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Why the Flow of Time Is an Illusion

nautil.us

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Re: Why the Flow of Time Is an Illusion

#141

Post by Vi0 »

Faark wrote: post #122
egjerlow wrote: post #113

Earlier quoted context omitted.

> I have those too, and no offense to you personally, but I call bullshit on both mine and your acquaintances. In case of people I know, there was not one situation for which I couldn't find a more plausible explanation - which usually boils down to that for enough trials, even the rare coincidences sometimes happen. Fair enough - this 'statistical argument' is a convenient explanation that can always be invoked, but…

I have a hard time following. I don't feel well read on the topic, but your argument seems to boil down to "our thinking is so awesome, it must be magical". This strongly reminds me of creation myths where humans desperately tried to separate themselves from all other nature. But in case I'm missing something, I'd be thankful for you answering the following few questions to get me back on track: - Do you believe that…

In order: There certainly could be. How would we know? What if the universe isn't deterministic? Certainly it's more pragmatic to assume that only what we can experience is real, but that doesn't make it true.

The belief that there could exist parts of reality that the scientific method can't explain does not require having specific examples.

Even if all of reality can be understood by physics, that doesn't mean it can be simulated.

If physical reality can be simulated, then you could simulate the physical reality that makes up a person.

There is no guarantee that your simulation of the physical reality of a person would respond identically to an actual person.

There's a large body of philosophy on this, but basically it comes down to life working out better if we all assume everyone else is conscious.

There probably can be two similar beings demonstrating identical behavior with only one being conscious. Depends on what you define consciousness as I imagine.

I happen to lean towards believing Science can explain reality and that consciousness is a physical phenomenon, but to claim that things categorically must be that way is unfounded.

Re: Why the Flow of Time Is an Illusion

#142

Post by frenchy »

ASalazarMX wrote: post #118
cobbzilla wrote: post #68

I find this quote fascinating: "What I think that means is there is no holy era of time. It emerged. If, in the distant future, we find ourselves in a universe where all the stars have burned out, and all the black holes have evaporated, and all the radiation has been diluted by the dark energy that expanded our universe, and all we have is some very cold bath of photons here and there—basically thermal equilibrium;…

That same quote confuses me. If there are no events to measure time, why does that mean that time stopped? Can't it keep flowing just as space keeps expanding regardless of measurement? More so, photon decay is not completely ruled out yet, so events could keep happening in that cold photon bath.

It has to do with what time means. A coloiquial understanding of time has almost everything to with the way our mind and our memories work.

Our mind and memories won't be of much use at the end of the universe, so we have to depend on a more scientific definition. The best scientific way of describing and measuring time outside of our minds basically comes down to measuring systems as they increase entropy. As the universe ages, and these systems approach maximum entropy, the ability to measure time, and the ability to describe in any concrete way what time means, becomes increasingly difficult.

Re: Why the Flow of Time Is an Illusion

#143

Post by frenchy »

Falling3 wrote: post #34
zikzak wrote: post #10

Earlier quoted context omitted.

This is true. You also need to take into account how each day is a smaller and smaller percentage of your life which might be why kids think summer vacation lasts forever but it flys by for parents.

This explanation comes up frequently in these discussions. It makes a certain amount of sense on its face, but is there any evidence that this actually affects our perception of time?

This isn't really evidence at all, but it's well known that as people age, it becomes more difficult to new memories, than it is to keep old ones[1], which is why you regularly get old people mixing up their current loved ones with old, dead people; and why "you can't teach an old dog new tricks".

If the passage of time in the human experiences is largely a function of the memories we make. It's not at all surprising that things seem to go faster as we age.

[1] There's common-sense explaination for this, but I don't think the exact mechanism is understood. It is widely observed though.

Re: Why the Flow of Time Is an Illusion

#144

Post by aassddffasdf »

obastani wrote: post #96
cobbzilla wrote: post #68

I find this quote fascinating: "What I think that means is there is no holy era of time. It emerged. If, in the distant future, we find ourselves in a universe where all the stars have burned out, and all the black holes have evaporated, and all the radiation has been diluted by the dark energy that expanded our universe, and all we have is some very cold bath of photons here and there—basically thermal equilibrium;…

I'm not an expert, but I don't think that quote is quite right. There is still a notion of time, there is just no notion of a direction of time. For example, if you go deep into empty space, then one patch of space looks just like the next one. That doesn't mean there is no longer a physical concept of space. Similarly, just because one point in time doesn't look very different from the next, doesn't mean that there…

We are in a pocket of high order/ low entropy (not high entropy).

Re: Why the Flow of Time Is an Illusion

#146

Post by TeMPOraL »

vinceguidry wrote: post #126
TeMPOraL wrote: post #124

Earlier quoted context omitted.

Computers can become non-deterministic in practice as soon as you botch your random number handling, or hook your input up to environmental noise. Is there anything suggesting the brain is non-deterministic in a theoretical way, not just the way computers are?

Deterministic means that given the same input, the system gives the same output. Computers would be useless if they were not deterministic. Hooking up random input to a deterministic process will give random output. Garbage in, garbage out. What you're asking is for computers to be rational. That given garbage input, it will produce intelligible output. Computers cannot do this unless you program them to. Human minds…

Thermodynamics is defined in a deterministic universe. It's only through sheer amount of states any interesting system could be in that entropy arises. Chaotic systems (as studied in mathematics) are deterministic too. Conway's Game of Life is indeed an excellent illustration of the concept - of how chaotic and "surprising" behavior can arise in a fully deterministic system.

