How to Predict a Scientific Revolution

Sarah Jones Nelson

Adviser to the Vatican

Pontifical Lateran University

IRAFS: International Research Area on Foundations of the Sciences

International Symposium on Science and Theology: The Challenge of Quantum Gravity in

Modern Cosmology

October 20-21, 2022

For historical perspective on this historic occasion, let us turn to the twin revolutions of science

and theology — of facts and values — simmering in early modern Europe.

On June 4, 1539 in Wittenberg, Germany at his dinner table with colleagues and students, Martin

Luther called Galileo that fellow who wants to prove the earth moves and turns all astronomy

upside down. Luther had already turned religion upside down. In 1517 he catalyzed the

Protestant Reformation by proclaiming 95 points of public debate against indulgences or cash

donations in exchange for salvation during a papal campaign to fund needed repairs to St Peter’s

Basilica.

Pope Leo X excommunicated Luther, a professor of biblical interpretation. On the authority of

scripture, Luther later agreed with Galileo’s inquisitors that the sun revolves around the earth.

Their official proof text, Joshua 10:12-14, narrates Israel’s victory over the Amorites; Joshua

commands a rotating sun to stand still at Gibeon, and the moon at Aijalon. Because of his

dissenting proof of the laws of motion, Galileo spent the rest of his life from 1633 onward a

heretic under house arrest at his villa near Florence.

This first crucible of political and biblical theology turned the ground of certainty spinning

upside down in all directions. Science and theology would never be the same: a foretaste of the

way testable proof — and strong emotions — can cause revolutions.

Fast forward September 18, 2019, to my seminar table talk on the physical foundations of theory,

Department of Physics, Princeton University. A small group took on quantum gravity. Gerard ‘t

Hooft, one of our esteemed speakers today, spoke of quantum mechanics as a tool to solve

problems. Turning quantum mechanics upside down, he said, is a solution.

String theorist Edward Witten responded: The fact that quantum mechanics can be used to solve

non-quantum mechanical problems suggests that quantum mechanics is more powerful than

classical mechanics.

Christopher Tully: With all the great achievements of quantum mechanics we are not certain that

our discussion of origins is on solid theoretical ground. What if you have an infinite number in

initial conditions? Does that mean your initial state and properties in only one state make a

superposition? Initial conditions are special. Why hasn’t gravitational instability taken over?

Why hasn’t everything collapsed into a black hole?

James Peebles: We are in one giant wavefunction from the start. And we don’t know what’s

beneath quantum mechanics. We do not have the state under quantum mechanics. What is the

deeper underlying theory? How deep do you go? How do you know when to stop?

Intense discussion: Are observables in the early universe fixed initial conditions? Are all sets of

initial conditions consistent with what we observe today? Suppose you do an EPR experiment to

test the hypothesis. You measure two CMB photons at the same time. Do they have some level of

entanglement consistent with initial conditions?

Wavefunction initial conditions are hidden, and it’s unclear that the numbers are well defined.

Questions: Are the laws of nature definable? If you deny definability do you deny the existence

of pure, precise laws of nature? Are we using the right concepts? What’s up with free will, initial

conditions, and nonlocality? Do ontological states exist with zero uncertainty at an entangled

initial state wired for infinite expansion?

Being in one giant wavefunction from the start means that we exist in a wavefunction that caused

the quantum state of physical reality. Thus the wavefunction is foundational to quantum

mechanics as the sine qua non of any progress in observational cosmology.

Roger Penrose, one of our online seminar participants, published with Stephen Hawking a

mathematical description of the gravitational collapse which produces black holes. He now

believes that the Copenhagen interpretation of quantum mechanics is subjective and therefore

uncertain because of observer dependence on the collapse or state reduction of the wavefunction.

The wavefunction quantum state up to proportionality, he says, should be given the objective

ontological status of a physical object.

Here we encounter the challenge of quantum gravity, with the help of the right tools, to turn

quantum mechanics upside down. More on this in a few minutes.

What if the wavefunction is not simply a mathematical formulation of all possible or probable

observable states determined by observation and measurement? Perhaps gravity or dark matter

induces the state reduction of the wavefunction. Catalina Curceanu, also an online seminar

participant, runs a laboratory in Gran Sasso. She is constructing a wavefunction model relating to

physical reality and, importantly, to nonlocality. Her experiments will advance our knowledge of

entanglement and quantum gravity.

