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### #121 unreality

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Posted 22 December 2010 - 12:00 AM

Thinking of the latest in physics with all the quantum stuff and string theory that I don't understand, it's also a possibility that our universe that appears simple is in fact much more complex, but has some sort of pattern or whatever to the laws which allows us to observe something that appears simpler.

This is more or less my viewpoint. We only approximate 'true physics' with our equations, which could be much simplified versions of the real thing, however accurate enough to a certain degree to be useful for us. An example would be using 1 + x + x^2 / 2 + x^3 / 6 to approximate e^x. It ignores an infinity of terms of the Taylor series but still is a very close approximation as long as x is inside a certain range.

We've seen other examples of this in physics throughout the centuries. Newton's simple laws of motion & gravity, for example, work for the kinds of numbers of speeds, distances, and times that we see in our everyday human lives on Earth, although are just approximations to the more complex "relativistic" equations.

It could be that we are forever simplifying true reality.
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### #122 Use the Force

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Posted 22 December 2010 - 06:57 AM

This is more or less my viewpoint. We only approximate 'true physics' with our equations, which could be much simplified versions of the real thing, however accurate enough to a certain degree to be useful for us. An example would be using 1 + x + x^2 / 2 + x^3 / 6 to approximate e^x. It ignores an infinity of terms of the Taylor series but still is a very close approximation as long as x is inside a certain range.

We've seen other examples of this in physics throughout the centuries. Newton's simple laws of motion & gravity, for example, work for the kinds of numbers of speeds, distances, and times that we see in our everyday human lives on Earth, although are just approximations to the more complex "relativistic" equations.

It could be that we are forever simplifying true reality.

Only someone who just learned Taylor series would use it as an example in such a circumstance Newton's laws are a much better example. But, yeah, this could definitely be true. It's not like there's a hidden set of physical laws that we are expecting to uncover. Rather, we're just trying to create equations/theories/etc that do the best job possible of describing what happens in our universe. Comparing physics to economics could be a good example of this. There are no inherent laws of economics that are built into the universe or our genes, but economists nevertheless create theories and equations to try to better understand and predict what we do economically. And also comparing physics and our universe to economics, in economics what we are actually doing is much much more complex than what the equations are that economists make to try to predict what we do in the market. So I agree with you, that our physics, like our economics, is likely just approximating what the true laws of physics make happen in our universe.

On a similar note, I wouldn't be surprised if we never found a grand unifying theory in physics like many physicists hope to find. One may simply not exist and it may indeed be true that the universe is much much more complex than it appears in the eyes of our current physics equations. It may also be that the structure of our universe is not in such a way that the simplified version we perceive of it isn't a perfect simplification... i.e. things behaving differently on small scale and large scale cannot be unified into one simple theory of everything due to the fact that they are just simple shadow approximation equations of our actual complex universe. Is what I'm saying clear? If not, how better could I communicate what it is that I'm trying to say ?
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### #123 unreality

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Posted 22 December 2010 - 07:27 AM

Only someone who just learned Taylor series would use it as an example in such a circumstance

Sorry, learned em a year or two ago. It was just the first thing that came to my head.

And also comparing physics and our universe to economics, in economics what we are actually doing is much much more complex than what the equations are that economists make to try to predict what we do in the market. So I agree with you, that our physics, like our economics, is likely just approximating what the true laws of physics make happen in our universe.

The difference is that the discrete behavior of economics means that, with enough data and computing power, we could entirely encapsulate economics. You might then say that you could extend that to physics to, with "enough data and computing power", but because of Heisenberg & whatnot and the continuum vs discrete (we don't know yet but either way), that that's not possible for physics. So there's the fundamental difference

On a similar note, I wouldn't be surprised if we never found a grand unifying theory in physics like many physicists hope to find. One may simply not exist and it may indeed be true that the universe is much much more complex than it appears in the eyes of our current physics equations. It may also be that the structure of our universe is not in such a way that the simplified version we perceive of it isn't a perfect simplification... i.e. things behaving differently on small scale and large scale cannot be unified into one simple theory of everything due to the fact that they are just simple shadow approximation equations of our actual complex universe. Is what I'm saying clear? If not, how better could I communicate what it is that I'm trying to say ?

