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Crazy idea about atomic structure

  1. Feb 7, 2009 #1
    Is it generally assumed that there is a smallest building block of matter? Or is it assumed that there is always a smaller particle within any particle? because i was thinking in my calc 2 class the other day...

    If you have, say, a water bottle on a table, and you assume that there is always a smaller building block of matter, there are an infinite number of places that the waterbottle can be. So the chances of the water bottle being in any one place is equal to 1/x, where x is the number of possibilites... therefore if there ARE an infinite number of smaller particles matter has a 0% chance of existing in any location.


    lim(1/x)
    x[tex]\rightarrow[/tex]inf

    (not very good with the whole symbols gig)

    not a 0.0000000001% or something like that, a 0%. so can matter then not exist unless there is a definite smallest building block? if there is, the chances are just one over some very, very, very large number but still exist.
    Does this say that, unless there is a smallest possible "building block" of matter, matter cannot exist and so everything is in our heads? lol.


    I dont have any physics backgrounds whatsoever, just thought id get this out there.
     
  2. jcsd
  3. Feb 7, 2009 #2

    Nabeshin

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    According to the standard model, the fundamental particles of the universe are considered to be fundamental (i.e the most basic components). Due to the heisenberg uncertainty principle, however, one can never know the location and velocity of a particle at the same time. This introduces an uncertainty into the position of objects, and the best we can really say is the probability that they are at (x,y,z).

    I'm not sure how you jumped from assuming smaller building blocks of matter to an infinite number of places the water bottle can be...
     
  4. Feb 7, 2009 #3
    You are hung up on the concept of a continuous probability distribution. Electrons have no measureable size, but we can still calculate the charge density of an atomic orbital using a continuous wavefunction, which is essentially a probability distribution. The probability of an electron occupying a specific point in an atom is vanishingly small, but there is a non-zero probability of the electron occupying a finite volume.
     
  5. Feb 7, 2009 #4
    Apparently i need to clarify. A good way to explain what i am saying is the cliche paradox of crossing a room. You have to get to the half-way point, as well as the midpoint between the halfway point and the start, etc. The idea is that there are then an infinite number of locations you must reach so you can't cross the room. This one is obviously disproved by the fact that, although there are an infinite number of places you have to get to, they are infinitely small as well. Like a convergent rather than divergent graph. But if you ask the number of places you can be on that infinite number of infinitely small spaces, then the chances are theoretically 1/infinity, AKA impossible, unless the spaces are just incalculatably miniscule, which discounts the entire paradox from the start because there really aren't an infinite number of places to get to. Right?
    Back to the electron thing mentioned by someone above, how can there be a nonzero chance of the electron being somewhere in the atom? Besides the fact that it is there. How are there not an infinite amount of infinitely small spaces within the atom at which the electron could be?
     
  6. Feb 7, 2009 #5
    Basically you are saying that if you are going to throw a dart at a a dart board, the probability that it lands at some exactly specified location is zero. You need to specify a finite size area, however small, and ask the probability of the dart striking this area in order to obtain a non-zero result.
     
  7. Feb 7, 2009 #6
    Your then saying that there is no definite smallest "building block" of matter. If there were one, then the chance that the dart will be in any exact location is not 0%, as you stated, but some VERY SMALL yet still non-zero number, determined by how small the smallest building block is, the size of the point of the dart, the size of the dartboard, etc.

    if there is no definite smallest particle and the chance of the dart being in any exact location is 1/infinity = 0%, it essentially is saying, to me, that matter cannot exist because there is a 0% chance that any matter will be anywhere within a realm of infinite possiblities. Yet the dart is still in what appears to be a definite location on the board. and many people would argue that matter most definitely exists.

    I'm beginning to realize how pointless this whole thread has been. The answer seems clearly to be that there is a definite smallest particle of matter and thus always a non-zero, however small, possibility of it existing in any exact location. or its all in our minds, but I think the first idea is most plausible.

    The real point of this thread was for people to come up with or cite other theories as to why the dart IS in a definite place on the board, etc. other than the two above. Its just for fun really, to get really weird ideas out there to look at. Cause u never know lol. i think it's only fair to assume that there is a smallest particle of matter if no other ideas as to why this is true exist.


    This is probably one of the most pointless threads in the history of the internet. lol
     
  8. Feb 7, 2009 #7
    I would really like someone to answer this
     
  9. Feb 9, 2009 #8
    I'm no physicist, or anything close, but reverse-engineering the question might be a better way to go. Like, we know there is such a thing as matter, so what does that say about weather there is a truly fundamental particle? And if particles are in actuality just waves anyway (like strings, etc), then it doesn't really matter. The "waves" can masquerade as any particle they like. Perhaps there really aren't any particles at all.
     
  10. Feb 9, 2009 #9
    THANK YOU for being almost the only one here who knows what i was trying to say. lol

    I was trying to get ppl to list other ideas as to how matter can exist the way that it does other than the obvious idea of a definite smallest particle.
     
