Time Without Change

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Charlie!
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Re: Time Without Change

Postby Charlie! » Tue Sep 20, 2011 10:50 am UTC

Malconstant wrote:
Charlie! wrote:"what if our perceptions aren't coming from reality, but are instead generated by an evil demon?" is a totally valid question, it's just that reality is more probable than evil demons by Occam's razor.

Oh yeah? What's your measure? And never mind the Boltzmann brains.

My measure's about 6 feet.
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Re: Time Without Change

Postby Malconstant » Tue Sep 20, 2011 3:03 pm UTC

Charlie! wrote:My measure's about 6 feet.

Yeah, I hear everyone on the internet has one 6 feet long. (see what I did there? I went to penises)
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Re: Time Without Change

Postby Argency » Wed Sep 21, 2011 6:09 am UTC

As I understand it, the measure of suitability for hypotheses under Occam's razor is complexity: proposing an evil demon raises the total complexity of the model because it requires the demon to be more complex than the illusory universe it creates. Proposing the laws of physics, however, simplifies the model, because the laws of physics can be much simpler than the behaviour that arises from them.

The total data content of the second hypothesis can be compressed to initial conditions and universal laws, whereas the total data content of the first is actually higher than the amount of information in the universe, since we have to describe the actions of the demon creating our experiences, which is necessarily more complex than our experiences themselves.

EDIT: or was that not the question?
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Re: Time Without Change

Postby Charlie! » Wed Sep 21, 2011 12:04 pm UTC

Argency wrote:or was that not the question?

It's roughly analogous to the question :P Good explanation.
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Re: Time Without Change

Postby Malconstant » Wed Sep 21, 2011 1:36 pm UTC

Argency wrote:As I understand it, the measure of suitability for hypotheses under Occam's razor is complexity: proposing an evil demon raises the total complexity of the model because it requires the demon to be more complex than the illusory universe it creates. Proposing the laws of physics, however, simplifies the model, because the laws of physics can be much simpler than the behaviour that arises from them.

The total data content of the second hypothesis can be compressed to initial conditions and universal laws, whereas the total data content of the first is actually higher than the amount of information in the universe, since we have to describe the actions of the demon creating our experiences, which is necessarily more complex than our experiences themselves.


But the demon need only create my experience via matrixesque simulation, and to hell with the rest of the universe. So if the demon itself has a much simpler universe than the fake one being modeled, there you go. Does that really feel more complex to you than our infinite universe possibly multiverse with qm, relativity, brane theory, 11-dimensional string theory, etc., etc. Maybe our demon has a much simpler universe but a very creative mind.

Also with "measure" and "Boltzman brains" I was invoking a probability argument. What's simpler, a universe which appears to have evolved for billions of years to make everything as we see it, including human civilization. Or, that my brain and perception is a random fluctuation in a suitably large bath of hot plasma, and in just one half of a split second the surrounding plasma will flood my fluctuation and annihilate me. For that one all you need is randomly fluctuating stuff lying around long enough, is that not simpler?
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Re: Time Without Change

Postby Charlie! » Wed Sep 21, 2011 2:42 pm UTC

Malconstant wrote:Maybe our demon has a much simpler universe but a very creative mind.

To specify our observations within the scope of a "creative mind" still requires all the information of our observations, at the very least.

Malconstant wrote:For that one all you need is randomly fluctuating stuff lying around long enough, is that not simpler?
And "everything happens" is also simple. But if we're generated by a chaotic or all-encompassing process, then the amount of order we see in the world has probability near 0. The resolution is to not just use the most simple hypothesis - rather, we weight hypotheses by their simplicity and their probability on the same scale.
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Re: Time Without Change

Postby Malconstant » Wed Sep 21, 2011 2:57 pm UTC

Ah, so what's your probability measure then? 1 of 10^500? Perhaps a little anthropic + youngness + time delay biases? The whole point of Boltzmann brains is that their raw probabilities of creating an insanely unlikely fluctuation nevertheless totally dwarf the probability of having a universe as it seems to be.

And all of the information of my observations is very small compared to even all of the observations of all of the people on Earth, much less the rest of an infinite universe.
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Re: Time Without Change

Postby Diadem » Wed Sep 21, 2011 4:38 pm UTC

Malconstant wrote:The whole point of Boltzmann brains is that their raw probabilities of creating an insanely unlikely fluctuation nevertheless totally dwarf the probability of having a universe as it seems to be.

Exactly.

