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A string of honest questions

  1. Feb 6, 2006 #1
    Is it true that mass and energy are interchangable? If mass were to be defined as "the force of matter", is it then true that matter and energy are two states of the same thing? Is matter condensed or frozen energy? Could radioactive decay be defined as the sublimation of matter into energy? Is it fair to conclude that no two discernable entities of matter could ever possibly come into direct contact with each other, but instead can only forever appraoch each other?

    If I place two glass marbles up against each other and examine the point of apparant contact very closely what exactly could I expect to discover? As I magnify this point more and more will I not find that the surface of the glass marbles is far from even and smooth? Will I not also initially see that there are probably several dozens and perhaps thousands of points that appear to be touching on the two surfaces that are now irregular and rough shod? Able to choose only one point to zoom in on at a time will I not eventually discover that each point of apparant contact reacts the same to my inspection, in that it proliferates into many more points the more I magnify it? Eventually when I zoom in to the "molecular" level doesnt my question change from that of one inquiring if two marbles can touch to one asking if two molecules can touch? As I zoom in even more, thus altering my perspective yet again, doesnt my question also change? Soon I am now observing the weak and strong nuclear forces, am I not? I press the two marbles together as hard as I can, but as I continue to zoom in it appears that the marbles (which by now appear to be two dense galaxies of particulate debris organized by so many forces I dont understand) are pushing against each other before they touch--is this true, or even fair to say?

    I apologize for the breathlessly long inquiry. I have a high schoolers grasp of physics, perhaps even less, and I'd definately appreciate any response offered to the above.
  2. jcsd
  3. Feb 6, 2006 #2


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    Yes to all those. But its not the "force of matter" as you say.

    No, well sometimes, in nuclear decay there are three particles: alpha, beta, and gamma. Alpha particles are the same as negatively charged heliums, beta particles are electrons, and gamma particles are photons. Way down at the quantum level, everything is just energy and waves, photons can be considered just energy (then again, everything is), and electrons are the next step up into being "matter," then helium, is matter.

    Yes, in fact if you blew up a billiards ball up to the size of the Earth, the billiards ball would be much rougher.

    Yes, yes, yes...

    Ha! You got one wrong! The nuclear forces are inside the nucleus, and are rather nuclear. You would not observe these at this level, and if you were looking between the marbles. You would observe the electromagnetic force, bonding molecules and atoms together. Galaxies, would be too small, to compare it to.

    No way man, you're smart, keep going, visit often. Also, I like to hang now in General Discussion https://www.physicsforums.com/forumdisplay.php?s=&daysprune=30&f=14 Which is good if you feel like you don't know or can't talk to any smart people.
  4. Feb 9, 2006 #3
    It would be better to say there are 3 types of decay, not particles.

    Alpha decay spits a helium nucleus (which is positively charged) out of the nucleus.

    Beta decay can come in two different types. Beta decay turns a neutron into a proton via quark change, and emits an electron and an anti-electron neutrino. Inverse beta decay emits a positron and an electron neutrino (ie does the reverse of normal decay).

    And then there's the standard gamma decay emitting a photon.
  5. Feb 9, 2006 #4


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    :redface: Thanks for clarifying and correcting me.

    AlphaNumeric, I believe has posted definitions of what is happening in nuclear decays in the quantum mechanical sense.

    In chemistry though, and simpler physics, as opposed to quantum mechanics, you would say alpha particle, beta particle, gamma particle, He2+, e-/e+, gamma.
    Last edited: Feb 9, 2006
  6. Feb 10, 2006 #5


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    Pretty much so. If you have an isolated system, that system has a mass, and if you add energy to the system, the mass increases. If you subtract energy from the system, its mass decreases.

    Huh? That phrase doesn't have any readily apparent meaning

    I think you are "leaping ahead" too much of the evidence, bounding on the verge of not asking questions but making speculative statements.

    Stick with what we know. We know that particles and anti-particles can mutually annhilate. We also know that this proces as a whole conserves energy.
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