Pages:
1
2 |
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
I don't think your question was impertinent - it is a very good question. It just doesn't have a simple answer.
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Unfortunately for students of quantum physics this is only the easy part.
Schrodingers equation of 1926 is a wave theory of mechanical particles (of Newtons second law, to which it reduces as it must for large distances and
masses, m x^2/t>>Plancks constant). But this constant came about twenty odd years earlier in a completely different problem - in Einstein giving
particle characteristics to waves, that is light. So we now needed a particle theory of waves.
Dirac did this in 1927 by quantizing (doing a Schrodinger to) Maxwells equations which describe light, by giving the waves particle characteristics
satisfying an uncertainty relation. Their wave characteristics were retained in the same way as Schrodingers particle waves have particle
characteristics. Heisenberg was impressed by this enough to say he could never compete with it.
So Schrodingers equation describes wave particles (things that at large scales seem particles but at small scales are waves. Diracs quantization
describes particle waves (things that at large scales seem waves but at small scales are particles), whose number is quantized. What about particle
waves - why is their number not quantized?
At first this seems unnecessary since if you have two electrons say - they stay two electrons. But that is only at small energies. Relativity means
particles can be created out of nothing - so the great blow is that if you combine the two you have an infinite number of particle theory without ever
wishing for it.
A new round of quantization, called second quantization, was needed on Schrodingers particles, of which his equation turned out to be only an
approximate - non quantized version.
The resulting theory - QFT had many problems - some still persist, cant be solved exactly, or even estimates of errors given. But its been
successful, and is where we are today.
Incidently Schrodinger originally wanted to write a relativistic quantum equation. But saw that it immediately lead to an infinity of particles,
infinite integrals, and put it away
[Edited on 15-5-2009 by len1]
|
|
woelen
Super Administrator
Posts: 8014
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Jgourlay, I think that the best answer to this question is not a matter of trying to explain the (incredibly complicated mathematics and physics) of
(sub)atomic systems, but trying to explain somewhing about human intuition, which is based on human experience.
In daily life we observe the world in a certain way. Based on everyday observations, we build up an 'intuitive model' in our brains, and we use that
model all the time implicitly (we do not actively perceive that we use it) to predict things and to understand things.
Our observations are limited to macroscopic observations at low speeds. All other things we NEVER see, and hence they are beyond our experience and
for that reason beyond our imagination.
A nice example is our implicit model that velocities can be added linearly as 3D vectors. We use that model all the time (e.g. estimating whether it
is safe to cross a street while a car is coming while at the same time you are driving a car on a street which crosses the other street). Imagine that
you were living in a world where velocities always are in the order of 2/3 of lightspeed or even higher. Then you cannot add velocities anymore. The
more general thing (in one dimension) is w = (u+v)/(1+uv/c^2), where w is the relative speed between two objects, moving at speeds u and v. For
velocities u, v much smaller than c, this is VERY close to w = u+v and hence our intiutive model says that this is always the case. We would miserably
fail in a world where velocities are much higher and we would be like babies again when we had to survive in such a world without having accidents all
the time. A little child has to learn what is safe and what is not and we would have to learn that again in a world where ultra high-speed travel is
normal.
A similar problem exists for the ultrasmall world, where particles are not well-determined objects, but fuzzy things, which can overlap without
colliding and that kind of things. If we would see such things in our daily life all the time, then our 'intuitive model' would incorporate such
things and we would have no problems with it, but because we never see such things in our daily life, they are very weird and counter-intuitive for
us.
So, I would say to your son that for such very small particles the world looks totally different and that the things which we find normal do not apply
in that world and that we are bad at handling and understanding this, simply because we never see anything from that world. You can also say that
there is a language called 'mathematics' which describes such worlds, but that this language is not something we can see but only something which
allows us to compute and predict things. The language gives us more abstract understanding, but not more intuitive understanding and that makes
communication of these concepts to laymen so extremely hard.
[Edited on 15-5-09 by woelen]
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
The original question topic had exhausted itself when it received a simple answer at the start of the thread (yes, they do 'bump' into each other, but
can not mutually annihilate). The rest of the thread has been about quantum mechanics.
|
|
kmno4
International Hazard
Posts: 1497
Registered: 1-6-2005
Location: Silly, stupid country
Member Is Offline
Mood: No Mood
|
|
Electron and proton cannot anihilate because e is not antiparticle for p (and vice versa).
