What is the smallest thing that we know to exist?

[kermit911]

What is the smallest thing that we know to exist? Example: A Cell, Atom, etc...

Kermit911

[Loosehead]

Currently it's a quark (several different "flavours2 of quark exist) although there is a theory that even smaller objects exist called "strings" though they have not been shown experimentally.

[mr_pointment]

makes my hadron seem even larger lol

[fo3nix]

technically, (i'm being very pedantic here), the electron is the smallest thing found.

the quark as loosehead would be the smallest, but one has never actually been found (because a single one can never exist on its own). it's just a theory that works very nicely, and so is accepted in particle physics as being real.

[theren_911]

Damn I'm dumb, I thought "Quark" was a little alien with gigantic ears...

[Loosehead]

They exist in pairs but they are known as individual items, up, down, charm, strange, top, bottom. They are well accepted in physics,ok you get 2 shoes in the box but you accept the existance of each individually.

Pedantic? nah we need a new word! Tell you what fo3nix you are allowed occasionally, just occasionally to take the easy way and not try and nitpick, ok?

[boobesque]

actually quarks are usually found in triplets. and i have read that electrons near absolute zero can be split in half suggesting that they are made of even smaller particles which would undoubtedly be smaller than the quark. and if we accept theoretical particles like quarks surely p-branes and super strings would be the smallest that we think we know

[mibn2cweus]

There are millions of (times) millions of atoms in a single living cell. By contrast, if the matter (particles) which make up an atom were squished together you could fit millions of millions of them within the space occupied by a regular atom.

[gammaray]

I thought I was the smallest thing known to exist...but I was just very far away!

[fo3nix]

loosehead: well I am just being pedantic, but answering the question correctly. We do not know that quarks exist, no single one has ever been found. It's just a very good theory. though i do think that for a high school/a-level/general knowledge test, quarks would be the correct answer to this question. also worth noting to what i say below is that they are classed as particles in a very real sense.

boobesque: quarks are found in triplets and pairs. pairs are hadrons, triplets are baryons. also, electrons do not split near absolute zero. I believe you're talking about cooper pairs, which are basically just two electrons (a little more than this, though). superstrings are not even things at all yet. string theory is just a big theory; there is experimental evidence for quarks, but none exists for strings. The theory is far from complete too; the standard model that describes quarks is very much a successful theory. Currently string theory is more philosophy or pure mathematics than science.

[druiaghtagh]

Can it go to infinity, when we have the knowledge to discover smaller and smaller things, will it come to a point when you have the ultimate limit ?

[fo3nix]

druiaghtagh: no-one really knows for sure. there exists something called the Planck length, which is really really small (many times smaller than atoms, for instance). One idea in string theory is that this is the level at which you can go down to, and no deeper. This solves one problem, that of the theorised quantum foam. It's a bit of a hack really. but it seems to work.

[Clanad]

If I may, Planck Length (or, more exactly Planck Time) is not a "thing" but a measurement.
Planck time is the time it would take a photon travelling at the speed of light to across a distance equal to the Planck length. This is the �quantum of time�, the smallest measurement of time that has any meaning, and is equal to 10-43 seconds. (Source: Fundamental Physics Constants) No smaller division of time has any meaning. This explains the reason that we can't say, precisely, when the universe began since we can only measure back to 10-43 seconds...

[markja]

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[fo3nix]

clanad: what you say is true, but it's a theory. there may be smaller and smaller scales, there may not.

[mibn2cweus]

markja . . . markja! Pay attention in class! lol

c�> <�? *^* <�) <�)

[Dr Yan]

'Break theorem is in the process of being proved in Poland in July 2006.

When you break someting there is a ''gap.

The smallest part of that gap is the smallest 'item' you can have.

There are 'variations' in the gap so there will be variations in how small you can 'go'.

Break a ruler in half, then half again and so on. Each time you do this the ruler gets smaller because you are running out of ruler. And you will 'run out' of ruler. The ruler 'parts' have gone elsewhere.

When you reach the 'gap' point that will be as small as you can go.

'Gap' measurment is different to 'planck time and length' theory but similar in complexity of understanding.

[jakey pakey6]

i think that the DNA is the smallest thing as its in all life forms