Entangled toy universe shows time may be an illusion • Hacker News Board

Re: Entangled toy universe shows time may be an illusion

#31

Post by mentos » Sat, Oct 26, 2013, 1:59 PM UTC

As a layman I don't understand the 'problem' with time?

To me, time is relative to 'timers'. So how I perceive the world passing is a function of a electro/chemical activity in my head. I'd imagine if you could somehow 'double' this function I'd perceive time at half the speed. And I imagine if you were to turn off my 'timer' the world would pass by instantaneously.

I've heard that 'time' is the fourth dimension? But again, as a layman, I have to ask why isn't 'thought' the fourth dimension? Isn't it only by being conscious, by being a 'timer', that 'time' can even be perceived?

Re: Entangled toy universe shows time may be an illusion

#32

Post by conformal » Sat, Oct 26, 2013, 2:13 PM UTC

sillysaurus2 wrote: post #2

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

the idea of unification you reference is more of a process of simplification, with an eye to creating additional explanatory value.

one of the best examples is that of the ptolemaic system of astronomy: prior to galileo speculating that the earth moved around the sun, everyone thought the earth was the center of the universe and that objects in the sky just naturally moved in non-linear spirals (epicycles) that needed endless corrections to be "correct". once galileo's system was applied, the complexity of making tons of extra corrections to track the path of some star was drastically reduced: these changes were now attributable to the earth's motion around the sun, and further the sun's motion in the galaxy.

you may be right that there is indeed an ultimate simplification, but nobody knows where the rabbit hole ends.

Re: Entangled toy universe shows time may be an illusion

#33

Post by officemonkey » Sat, Oct 26, 2013, 2:28 PM UTC

I told my son not to let the DC LEGO play with the Marvel LEGO. But did he listen? No.

Re: Entangled toy universe shows time may be an illusion

#34

Post by eru » Sat, Oct 26, 2013, 2:43 PM UTC

laander wrote: post #20

rosser wrote: post #4

Earlier quoted context omitted.

Because physicists believe in parsimony? Less flippantly, simply that if the two (on their own, staggeringly accurate) main theories we have about how the universe works are as fundamentally incompatible as the ones we've got, then there's probably something we don't yet understand about the thing they're describing. The search for a ToE isn't so much about "unifying" QM and Relativity as it is about figuring out wha…

I am blasted away by your completely staggering domain-knowledge and my lack of the same. Probably should stop seeing universe docus and study more science

Math is hard. And understanding real science often involves understanding math. (And docus almost never go into the math parts.)

Re: Entangled toy universe shows time may be an illusion

#35

Post by rnd33 » Sat, Oct 26, 2013, 3:06 PM UTC

mentos wrote: post #31

As a layman I don't understand the 'problem' with time? To me, time is relative to 'timers'. So how I perceive the world passing is a function of a electro/chemical activity in my head. I'd imagine if you could somehow 'double' this function I'd perceive time at half the speed. And I imagine if you were to turn off my 'timer' the world would pass by instantaneously. I've heard that 'time' is the fourth dimension? But…

Because time has a direction (for some reason it doesn't seem possible to go backwards though), and a value. I can't think of similar analogies for 'thought' that makes it fit with the other 3 room dimensions.

Re: Entangled toy universe shows time may be an illusion

#36

Post by deckiedan » Sat, Oct 26, 2013, 3:29 PM UTC

ChuckMcM wrote: post #9

Time is weird stuff. When you can tell what altitude your atomic clock is by the offset in its notion of time with the clock at your side, you start to get an inkling about that. The professor who taught quantum mechanics at USC when I was there used to joke that God told Adam and Eve that it took 7 days to create the universe, but we know from our observations that it was closer to 14 billion years. Given these two…

Technically, it was 6 days, and He rested on the 7th. :-)

Re: Entangled toy universe shows time may be an illusion

#37

Post by ddebernardy » Sat, Oct 26, 2013, 3:45 PM UTC

sillysaurus2 wrote: post #2

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

"It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit?"