I understand you and agree. Although if we broaden both our estimation for "large things" and "small things" enough our simplifications might find some crossover room and we could come up with a unifying theory. That doesn't mean it's right, it's still just an infinitesimal approximation to reality, but unified in one instead of separate globes. I see no reason why we can't get slightly more complex to encompass the aspect of reality we know about (our "really small" (quantum) and "really big" (galaxies) might be NOTHING compared to the true scale/scope of the universe but nevertheless we'd think we'd unified it).
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### #124 Use the Force

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Posted 22 December 2010 - 08:35 AM

Sorry, learned em a year or two ago. It was just the first thing that came to my head.

I have to say that despite the fact that I only learned Taylor series this year and despite knowing that I'm roughly a grade older than you, I strongly suspected when writing, "Only someone who just learned Taylor series would use it as an example in such a circumstance" that you had learned it a while ago and that it was just a random thought popping into your head.

The difference is that the discrete behavior of economics means that, with enough data and computing power, we could entirely encapsulate economics. You might then say that you could extend that to physics to, with "enough data and computing power", but because of Heisenberg & whatnot and the continuum vs discrete (we don't know yet but either way), that that's not possible for physics. So there's the fundamental difference

How would enough data and computing power allow us to totally encapsulate economics? The economists still wouldn't know for sure what type of car I was going to buy, etc. Sure, the economics could be a lot better, but no matter how much computing power you had it still wouldn't be perfect.

Even if the universe was deterministic, we wouldn't be able to compute the future from inside it. I think the same is true of economics. You can't perfectly predict what I'm going to buy either. So the fundamental difference you're pointing at is fuzzy; I don't see it.

I understand you and agree. Although if we broaden both our estimation for "large things" and "small things" enough our simplifications might find some crossover room and we could come up with a unifying theory. That doesn't mean it's right, it's still just an infinitesimal approximation to reality, but unified in one instead of separate globes. I see no reason why we can't get slightly more complex to encompass the aspect of reality we know about (our "really small" (quantum) and "really big" (galaxies) might be NOTHING compared to the true scale/scope of the universe but nevertheless we'd think we'd unified it).

I agree; that's definitely a possibility also.
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### #125 unreality

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Posted 22 December 2010 - 05:00 PM

How would enough data and computing power allow us to totally encapsulate economics? The economists still wouldn't know for sure what type of car I was going to buy, etc. Sure, the economics could be a lot better, but no matter how much computing power you had it still wouldn't be perfect.

Even if the universe was deterministic, we wouldn't be able to compute the future from inside it. I think the same is true of economics. You can't perfectly predict what I'm going to buy either. So the fundamental difference you're pointing at is fuzzy; I don't see it.

I guess I mean that with economics, we could model every piece of money in the universe, objects, where it is, has been, whatever. On second thought it wouldn't be very easy but that's why I said with enough "data and computing power". But then we wouldn't be able to predict the future with even that, of course (due to irrational human decision making), just model the present. We can't even model the present for physics, it's just fundamentally impossible. I guess there's not really that much of a distinction, especially if you isomorphically map them one-to-one (or at least good enough to preserve physic's uncertainty) by introducing the ability to purchase the naming rights to 'x' atom or 'y' galaxy.

So yeah you're right, it's very fuzzy. Forget the economics thing hahaha
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### #126 dawh

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Posted 22 December 2010 - 05:12 PM

How would enough data and computing power allow us to totally encapsulate economics? The economists still wouldn't know for sure what type of car I was going to buy, etc. Sure, the economics could be a lot better, but no matter how much computing power you had it still wouldn't be perfect.

Even if the universe was deterministic, we wouldn't be able to compute the future from inside it. I think the same is true of economics. You can't perfectly predict what I'm going to buy either. So the fundamental difference you're pointing at is fuzzy; I don't see it.

