding energy travel at c ?

    what's the name binding energy between protons and nortons ? that name is boson W and Z ?

    What's name binding energy between earth and moon ? it's gravity ?
  7. Feb 5, 2013 #6
    Actually, vacuum is filled with virtual particles even when there are no protons or electrons. In the presence of charged particles configuration of the e/m field changes, so you shouldn't be surprised that energy may actually decrease.
  8. Feb 5, 2013 #7


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    Virtual photons mediate the EM force. They are NOT EM radiation. These photons do NOT radiation outwards from a source or obey standard rules for EM Waves.

    This is incorrect. The virtual gluons mediate the color force between quarks, but they do NOT compose energy. Energy is not a "thing" like this.

    It is quite simply, energy. And as has been stated before, hydrogen has LESS mass than a proton and an electron. You seem to think that binding energy results in MORE mass for the bound objects. This is not true. 99% of the mass of a proton comes from the kinetic energy of the quarks and from the energy of the field, but this is not "binding energy".

    No, you are naming particles. Energy is not made up of particles, it is simply energy.

    I think you should read what energy is. Try here: http://en.wikipedia.org/wiki/Energy
    I like the quote from Richard Feynman they have here:

    The question "what is energy?" is difficult to answer in a simple, intuitive way, although energy can be rigorously defined in theoretical physics. In the words of Richard Feynman, "It is important to realize that in physics today, we have no knowledge what energy is. We do not have a picture that energy comes in little blobs of a definite amount.".[1]
  9. Feb 8, 2013 #8
    I know virtual photons are difference but i say virtual photons are equivalent energy and they are between electron and proton so measured as mass .

    What's compose energy ? is there any define in physic for compose energy ?

    Hydrogen has LESS mass Or MORE mass than a proton and an electron ? i think you were writing wrong .

    Can you give me a reference or link for this ?
    Thanks for you answering .
  10. Feb 8, 2013 #9


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    I disagree on the basis that I've never ever heard of this before and it doesn't make any sense to me to say that virtual photons are "equivalent energy".

    Energy is not a thing. It is a measure of the ability for one system to perform work on another system. It is difficult to understand, but energy is not a particle. It is not a physical object. Think of what Work is. Work, as a basic definition, is when a force causes displacement of a body. That's it. If energy is made up of something, then Work would have to be made up of something also. Given that definition of work, does that seem reasonable?

    I am not. A Hydrogen atom has LESS mass than an unbound proton and electron.
    The explanation is that the electron and proton bind together and RELEASE energy, which causes the atom to have LESS mass than the particles before they bound together.

    In the opening paragraph of the article linked below:

    In the modern Standard Model of particle physics, the proton is a hadron, composed of quarks. Prior to that model becoming a consensus in the physics community, the proton was considered a fundamental particle. In the modern view, a proton is composed of three valence quarks: two up quarks and one down quark. The rest masses of the quarks are thought to contribute only about 1% of the proton's mass. The remainder of the proton mass is due to the kinetic energy of the quarks and to the energy of the gluon fields that bind the quarks together.

    And a more in depth explanation further down:

    In quantum chromodynamics, the modern theory of the nuclear force, most of the mass of the proton and the neutron is explained by special relativity. The mass of the proton is about 80-100 times greater than the sum of the rest masses of the quarks that make it up, while the gluons have zero rest mass. The extra energy of the quarks and gluons in a region within a proton, as compared to the rest energy of the quarks alone in the QCD vacuum, accounts for almost 99% of the mass. The rest mass of the proton is, thus, the invariant mass of the system of moving quarks and gluons that make up the particle, and, in such systems, even the energy of massless particles is still measured as part of the rest mass of the system.

  11. Feb 8, 2013 #10
    All particles are made of energy and virtual photons too .
    And they bind the electron and proton together in hydrogen atom .
    So virtual photons are measured as part of the rest mass of the hydrogen .
    Is not true ?

    Thanks for other answering i got it .
  12. Feb 8, 2013 #11


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    No I don't believe this is true. Fundamental particles have a variety of intrinsic properties, one of which is invariant mass. This mass can be equated into a certain amount of energy for certain purposes but I don't think you can say that particles are *made of energy*.