  11. Feb 9, 2009 #10
    I don't know if I understand your question correctly, but you seem to be under the impression that if there would not be a smallest particle (there would always be a smaller particle possible) this would automatically imply that an object cannot have a definite position.

    If the particles you speak of behave classicaly (they have exactly defined position) then I don't see how one follows from the other.

    Surely, the first statement implies that particles will eventually become infinitely small, but that doesn't mean that they cannot still have a definitive position? Not everything is build up out of particles! In fact, the majority of "everything" is just empty space between particles. Between two atoms, or even within the atom, most of it is just empty space. So I don't see why an infinitely small particle cannot exist in empty space (ofcourse, it wouldn't be empty anymore then).

    In other words, you are thinking that space is quantisized (sp?), so that objects (particles) can only exist on certain "points on a grid", and if you would move a particle it would jump from one point on the grid to the next, instead of continuously moving between two 'points'?
     
  12. Feb 10, 2009 #11
    Yet another way to explain it: you have a particle in empty space. Forget about the whole size thing. in empty space there are no constraints on where the particle can be, correct? no "points on the grid," as you put it, for it to "jump" to. so the number of places it can be within that empty space are infinite. There is always another measurement that is smaller, to an infinite extent, at which the particle can be. So the chances of the particle being in any one place are one over an infinite number of possibilties= 0% chance. So how does matter exist?

    If there were another form of DEFINITELY small matter, or definitley small dark matter, or something completely different but with the same idea, in what was referred to as "empty space" above, then you suddenly have only a limited number of places that the particle can be, and thus a non-zero chance that it exists in any location.

    Unless the idea that particles are actually waves and thus non existent (mentioned by Asensory) is true, how can matter exist unless it IS quantisized (sp? for me too)? if it is not then the chances of a particle existing in any location are 0%, rather than some insanely small yet non-zero chance. Correct?
     
  13. Feb 10, 2009 #12
    I think that yes, point particles have a 0% chance to be in an exactly defined location. If you ask: "what is the chance of finding a particle at position x" the chance is zero.
    What you have to do is specify a range of positions in which the particle can be. The chance of a particle being in the range x to x + dx (where dx can be infinitely small) is not (always) zero.
    This has nothing to do with the question 'does matter exist'.

    It is the same with much more trivial examples, like the age of a random person.
    If you walk up to a random person on the street and ask him his age, the chance that his age is exactly 31 years, 4 months, 8 days, 9 hours, 12 minutes and 44 seconds is zero.
    The chance that his age is between the above and 31y, 4m, 8d, 9h, 12m and 45 seconds is NOT zero (although probably very small).
    Does this mean to you that age doesn't exist?
     
  14. Feb 10, 2009 #13
    I think, then, that yes, time cannot exist unless there is something quantifying it in the same way. Any reason why time cannot be the same way? Perhaps time runs at a certain frequency. Then there is a non-zero chance that he was born at that exact point in time. But with the way that our brains work, we interperet it as a continuous stream. Maybe we can't interperet it fast enough to see each tiny moment separately.
     
  15. Feb 10, 2009 #14
    You're interpreting what I said in the wrong way.

    Zero probability does NOT mean that it will never happen.


    Read this:
    http://en.wikipedia.org/wiki/Almost_surely

    Think of a dartboard where you throw a dart arrow at. The chance that it hits a certain exact point P on the board is zero. But surely, the dart must hit SOMEWHERE on the board, so you are certain that such a point P is going to be hit, but the probability was zero!

    The probability of something is usually the integral over a short range from a to b of a probability density [tex]\rho(x)[/tex]:
    [tex]P = \int_a^b \rho(x) \, dx[/tex]

    If a = b (which is the case if you do not specify a range but an exact POINT) then you are integrating over nothing at all and P = 0.
     
  16. Feb 10, 2009 #15
    I understand what you are saying completely; however, i was thinking that if we say that there is a smallest particle or that something like dark matter defines the number of places in which it can be, the chance is not zero but some small non-zero number. But apparently the idea is somehow flawed.

    So assuming that you are right as the wikipedia page says you are, my question is this: can you prove it? Can you somehow show me that the idea of "almost sure" is the reason why this happens, rather than a definite smallest particle creating a non-zero chance in the dartboard, time not happening as a constant stream but many short intervals creating a non-zero chance in the age of a person, or in the example mentioned on wikipedia, the diagonal of a square, the points on the diagonal DO exist as a non-zero chance because there is a certain smallest measurement at which the dart can hit because of dark matter or a smallest particle or something of the sort?
     
  17. Sep 10, 2010 #16

    taylaron

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    Salter, you're having a similar thought that i'm having. Although, I am under the suspicion that there is no such thing as a smallest particle.