If our universe arose out of the particularly violent quantum fluctuation, as some have suggested, then such a quantum fluctuation is extremely unlikely. That is not a problem, given enough time. But a much smaller quantum fluctuation that just creates the illusion of a universe (ie a Boltzmann brain) is much more likely than a quantum fluctuation big enough to create an actual universe. Overwhelmingly more likely, in fact.

What the Boltzmann brain thought experiment really demonstrates is that we need a mechanism for universe creation. It can't have been a simple quantum fluctuation as we understand them currently. Because the probabilities do not work out. Well, that, or we really are Boltzmann brains. Who knows.
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Re: Time Without Change

Postby Charlie! » Wed Sep 21, 2011 5:32 pm UTC

Malconstant wrote:The whole point of Boltzmann brains is that their raw probabilities of creating an insanely unlikely fluctuation nevertheless totally dwarf the probability of having a universe as it seems to be.
If you start with a maximum-entropy universe and look for some numbers (is there a brain that looks like mine?) rather than others (of all brains, what is the probability they generate data that looks like mine?), sure. I haven't seen any satisfactory demonstration that if you actually keep your eye on the ball (that ball being probabilistic induction), you get Boltzmann brains.
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Re: Time Without Change

Postby gmalivuk » Wed Sep 21, 2011 10:32 pm UTC

Charlie! wrote:"what if our perceptions aren't coming from reality, but are instead generated by an evil demon?" is a totally valid question, it's just that reality is more probable than evil demons by Occam's razor.
What? Since when has Occam's razor said anything about probability?
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Re: Time Without Change

Postby Charlie! » Wed Sep 21, 2011 11:41 pm UTC

gmalivuk wrote:
Charlie! wrote:"what if our perceptions aren't coming from reality, but are instead generated by an evil demon?" is a totally valid question, it's just that reality is more probable than evil demons by Occam's razor.
What? Since when has Occam's razor said anything about probability?

If I say that by Occam's razor we should not believe there's a teapot in orbit between the earth and mars, that's a statement about probability - I assign a low probability to there being a teapot in orbit between earth and mars. This is because to assign it a high probability (higher than all mutually exclusive similar hypotheses, like it's actually a baby elephant) would be to pull information from nowhere, based on no data, and that's bad.

It's not a strictly traditional definition of Occam's razor, but it's probably a better thing to call it than "the don't pull information from nowhere principle."
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 12:31 am UTC

But you're not talking about a Russell's teapot scenario here, since that's actually a testable hypothesis that can potentially make a difference to our observations.

You're talking about a truly untestable claim.

Edit: Also, I assign a low probability to flipping 100 heads in a row, and yet if the coin is even slightly biased in favor of heads, this outcome turns out to have a higher probability than all the other mutually exclusive possible sequences of heads and tails that I might flip.
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Re: Time Without Change

Postby Argency » Thu Sep 22, 2011 12:55 am UTC

Malconstant wrote:But the demon need only create my experience via matrixesque simulation, and to hell with the rest of the universe. So if the demon itself has a much simpler universe than the fake one being modeled, there you go. Does that really feel more complex to you than our infinite universe possibly multiverse with qm, relativity, brane theory, 11-dimensional string theory, etc., etc. Maybe our demon has a much simpler universe but a very creative mind.

Also with "measure" and "Boltzman brains" I was invoking a probability argument. What's simpler, a universe which appears to have evolved for billions of years to make everything as we see it, including human civilization. Or, that my brain and perception is a random fluctuation in a suitably large bath of hot plasma, and in just one half of a split second the surrounding plasma will flood my fluctuation and annihilate me. For that one all you need is randomly fluctuating stuff lying around long enough, is that not simpler?


Ah, but for the demon to create the phenomena that we observe it has to imagine them, and therefore the universe in which the demon exists has to contain at least as much information as what ours appears to have, plus whatever extra information doesn't get through to us. You can't simulate a complex system within a simple one without increasing the complexity of the simple system to at least as high as the system you're trying to simulate. So even if the demon's universe operates on very simple laws which result in complex phenomena, those simple laws need to be at least slightly more complex than the simple laws we could hypothesize to govern our own universe.

Boltzman Brains, on the other hand, offer a much simpler generative system for the universe - unpredictable fluctuations. Crucially, however, to compress the data present in a series of unpredictable fluctuations is actually harder, since you can't reduce them to simple laws (if you could then they wouldn't be unpredictable). So either we can posit that Boltzman Brains to arise as a result of predictable fluctuations, in which case the universe can be reduced to simple laws (we just won't be able to discover them easily) or we can suggest that the fluctuations are unpredictable, in which case it's an even more complex hypothesis again.