> Human minds are non-deterministic in many, many, many ways. Hand the same input to the same mind and you'll get a different output every single time

That's not non-deterministic. That's simply stateful. Most human-made systems you interact with daily are stateful, so it's not exactly surprising.

When I say "deterministic in practice" vs. "deterministic in theory" I mean this: a system is deterministic in practice if you can actually predict its outputs based on its inputs with reasonable amount of effort. A LED hooked up to a switch and a battery is deterministic in practice. So is a program computing GCD on 32-bit integers. A system is deterministic in theory if it's deterministic, but actually predicting its outputs requires absurd amount of computation. Lorenz system and weather are two examples. So is protein folding and turbulent flow. I see no reason why a fly brain, a mouse brain, or a human brain wouldn't be such systems either. The entire universe could be one, if you subscribe to many-worlds interpretation of quantum mechanics.

Re: Why the Flow of Time Is an Illusion

#147

Post by TeMPOraL »

Zaphods wrote: post #127
TeMPOraL wrote: post #76

Earlier quoted context omitted.

> The idea that consciousness is an algorithm or a computer or a machine is an assumption that is extremely popular among people in the tech industry because it confirms their assumptions No, it's not because of that. It's because it is effectively a computer. Not in the vague sense of "it has stuffs connected to stuffs and there's electricity involved", but in the more specific sense that it takes inputs, produces c…

> It's because it is effectively a computer. Not in the vague sense of "it has stuffs connected to stuffs and there's electricity involved", but in the more specific sense that it takes inputs, produces complex outputs, has clearly identifiable hardware and indirectly identifiable software. It even has internal structure we're only beginning to understand, but that we know enough about to reasonably infer what comput…

> A car's horsepower is not in its carburetor, or its gas, or its manifold, because the horsepower of a car is what it can do, its an ability, a power. In the same sense the brain can compute, but that doesn't mean it is a computer.

A car's horsepower is in the engine. That's what an engine does. Burns fuel, provides work over time. Work over time is denominated in horsepower - or, in saner company, in watts. Categories like "engine" or "computer" are not excluding. That thing in the car can be "an engine", "a hunk of metal" and "an expensive paperweight" at the same time. Similarly, if brain can compute, it is a computer. It's also an organ.

> Humans have other abilities, such as imagination, that are not computational.

Evidence needed. Why would it not be computational? We can, and do, easily build imagination-like computations. A fuzzy search on a graph. A series of simulations with relaxed constraints and somewhat randomized initial states. They all resemble aspects of imagination; it's not a big leap to conclude that imagination is nothing but a more complex variant of such computations.

> It means you can fuzzily model the brain on a computer, but that model will have glaring gaps.

Models exist on a map, not in the territory. So do brains and computers. The territory is made of whatever sub-quark substrate the reality is made of. When you say "brain", what you're really referring to is a model, and a pretty black-boxy one. Viewing the brain as a computer is an attempt to apply a model that's little more transparent (and therefore more useful); as long as it matches observable evidence (and it does), it's the right thing to do.

Re: Why the Flow of Time Is an Illusion

#148

Post by klank »

cobbzilla wrote: post #132
klank wrote: post #84

Earlier quoted context omitted.

> if ... the entire universe is essentially one uniform mass, wouldn't that mass then collapse upon itself, in a kind of big bounce? de Sitter space is a vacuum solution for Einstein's field equations. What this means is that the stress-energy tensor is basically "canceled out" everywhere by the uniform energy distribution. That means no point in spacetime experiences any field influence. That means no gravity, that…

Is it not the case that energy has mass? Why wouldn’t this be equivalent to a uniform mass distribution?

I think you might be getting them switched around.

Mass is a form of energy. Energy is not a form of mass. Put another way, mass is always energy. Energy is not always mass.

Re: Why the Flow of Time Is an Illusion

#149

Post by empath75 »

DiffEq wrote: post #129
cobbzilla wrote: post #68

I find this quote fascinating: "What I think that means is there is no holy era of time. It emerged. If, in the distant future, we find ourselves in a universe where all the stars have burned out, and all the black holes have evaporated, and all the radiation has been diluted by the dark energy that expanded our universe, and all we have is some very cold bath of photons here and there—basically thermal equilibrium;…

Here is the crux. Time IS motion. We measure this motion of objects relative to one another by comparing their motion to a standard set of things in motion called a clock. There is nothing else to time except that; but it is real, as real as anything, it is not an illusion.

No clocks, no time, right?

Re: Why the Flow of Time Is an Illusion

#150

Post by empath75 »

jbay808 wrote: post #136
supergarfield wrote: post #108

Earlier quoted context omitted.

Speaking of this, does anyone know of an explanation for why the direction in spacetime in which entropy decreases is parallel to the time dimension (the one with a different sign in the relativistic metric) of spacetime? Maybe I'm missing something, but I've never seen a link made between the two.

As opposed to entropy decreasing as you travel, say, toward the galactic north? It's a good question. One answer could be the mostly spatially uniform initial conditions of the big bang. Also, a spatial entropy gradient would gradually diffuse over time to become uniform again. But in general, the arrow of time is a consequence of systems that store a memory of their pasts, which is possible because the past is lower…

Isn’t a black hole a spatial entropy gradient?
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