I What exactly is Weizsäcker's ur-alternatives theory?

[Suekdccia]

What is exactly Weizsäcker's ur-alternatives theory? How is it related to digital physics theories? Is it related to pancomputationalism? Does it defend that a universe can be described as being fundamentally made of qubits? Would this mean that that universe would be fundamentally made by information? Would this mean that, in this theory, a universe could be itself like a quantum computer?

https://en.wikipedia.org/wiki/Carl_Friedrich_von_Weizsäcker

https://en.wikipedia.org/wiki/Digital_physics

 

[A. Neumaier]

Would this mean that that universe would be fundamentally made by information?

Yes, this was his basic philosophical idea. But it is not a viable theory.

You can indirectly infer this from the fact that it appeared only in three philosophically oriented books [25-27] in the Wikipedia article, and nobody else worked on it.

He builds up infinite-dimensional Hilbert spaces from 2-dimensional ones (qubits), but fails to derive or explain the Lie algebra representations needed to equip the latter with the right physical structure.

 

[Suekdccia]

but fails to derive or explain the Lie algebra representations needed to equip the latter with the right physical structure.

What does that mean? Is it inconsistent then?

What about Wheeler's "it from bit" theory?

https://en.wikipedia.org/wiki/Digital_physics

 

[Suekdccia]

Is it inconsistent then?

(Mathematically inconsistent)

 

[Suekdccia]

Yes, this was his basic philosophical idea. But it is not a viable theory.

And if universe would be made of information, would that mean that the universe would be some kind of computer quantum itself like pancomputationalism says?

 

[JMJV]

What is exactly Weizsäcker's ur-alternatives theory? How is it related to digital physics theories? Is it related to pancomputationalism? Does it defend that a universe can be described as being fundamentally made of qubits? Would this mean that that universe would be fundamentally made by information? Would this mean that, in this theory, a universe could be itself like a quantum computer?

https://en.wikipedia.org/wiki/Carl_Friedrich_von_Weizsäcker

https://en.wikipedia.org/wiki/Digital_physics

Its the first and more developed take on the role of information in physics and QM. Instead of making a sloppy use of words to sound novel (like many do sadly, for example with "information"), Von Weizsacker really analyzed the meaning of the involved concepts. He arrived at results like the approximate numbers of Urs (qubits) in the Universe and in a simple particle, these numbers are appearing independently now in the research of modern theorists, 60 years later, people working on entropy, cosmology, the holographic principle, etc (Seth Lloyd as an example).

I won't judge a theory based on the popularity, trends govern all human affairs, physics included. He was talking about qubits decades before all the supposedly avant-garde researchers of today.

Instead of postulating that space has 23 or whatever dimensions he searched for an explanation of the 3 dimensionality of our empirical experience. Many naively accuse people like him of philosophizing but what he was really doing was making clear the nonsensical use of words and what is and what is not physics, the common trends of today (multiverse, strings, etc) are a clear example of the "mathematical metaphysics" that he was against.

Yes, his program isn't complete and work must be done, but that's the meaning of a "program". The same can be said of a lot of modern research groups. I reccomennd the latest papers of Thomas Görnitz who is working on Ur theory.

 

[A. Neumaier]

I reccomennd the latest papers of Thomas Görnitz who is working on Ur theory.

If you recommend something you'd give a reference for it.

 

[JMJV]

Oh, sorry. : T Görnitz and U Schomäcker 2012 J. Phys.: Conf. Ser.380 01202 https://iopscience.iop.org/article/10.1088/1742-6596/380/1/012025
But is far easier in google.