Of course, it's totally arguable that the behaviour of the universe isn't reducible to simple laws, but doing that is begging the question, since it presumes that Occam's principle is wrong.
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Re: Time Without Change

Postby Malconstant » Thu Sep 22, 2011 1:28 am UTC

I wasn't trying to push Occam's razor with Boltzman brains. Just a good old multiverse probability measure argument. I like my Boltzmann brains statistical mechanically motivated. Got no problem thinking they run on every day physics, I'm not claiming the physics of them is simpler than the physics of our universe, merely that they are (in some models) vastly more plentiful and thus more likely to be the cause of our experience.

re: demon simulation. The nice thing about a demon simulation is that my experience can be the only thing in the universe. There is no need for the simulation to account for all of the rest of the information which our universe appears to have, only the really small amount of information required to account for my experience. And for that matter, I have yet to have an experience which really requires qm/relativity/string theory/what have you to make sense of. Especially if we're going demon simulation.
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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 2:36 am UTC

gmalivuk wrote:But you're not talking about a Russell's teapot scenario here, since that's actually a testable hypothesis that can potentially make a difference to our observations.

You're talking about a truly untestable claim.

Okay, then - how about a teapot having orbited the sun between earth and mars for a duration of 74 years, from 1800 to 1874. Would you say it's... unlikely?
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 3:48 am UTC

Would you say it's unlikely that this ever so slightly unfair coin I tossed 100 times between 1800 and 1874 came up heads every time? And yet, that is the single most likely sequence of tosses possible, out of all 2100 of the mutually exclusive scenarios.

And again, you are still making a claim that has physical meaning, even if now it's scientifically untestable. Which still makes it different from the reality vs. demon discussion. You are, for one thing, presupposing that the laws of the universe are as we think they are. So the improbability of the teapot derives from your premises, and not from Occam's razor.

The same is not true when discussing whether everything might be some kind of hallucination, because in allowing for that possibility we've thrown out all the premises about objective reality. There is no prior distribution to work with any more. There's no, "given what we know about the universe, what's the chance that ___", because we're supposing that we may not actually know anything about the universe.

I will grant that, in the case where we are presupposing a reality that behaves mostly as we think it does, Occam's razor tracks pretty well with probability. We can rule out a giant conspiracy about $topic using Occam's razor, for example, but not because additional complexity is inherently less probable. Rather, we rule it out because, given what we know about how people behave, there is a vanishingly small probability that so many people could be in the know for so long without a single one of them ever leaking real evidence of the conspiracy.
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Re: Time Without Change

Postby PM 2Ring » Thu Sep 22, 2011 4:52 am UTC

Argency wrote:Ah, but for the demon to create the phenomena that we observe it has to imagine them, and therefore the universe in which the demon exists has to contain at least as much information as what ours appears to have, plus whatever extra information doesn't get through to us.


Not necessarily - the demon's universe could have less total information than our universe. Your assumption holds if the demon has to model our whole universe at once in his brain, but why does the demon need to do that? If we assume that our universe is effectively separate to the demon's universe, rather than being a subset of the demon's universe, and that the demon isn't confined by the temporal structure of our universe, the demon could use a combination strategy comprising a low resolution global model of our universe supplemented by small high resolution local models generated on the fly. Most of the information for these local models doesn't need to reside in the demon's home universe, as it's stored in our universe.

Argency wrote:You can't simulate a complex system within a simple one without increasing the complexity of the simple system to at least as high as the system you're trying to simulate. So even if the demon's universe operates on very simple laws which result in complex phenomena, those simple laws need to be at least slightly more complex than the simple laws we could hypothesize to govern our own universe.


Why? If we assume that all the phenomena of the demon's universe and of our universe are computable, ie all phenomena can be calculated by a finite state machine in finite time, then the laws in both universes are equivalent to a universal Turing machine and both universes are representable as Turing-complete finite state automata. That doesn't take a lot of intrinsic complexity - even Conway's Life is Turing-complete.