There is simple path for joining proton and electron:
p+e -> n+neutrino(e)
Lepton and baryon numbers are conservated in this process.
It requires additional energy - it is easy to see it by comparing sum of masses of proton and electron with mass of neutron.
Of course, this is not the only way of p-e interacting at high and very high energies.
Hydrogen atom is the only "thing" made from p and e which is stable in our room temperature world
Besides - has not anybody heard about K-capture ??
It is evident example of electron capture by (proton in) nucleus.
[Edited on 16-5-2009 by kmno4]
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Yes well here you go. Whats too complicated for someone is too simple for someone else.
Electrons can get captured by protons and all sorts of reactions conserving Baryon numbers are possible. BUT theres not enough energy in the hydrogen
atom for these to be real processes - e- p+ is the lowest energy state. Nevertheless they all occur - virtually - in the atoms, and contribute an
invisibly tiny correction to the mass of the hydrogen atom.
|
|
franklyn
International Hazard
Posts: 3026
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline
Mood: No Mood
|
|
"- if the negative electron and positive proton are attracted, how come the electron
acts like a planet around the sun? How come they don't bam into each other?"
Oh but they do, the result is a neutron. But you need a whole lot of gravity
to overcome the excess energy of the electron which serves as the referee
keeping them apart. An experiment to show this would be to try to stick
two magnets together ( poles opposing so that they repell ) using double
sided adhesive tape. Good luck.
A neuron free of an atom or neutron star will decay in about 905 seconds,
on average, turning back into a proton and electron. Its important to realize
that a neutron does not contain a proton or electron, those are just it's
decay products. The Bohr model of the atom ( solar system analog ) is a useful
mnemonic fiction to keep things organized in thought and do not realistically
represent atomic objects. Particles are just organizations of energy, sort of like
a holler, a gunshot, or a violin tone. When you hear them all together do they
bam into each other ?
Particles actually refuse to be pinned down in any defined place and time, and
are forever in a transitional state between being over here and somewhere else
over there. Uncertainty is a fundament of reality.
When you flip a coin you do not know what the result will be except it can be
either the head or the tail . If you do know what a result will be ( because you
have chosen a result as you do in a wager ) then you do not know when this will
occur, it may be the first flip or not, second or third and so on until the chosen
result is seen. You can know when there will be a result ( most of the time ) but
you will not know what the result will be, or else you can know the result, you
just won't know when it will occur. It is impossible to know both together.
If you could then you would be master of space and time and pantocrator
of the universe - sort of like an investment banker, reality notwithstanding.
This would raise other troubling questions such that you can only really
know of a future event if in some sense it already exits. That would
circumscribe free will to a notional illusion where everything plays out
its role, part, or function as if it were a wind up toy in a movie, one
cannot do otherwise, even contemplate the idea unless it is already
on the film to be played out.
Anyway one must not simpify too much, if the answer to a question
becomes too simple, you might become a Noble Laureate.
P.S.
A wise man , Jacob Bronowski , once said :
" ask an impertinent question , and you are on your way to the pertinent answer. "
Quote: Originally posted by jgourlay | Wow....okay. Serves me right for asking impertinent questions!
[author=Magpie]I don't think your question was impertinent - it is a very good question. It just doesn't have a simple answer. |
useful sites
http://web.jjay.cuny.edu/~acarpi/NSC/3-atoms.htm
http://www.colorado.edu/UCB/AcademicAffairs/ArtsSciences/phy...
HERE IS THE RESOURCE
http://www.colorado.edu/UCB/AcademicAffairs/ArtsSciences/phy...
Click " Electron Orbits " it's this one below
http://www.colorado.edu/UCB/AcademicAffairs/ArtsSciences/phy...
Move the mouse SLIGHTLY as you click the empty space surrounding the red " proton " to create the
electron and give it a lateral motion. Left or right it doesn't matter. It does get crowded after a few.
DeBroglie Wave concept is also useful - Click on the circumference of the circle and drag to change diameter
http://www.colorado.edu/UCB/AcademicAffairs/ArtsSciences/phy...
|
|
franklyn
International Hazard
Posts: 3026
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline
Mood: No Mood
|
|
A neat summatiion of contemporary field and particle physics
- A T O M - Illusion of Reality
http://www.ninjavideo.net/video/8752
click " Download " at the upper left of the view screen
to download the whole file or else watch it in your browser instead.
