Bayesian Confirmation Theory is Not Science

Yesterday Edge published the results of their annual question: What do you consider the most interesting recent scientific news? What makes it important?

The Large Hadron Collider run was mentioned several times with different interpretations, depending on how you define “science”.


What is the Large Hadron Collider Doing?

Looking for superparticles.

General relativity and quantum mechanics are currently incompatible theories. Relativity accounts for gravity in the realms of planetary orbits and galaxies and an expanding universe. Big stuff. Quantum mechanics uses electromagnetism and strong and weak nuclear forces to describe the interactions between subatomic particles. Tiny stuff.

The theories don’t scale. If E=mc2, then the amount of energy from particle interactions results in so much mass that the universe should have imploded into a black hole by now [1].

A supersymmetric model unifies the theories: Every existing elementary particle has a corresponding superparticle with opposite spin. Superpartners. In theory, at high energy, colliding particles turn into the masses of their superpartners and this emits a Higgs boson.

The Higgs boson was discovered in 2012. The next step is to find a superparticle.

What was the Scientific News?

The Large Hadron Collider has thus far found zer0 superparticles. But this year, a new run began that allows even higher-energy collisions.

I have not failed. I’ve just found 10,000 ways that won’t work. –Thomas Edison

For string theorists, this is great – We have ruled out the weaker section of the energy scale and can narrow our search! The probability of finding a superparticle on this next run has increased.

Or maybe superparticles don’t exist?

How to Reach a Scientific Conclusion

We used to rely on falsifiability. Scientific theory: All swans are white (proven false by observing a black swan).

But falsifiability doesn’t work for modern physics. For example, no one has ever observed an atom. Instead, scientists apply Bayesian confirmation theory, which assigns a confidence level to the credibility of a hypothesis.

So we have atomic theory, which is approximately 100% confirmed; and then we have string theory, which is trace-amounts confirmed.

Is modern physics is even really science [2]? Science asks the questions that are answerable; philosophy asks the questions that are not. By treating unanswerable questions as answerable, we find ourselves chasing hints of particles that might lend an extra 0.00001% confidence.

And who cares about that? Who cares if we are 0.00001% sure that every existing particle has a corresponding superparticle? If that was the frontier of string theory, string theory would be boring. Modern physics is interesting not because of its data, but because it gives us a better way of understanding reality than classical mechanics. It tells us that space-time is curved, that things behave differently at a quantum scale, that we can think of point-like particles as one-dimensional strings. And the goal isn’t to find affirmative evidence beyond some arbitrary threshold, but to continuously formulate the most reliable way of thinking at the present level of knowledge.

And that’s exactly what the ancient philosophers were trying to do.

See Also:
1. Relativity versus quantum mechanics: the battle for the universe –guardian
2. A Fight for the Soul of Science –Quanta
3. There is a 94% likelihood that the multiverse exists.
J. Polchinski. Why Trust a Theory? Reconsidering Scientific Methodology in Light of Modern Physics, Munich, Dec. 7-9, 2015.

Leave a Reply