But if the world is deterministic, then that means that we could predict the future, given all the relevant prior facts. We could build a model of the Universe and watch it play out, if we had all the data points to start it. I think that that is in part what unreality is saying. It is possible to build mathematical models of human systems. The trouble is that the structure of human systems is subtle and often overlooked.

An economist couldn't know with 100% confidence what kind of car you might buy, but knowing enough information about you and your life, they might be able to create a prediction with a high probability of being correct. If every car your family has ever owned has been a Ford, chances are, you will buy a Ford. Knowing your income and age, they can predict what kind of Ford might be within your price range and interest. "He's young and on a tight budget. He'll probably be interested in a Ford Focus because of the fuel economy." There are entire careers built around predicting what people are going to buy. That's the business of Venture Capitalism, in a way. They want to invest their money in the next "Big Thing" that will sweep the world in a fad (or, they hope, much more).

So I agree with unreality. Given enough data points and enough computing power, I think it would be possible to predict what you or anyone else might decide to do in a given situation. Whether that is feasible to accomplish at this point in time is another matter. Of course with Google et al. data-mining every search you make and every thing you purchase online or with credit, it becomes easier to track your interests and attempt to engage your attention to products specifically catered to your buying/searching history.

I see unreality is giving up on his own argument...but it seems to me that if a system is deterministic, then it must be possible to build a model of it, given the relevant data. Can anyone think of a system that while deterministic, couldn't be modeled?
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### #127 unreality

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Posted 22 December 2010 - 05:43 PM

Yes - any deterministic system that keeps itself "blackboxed" in a way. I'm sure my understanding of Heisenberg's uncertainty principle is very very very lacking - and I really should read up on it a lot more because I seem to mention it a lot haha - but even if physics is deterministic, the "algorithm" so to speak that computes the next time-step of the universe from the previous one is hidden to observers. Or maybe not the algorithm (the laws of physics?) but rather the data itself (position/momentum of particles a la heisenberg). So even if the algorithm is known (or for that matter, really simple) we can't compute if we lack the data.

But harkening back to the original topic somewhat, I was reading this (http://www.cs.prince...out/command.txt) and any time I read neal stephenson I end up googling words and one of them I googled was 'epiphenomenon' (though the way he used it was more of the medical context) but this led me to the philosophical context, http://en.wikipedia....piphenomenalism which describes a good portion of my view on the manner. Maybe not all of it is relevant, but it's an interesting topic of debate maybe
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### #128 Use the Force

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Posted 23 December 2010 - 04:46 AM

But if the world is deterministic, then that means that we could predict the future, given all the relevant prior facts. We could build a model of the Universe and watch it play out, if we had all the data points to start it. I think that that is in part what unreality is saying.

...

I see unreality is giving up on his own argument...but it seems to me that if a system is deterministic, then it must be possible to build a model of it, given the relevant data. Can anyone think of a system that while deterministic, couldn't be modeled?

A system that you're a part of. We wouldn't be able to create a model of the universe and use it to watch the universe play out because we and that machine are part of the universe. The machine would have to predict what it itself was going to predict.

It would definitely be possible for some god or something outside the universe to calculate the future if the universe was deterministic, but from inside the universe we couldn't make such a calculation even if the universe was deterministic.

I notice that this is a different reasoning than unreality provided.

Yes - any deterministic system that keeps itself "blackboxed" in a way. I'm sure my understanding of Heisenberg's uncertainty principle is very very very lacking - and I really should read up on it a lot more because I seem to mention it a lot haha - but even if physics is deterministic, the "algorithm" so to speak that computes the next time-step of the universe from the previous one is hidden to observers. Or maybe not the algorithm (the laws of physics?) but rather the data itself (position/momentum of particles a la heisenberg). So even if the algorithm is known (or for that matter, really simple) we can't compute if we lack the data.

That would certainly be a problem too. But, even if we were aware of what the algorithms/laws of physics were that were governing our universe and even if we had a way of determining the exact position/momentum of all the particles in the universe, it would still be impossible to calculate the future of the universe from within the universe at a rate equal to or faster than the passage of time in the universe. It would produce a paradox if you could do such a thing.