    I really don't want to try to answer this, as the subject of virtual particles is an extremely complicated one and is better off posed as a separate question in the Quantum Physics forum.
  13. Feb 9, 2013 #12
    Energy has different forms and all particles are also a form of energy .
    Mass and energy are the same thing Einstein did demonstrate .
  14. Feb 9, 2013 #13
    no, you are wrong. both of the systems you described have lower mass-energy than the summation of the particles would imply.
  15. Feb 9, 2013 #14

    Vanadium 50

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    Big Bounce, we really discourage learning by the technique of posting a parade of incorrect statements, hoping they will be corrected by others. It's inefficient, and it tends to make other people cross.
  16. Feb 9, 2013 #15
    Does the rest mass of both situation related to Higgs mechanism? I have least knowledge regarding this, I am just curious whether these situation related to the Higgs or not..
  17. Feb 9, 2013 #16


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    No, this is incorrect as well. Energy and mass are not the same thing. You can easily see this by looking at the definitions of mass and energy. They are related however. But so what? Many things in science are related.


    That's better off being brought up in it's own thread. Actually, if you use the search function on the bar at the top of the page I bet you could find plenty of threads on the Higgs mechanism.
  18. Feb 9, 2013 #17
    No i think you are wrong .

    when two quantities are related only by a constant multiple we say they are different ways of looking at the same thing.
    Kilograms and pounds are different ways to look at mass , you can tell because they are related by a constant multiple (1kg=2.20462lbs)
    Energy and frequency of a photon are the same thing (related by plank's constant)
    Mass and energy are the same thing too, for the same reason (related by the invariant speed of light).

    Related by a constant ? like what ?
  19. Feb 9, 2013 #18


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    Then please provide some reference stating that energy and mass are the same thing. And not only that, but justifies it too.

    The mass-energy equivalence equation is NOT a definition of either mass or energy. It is a mathematical way of relating the amount of mass associated with an amount of energy, and the amount of energy associated with an amount of mass. The topic is far more complicated than one equation.
    Also, the equation is missing the rest of it anyways. The full version includes momentum as well. It is E2 = m2c4+p2c2.
    What does this about momentum now? Is it too also energy? No. It is not.
    Kilograms and pounds are units of measurements. They are not anything in and of themselves. For example, the Joule is the unit of measurement for energy and work. Without any concept of energy or work a Joule would be meaningless. It means nothing by itself.

    You are correct in that knowing either the frequency of the EM wave or the energy of the photon you can find the other, but this in no way means energy and frequency are the same things. They are two different concepts that mean two different things. You seem to think that just because you can figure out one thing using another that makes them the same. It does not. It is important to understand that, by itself, a mathematical equation tells us nothing about what something is. It only allows us to do calculations and may help us understand something when we look deeper into it.

    Here's a list of constants. You will find that most, if not all of them have a mathematical equation relating them to other things like E=mc2 does.

  20. Feb 9, 2013 #19

    Vanadium 50

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    That's simply not correct. If I have a 100Ω resistor, and measure its current and the volatge across it, they are related by a constant, but current and voltage are not the same thing.

    Let me repeat:

  21. Feb 10, 2013 #20
    The equation e=mc^2 justifies it .
    Einstein's most famous equation is E=mc^2. It means that energy and mass are different forms of the same thing.


    Another reason :

    Matter and Antimatter annihilation is an example of converting energy in one form (electrons and positrons) into another (high-energy photons) .
    Or A photon it's a packet of energy can pair-produce to make an electron and a positron too .

    No we can say it's a definition
    The language of physics is mathematics Think of what Work is . Work is when a force causes displacement of a body . we can translate this definition to mathematics with the equation w=fd

    No we can say momentum and energy are same thing too , think about photons
    Photons are packets of energy

    Your equation is
    E2 = m2c4+p2c2.

    For a photon the rest mass term vanishes, and you get E=pc.
    So energy and Momentum are related by a constant ( related by the invariant speed of light).

    See the Pythagorean relationship between Energy (E), Mass (m) and Momentum (p) .

    No they are same thing because frequency of photon can do work . if frequency be higher photon can do work more .

    No that's not true . in equation RI=V resistor is not a constant voltage and current can be a constant too ,
    for example : I have a 100 amperes , and measure its resistor and the voltage across it
    Is that mean R and V are same thing ? no .
    But in equation e=mc^2 we just have a constant and it's speed of light .
    Hope you understand .
    Last edited: Feb 10, 2013
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