Orders of Magnitude - From Quark to Superstring Theory

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The discussion explores the vast differences in orders of magnitude between the size of the visible universe (~10^25) and quarks (~10^-15), highlighting the significant leap to the Planck length (~10^-33) associated with superstring theory. Participants express curiosity about the apparent absence of intermediate scales and whether there is a fundamental reason for this gap. The Planck scale is considered distant from current physics, leading to speculation about new physics that could bridge this gap, such as supersymmetry or extra dimensions. It is noted that strings are not the smallest known objects, but rather a theoretical framework for potential future discoveries. The conversation underscores the ongoing quest to understand the underlying principles of physics.
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Fascinating looking at the various orders of magnitude (in terms of length), from the size of the visible universe (~10^25) to the size of a quark (~10^-15), and all orders inbetween.

But then I read about Superstring theory and how these strings are at the Planck length, around 10^-33. Why the huge jump from quark to string? Surely there must be loads of "stuff" in-between?

Apologies if this is a daft question!
 
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Surely there must be loads of "stuff" in-between?
Why?
The Planck scale (length, but also all other Planck units) is far away from everything we know. That means there could be something in between, but it does not have to.
 
It doesn't mean it has to, but this huge gap is kind-of odd to me. I wondered whether there was a fundamental reason why there's a huge jump in magnitude before we get to the smallest of the objects we know about.
 
RobinsonUK said:
It doesn't mean it has to, but this huge gap is kind-of odd to me.
It looks odd to scientists as well - and it is one of the reasons why many scientists expect that new physics is not so far away from current physics.
Supersymmetry is one possibility, and extra dimensions can lower the Planck scale.

I wondered whether there was a fundamental reason why there's a huge jump in magnitude before we get to the smallest of the objects we know about.
If there is one, it is not known yet.

Strings are not "the smallest objects we know about". String theory is - even if you are optimistic - a concept how we might get a new theory at some point in the future.
 
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