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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 1:15 pm UTC

gmalivuk wrote:Would you say it's unlikely that this ever so slightly unfair coin I tossed 100 times between 1800 and 1874 came up heads every time? And yet, that is the single most likely sequence of tosses possible, out of all 2100 of the mutually exclusive scenarios.
Sure, it's the most likely single outcome despite its low probability. But this is irrelevant to my point. Or maybe it is relevant, since we're talking about the probability of something that's untestable :)

And again, you are still making a claim that has physical meaning, even if now it's scientifically untestable.
Meaning is what you make of it. It certainly has no impact on my observations. So what does "meaning" mean? It means that when I construct a 3d model of the solar system, I have a little teapot inside the model. "Meaning" is not about observations or physical reality, but about my model of the world. In a similar way, if I construct a 4d model of the universe, "time without change" means that I have a totally straight section of my model - meaning isn't a physical property of things ("oh yes, this red ball has 0.9 units of objective meaning" - or, more controversially, "life is inherently meaningful"), it's something humans do inside their heads.

Which still makes it different from the reality vs. demon discussion. You are, for one thing, presupposing that the laws of the universe are as we think they are. So the improbability of the teapot derives from your premises, and not from Occam's razor.
The laws of the universe could contain a special term for teapots orbiting the sun. Nowhere did I assume this was impossible - just that it would require lots of information about teapots. I can understand how you neglected this, though, since it's so improbable :P
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 1:36 pm UTC

Charlie! wrote:Meaning is what you make of it. It certainly has no impact on my observations. So what does "meaning" mean?
It means, at the very least, that it could have had an impact on observations made at the appropriate time.

You seem to be conflating two different scenarios here.

1) We know the laws of the universe, and are choosing between two hypotheses: there was a teapot there or there wasn't. We pick the second because, according to those laws, it's highly improbable for a teapot to have been there.
2) We don't know the laws, and are choosing between two hypotheses: the laws require a teapot to have been there or they don't. We pick the second because it's a simpler explanation that still accounts for all our observations and makes equally good predictions. Probability doesn't enter into it.

Indeed, probability can't enter into it, because we have no prior distribution from which to assign probability to competing untestable explanations for the laws of the universe. Unless, of course, you want to violate your own "don't pull information from nowhere" principle.

In particular, you're assuming a prior distribution. But if I flip a coin 5 times, and it comes up heads every time, and I ask you the probability that it's a fair coin, what do you say?
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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 3:42 pm UTC

gmalivuk wrote:It means, at the very least, that it could have had an impact on observations made at the appropriate time.
But it didn't. In a deterministic universe, it not having had an impact on our observations is equivalent to it not being possible, given that model of the universe. That is to say, the hypothesis made it impossible - if the hypothesis right up-front stated "it doesn't have an impact," that statement would be redundant. "Could have" refers to permutations of the model of the world, but an essential part of the problem is that we're holding the model constant.

we have no prior distribution from which to assign probability to competing untestable explanations for the laws of the universe
We do have some symmetries - scale-invariance gives you an exponential distribution, since there's no big sign telling us what units to measure information in. You should write your theory in terms of observations, rather than, say, defining "dogs" as a primitive that takes 4 bytes to write, though I think this might rely on the assumption that observations reflect a unique reality. I'm not sure how to determine the length scale for the exponential, but this is certainly a much smaller problem than having no idea what to do, and you can get some good qualitative results out of just the symmetries.
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 4:46 pm UTC

Charlie! wrote:
gmalivuk wrote:It means, at the very least, that it could have had an impact on observations made at the appropriate time.
But it didn't. In a deterministic universe, it not having had an impact on our observations is equivalent to it not being possible, given that model of the universe.
What? If I shake a box of dice, let them settle, and then shake it again before looking at them, you seem to be saying that every possible result of the first shake was not possible, since none of them actually had an impact on our observations at the time.

Which can't possibly be what you're saying, so would you care to rephrase more clearly?

We do have some symmetries - scale-invariance gives you an exponential distribution
Are we sure we have those symmetries? Maybe the demon is just making you think so, and hiding from you the sign telling you what units to measure information in.

You should write your theory in terms of observations
On what are you basing this "should"? Are you making a probabilistic argument on this point as well?

The coin that came up heads 5 times: is it a fair coin?
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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 9:08 pm UTC

gmalivuk wrote:
Charlie! wrote:
gmalivuk wrote:It means, at the very least, that it could have had an impact on observations made at the appropriate time.
But it didn't. In a deterministic universe, it not having had an impact on our observations is equivalent to it not being possible, given that model of the universe.
What? If I shake a box of dice, let them settle, and then shake it again before looking at them, you seem to be saying that every possible result of the first shake was not possible, since none of them actually had an impact on our observations at the time.

Which can't possibly be what you're saying, so would you care to rephrase more clearly?
I'm saying that in a deterministic universe, saying it "could have" had an impact isn't a good way for classifying hypotheses, because, by determinism, it was never going to have an impact.

