Is there any limit to how small things can be?

[John J. Bannan]

I know scientists like to think there is a limit to how small things can be, but they have never identified such a limit. Although the very existence of defined objects seems to imply a limit - otherwise, how can they be defined? Nevertheless, how can there be a limit in a universe with so many seeminly infinite qualities, e.g. time and numbers?

[alexb123]

Surely you could never produce anything that is made from components smaller than an atom.

[one_raven]

Surely you could never produce anything that is made from components smaller than an atom.

What if the photon is a discrete particle?

[John J. Bannan]

Light is an object in a sense, and is not made of atoms. Besides, I didn't literally mean make some sort of household object. I meant the quality of contrast, i.e. the difference that separates things so that we can claim they exist.

[John J. Bannan]

A photon may be a discrete particle, but it is not indivisible - otherwise light could not travel across the universe without spreading itself out to thin.

[Oli]

I know scientists like to think there is a limit to how small things can be, but they have never identified such a limit.

Really? And how much science have you read?
Try reading up on Planck.

[Oli]

A photon may be a discrete particle, but it is not indivisible - otherwise light could not travel across the universe without spreading itself out to thin.

Quarks?

[John J. Bannan]

Why don't you just tell me what Planck has to say?

[one_raven]

A photon may be a discrete particle, but it is not indivisible - otherwise light could not travel across the universe without spreading itself out to thin.

I don't see how you come to this conclusion.

Quarks?

Smaller than a photon?
I'm not so sure.

[one_raven]

The Planck length, denoted by , is the unit of length approximately 1.6 × 10−35 metres or about 10-20 times the size of a proton. It is in the system of units known as Planck units. The Planck length is deemed "natural" because it can be defined from three fundamental physical constants: the speed of light, Planck's constant, and the gravitational constant.

From Wiki.

[John J. Bannan]

A photon is a particle and a wave. You can't split the particle, but you can divide the wave.

[alexb123]

What do you mean 'discrete partical' I haven't heard of this before?

Also, it is very hard to see why or how something subatomic could be produced the quantam laws are not well understood. If this could happen I would imagine this would be in the very distant future.

[one_raven]

A photon is a particle and a wave. You can't split the particle, but you can divide the wave.

Which makes the particle indivisible, no?

[John J. Bannan]

Thanks. Obviously, if a proton is smaller than the Planck length, then the Planck length is not the smallest indivisible unit.

[one_raven]

What do you mean 'discrete partical' I haven't heard of this before?

A particle existing as a seperate and whole thing.

[one_raven]

Thanks. Obviously, if a proton is smaller than the Planck length, then the Planck length is not the smallest indivisible unit.

I didn't even read that paragraph!

Can someone please clear that up?

[John J. Bannan]

Good question. How can the photon as a particle yet be divided as a wave? Makes me think a photon can be divided.

[Oli]

As the invariant mass of the quark –antiquark pair produced by the photon ...

From http://www.hep.ucl.ac.uk/~jmb/Teachi...-2005/aqsa.pdf

If a photon breaks down into a quark and an anti-quark then it can't be bigger.

The paper is also full of the little phrase (and TITLE) "photon remnants" - the photon is not the smallest thing there is.

[Oli]

Thanks. Obviously, if a proton is smaller than the Planck length, then the Planck length is not the smallest indivisible unit.

Actually one-raven's post came out wrong. Planck length is about 10^-20 times a proton, not 10-20 times... so a proton isn't smaller.
I was actually thinking of Planck time when I first posted - the shortest unit of time.

[one_raven]

From http://www.hep.ucl.ac.uk/~jmb/Teachi...-2005/aqsa.pdf

If a photon breaks down into a quark and an anti-quark then it can't be bigger.

The paper is also full of the little phrase (and TITLE) "photon remnants" - the photon is not the smallest thing there is.

Yes, that's how they interpret the results.