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phantom power

(25,966 posts)
Sat Nov 2, 2013, 04:56 PM Nov 2013

How Quantum Mechanics Derives from a Revolutionary New Theory of Information

In the new work, Masanes and co put forward four postulates about the Universe. If we accept these, they say, quantum mechanics naturally follows. What’s more, their formulation solves an important question about reality—why the universe relies on quantum mechanics and not one of the numerous similar theories that physicists have recently discovered.

So what are these four postulates? Let’s go through them one by one.

1. The existence of an information unit.
This is the big new idea. It states that information exists, it comes in fundamental units and only in one type so there cannot be different types of information. Masanes and co call this fundamental unit a ‘general bit’ or gbit and say that any aspect of the Universe can be encoded given a sufficient number of them.

This idea has significant implications. If there is only one type of information, then everything in the universe must be possible with it. Or as Masanes and co put it: “Any physical process can be simulated with a suitably programmed general purpose simulator.”

Another way to think about this is that reality is substrate-independent. It’s always possible to reproduce one aspect of the universe perfectly using some other part.

2. No simultaneous encoding
This states that if a gbit is used to perfectly encode one classical bit, it cannot simultaneously encode any more information.

3. Continuous reversibility
This is the idea that a pure state can always be made to evolve into another pure state in a continuous, reversible way.

4. Tomographic locality
When a state is made of many components, it can be completely characterised by measured correlations between the individual component parts.

And that’s it. Masane and co go on to show that combining the mathematical formulations of these ideas leads directly to quantum mechanics. Indeed, they show that the only theory that obeys them all is quantum mechanics.

That’s significant because by relaxing some of these ideas, other types of physics emerge. For example, relaxing the condition of continuity in the second postulate leads to the classical probability theory that governs the macroscopic world.

...

In some ways this is equivalent to the position that physicists found themselves in 200 years ago when thinking about energy. They knew energy was important but were overwhelmed with the different forms it could take—chemical energy, heat energy, gravitational potential, kinetic energy and so on.

It was the realisation that all these were different manifestations of the same fundamental thing that solved this problem. That led to the law of conservation of energy and to profound new insights into the universe.

https://medium.com/the-physics-arxiv-blog/4487489dbb34
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How Quantum Mechanics Derives from a Revolutionary New Theory of Information (Original Post) phantom power Nov 2013 OP
I have to read this more carefully. longship Nov 2013 #1

longship

(40,416 posts)
1. I have to read this more carefully.
Sat Nov 2, 2013, 05:22 PM
Nov 2013

Sounds weird on first reading. This isn't the quantum I studied.

One never knows about these things, though. A caution is advisable. I will leave it to one better informed than most on the issue.

If you think you understand quantum theory, you don't understand quantum theory.

Richard P. Feynman (1918-1988), a physicist of some note.


There is plenty of room for new things about quantum theory. The big deal is separating the wheat, Quantum Field Theory, from the chaff, What the Bleep Do We Know?.

Then there's so-called String Theory which resides in the murky middle ground with no outright successes in spite of rather huge efforts by very smart people.

I have become quite skeptical about anybody claiming to have solved the interpretation problems of quantum theory.

R&K
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