We do have some symmetries - scale-invariance gives you an exponential distribution
Are we sure we have those symmetries? Maybe the demon is just making you think so, and hiding from you the sign telling you what units to measure information in.
The symmetries are in the information we posses, not in the actual world - probabilities are about doing the best with the information you have. If you've flipped an ideal coin and are holding there in your hand, if I can't see it the best I can do is to say 50/50.

You should write your theory in terms of observations
On what are you basing this "should"? Are you making a probabilistic argument on this point as well?
Nah, I just phrased it as a regular argument - observations are unique in a way that making "dogs" a 4-byte primitive is non-unique. Minimizing information-from-nowhere is intimately connected to using symmetries, so using observations is qualitatively a better way to describe theories than the "dogs" encoding.

The coin that came up heads 5 times: is it a fair coin?
It's certainly less likely to be fair than it was before you flipped 5 heads.

This sort of low-information problem relies heavily on the exact problem statement. Do I just know that it's "a coin, with some weightedness?" In that case no weight is special and uniform prior is the way to go. Do I have some indication, like it looking like a normal quarter, that's it's an ordinary unweighted coin? Everyday problems are often tricky because people take so much information for granted, and so reject the low-information solution as "unintuitive," when really they just didn't keep track of information.
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 9:32 pm UTC

Charlie! wrote:I'm saying that in a deterministic universe, saying it "could have" had an impact isn't a good way for classifying hypotheses, because, by determinism, it was never going to have an impact.
Then you still seem to be saying it isn't a good hypothesis to claim that those dice didn't all come up sixes.

Charlie! wrote:
The coin that came up heads 5 times: is it a fair coin?
It's certainly less likely to be fair than it was before you flipped 5 heads.
But the coin hasn't changed at all. It's still either fair or it isn't.

This sort of low-information problem relies heavily on the exact problem statement. Do I just know that it's "a coin, with some weightedness?" In that case no wight is special and uniform prior is the way to go. Do I have some indication, like it looking like a normal quarter, that's it's an ordinary unweighted coin?
None of that was specified. I guess you'll have to pull information from nowhere to make any decision, then?
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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 10:34 pm UTC

gmalivuk wrote:
Charlie! wrote:I'm saying that in a deterministic universe, saying it "could have" had an impact isn't a good way for classifying hypotheses, because, by determinism, it was never going to have an impact.
Then you still seem to be saying it isn't a good hypothesis to claim that those dice didn't all come up sixes.
One man's modus ponens is another man's modus tollens - I'm arguing that you shouldn't require hypotheses to have an impact in order for them to be "valid," or "make sense."

Charlie! wrote:
The coin that came up heads 5 times: is it a fair coin?
It's certainly less likely to be fair than it was before you flipped 5 heads.
But the coin hasn't changed at all. It's still either fair or it isn't.
It's like if you flipped a coin and covered it with your hand. The coin is already 0 or 1 with probability 1. If I assign P(heads) = 0.5, that isn't because the coin is literally half-heads. What it means is that my information is symmetrical between heads and tails. When you reveal the coin, now suddenly my probability estimate changes, even though the coin didn't change at all. What changed was my information.

This sort of low-information problem relies heavily on the exact problem statement. Do I just know that it's "a coin, with some weightedness?" In that case no wight is special and uniform prior is the way to go. Do I have some indication, like it looking like a normal quarter, that's it's an ordinary unweighted coin?
None of that was specified. I guess you'll have to pull information from nowhere to make any decision, then?
Are you being intentionally annoying?

ADDED: In a real situation, we conventionally assume that agents know what they know. And so if you say "But if I flip a coin 5 times, and it comes up heads every time, and I ask you the probability that it's a fair coin, what do you say," I cannot give a realistic answer because I don't know what I hypothetically know. Do you just walk up to me, a stranger, on the street and accost me with "what is the probability that it's a fair coin?" Do you tell me that you flipped the coin 5 times? I could average over these possibilities, weighted by an ignorance prior, to obtain some unrealistic answer. But generally when people pose this question, they are thinking of a specific situation, or perhaps even looking to apply probability theory to the real world. If you're merely trying to make things annoying for me, I'm reluctant to detail every single step of averaging over the various kinds of information I can think of, since it's not what you'd really want - you wouldn't actually give a shit about the answer, so why should I?
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 10:37 pm UTC