    Regarding your probability conundrum: it seems the probability of an entity existing in a defined point in space completely breaks down under the assumption that there is a smallest possible distance (like the grid mentioned earlier). When this was being discussed, the first thing that came to my mind was the well understood fact that there are an infinite number of numbers. to elaborate the obvious: If you take a number line, there are an infinite number of locations between say 0 and 1. Its all an issue of accuracy. It seems obvious that when someone describes an entity as existing at say (x,y,z) they're abandoning the concept of absolute distance. It all comes down to an issue of accuracy.

    The statement saying that just because something has a 0% probability of happening does NOT mean it will not happen contradicts the definition of probability. Regardless of what all the big-wigs mathematicians say. 100% probability means it WILL happen and 0% probability mean that it will NOT happen. If mathematicians claim 0% probability doesn't mean it wont happen, they need to coin a new term that doesn't contradict the definition of probability.

    Also, in my mind (hah, which means nothing...) Just because an entity (however large) has an infinite number of places it can be in a defined region (haha, despite the limited accuracy in describing the region's bounds) does not dictate that there must be an infinitely small particle to correspond with the increasing accuracy of its position in space. (I am not suggesting there is or isn't a smallest possible particle)

    The battle of finding the smallest particle seems pointless in my eyes IF: when scientists increase and increase the quantity of energy used in particle accelerators, yet continue to find smaller and smaller particles. Pretty soon (at this rate) we're going to need a particle accelerator the size of our solar system to figure out if the smallest particle identified can be split further.
    Furthermore, the ability to detect more and more minute amounts of energy in the ever so small particles will become an issue. Background noise (regardless of shielding and since 100% purity is impossible) will prevent experiments from being able to detect the inconceivably small fluctuations in matter's properties that would need to be measured.

    If there is indeed no such thing as a smallest particle, what scientists have done is figured out a lot of different possible pieces an atom can be split into. Just because one identifies a smaller piece in an atom, does not mean it has to be made of them... Think about that one.
    I expect to hear lots of gnashing of teeth over that statement...
    Also, (If i understood correctly) i'm pretty sure dark matter has no influence over the ability to affect the accuracy of describing a position in space.

    I'm very confident when I say there is no limit to the accuracy of distance. Think of the number line!

    It seems the argument over the the 'most fundamental' particle is flawed by our limitation of practical experiments (*ahem- the solar system sized particle accelerator)
     
  18. Sep 10, 2010 #17

    ZapperZ

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    I agree with the statement that this could be one of the most pointless thread on the internet.

    Many of the arguments put forward isn't based on physics, but rather, based on a matter of TASTES. Look closely, especially the last post.

    I'm the LAST person who will want to defend such reductionism in elementary particle physics (one can already see my stand on this based on all the argument I've posted on emergent phenomena). However, there is a huge amount of knowledge that has been gained from the understanding of fundamental particles that has transcends beyond just particle physics. The synergy between the various theories of condensed matter physics and elementary particle physics is one clear example. And the excitement being given to the newly discovered topological insulator, from BOTH camps, is no coincidence. And these are stated NOT based on my personal tastes either.

    I have no idea why this thread, from Feb. of last year, is being dug up. The OP has several SEVERE misunderstanding about the "atom" and basic QM. Rather than correcting that, it seems that it is OK to extrapolate faulty knowledge into something "new".

    Zz.
     
  19. Sep 11, 2010 #18
    A topological insulator is a material that behaves as an insulator in its interior while permitting the movement of charges on its boundary. ..
    This is trillions of various particles salter is dealing with a single particle.

    condensed matter physics is based on wavelength measurement, but SALTER asks about mass.

    But what is mass, if we define it as ‘matter’ or ‘energy’ (i.e. ‘something’) then clearly there is a limit to compression, hence the incompressible fractions of condensed matter physics. However if ‘force’ is included such as the gravitational force of gravitons then the limit of compression is a dimensionless zero point. Quantum physics uses the term point-like particle but fails to define the term.

    The confusion arises from the use of different terms in non-causal theories with each group of researchers using the terms best fitted to their concept often without precise definition of the term and always with no explanation of fundamental cause.
     
    Last edited: Sep 11, 2010
  20. Sep 11, 2010 #19

    ZapperZ

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    I'm not sure what the point is here. I was replying to taylaron's post. You also have made a severe misrepresentation of the relevance of not only condensed matter physics (based on a wavelength measurement??) and why topological insulator is important even fundamentally as far as elementary particles is concerned. Read, for example, why it has been called the "Star Material" in a Nature article (Nature v.466, p.310 (2010)).

    This clearly debunks taylaron's argument that "...The battle of finding the smallest particle seems pointless in my eyes IF: when scientists increase and increase the quantity of energy used in particle accelerators, yet continue to find smaller and smaller particles. The fact that these two separate fields (condensed matter physics and elementary particle physics) can, in fact, feed on each other's advances, is one clear proof that debunks such sentiment. And no one in their right mind would argue that condensed matter physics is useless, unless one is willing to chuck away all the modern electronics.

    So I think you missed the point of my post.

    Zz.
     
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