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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."
"I'll get it," a wife said to her husband as the phone rang.
On the line a pervert, breathing heavily, said, "I bet you have a tight asshole with no hair."
"Yes," she responded. "He's sitting next to me watching TV."
Why can we not think of the information as being embodied in "some aspect or other of" the matter and energy undergoing evolution. It is only some observer that needs to see the information as having been encoded or decoded.
Metrics of computations, or measurements of information flows, may be a productive way of describing (and predicting) complex physical evolutions, regardless of whether the physical system itself is identifiably encoding and decoding information explicitly. You just have to establish your own observer convention for how you think the information is represented in the matter and energy under discussion, or you can even just think about "the maximum amount of information" that could be contained in that matter/energy/spacetime region, and the maximum possible amount of information flow there.
Where are we going and why are we in a handbasket?
The type of computation discussed in this article is not the type of computation used in the phrase "every physical event is a computation". These physicists are trying to discern computation from physical processes by discerning whether the process can encode information in its initial conditions, and other information can be extracted from its results. This is good when trying to determine which processes lend themselves to building computers, but it does not address the question of whether the universe is a computer, and whether the laws of physics are merely closed form equations describing some of its operational semantics.
Higher Logics: where programming meets science.
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.
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.
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.
Lost at C:>. Found at C.
Psst! It's an Analog Computer, they're way faster and more flexible than digital ones, but don't tell anyone or I'll be modded down into oblivion.
A feeling of having made the same mistake before: Deja Foobar
It's much more complicated than that. Myxogastria can be onecelled and mononuclear, and they can be multicelled and multinuclear, and they can even be onecelled and multinuclear - all within the same organism. A single plasmodium cell can contain up to 10 mio nuclei and span several square meters. Thus it would be better to call the plasmodium acellular, as it has no inner cell structure.
For example, the processes that slime mould uses to solve a maze are largely unknown. For this reason it is not computation.
Don't we usually declare characteristics of things based on what we know about them, rather than on the basis of not knowing about them?
Seems like a strange kind of subjective solipsism--"what is, is dependent upon on what I currently know is".
~ Whence do you come, slayer of men, or where are you going, conqueror of space?
See subject.
Fuck systemd. Fuck Redhat. Fuck Soylent, too. Wait, scratch the last one.
I RTFAed. Their theory is essentially that computation can only be said to have occurred if you know the physical nature / laws that allowed the computation to occur.
Which is BS. There are plenty of people who can add 2 numbers on a calculator without knowing anything about electrons, bits, electronics etc. You can extend that until the number of people who understand specific physical laws underlying a computation is zero.
Since when is human knowledge the test for whether any computation is happening? All they are saying is "If we don't understand it, we will not call it computation." Way to go with the semantic circus.
Entia non sunt multiplicanda praeter necessitatem.
Point particles come from the interaction of various waves which carry force. Points don't even take up space. The Universe is one giant 2D wave, and all 3D space is holographic illusion.
Look, seriously, Doom was DECADES ago at this point. The rest of the world's moved on, you really need to stop living in the past and base your universal theories on something OTHER than an engine Carmack made back in the DOS era.
doesn't seem to have any application to understanding our universe.
If we are a simulation, we may be able to discern exactly what we're simulating, and why. Theology aside, even discovering that our universe functions like a simulation may allow us to seek out and utilize aspects of the simulation that are useful to us.
Consider, for example, if we could simply access an information store outside our universe from anywhere within it. Even a single bit being accessible would offer the ability to have near-instant communications with other planets, or perhaps even other stars. If we could push matter out of or into the universe, we'd have an effective teleportation mechanism.
Science is all about figuring out the rules of our universe. Being inside a simulation means there are other, possibly different, rules outside, so breaking out means we have new capabilities that are impossible within our universe.
You do not have a moral or legal right to do absolutely anything you want.
I.e., the idea of the entire universe as constituting some sort of universal computational substrate.
The idea is probably wrong, mainly because every "my conception of the fundamental nature of the universe based on just discovered science" is wrong, due to the time-bound nature of our perceptions.
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/
Let me guess - those dancing angles are doing the tan-go?
Physicists, please leave this to computer people. Interpretation is just a transformation, and is no magic door to computational efficiency.
If a slime mold could, via interpretation, solve some NP-Hard problem, that would be an astounding result with major implications for the computational ability of the universe.
This is independent of the interpretation. It is the equivalency of reducing a problem to another, of which physicists are indeed well aware.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.
"A physical system undergoing evaluation" is pretty much what a computation on a physical device looks like. Seems some physicist(s) with their usual search for meaning when the midlife-crisis strikes but little idea of Computer Science drummed something up that does not make a lot of sense. The issue is of course that the encoding and decoding steps (properly called abstraction and application) are only necessary when you have a computing device using a different primary mechanism that the device the calculation apply to. For example, when doing analog computations in a radar system, you do not change the mechanism, the signal already is electrical and analog. Hence when doing, day, computations for gravity, there would well be an invisible tiny "gravitational computer" in any particle affected by gravitation that uses the available input directly.
Of course, there is always the (likely) possibility that this whole universe is only a simulation, and all perception of it we have is a cleverly crafted illusion. In that case the abstraction step is not necessary either, except possible in the bi-directional channel that delivers the illusion to each of us. (Solipsists win the most here: Only one bi-directional channel needed for the whole universe ;-)
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
Your "proof" only illustrates one particular case, which does not necessarily apply to the question at hand.
It is indeed like Plato's cave, and the same lesson applies: Occam's razor is not always correct. Sometimes there are really weird truths, and with enough experiments, they can be discerned. Perhaps that MP3 player takes a little longer between songs while it tries to randomize the list. With a long enough recording of the playback at a high enough precision, the slight delay can be noticed, and that analyzing nerd can announce the mode with certainty.
The fundamental basis of all science is that we are wrong. Aristotle was wrong, Newton was wrong, Einstein was wrong, Hawking was wrong, and every scientist today is probably wrong about something. The scientific method allows us to become right. Each successive scientist makes more and better observations than his predecessors, notices what observations don't match the old law's predictions, theorizes new hypotheses to fit existing data, then experiments to test the hypothesis. Eventually, a new theory replaces the old one for situations where the new (and probably more complex) theory is necessary.
In your thought experiment, you said "relying on your ears only". This is as much a mistake as saying that time is measured on a wristwatch only, which is, of course, far too imprecise to test the effects of relativity at attainable speeds. As technology improves, so does our ability to measure and observe, giving us more data on which to base our hypotheses, such as the few-cycle timing differences in the playback. There may be just such a slight defect in our universe, that would open up a whole new field of study in trans-universal physics. There also may not be. We haven't observed such a thing yet, but we should not be so arrogant as to assume that our current knowledge is absolutely all-encompassing.
You do not have a moral or legal right to do absolutely anything you want.