Scott Aaronson has gotten a couple of students to help him realize Worldview Manager, which asks you to indicate a level of agreement or disagreement with various statements on a topic, and then detects "tension", i.e. something akin to inconsistency, between your responses. No significant tension was found in my views on quantum computing, but on quantum mechanics (mostly fairly foundational questions), here's what the thing came up with:
"Tension detected!
You indicated
- Disagreement with the statement "There is a single wave function for the universe, which has been evolving unitarily since the big bang."
- Agreement with the statement "There is no faster-than-light communication."
It would seem that this is logically inconsistent. Please consider modifying your responses. If you do not want to resolve this tension now, you can defer it until later.
If you are confused as to why this represents a logical inconsistency, you can read our explanation."
I did, although you could more properly say I was being too lazy to even be confused... As a not entirely irrelevant side note, I only indicated 20% agreement (via a slider scale with no numbers attached, though) with the "no faster-than-light communication" statement (and 80% disagreement with the other).
"Here is a brief explanation as to why your answer selection represents a logical inconsistency.
Let
* A be the statement:
There is no faster-than-light communication.
* B be the statement:
There is a single wave function for the universe, which has been evolving unitarily since the big bang.
* C be the statement:
The collapse of the wave function (i.e., measurement) is a real physical process, not explainable in terms of unitary evolution.
Then A implies B as follows:
* One of C or B because
If there's no collapse process, then presumably one could in principle write down a wavefunction for the entire universe.
* C implies not A because
If collapse is a real physical process, then it requires a form of faster-than-lightsignalling when applied to entangled states."
I guess I don't yet agree with the "presumably" above, and so not with "One of C or B". I don't believe "there's no collapse process", just that it's not a "physical process". On the view I lean toward, the wavefunction is probably not a "real physical entity", it is a tool we are using to help understand and predict the behavior of systems, so the fact that its collapse isn't a physical process doesn't imply that there's no collapse.
Time for some coffee. Am I missing something?
Just for the record, my full answers so far:
Quantum Computing | ||
The Threshold Theorem provides a convincing demonstration that, because of the linearity of quantum mechanics, it is possible in principle to correct errors in a quantum computer faster than they occur. | 80% Agreement | |
It is possible to simulate any quantum system on a classical computer in polynomial time (i.e., exponentially faaster than the "naïve" method of writing down the entire wavefunction). | 80% Disagreement | |
Quantum mechanics as described in standard physics textbooks is an accurate framework for all of physics. | 40% Disagreement | |
If quantum mechanics as described in standard physics textbooks is true, then it is possible in principle to build a scalable quantum computer. | 90% Agreement | |
Any quantum computer will inevitably be subject to noise and decoherence that will prevent it from exponentially outperforming a classical computer. | 80% Disagreement | |
A fast classical algorithm for factoring integers will eventually be discovered. | 20% Disagreement | |
The Extended Church-Turing Thesis is false: that is, it is possible in principle to build computers that efficiently solve problems outside the complexity class BPP. | 30% Agreement | |
A quantum computer is essentially an analog computer, and will fail to scale for the same reasons classical analog computers failed to scale. | 80% Disagreement | |
Quantum Mechanics | ||
There is a single wave function for the universe, which has been evolving unitarily since the big bang. | 80% Disagreement | |
Quantum mechanics is an experimentally successful description of the behavior of microscopic systems. | 90% Agreement | |
For a physical theory to make sense, it must have some notion of "the past" besides just memories and records in the present. | Completely neutral | |
There is no faster-than-light communication. | 20% Agreement | |
Mixed states, as the most general representation of an agent's knowledge of a quantum system, are more fundamental than pure states. | Completely neutral | |
Quantum mechanics is about our knowledge and information, not directly about ontology (i.e., what really exists). | 30% Agreement | |
When measuring a quantum state, we have the freedom to choose the measurement basis (for instance, whether we want to measure the position or momentum). | 30% Agreement | |
The outcome of every quantum measurement is "preordained" from the beginning of the universe. | 50% Disagreement | |
Quantum mechanics shows that consciousness or observation must play some fundamental role in the laws of physics. | 20% |