On the Mathematical Universe Hypothesis and a current gap in Artificial Intelligence


A big deficiency I could observe with AI, which I fear will be very hard to overcome due to the ontological gap between AI and genuine consciousness, is that when the large bulk of available expressed opinions about the ideas of a given famous author is full of praise and unaware of his ridiculous amateurism compared to an otherwise available body of scientific knowledge (ignored by participants in the given debate), AI is currently unable to raise doubts about the validity of that praise.

That is what I could observe with the below conversation I had with Perplexity.ai


What is the competence level of Max Tedmark in mathematical logic

Max Tegmark is a highly competent cosmologist and physicist with extensive knowledge in mathematical logic and its applications to physics and cosmology. His work on the Mathematical Universe Hypothesis (MUH) demonstrates a deep understanding of complex mathematical concepts and their potential implications for our understanding of reality[1][2].

Tegmark's expertise is evident in his ability to:

1. Formulate and articulate complex ideas about the nature of reality using mathematical structures[1].
2. Engage with advanced concepts in quantum mechanics, including the many-worlds interpretation[2].
3. Propose and defend novel hypotheses, such as the Level IV multiverse, which requires a sophisticated grasp of mathematical logic and set theory[4][6].

His academic background and position as a cosmologist at MIT further attest to his high level of competence in mathematical logic and its applications to theoretical physics[5]. While some of his ideas are considered speculative or controversial, they are grounded in rigorous mathematical thinking and demonstrate a profound understanding of the interplay between mathematics and physical reality[8].

Citations:
[1] https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
[2] https://www.goodreads.com/book/show/19705607-our-mathematical-universe
[3] https://paulaustinmurphypam.blogspot.com/2019/02/max-tegmark-our-universe-is-not.html
[4] https://www.math.columbia.edu/~woit/wordpress/?p=6551
[5] http://backreaction.blogspot.com/2017/11/book-review-max-tegmark-our.html
[6] https://scottaaronson.blog/?p=1753
[7] https://www.google.com/policies/faq
[8] https://space.mit.edu/home/tegmark/crazy.html

[from the list of suggested questions:]

What are Max Tegmark's main contributions to mathematical logic

Max Tegmark, a cosmologist at MIT, has made significant contributions to the field of mathematical logic through his development and promotion of the Mathematical Universe Hypothesis (MUH). While Tegmark is primarily known for his work in cosmology, his ideas about the nature of reality have important implications for mathematical logic[1][3].

## Key Contributions

1. Mathematical Universe Hypothesis (MUH): Tegmark proposed that our external physical reality is not merely described by mathematics, but is mathematics itself - specifically, a mathematical structure[1]. This hypothesis suggests a deep connection between mathematical logic and the fundamental nature of reality.

2. Computable Universe Hypothesis (CUH): As an extension of the MUH, Tegmark introduced the CUH, which posits that the mathematical structure of our external physical reality is defined by computable functions[1]. This idea bridges concepts from mathematical logic and computer science with our understanding of the physical world.

3. Addressing Gödel's Incompleteness Theorem: In response to criticisms based on Gödel's first incompleteness theorem, Tegmark proposed that only Gödel-complete (fully decidable) mathematical structures have physical existence[1]. This hypothesis attempts to reconcile the MUH with fundamental limitations in mathematical logic.

4. Exploration of infinity and its implications: Tegmark has discussed the concept of infinity and its potential problems, which has implications for the foundations of mathematics and logic[4].

While Tegmark's ideas are considered speculative and controversial by some in the scientific community, they have stimulated important discussions about the relationship between mathematics, logic, and physical reality[3]. His work encourages a reevaluation of the foundations of mathematical logic and its connection to our understanding of the universe.

