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(Although Donald Rumsfeld was mocked for talking about "known unknowns" and "unknown unknowns", I think it's an truly important distinction.)

Periodically, I hear about how the universe might be in a metastable false vacuum and how we might all be toast because of it. But I also realize that there are a lot of known unknowns out there; e.g. we know that normal matter makes up only ~5% of the universe, and we don't really know what's going on with the remaining 95%. That's an example of a known unknown.

If I understand correctly, the calculations to determine if we are in a false vacuum are all based on the standard model of particle physics. However, we also know that the standard model is incomplete. Are there any "known unknowns" about the standard model's limitations that could affect the possibility of a false vacuum?

I realize that there are error bars on the mass of the top quark and higgs boson, and we need to know them to determine if we are in a false vacuum; thus, the exact values of those masses is a known unknown, but that's not what I'm asking about. I'm talking about the possible effect of known, fundamental holes in the standard model.

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I think there is a long list of things we know about but don't understand yet.
For example, we know neutrinos have mass but we don't yet know what those masses are or even exactly how they acquire mass (but it's probably the Majorana process).

There is a long list of things that we're still trying to figure out but that's not the central part of my point.

My point is actually more that we know the universe is constantly exploring a lot of " known as well as unknown, unknowns". That is, when it comes to a possible false vacuum, we do know that the universe is extremely violent and reaches energies extraordinary far above anything we can or ever will reach here on Earth. For example, Ice Cube detected a neutrino over $1\: \mathrm{PeV}$! If there is a false vacuum, it seems a lower energy state can't be reached through highly energetic processes.

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