When Does the Universe Compute?

KentuckyFC writes "The idea that every physical event is a computation has spread like wildfire through science. That has triggered an unprecedented interest in unconventional computing such as quantum computing, DNA computing and even the ability of a single-celled organism, called slime mold, to solve mazes. However, that may need to change now that physicists have worked out a formal way of distinguishing between systems that compute and those that don't. One key is the ability to encode and decode information. 'Without the encode and decode steps, there is no computation; there is simply a physical system undergoing evolution,' they say. That means computers must be engineered systems based on well understood laws of physics that can be used to predict the outcome of an abstract evolution. So slime mold fails the test while most forms of quantum computation pass."

Re:I don't think encoding/decoding are fundamental

[Hatta]

We only don't see the encoding and decoding steps because we are inside the system that is doing the computation. If the universe were a simulation, those inside the simulation would see a ball trace a parabola with no encoding or decoding steps. Those who designed the simulation would be well aware of those steps.

Re:Definitions

[gstoddart]

Sounds like they are arbitrarily defining computing as a simulation of the universe, therefore the actual universe cannot compute.

Or that they're saying the universe doesn't need to do calculations to determine where a falling object is going -- it just falls according to the laws of physics and doesn't need to be calculated.

I think this unnecessarily limiting people's imagination.

Does 'imagination' in this context actually tell us anything? We know that we need to do calculations for this stuff, but how does the assertion that the universe isn't doing the calculations limit our imagination? Stuff happens according to physical laws, the behavior is inherent to reality. Nobody has to do the math, it just happens.

Besides, from the inside of a simulation its all real to you.

Very meta, and equally meaningless. Yes, if we were in a simulation, we'd likely never know.

But given that we have no evidence to suggest we are, any assumptions around the notion that we are (or may be) are pretty much useless to us unless we can figure out the gaps in the simulation.

To me the suggestion we're living in a simulation serves no other purpose that throwing out something wacky to stump people at parties, but otherwise doesn't seem to have any application to understanding our universe.

Re:I don't think encoding/decoding are fundamental

[HybridST]

When thermodynamics is wrong, you've missed something.

Re:I don't think encoding/decoding are fundamental

[ultranova]

The laws of thermodynamics are obviously wrong. Wrong in the same way that Newtonian physics is wrong. Meaning that it is close enough for anything I will ever get my hands on, but that it clearly does not explain everything that is happening, and it is clearly violated at some point.

Please give an example of such violation? Because I'm afraid I can't see this obvious flaw you posit.

Comment removed

[account_deleted]

Comment removed based on user account deletion