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by antonvs 1 day ago
Every particle type has its own field, but the OP article is counting a single particle type multiple times based on properties like spin and polarization. At one point the article reaches the number 118. That corresponds directly to 37 quantum fields once you take the "double counting" into account.
2 comments
someoldgit 7 hours ago
Should the quantum vacuum / zero-point field(s) be counted as well?
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antonvs 3 hours ago
No, that's just the vacuum state of any of the standard quantum fields.

"Field" is being used there in its general sense, of a quantity that has a value for every point in space and time. It's saying that in a (region of a) quantum field that contains no activity, there are nevertheless random fluctuations, which can themselves be modeled as a field. But they're not separate from the quantum field that gives rise to them - they have all the same fundamental properties.

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dpark 1 day ago
Where are you getting 37? The standard model has 17 fields.

If you pick and choose which properties to select as unique fields, maybe you can get the number 37, but at that point why not 118 fields?

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antonvs 1 day ago
> The standard model has 17 fields.

Without qualification, that's false. 17 is a simplified or compressed view of what the Standard Model describes. I gave more detail in this comment:

https://news.ycombinator.com/item?id=48700610

37 is what you get from counting Dirac matter fields (24) plus gauge fields (12) plus the Higgs. That's post-symmetry-breaking, and doesn't account for chirality.

If you count fundamental field components in the electroweak-symmetric Lagrangian, you get 43. I broke down both of those numbers in my comment linked above.

> If you pick and choose which properties to select as unique fields, maybe you can get the number 37, but at that point why not 118 fields?

There's no picking and choosing involved - quite the opposite. It's counting what the QFT math specifies. Particles with e.g. different color charges can't share the same field. To get to 17 from either of the above, you have to ignore quark color charges and the different gluon types. It's essentially a classification of types of particles that combines field together, it's not a count of fields.

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