# Which is smallest distance measurement which makes sense talking about [duplicate]

This might seem a silly question, but here it goes:

Of all possible values for a measure of distance, which is the smallest that makes sense talking about?

I mean, I could talk about $10^{-100000}$ meters but in real life this value is smaller than anything we know (i think), so it wouldn't make any sense talking about this value, now would it? Initially I thought about Planck length, but I'm not sure.

Please not I'm not referring to mathematics, any number can be of use in mathematics. But in real life, small values like $10^{-100000}$ meters don't make sense.

So, what is smallest distance value that makes sense talking about?

Thanks.

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Possible duplicates: physics.stackexchange.com/q/28720/2451 and links therein. –  Qmechanic Feb 6 at 22:27

## marked as duplicate by Brandon Enright, John Rennie, Qmechanic♦Mar 12 at 10:23

According to the generalized uncertainty principle, the Planck length is, in principle, within a factor of order unity, the shortest measurable length – and no improvement in measurement instruments could change that. (Wikipedia)

$$1 \text{ Planck length} = 1.61619926 \times {10}^{-35} m$$

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Thanks. I should have checked that. –  Dayman75 Feb 6 at 23:16
You should note that this is speculative and only holds true for certain physical theories (which remain untested) beyond the standard model. It's better to say that the Planck length is the smallest distance for which our current theories should hold. Physics at scales less than the Planck length is not currently known. –  mcFreid Feb 7 at 13:18
As an engineer I would say $10^{-5}\mathrm{m}$ because for mechanical purposes the smoothest surface finishing does not need to be net as this. As a practical chemist I would say $10^{-10}\mathrm{m}$ is small enough since I will never care about the very real diameter of an electron. I guess physicist would like to get a little bit smaller. Basically speaking, there is, at least, some interesting and energetic Electro Magentic wave with smaller wavelengths ...