• Quick note - the problem with Youtube videos not embedding on the forum appears to have been fixed, thanks to ZiprHead. If you do still see problems let me know.

Ten Scientists Commit Suicide!

Not really.

Well, I was referring to the (well deserved, IMO) lambasting they recieved for their so-called "science by press conference", rather than waiting for peer review and such.

I thought that pretty much ended it for them, but I accept that I haven't really researched the facts of what happened to them afterward, as my goal was humor over accuracy :)
 
if you allow the electrons to have some volume why shouldn't they take up the entire atom, or at least a large part of it?
If you work out how much space (whatever that means) could be taken up by the electrons of a heavy element like Radon, then for lighter elements, like Neon, there would still be lots of room between the electrons unless the Neon electrons were bigger than the Radon ones.
 
Anybody ask for the names of the scientists yet? I wonder if that will make the little claimant think for a second.
 
Err, no. The fact that it was a thin piece of gold showed that there wasn't much stuff there (Avogadro's number was worked out before Rutherford's experiment). The observation that this thin piece of gold would occasionally cause the particles to rebound completely indicated that what positively charged stuff was in there was concentrated into an incredibly small volume. The analogy is "imagine firing cannon balls at tissue paper, and seeing one bounce back at you".

Of course, even knowing that the positively charged particles are in a small fraction of the atom's volume doesn't say the atom is mostly empty. If you assume electrons are points with no volume, then you have the problem that 'voluminous' objects don't exist (unless you imagine that electrons are points but protons aren't, which seems like a very odd thing to imagine, in my opinion), and if you allow the electrons to have some volume why shouldn't they take up the entire atom, or at least a large part of it?

Well my understanding was that protons being so different in their nature from electrons do have some size. Of course you might be able to argue that he components of the proton do not have size themselves. Kind of like a atom has a size, but the components do not.

I am not quite versed in the details of the standard model to say that clearly about this issue. Wikipedia does list a size for a proton but not an electron.

Ah I was right about electrons being a fundamental partical while protons are not as they are made up of quarks

see

http://en.wikipedia.org/wiki/Electron
http://en.wikipedia.org/wiki/Proton
 
If you work out how much space (whatever that means) could be taken up by the electrons of a heavy element like Radon, then for lighter elements, like Neon, there would still be lots of room between the electrons unless the Neon electrons were bigger than the Radon ones.

Allright, I'll guess that the greater field from a heavy nucleus compresses the volume of the electron. Sounds reasonable enough to me, as much as I can guess what reasonable would be for subatomic phyiscs in 1910.

ponderingturtle, I'm just attempting to imagine what scientists could have thought about the atom after Rutherford's experiment. I think that by the time scientists learned about quarks quantum mechanics muddled up discussions about the volume of electrons so that asking about the volume is somewhat pointless (though I wouldn't be surprised to learn I'm wrong).
 
Allright, I'll guess that the greater field from a heavy nucleus compresses the volume of the electron. Sounds reasonable enough to me, as much as I can guess what reasonable would be for subatomic phyiscs in 1910.

ponderingturtle, I'm just attempting to imagine what scientists could have thought about the atom after Rutherford's experiment. I think that by the time scientists learned about quarks quantum mechanics muddled up discussions about the volume of electrons so that asking about the volume is somewhat pointless (though I wouldn't be surprised to learn I'm wrong).

Well the atom would have been under much discussion, but basicly they would have thought it had a small charged core instead of a difuse postively charged media as was previously thought to be the case. It would not have been until the discovery of the proton and the idea that there was things that made up nucleous and such that changed things.
 
ponderingturtle, I'm just attempting to imagine what scientists could have thought about the atom after Rutherford's experiment. I think that by the time scientists learned about quarks quantum mechanics muddled up discussions about the volume of electrons so that asking about the volume is somewhat pointless (though I wouldn't be surprised to learn I'm wrong).

We know what they thought:

http://en.wikipedia.org/wiki/Rutherford_model

http://en.wikipedia.org/wiki/Bohr_atom
 

Neither theory, as far as I'm aware, says much about the structure of electrons, whether it's point or a volume. The Bohr model could place a limit on the size it can occupy and still have it's centre of mass appropriately positioned so the angular momentum works out (assuming you don't allow oddly shaped mass distributions), but I don't see anything in the theory that would say atoms are mostly empty space.
 
Neither theory, as far as I'm aware, says much about the structure of electrons, whether it's point or a volume. The Bohr model could place a limit on the size it can occupy and still have it's centre of mass appropriately positioned so the angular momentum works out (assuming you don't allow oddly shaped mass distributions), but I don't see anything in the theory that would say atoms are mostly empty space.

electrons where known to be close to an effective point particle before that. The rutherford experiment showed that the positive material in an atom is also highly concnetrated. Between them you can see that most of the volume in an atom is not occupied by any particle.

The rutherford experiment does show that atoms are mostly emty space because it shows that their mass must be highly concentrated in one place or you would not get the rebound of the alpha particle. You know the mass and energy of the alpha particle and to rebound like that it needs to hit a highly concentrated mass as well. This has to be small or most of them would not pass through uneffected.
 
electrons where known to be close to an effective point particle before that. The rutherford experiment showed that the positive material in an atom is also highly concnetrated. Between them you can see that most of the volume in an atom is not occupied by any particle.