Charlie! wrote:Are you being intentionally annoying?
Only to the extent that you're intentionally missing the point. Which is that you have no basis to estimate the relative probability of an evil demon universe versus a real universe.
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Charlie!
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Re: Time Without Change

Postby Charlie! » Thu Sep 22, 2011 10:48 pm UTC

I have added my reasons for being annoyed in an edit.
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Re: Time Without Change

Postby gmalivuk » Thu Sep 22, 2011 11:12 pm UTC

Well I'm equally annoyed by your continuing contention that we can rationally assign probabilities to the hypotheses that we're hallucinating everything or being deceived by a demon or whatever.
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Pez Dispens3r
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Re: Time Without Change

Postby Pez Dispens3r » Fri Sep 23, 2011 11:42 am UTC

Charlie! wrote:You can't have an observed time without some coordinate "t" chugging away in the background, which already has the perfectly serviceable name of "coordinate time" or just "time." Dunno what's so bad about primitive notions. Maybe they're too understandable?

Can we have co-ordinate space, too? Can you show me a point in the universe with an absolute x-y-z co-ordinate, one by which the universe moves around as it remains fixed? Because you're suggesting an absolute time, one which observed times are dependent on and one which doesn't need to be measured for us to determine that it exists. This is unlikely.

Charlie! wrote:Don't bother reading any books on my account - I just figured you'd look it up on wikipedia. If you'd like to promise me to read things, though, you might read this article and any you find necessary to understand it.

My point was that you're dropping specific concepts without bothering to explain that they aren't general concepts. And that you're not explaining your specific concepts when you're called upon to do so, which implies you don't understand the concepts you're evoking (or at least that you're unwilling to betray the limits of your understanding by attempting to explain). I mean, how did you figure I'd look it up on Wikipedia? It's such an abstract point I only thought to search it because you have a history of being obtuse.

Charlie! wrote:Anyhow, in spacetime, a totally non-interacting system would just look like a collection of perfectly straight, parallel lines. Normally, atoms in a block of wood are dancing around, and photons are whizzing off in all directions, which look like twisted, wiggly, and non-parallel lines in spacetime. A bunch of perfectly straight parallel lines would mean that everything was frozen in space for some distance in the time-dimension. That's how "time without change" could be described. The only trouble is that as a hypothesis it's about as useful as "what if, like, it's all a dream?"

I asked you earlier: in the situation, how would we ever determine co-ordinate time continued as the universe remained fixed? How could we show it? Because it seems to be the utility of this hypothesis is that it can illuminate to us where we might hold conceptual misunderstandings to heart.
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Re: Time Without Change

Postby makc » Fri Sep 23, 2011 11:58 am UTC

mfb wrote:Try to define "stops", and you get your answer from that definition.
If you get something to say "it stopped", time passes.
If you do not, nothing stops and there is no question what times does.
Short and to the point. Where is *bow* emoticon?

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Re: Time Without Change

Postby Charlie! » Fri Sep 23, 2011 3:11 pm UTC

Pez Dispens3r wrote:Can we have co-ordinate space, too? Can you show me a point in the universe with an absolute x-y-z co-ordinate, one by which the universe moves around as it remains fixed?
Yeah, sure. I hereby define myself to be 0,0,0 in my coordinate system!

Because you're suggesting an absolute time
Nope. I hereby define myself to be (0,0,0,0) in my coordinate system!

My point was that you're dropping specific concepts without bothering to explain that they aren't general concepts. And that you're not explaining your specific concepts when you're called upon to do so, which implies you don't understand the concepts you're evoking (or at least that you're unwilling to betray the limits of your understanding by attempting to explain). I mean, how did you figure I'd look it up on Wikipedia? It's such an abstract point I only thought to search it because you have a history of being obtuse.
I'm sorry if I haven't been able to explain things to your satisfaction. Certainly in referencing grue and bleen I didn't unpack enough. But in many cases you seem to be demanding that I not use any concepts you might maybe not understand. If you don't understand the necessary material, wikipedia is a great resource, and there are many other places you can look too.

I asked you earlier: in the situation, how would we ever determine co-ordinate time continued as the universe remained fixed? How could we show it? Because it seems to be the utility of this hypothesis is that it can illuminate to us where we might hold conceptual misunderstandings to heart.

And I answered that there would not be a way to show it. And so, as a complicated hypothesis, it is of course eliminated by Occam's razor. But we don't say that it's impossible - it's entirely possible that we're in the matrix or something. We just say that it's too complicated and eliminated by Occam's razor.
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