This is a huge 550 MB high definition avi video
You may need to first install Ninja video's java applet, I don't know.
.
|
|
franklyn
International Hazard
Posts: 3026
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline
Mood: No Mood
|
|
U P D A T E
- A T O M - Illusion of Reality
http://video.google.com/videoplay?docid=-1406370011028154810...
.
|
|
zed
International Hazard
Posts: 2283
Registered: 6-9-2008
Location: Great State of Jefferson, City of Portland
Member Is Offline
Mood: Semi-repentant Sith Lord
|
|
We don't know what electrons and protons really are. We know they like each other, and they like to be close, but not too close. Not unlike your
mommy and daddy.
This is a good thing. If the proton and the electron melded together....The Universe as we know it, would cease exist. Just like our family would
cease to exist, if mommy and daddy were confined together for a long time in a very small space. Like this house.
That is why....You are going to clean your room, and I am going to mow the lawn. And then, the two of us are going fishing.....While your mom does
whatever it is she does, when she isn't burdened by our presence.
[Edited on 2-6-2010 by zed]
|
|
Rich_Insane
Hazard to Others
Posts: 371
Registered: 24-4-2009
Location: Portland, Oregon
Member Is Offline
Mood: alive
|
|
I'm no expert on quantum mechanics, but here's my $0.02
The electrons orbit far away from the nucleus at very high speeds. Now think about riding a bike. The reason you don't tip over when you turn the
street is because you are going so fast that that force is keeping you up against gravity. Now back to the electron. it is moving in a random orbit at
enormous speeds in its shell. The attraction to the proton is kind of like gravity. That speed allows the electron to move around so fast that it
overcomes the attractive forces between + and -.
Again, that's just my idea.
|
|
jaisachdeva
Harmless
Posts: 2
Registered: 4-6-2010
Member Is Offline
Mood: No Mood
|
|
reply to your ques
I think suggest you to put two ball in a transparent plastic cup and seal the top of cup using a similar inverted cup by taping the two, then rotate
the model, balls will stick to walls. Tell the child that force due to which balls are sent outwards is cancelled by normal reaction from the cup base
and which can be assumed to be as the attractive force of between proton and electron.
|
|
lol
Harmless
Posts: 16
Registered: 22-7-2010
Location: i'm from holland
Member Is Offline
Mood: No Mood
|
|
they arent attracted...they basically float in space as the proton expands and pushes them out
|
|
Hoveland
Harmless
Posts: 20
Registered: 20-7-2010
Member Is Offline
Mood: No Mood
|
|
The truth is that scientists do not really know the answer. They have equations to describe particle interactions, and these equations describe two
unsymetric waves that do not annhilate eachother.
More complex, is some speculation by physicists that the subatomic particles are themselves composed yet smaller point-like constituents, which for a
variety of reasons cannot be freed from their subatomic particles. The existence of quarks is already accepted theory, but more controversial is the
theory that electrons are composed of 2 or 3 smaller constituents. Some of this is relative of course. In particle colliders at extremely high
energies, electrons have smashed into X-rays, revealing a quark substructure inside the photon.
From the point of reference of the electron, the photon is the only particle that is moving, and it is a photon, it is greatly blue-shifted, so much
so that it has the (relative) mass of a proton. The uncertainty principle, in this case, allows high probability of finding quarks. High frequency
translates into high rest-mass particles. This, of course, is not implying that photons actually contain quarks, just that energy and matter is very
interchangeable. Many physicists suspect a microstructure for photons, that would explain spin and polarization (did you know photons can be
circularly and elliptically polarized, as well as have a separate property of angular momentum, which comes in quanta (hbar) ?
http://www.icfo.es/index.php?section=research4&lang=engl...
Another bit of insight, it may be that there can never be any true annhilation into nothingness, because any sudden point of zero energy would "cut
the string" - the particle's path through space and time. The string is theorized to snap back like a rubber band, leaving only the continuous strings
left to exist in our present space and time.
[Edited on 29-7-2010 by Hoveland]
|
|
psychokinetic
National Hazard
Posts: 558
Registered: 30-8-2009
Location: Nouveau Sheepelande.
Member Is Offline
Mood: Constantly missing equilibrium
|
|
Quote: Originally posted by lol | they arent attracted...they basically float in space as the proton expands and pushes them out |
Whoops, all my electrons fell off.