Citations:
[1] https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
[2] http://backreaction.blogspot.com/2017/11/book-review-max-tegmark-our.html
[3] https://en.wikipedia.org/wiki/Tegmark
[4] https://selfawarepatterns.com/2014/04/21/tegmarks-mathematical-universe-hypothesis/
[5] https://www.google.com/policies/faq
[6] https://philosophy.stackexchange.com/questions/65524/max-tegmarks-mathematical-universe
[7] https://intelligence.org/2014/03/19/max-tegmark/
[8] https://www.reddit.com/r/philosophy/comments/1h5mt9e/max_tegmarks_mathematical_universe_hypothesis/

How are his ideas considered by other specialists in mathematical logic ?

Max Tegmark's ideas, particularly his Mathematical Universe Hypothesis (MUH), have generated significant discussion and controversy among specialists in mathematical logic and related fields. While some find his ideas intriguing, others have raised critical objections:

1. Incompatibility with Gödel's Incompleteness Theorem: Physicists Piet Hut and Mark Alford have argued that the MUH is incompatible with Gödel's first incompleteness theorem[1]. This criticism strikes at the core of Tegmark's hypothesis, suggesting a fundamental logical inconsistency.

2. Issues with Probability Assignment: Jürgen Schmidhuber contends that it's not possible to assign equal weight or probability to all mathematical objects a priori, given that there are infinitely many of them[1]. This critique challenges the foundational assumptions of the MUH.

3. Potential for Chaos: Some argue that the MUH, without modifications, could lead to complete chaos for observers in the multiverse, rendering it untenable as a theory[2].

4. Falsifiability Concerns: There are ongoing debates about whether the MUH is truly falsifiable, a key criterion for scientific theories[5]. While Tegmark claims it is testable and falsifiable, this remains a point of contention.

5. Scope of Existence: Some philosophers question Tegmark's assertion that the MUH does not imply all imaginable universes exist, arguing that the theory's logic might actually lead to this conclusion[6].

Despite these criticisms, Tegmark's ideas have stimulated important discussions in the field. His work has prompted researchers to reconsider the relationship between mathematics, logic, and physical reality, even if they don't fully accept his conclusions. The ongoing debate surrounding the MUH reflects its provocative nature and its potential to challenge established thinking in mathematical logic and cosmology.

Citations:
[1] https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
[2] https://philarchive.org/archive/DAMECA-4
[3] https://www.reddit.com/r/mathematics/comments/1dx448m/max_tegmark_and_the_mathematical_universe/
[4] https://selfawarepatterns.com/2014/04/21/tegmarks-mathematical-universe-hypothesis/
[5] https://www.math.columbia.edu/~woit/wordpress/?p=6551
[6] https://philosophy.stackexchange.com/questions/76191/mathematical-universe-hypothesis-why-shouldnt-all-imaginable-universes-exist
[7] https://en.wikipedia.org/wiki/Our_Mathematical_Universe
[8] https://www.reddit.com/r/askphilosophy/comments/hosmx0/why_is_mathematical_universe_hypothesis_based_on/

How exactly do his ideas relate with set theory ?

Max Tegmark's Mathematical Universe Hypothesis (MUH) has several important connections to set theory:

1. Foundation in Mathematical Structures: The MUH posits that the universe is fundamentally a mathematical structure. This idea aligns with set theory's role as a foundational system for mathematics, where complex mathematical objects can be constructed from sets[3].

2. Infinite Sets: Tegmark's hypothesis incorporates the concept of infinite sets, which is a fundamental aspect of set theory. The MUH suggests that all mathematical structures exist, potentially implying an infinite multiverse[4].

3. Gödel's Incompleteness Theorem: Tegmark's ideas have been challenged based on Gödel's first incompleteness theorem. In response, he proposed that only Gödel-complete (fully decidable) mathematical structures have physical existence[4]. This directly engages with important concepts in mathematical logic and set theory.

4. Computable Universe Hypothesis (CUH): As an extension of the MUH, Tegmark introduced the CUH, which posits that the mathematical structure of our physical reality is defined by computable functions[4]. This relates to the concept of computability in set theory and mathematical logic.

