The mental Universe (2005) [pdf]
henry.pha.jhu.edu
henry.pha.jhu.edu
The entirety of the universe is only accessible as the solution to a massive (or maybe not, we may discover, although that’s not likely given the state of physics at the moment) set of governing equations.
The origin of these equations is mathematics itself, i.e. a completely platonic and immaterial thing. The fact that they exist means that a single solution may spool out of them: set an initial condition, and carry forward until t=infinity. The universe is exactly the product of this. But it’s not because anything actually computes anything - it’s just a natural consequence of the existence of such equations that there is some set of solutions to them.
This also means: an infinite number of IVPs for the governing equations of “our universe,” and an infinite number of such governing equations for all the other universes.
The spring mass damper model that I can see in my textbook exists in mathematical fact, and is a universe thusly.
Why is that? Well, it arises from the purity of mathematics itself, which is actually God.
That’s my theory at least.
> the wave function is collapsed simply by your human mind seeing nothing. The Universe is entirely mental.
So what is this "mental nature of the Universe"? If the things we see at the macro scale are not made of underlying particles and waves, what are they made of?
The idea is that by clever positioning of detectors, it is possible to make a quantum observation before the detection physically occurs. That challenges the notion that wave-function collapse is a result of instruments interfering with the system.
This doesn't imply that the system "knows" anything about the conscious mind observing it. Very few physicists actually believe that consciousness affects physical mechanisms in this way. A more plausible interpretation may be that the wave-function collapse represents a belief-update process on the part of the observing agent.
This has a lot of appeal partly because wave function collapse looks very similar to the way that probabilities are updated in bayesian statistics when new information comes to light. For example, if I measure the polarisation of a photon in the vertical component and get a "yes" results (V1=y), then I have complete confidence that future measurements of the vertical will again get a "yes" result (V2=y), whereas future measurements of the horizontal component will be 50-50 between a "yes" result (H2=y) and a "no" result (H2=n).
P(V2=y | V1=y) = 1
P(V2=n | V1=y) = 0
P(H2=y | V1=y) = 0.5
P(H2=n | V1=y) = 0.5
You can sum this up as "the wave function is a way for me to keep track of probabilities, rather than an objective fact about the system".
Of course this idea has its own set of challenges. For many people the question becomes "what does the wave function represent knowledge of"? Also, a few years ago there was a thought-experiment known as the PBR theorem, which rules out some epistemic interpretations: https://en.wikipedia.org/wiki/PBR_theorem
There is a good set of slides on the PBR theorem and its implications by Jon Barrett here (he was my external viva examiner): http://www.cs.ox.ac.uk/qisw2012/slides/barrett.pdf
One class of epistemic interpretations that persists are the so-called bayesian interpretations of quantum theory: https://en.wikipedia.org/wiki/Quantum_Bayesianism .
A "strong" version of quantum bayesianism is QBism, which asserts that quantum theory is no more than an effective user manual for organising subjective beliefs about the outcomes of future interactions with the world. Chris Fuchs and Ruediger Schack are two prominent theorists advocating QBism.
Consider you never stopped dreaming when you woke up, the dream just shifted into a more concrete and physical state. But there is no physical you sleeping in some higher reality.
Mind is the rock bottom.
https://en.wikipedia.org/w/index.php?title=Mind_only
Quantum mechanics and the "observer effect" seem to be coming to similar conclusions, dragging postmodern materialists to consider the "mind" as fundamental to physics.
And what are they made of? Potential! Universal potential collapses as state in the moment of now through entropic resolve.
Measurement (as part of the collective resolve of the environment) disturbs this resolve, affecting its distribution.
The same stuff that all the stuff in your dreams are made of...
Framing it in this way ("substratum") is perhaps flawed because it assumes a layering up of sorts with an initial unfurling form null. After all, what generates the mental-like substrate? What's at the bottom of the stack? While layers may be an emergent appearance, I'm less convinced that it is the fundamental nature.
What if it is more circular, not layered? Feedback loops with co-dependent unfurling, emergence, and renewal.