But harkening back to the original topic somewhat, I was reading this (http://www.cs.prince...out/command.txt) and any time I read neal stephenson I end up googling words and one of them I googled was 'epiphenomenon' (though the way he used it was more of the medical context) but this led me to the philosophical context, http://en.wikipedia....piphenomenalism which describes a good portion of my view on the manner. Maybe not all of it is relevant, but it's an interesting topic of debate maybe

Interesting, I was just reading the Wikipedia article on Epiphenomenalism less than a month ago! A friend had posted an interesting essay on the subject on Facebook that he said "shook me right out of physicalism". I hadn't really thought about the subject before so of course I read the essay and then wrote a few pages on his wall about it. Here's the link: http://instruct.west...nal_qualia.html

I ended up partially disagreeing with him and the essay. I ended up deciding that physicalism was false, but concluded that the term was meaningless with its current definition and thus should either be modified or discarded. I couldn't think of a purposeful modification, so I really just left it at that. I think it's an interesting subject, so if you would like to discuss it I would definitely enjoy it.

I could definitely share the argument I put on my friend's wall January 29 - December 2 also. That's quite recent!

I'll take a look at that "In the Beginning was the Command Line" soon. Whatever it is, I'm sure it will be interesting. Out of curiosity, what are you planning on majoring in in college, unreality? Computer science?
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### #129 Use the Force

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Posted 23 December 2010 - 04:57 AM

EDIT for my above post: I meant November 29 to December 2!
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### #130 unreality

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Posted 23 December 2010 - 05:15 AM

A system that you're a part of. We wouldn't be able to create a model of the universe and use it to watch the universe play out because we and that machine are part of the universe. The machine would have to predict what it itself was going to predict

It would definitely be possible for some god or something outside the universe to calculate the future if the universe was deterministic, but from inside the universe we couldn't make such a calculation even if the universe was deterministic.

That would certainly be a problem too. But, even if we were aware of what the algorithms/laws of physics were that were governing our universe and even if we had a way of determining the exact position/momentum of all the particles in the universe, it would still be impossible to calculate the future of the universe from within the universe at a rate equal to or faster than the passage of time in the universe. It would produce a paradox if you could do such a thing.

Well said. Those are the conclusions I always come back to anytime I try to consider self-simulation.

This little story (I've posted it here before) is a fun read on the matter: http://everything2.c...node_id=1857290

Interesting, I was just reading the Wikipedia article on Epiphenomenalism less than a month ago! A friend had posted an interesting essay on the subject on Facebook that he said "shook me right out of physicalism". I hadn't really thought about the subject before so of course I read the essay and then wrote a few pages on his wall about it. Here's the link: http://instruct.west...nal_qualia.html

I ended up partially disagreeing with him and the essay. I ended up deciding that physicalism was false, but concluded that the term was meaningless with its current definition and thus should either be modified or discarded. I couldn't think of a purposeful modification, so I really just left it at that. I think it's an interesting subject, so if you would like to discuss it I would definitely enjoy it.

I haven't read the link nor even the entirety of the wikipedia article I posted, but it outlines a general thoughtline that I think is worth discussing: our bodies, our brains, etc, our physical self, reacts with neurochemistry and all the parts of the body working together. The self-aware "mind" exists as the "epiphenomenon" that thinks it has free will but of course is just observing what the physical brain is already computing and deciding.

I've brought that up before in this topic and for keeping spirits up (maybe just my own) usually end with something like "but it's not so bad for the Lazy-Bones paradox because the mind that seems to arise from the epiphenomenon-alism is that which 'agrees' with the brain such that the 'choices' the brain makes are (usually) what the mind wants as well". So it's kind of like your conscious mind is making choices although it's just an illusion. And sometimes your body makes choices for you, especially in situations where your epiphenomenon isn't equipped for it (like primeval fear/fight/flight responses or whatnot). Which seems close to what reality might be

I'll take a look at that "In the Beginning was the Command Line" soon. Whatever it is, I'm sure it will be interesting. Out of curiosity, what are you planning on majoring in in college, unreality? Computer science?

yup most likely

Edited by unreality, 23 December 2010 - 05:16 AM.

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