## General Question

Asked by dotlin (419) August 10th, 2010

Someone I know online was saying you can cut things to infinity, he said even an electron has a left and right side therefore it can be halved.

The person replying has a extensive knowledge in physics said this.
“No. A standard electron is a point particle. A POINT.

points do NOT have sides, or widths, or lengths.”

If this is the case how can millions of inadvisable points make width if 1 has none?

Observing members: 0 Composing members: 0

I did ask was width made from the distance between points but that still leads me to so many other questions, I just need time to think about it.

dotlin (419)

I’m not sure about an electron being a point particle. That would imply it’s some kind of singularity like a black hole, and that seems strange. We often assume it to be a point mass/charge in calculations for the sake of simplicity/because we don’t know any better.

In any case, if it is, the reason why millions could form an object that has a definable length is because electrons produce electromagnetic fields, due to the fact that they are charged particles, which do have a measurable size. Essentially, the shape of an object is defined by the combined electromagnetic fields of all its constituent subatomic particles,

chocolatechip (2999)

Wiki says that electrons are considered to be an elementary particle, since they have no known subcomponents. They do have mass, if that helps any.

My guess is that both of your friends were oversimplifying without realizing it.

This reminds me of… oh, who was it? Ah! Zeno!. Parmenidies may hold the insight that you seek.

This question is older than you think. :D

Nullo (21934)

@Nullo
Yeah is was going to bring Zeno into it but the person replying already did before I had a chance.

dotlin (419)

@dotlin I’m glad to hear it. Them classics need airing now and then.

If you ask me, this is the sort of navel-gazing that won’t ever yield a working answer, nevermind how many black hole generators we build or GDPs-worth in funding we pour in. Thankfuly, we have a sufficiently accurate idea of how electrons work.

Nullo (21934)

How can two points with no length, depth or width interact with each other on those scales? Or am I misunderstanding the concept of detention with position?

But if two lines were heading flat towards each other as their ends have no depth they would never interact so ow do elementary particles interact?

dotlin (419)

Gravity and electric charge both come to mind (though gravity likely has precious little to do here). The suckers have mass, and they have a charge. And unless I’ve forgotten more than I think that I have, they do business with protons, which are a good deal larger.

Nullo (21934)

Elementary particles (and by extension, all objects composed of these particles) interact by means of forces like gravity and electromagnetism.

Remember that matter never actually “touches” other matter. Any interactions between matter are all via elementary forces.

chocolatechip (2999)

@chocolatechip
That’s what I said on another website is it not the particles interacting and well pretty much what you were saying.

dotlin (419)

Actually, a muon neutrino has ⅓ the mass of an electron.

LuckyGuy (35616)

Electrons are point-like.

Another way to think of electrons is that they don’t “exist” in the sense we’re familiar with. At any given moment, an electron only has a probability of existing at a certain place.

Qingu (21160)

I don’t know if an electron is a point (i.e. no sides, or length dimensions). How much space it occupies is (apparently) irrelevent if its safe to assume its a point though.

Either way, width (or any other 2 dimensional measurement) is by its nature the distance between two points. Those two points preferrably have no spacial dimensions. The Millions of these electrons which form the width dimension are NOT touching each other, there is space between them. in fact it is the space between them which your measureing.

1 million electrons 1nanometer apart = 1meter
1 million electrons touching each other = 0m (if they are assumed to be a point)

jahono (145)

Mathematically, millions of points “put together” still yield zero length. When points are arranged along the real line, any finite interval of it, no matter how small, contains an uncountably infinite set of points. One can also construct subsets of the real line that are uncountable but have measure zero, however (ex: Cantor’s middle-third set).

Experiments at SLAC showed years ago that protons had internal structure (what turned out to be quarks). No experiments (to my knowledge) to date have revealed any internal structure of electrons, but there are practical limits to our ability to probe short length scales.

Quantum physics says that electrons are not points but a cloud with both wave-like and particle-like properties. It suggests that all matter is, in fact, so thinking of a subatomic particle as a 0-dimensional point is slightly off.

I common idea among string theorists is that electrons, protons, neutrons, quarks, and all other matter is made of tiny multidimensional “strings”. These strings can only be seen if you were to shrink to the billionths the size of an electron. However, this area is strictly theoretical, so I won’t go any further.

It seems I can’t answer a question on Fluther without mentioning quantum physics. :) It’s just me I guess.

Vortico (3123)

Electrons may not be points, but tiny vibrating strings.

Rarebear (25144)

All physical evidence up to the present implies that electrons and quarks have point-like properties. That is, no experiment has shown any further structure or extent. So in that sense they are point-like. According to the Standard Model, it makes no sense to speak of an electron “cut in half” or having “sides.”

That said, there are speculative theoretical models (string theories & such) in which particles I mentioned above might actually have very fine structure in the form of higher-dimensional, incredibly tiny vibrating “strings”. This would occur at such a small scale, however, that no evidence is conceivable using any known form of technology.

So for now, physicists are secure in declaring that electrons & quarks are point-like. You might have to wait a few centuries to learn any different…

gasman (11291)

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