Think of that question as akin to Hilbert second problem[1]: he wondered if the axioms of arithmetic were consistent -- back then, it seemed likely. Gödel came along and showed that no proof of it can be carried out within arithmetic itself. In a sense, the problem isn't entirely solved; but we now do know that we can't know. Perhaps someone will come along one day and give a similar answer in physics.

[1]: http://en.wikipedia.org/wiki/Hilbert's_problems

Re: Entangled toy universe shows time may be an illusion

#38

Post by nasht » Sat, Oct 26, 2013, 4:27 PM UTC

millstone wrote: post #13

sillysaurus2 wrote: post #2

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

Per my understanding, there's less concern over unifying, say, the strong and electroweak interactions. You have to posit some ridiculous coincidences to explain facts like why the charge on protons and electrons are exactly opposite, but nothing whatsoever prevents you from doing so. Then you get separate, compatible theories describing separate domains. That's basically what the Standard Model is: QCD + electroweak…

not sure if it is ok to ask this here, but does anyone know of a blog where physicists might be discussing this and other aspects of time?

Re: Entangled toy universe shows time may be an illusion

#39

Post by nnq » Sat, Oct 26, 2013, 5:22 PM UTC

richardjordan wrote: post #6

sillysaurus2 wrote: post #2

Question: Why do some physicists believe it's a problem that physics isn't unified? It seems odd to assume that just because throughout history we've unified more and more concepts that all of physics can be unified. What if there's a limit? It's interesting to think that 100,000 years from now, physicists will still be working on the problem since no one would know it's impossible.

You either believe in natural or supernatural explanations for the universe. If you accept the latter then the discussion is moot. If you're a scientist your approach is the first. It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations ar…

> It is difficult, perhaps impossible, to come up with a philosophically sound logically consistent explanation for natural phenomenon which isn't unified and connected at a fundamental level

Well, one could come up with some kind of model of "infinite complexity", different models of different aspects of the universe can never be unified because of stretches of "infinite complexity" "between them", like imagine a model of particle physics with an infinite number of ever "smaller" particles and no fundamental particles/forces, things made of smaller/deeper things ad infinity. I guess our current mathematics is even capable of describing such a thing. But since "more knowledge" means "more advantages / chances of long term survival" for a species, it wouldn't matter if there is no finite upper bound of understanding, we will still pursue science. And such a point of view would only support theories that violate Occam's razor and the principle of parsimony, it wouldn't really help.

...but it would make for interesting philosophy, if the people smart enough to formulate such a theory mathematically would wast their time doing metaphysical philosophy :) And I don't even want to imagine how such a theory could be bent and twisted by popular interpretation and cult leaders looking for scientific support for whatever new "religions". But overall I think some paths of thought, like this one, are better let unexplored - too many dark and weird areas and too little of use for the advancement of science: we'd better keep our Occam's razors sharps and minds aimed at simple and consistent explanations ;)

Re: Entangled toy universe shows time may be an illusion

#40

Post by emhs » Sat, Oct 26, 2013, 6:04 PM UTC

sillysaurus2 wrote: post #8

richardjordan wrote: post #6

Earlier quoted context omitted.

You either believe in natural or supernatural explanations for the universe. If you accept the latter then the discussion is moot. If you're a scientist your approach is the first. It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations ar…

It is difficult, perhaps impossible, to come up with a philosophically sound logically consistant explanation for natural phenomenon which isn't unified and connected at a fundamental level. Two incompatible sets of natural explanations are vastly less likely than one unless we're falling back on superstition again. Really? Ancient philosophers argued that it's vastly less likely for there to be such a huge distance…

The key difference is that we no longer posit that we know everything. We assumed we knew things we didn't, in ancient times, and in the process relied on hand-waves to keep moving, until some scientifically minded folks got too frustrated with the inconsistencies and started to accept that perhaps we didn't know it all. Now we know we don't know, and use the inconsistencies to tell how close we're getting to knowing enough to have consistent understanding.

The key is that we continue to improve our ability to gather evidence about what the universe looks like, and insist that our theories keep pace with the evidence we're gathering. So, the previous hand-waves occurred in large part due to insufficient data, and unwillingness to look for more. We've moved past that, to a large extent.