I don't see how that follows. Electrons were known to be quantized and less massive compared to the rest of the stuff in the atom, but I don't see how that's evidence that they have an extremely small volume.
 
This sounds like an inflated, overwrought version of a rather cute story told by Loren Eiseley, in The Firmament of Time, even then cited as a "legend" among scientists, about a physicist who in his dotage took to wearing enormous floppy slippers to forestall the possibility of falling through the interstices of matter.

The pulsing rivers of his blood, the awe-inspiring movement of his thoughts had become a vague cloud of electrons interspersed with the light-year distances that obtain between us and the further galaxies. This was the natural world which he had helped to create, and in which, at last, he found himself a lonely and imprisoned occupant. All around him the ignorant rushed on their way over the illusion of substantial floors, leaping, though they did not see it, from particle to particle over a bottomless abyss. There was even a question as to the reality of the particles that bore them up. It did not, however, keep insubstantial newspapers from being sold nor insubstantial love from being made.
 
I don't see how that follows. Electrons were known to be quantized and less massive compared to the rest of the stuff in the atom, but I don't see how that's evidence that they have an extremely small volume.

Known to be quantized? This is before the bohr model, indeed that is a reaction to this as the plum pudding model didn't work any more so you could not have electrons hanging out in a decentralized positively charged medium. This was around the time that the charge was measured and such. You seem to be incorperating discoveries made as a result of the Rutherford experiment as being already known.

OR did you mean electrons where known to be individual particales, that is about fundamental as well.

I don't understand what you are trying to say, would please state your position clearly.
 
Known to be quantized? This is before the bohr model, indeed that is a reaction to this as the plum pudding model didn't work any more so you could not have electrons hanging out in a decentralized positively charged medium. This was around the time that the charge was measured and such. You seem to be incorperating discoveries made as a result of the Rutherford experiment as being already known.

OR did you mean electrons where known to be individual particales, that is about fundamental as well.

I don't understand what you are trying to say, would please state your position clearly.

I ment electrons were known to have a fixed quantity of charge, rather than being infinitely divisible.
 
I ment electrons were known to have a fixed quantity of charge, rather than being infinitely divisible.

That comes with the idea of them being particles. Once you define an electron then at least charge based on electrons must be descreet as you can only have a descreet number of electrons.

There relative size would have been shown to be small in experiments with cathode rays and the like(which is where they where discovered). The plum pudding model was based on the idea that electrons are much smaller than atoms, and are just kind of sitting there like nuts in a plumb pudding. The Rutherford experiment showed that while atomic size is pretty big it is almost entirely empty. So that certain information about the size was well known or readily measureable from this.

I think avogaldro's number was known and you can get a fair idea about molecular size through a few experiments with oil slicks and such.

So the relative sizes where at least understood if not as dirrectly measured as we have done them now.
 
That comes with the idea of them being particles. Once you define an electron then at least charge based on electrons must be descreet as you can only have a descreet number of electrons.

Yes they're discrete, but it seems to me they could still be volume charges.

There relative size would have been shown to be small in experiments with cathode rays and the like(which is where they where discovered).

Unless there was an amazing experiment I missed, cathode ray experiments only showed the electrons had a charge to mass ratio of some value. Milikan's oil drop experiment then determined the charge, and that allowed calculation of the mass, which they found to be a small part of an atoms mass. But I'm not aware of any experiment that measured a spatial size of electrons. There are semiclassical electron sizes, and I don't think any of them are based on experiment, and I'm not too sure anyone really believed they were true.
 
Yes they're discrete, but it seems to me they could still be volume charges.



Unless there was an amazing experiment I missed, cathode ray experiments only showed the electrons had a charge to mass ratio of some value. Milikan's oil drop experiment then determined the charge, and that allowed calculation of the mass, which they found to be a small part of an atoms mass. But I'm not aware of any experiment that measured a spatial size of electrons. There are semiclassical electron sizes, and I don't think any of them are based on experiment, and I'm not too sure anyone really believed they were true.

Classical electron radius was never meant to be an actual size of an electron, it merely chracterises certain interations with other particles. It is called the electron "radius" because it is defined in the same way as the real radius of other particles (hydrogen atom for example).

Higher energy particles have shorter wavelengths and so allow smaller particles to be investigated. So far there is evidence that protons and neutrons are made of quarks, and it has been suggested that quarks may be made of smaller particles, which should show up in experiments at the LHC and ILC in the next few years. Electrons are even smaller than this, so even if they do have a finite size, it will not be possible to test this until much more powerful accelerators are built.
 
I asked for details, but before I got an answer (if indeed one was forthcoming), the thread was locked, then deleted, then I was banned.

Yeah. Quickest way to get banned is to show you need more information instead of happily swallowing garbage and contributing more to show team spirit.

I once got banned for asking "How is polio natural to gut flora??".
 
I am sure that her professor said exactly that, and that he was being hyperbolic.

Had he said, "They all did back-flips over the discovery," Little Miss Dim would have taken that literally too.
 

Back
Top Bottom