Experimental work of this nature can give us a better understanding of the wavefunction at the

initial state. It can inform models of quantum gravity. It will help modify the standard model to

give us more precise laws of nature toward a consistent ontology of quantum mechanics and its

underlying nature, not just new mathematics where the axioms of arithmetic are unprovable.

The new physics must solve a deeply problematic conflict of interpretations for one universe

governed by two sets of contradictory laws. That conflict explains why so many in the theoretical

community believe that our standard concepts of spacetime will have to change. This means

revolution with profound consequences for cosmology.

Why cosmology? The standard cosmological model requires testable initial conditions to predict

certain outcomes. At the initial state, however, no tools or instruments yet exist to test or probe

the initial conditions of spacetime emerging, say, from an entangled quantum state to the

classical universe described by Einstein’s gravity.

This is why any foundational claim to a consistent ontology of quantum and classical mechanics

at the initial state is uncertain. Even if we can infer rightly that the Big Bang was a singularity, it

is still conjectural. We have no testable evidence for the initial causal mechanisms of structure

formation and expansion from the first singularity. Why? Because the initial state is

unintelligible without predictive theory of confirmed, observable initial conditions. Without the

evidence of observables we have metaphysics — holograms, strings — not ontology.

The good news is instrumentation on the order of Galileo’s 1609 retooled Dutch telescope. Now,

from the mountaintops of Chile, Princeton University’s CMB telescope team has confirmed

testable observables from the cosmic microwave background radiation: fossil evidence of the

early universe 380,000 years after the initial state. What happened before that state, however, is

vigorously contested.

Contested also is the nature of quantum mechanics at the primordial regime, before CMB

evidence, at all scales such as the Planck scale of primordial pure quantum black holes. Here

again we encounter the challenge of quantum gravity. How can primordial black holes at the start

of structures emerge with interior properties of such laws as gravity which will necessarily break

down? Published images of black holes show that the blackhole boundary confirms general

relativity. What else can we infer about the interior of this unitary physical object? Did quantum

mechanics apply at initial conditions of pure-state quantum black holes at the Planck scale?

If the wavefunction describes the quantum state of everything that exists, it describes the

quantum state of black holes, now given objective status by the Event Horizon Telescope (EHT)

directed at Harvard University by our speaker Shep Doeleman, collaborating with Peter Galison,

Director of the Harvard Black Hole Initiative. I predict that the next-generation EHT (ngEHT)

will generate data at the blackhole event horizon from which to credibly infer or observe the

properties of physical dynamics inside a black hole. The result? A revolution. The laws of nature

will never be the same. An intuition: the ngEHT gives the wavefunction objective status.

Observable effects of the wavefunction show it to be a physical object in a singularity from

which to infer the mechanisms of the initial singularity.

We live in a world of paradox. The probability of an entangled initial singularity emerging from

a quantum state expanding to a classical state suggests to me initial conditions in which an

objectively real wavefunction physically acts upon each state at the effect of the EPR paradox. If

measurements disentangle quantum systems such as the wavefunction, fundamental physical

theory will have to change.

Will wavefunction initial conditions always be hidden between the lines of the Book of Nature?

Will revolutionary instrumentation rewrite the chapter of hidden conditions? Quantum theory

makes epistemic claims on the origins of the universe and our consciousness of it. Are our lives

fundamentally determined by initial conditions? Are we as creative agents predestined by the

conditions of our birth, our histories and our cultures? Is free will consistent with what’s beneath

quantum mechanics and our perception of physical reality? Open questions such as these will

shape the future of philosophical and theological discourse on origins, causation and

consciousness.

To conclude I raise the question of social construction in theoretical and experimental science. I

have introduced to you an inquiring group of physicists devoted to resolving conflicts in the

community by investing in cooperation and collaboration. But social history shows how

influential groups with a fixed agenda can force conformity to wrongthink.

Original thinkers from Aristotle to Spinoza to Turing have suffered deeply for differing from

fashionable groupthink. In contemporary culture groups can easily ignore or abuse unfashionable

ideas ahead of the curve. Think of Virginia Woolf, John Bell, Hugh Everett, uncountable

off-the-charts students too concerned about securing jobs to challenge groupthink as wrong as

Luther was to prooftext the Book of Joshua against confirmed laws of planetary motion.

We stand at the precipice of a revolution in contemporary physics because of highly organized

collaborations and exquisite new instrumentation. Let us listen to all voices emerging from their

courageous work of turning physics and philosophy upside down in all directions.