“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found
the object of his search.
I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.”
-Tesla
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Good to see they now have internet access in the mental hospital
|
|
lol
Harmless
Posts: 16
Registered: 22-7-2010
Location: i'm from holland
Member Is Offline
Mood: No Mood
|
|
|
|
psychokinetic
National Hazard
Posts: 558
Registered: 30-8-2009
Location: Nouveau Sheepelande.
Member Is Offline
Mood: Constantly missing equilibrium
|
|
Because they're married.
“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found
the object of his search.
I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.”
-Tesla
|
|
len1
National Hazard
Posts: 595
Registered: 1-3-2007
Member Is Offline
Mood: NZ 1 (goal) - Italy 1 (dive)
|
|
Because they are not married and catholic I think you meant
|
|
psychokinetic
National Hazard
Posts: 558
Registered: 30-8-2009
Location: Nouveau Sheepelande.
Member Is Offline
Mood: Constantly missing equilibrium
|
|
Maybe that's where neutrinos come from.
“If Edison had a needle to find in a haystack, he would proceed at once with the diligence of the bee to examine straw after straw until he found
the object of his search.
I was a sorry witness of such doings, knowing that a little theory and calculation would have saved him ninety per cent of his labor.”
-Tesla
|
|
peach
Bon Vivant
Posts: 1428
Registered: 14-11-2008
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by watson.fawkes | The thing to teach is that models are approximations to reality, not generators of reality, and that every model has some non-universal realm of
applicability. |
You would not believe the amount of time I had to spend, unsuccessfully, trying to explain that concept to my older brother (who would most definitely
claim to be scientifically, Dawkins oriented (ironically brainwashed into belief)) when trying to discuss the idea of how higher deminsional
spaces predict and then explain interactions at the quantum level.
"But has someone actually BEEN to these dimensions yet!?"
"That's NOT the point..."
I tried multiple methods. There are some people who don't seem to 'get' the idea that it's not necessarily a solid, tangible thing that exists in
reality, merely that 'reality' behaves in a similar way and can be described by the models.
There are others, often the mathematically minded, who excel at this way of thinking. Electronics engineers work with what are essentially black box
(tiny, tiny, tiny black boxes), where one thing goes in one side and something else comes out the other. There is clearly a very different mindset at
work.
I ended up giving him a book on superstring theory as he stormed out of the room. What confused me about my brother is his firm belief in things like
evolution and standard nuclear physics, yet inability to take a not very large step beyond that to quantum mechanics and the string model (and no, he
doesn't know about alternatives like super gravitational field theory, so that's not why).
I tried pointing out that this maths has not only predicted the groups of quantum particles, but the missing ones as well, which have then been found
and then explained using the same rules. I also tried likening this to the more basic laws of physics which model kinetic behaviours at the tangible
level. Or the way Mendeleev left spaces for elements we've now found (darn smarty old chap). I said clearly, many times, that they may not actually be
places you can go to, just that they're required by the maths that predicts the interactions in the lower dimensions.
The two never joined up.
I used to be a millitant athetist. Then realized, I could churn out any shit I felt like and say it was quantum mechanics and easily convince a lot of
atheists it was correct, due to their own belief that anything sounding scientific nowadays is the utter truth. Which is the point where I began to
take sides with the religious, if only to duly annoy the atheists. Indeed, they believe so even more than I. When I read a journal or model, I start
off assuming it's incorrect, then wait for it to prove it's self correct; an unfortunately pessimistic view on things, but one that means your mobile
phone works. A worrying majority of people now assume it's all correct, to the degree of expecting models to be solid, tangible objects. Then they
have an episode when it goes beyond that, and is proving it's self to be correct; like higher dimensional (ethereal other domain) string theory.
In my brother's case, he routinely goes on about how his job is harder than anyone else's (as everyone does, even porn stars). He hates the idea of
someone knowing something he doesn't. Which I suspect is the grounds for his hatred of the idea of higher dimensional models that hint at something
beyond the Dawkinesque, solid way of life.
[Edited on 4-8-2010 by peach]
|
|
watson.fawkes
International Hazard
Posts: 2793
Registered: 16-8-2008
Member Is Offline
Mood: No Mood
|
|
I've been there. I go there all the time. I travel there with my
imagination.
|
|
Pages:
1
2 |