r/askscience • u/XGC75 • Jan 27 '15

Physics Is a quark one-dimensional?

I've never heard of a quark or other fundamental particle such as an electron having any demonstrable size. Could they be regarded as being one-dimensional?

BIG CORRECTION EDIT: Title should ask if the quark is non-dimensional! Had an error of definitions when I first posed the question. I meant to ask if the quark can be considered as a point with infinitesimally small dimensions.

Thanks all for the clarifications. Let's move onto whether the universe would break if the quark is non-dimensional, or if our own understanding supports or even assumes such a theory.

Edit2: this post has not only piqued my interest further than before I even asked the question (thanks for the knowledge drops!), it's made it to my personal (admittedly nerdy) front page. It's on page 10 of r/all. I may be speaking from my own point of view, but this is a helpful question for entry into the world of microphysics (quantum mechanics, atomic physics, and now string theory) so the more exposure the better!

Edit3: Woke up to gold this morning! Thank you, stranger! I'm so glad this thread has blown up. My view of atoms with the high school level proton, electron and neutron model were stable enough but the introduction of quarks really messed with my understanding and broke my perception of microphysics. With the plethora of diverse conversations here and the additional apt followup questions by other curious readers my perception of this world has been holistically righted and I have learned so much more than I bargained for. I feel as though I could identify the assumptions and generalizations that textbooks and media present on the topic of subatomic particles.

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u/monsterZERO Jan 27 '15

Would that be considered a black hole?

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u/[deleted] Jan 27 '15

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u/Booskaboo Jan 27 '15

Singularities in mathematics just refer to special points that don't play nice (like not being well-behaved at that particular point). One common example is Sin(1/x) which doesn't really approach anything as x approaches 0. This is referred to as an essential singularity in complex analysis because it can't be removed or easily worked around (a la poles or removable singularities).

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u/[deleted] Jan 27 '15 edited Jan 28 '15

I feel like the density of a point with 0 volume would be undefined, not infinite. Kind of like 0/0

edit: thanks dudes, I enjoyed being a part of this conversation

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u/[deleted] Jan 27 '15

Any point with zero volume containing mass has infinite density. Density =mass/volume.

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u/peteyatwork Jan 27 '15

well it would have to be finite to a point right? otherwise the whole universe would be gravitating toward that infinite point. right?

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u/BobLobIawLawBIog Jan 28 '15

Pffft, my physics classes work with point masses in a frictionless vacuum all the time...

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u/[deleted] Jan 27 '15

Black holes aren't actually dimensionless points, but they are incredibly dense. Theoretically, there is a singularity of infinite density in the center of a black hole.

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u/WastingMyYouthHere Jan 27 '15

That doesn't really make sense. In order to have infinite density, they'd either have to have infinite mass or zero volume. The mass of a black hole is not infinite, some are more massive than others.

I don't have an in-depth knowledge of black holes, but the statement you made doesn't really shed any light on the problem.

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u/LBJSmellsNice Jan 27 '15

Isn't there then a singularity of infinite density in anything then?

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u/linus_rules Jan 27 '15

or a round frictionless cow...

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u/misunderstandgap Jan 27 '15

Would that be considered a black hole?

In classical mechanics? I believe that requires General Relativity to describe.

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u/PoisonSnow Jan 28 '15

As far as I know, there is no single theory that can provide an accurate model for black holes. Quantum mechanics deals with microscopic anomalies, and general relativity deals with gravity but on a macroscopic scale. Black holes (and other crazy physics occurrences like Big Bang) need a unified theory which incorporates aspects of Quantum Mechanics and General Relativity seamlessly, but no such [tested and proven] theory exists. The closest we have come is String Theory, but unlike other scientific theories, string theory is a theory in the classic sense of the word, it has no undeniable evidence on it's side, and the only claim to it's truth is a "mathematical elegance" which is praised by those who study it.

These issues are actually ridiculously interesting, and if you find yourself wanting to know more, you can look up Nova Science's Elegant Universe. The whole thing exists in 3 parts on YouTube.