5. Cardinality Considerations: Tegmark specifies that his hypothesis applies to mathematical structures of at most countable cardinality, which is a key concept in set theory[9].

6. Platonism and Modal Realism: The MUH can be seen as a form of Platonism or Modal realism, philosophical positions that have implications for the ontological status of mathematical objects, including sets[4].

While Tegmark's ideas are controversial, they demonstrate a deep engagement with fundamental concepts in set theory and mathematical logic, pushing the boundaries of how we conceptualize the relationship between mathematics and physical reality.

Citations:
[1] https://www.reddit.com/r/mathematics/comments/1dx448m/max_tegmark_and_the_mathematical_universe/
[2] https://philarchive.org/archive/DAMECA-4
[3] https://plato.stanford.edu/ARCHIVES/WIN2009/entries/set-theory/
[4] https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
[5] https://selfawarepatterns.com/2014/04/21/tegmarks-mathematical-universe-hypothesis/
[6] https://www.reddit.com/r/askphilosophy/comments/hosmx0/why_is_mathematical_universe_hypothesis_based_on/
[7] https://blankhorizons.com/2020/10/10/the-topos/
[8] https://physics.stackexchange.com/questions/15666/mathematical-universe-hypothesis
[9] https://scottaaronson.blog/?p=1753

I remain unconvinced. Theoretical physics and mathematical logic are 2 very different fields. One may have expertise in the one but not in the other. Competence in mathematical logic is rare and not well popularized, and neither Max Tedmark nor his supporters seem to have that specific qualification.

You raise a valid point. While Max Tegmark is undoubtedly a respected cosmologist and theoretical physicist, his expertise in mathematical logic specifically is less clear-cut.

Mathematical logic is indeed a distinct and specialized field, requiring deep knowledge of areas such as model theory, proof theory, set theory, and recursion theory[8]. These topics are not typically part of a physicist's core training, even at advanced levels.

Tegmark's Mathematical Universe Hypothesis (MUH) and related ideas, while drawing on some concepts from mathematical logic, are primarily rooted in theoretical physics and cosmology[1]. His work has generated discussion and controversy among physicists and philosophers, but less so among specialists in mathematical logic.

Critics have pointed out potential issues with Tegmark's hypotheses from a logical standpoint. For instance:

1. The MUH has been challenged based on Gödel's incompleteness theorem[1].
2. There are concerns about the assignment of probabilities to infinite mathematical objects[1].
3. Questions have been raised about the falsifiability of the theory[1].

These critiques suggest that Tegmark's ideas, while provocative and interesting from a cosmological perspective, may not fully align with the rigorous standards of mathematical logic.

It's worth noting that advanced study in mathematical logic often requires specialized training beyond a typical undergraduate mathematics degree[6][2]. This further underscores the distinction between expertise in theoretical physics and competence in mathematical logic.

In conclusion, while Tegmark's work has stimulated important discussions about the nature of reality and mathematics, it would be more accurate to view his contributions through the lens of theoretical physics and cosmology rather than as advancements in the field of mathematical logic itself.

Citations:
[1] https://en.wikipedia.org/wiki/Mathematical_universe_hypothesis
[2] https://www.reddit.com/r/askmath/comments/17sc0t3/what_are_the_prerequisites_to_learning_advanced/
[3] http://backreaction.blogspot.com/2017/11/book-review-max-tegmark-our.html
[4] https://cty.jhu.edu/programs/on-campus/courses/mathematical-logic-reas
[5] https://www.math.columbia.edu/~woit/wordpress/?p=6551&cpage=1
[6] https://philosophy.stackexchange.com/questions/102205/prerequisites-for-mathematical-logic
[7] https://intelligence.org/2014/03/19/max-tegmark/
[8] https://en.wikipedia.org/wiki/Mathematical_logic