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What If Time Really Exists? (2008)

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Re: What If Time Really Exists? (2008)

#191

Post by thinkloop »

timcederman wrote: post #82
thinkloop wrote: post #51

Seems like a lot of the problem with "time" is semantic. Do things change? Yes, and if that's the definition then it certainly exists. But people don't generally see time like that, they think of it as some medium, or 4th dimension, that can possibly be traveled through. This kind of time does not exist (as much as anything can't exist). There are only particles and their positions. Traveling back in time would requi…

Time is very much a dimension. You should read up on relativity.

I don't know if physicists do it on purpose to get published, or whether they've drank too much of the kool-aid, but "dimension" is another one of those terribly overloaded terms. String theorists say that the universe may have 11 dimensions. So cool! I wonder what's in them!? Maybe my childhood puppy is there! But do you know what they mean? Only that one or more of their equations had an exponent of 11. That's it. There is no correlation or evidence of that translating to physical, or interesting, dimensions that we think of.

Re: What If Time Really Exists? (2008)

#192

Post by Achshar »

nobrains wrote: post #73

Those who say we live in simulation, are they saying that there is a creator(s)?

According to the theory, "they" just set the initial parameters (big bang one would assume) and let things happen. Intelligence is just one of the many random evolutions of mater states in a vast simulation of the universe.

It will be accelerated if for example we as humans start a similar simulation of our own. And inside that simulation some other intelligent life evolves. So likewise we may be n levels deep ourselves and never know any better.

Re: What If Time Really Exists? (2008)

#193

Post by stale2002 »

gus_massa wrote: post #115
stale2002 wrote: post #10

Earlier quoted context omitted.

The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.

> Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). This is a common misconception (¿among programmers?). Let's think about the double slit experiment. https://en.wikipedia.org/wiki/Double-slit_experiment In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wav…

Really? I was under the impression that the "observer" problem was still an open question.

How do we "know" that the camera collapses the wave function? Maybe WE collapse the camera by observing IT.

That's how you get things like Schrodingers cat.

Re: What If Time Really Exists? (2008)

#194

Post by echelon »

stale2002 wrote: post #193
gus_massa wrote: post #115

Earlier quoted context omitted.

> Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). This is a common misconception (¿among programmers?). Let's think about the double slit experiment. https://en.wikipedia.org/wiki/Double-slit_experiment In a classical word, you must simulate only one path. In a quantum word, you must simulate both. You don´t need some magical conscious observer to force the collapse of the wav…

Really? I was under the impression that the "observer" problem was still an open question. How do we "know" that the camera collapses the wave function? Maybe WE collapse the camera by observing IT. That's how you get things like Schrodingers cat.

> Maybe WE collapse the camera by observing IT.

That sounds ridiculous. The double slit experiment is a small system. The detector apparatus is much larger. The world outside of that, even more so. If your view is how the universe works, the number of superpositions of states that must exist between the "magical human observer" and the experimental result must be huge. Every particle in contact with every other particle. It seems ridiculous that the entire universe must be in superposition to give humans this special property.

The "observer" here is simply an outside system.

(FWIW, we only covered the basics of quantum mechanics in my chemistry undergrad. Perhaps a physicist can explain better.)

Re: What If Time Really Exists? (2008)

#195

Post by baytrailcat »

thinkloop wrote: post #188
witty_username wrote: post #175

Earlier quoted context omitted.

We can travel in it. We all are travelling in time and at different rates depending on our speed and gravity.

That's the sci-fi terminology and view that complicates and confuses the issue. Can reactions happen faster or slower, yes. No need to say "travel", that word has distinct meaning and connotations that lead to incorrect possibilities.

You have unknowingly stumbled into the heart of Special Relativity :) "travel" is the same all dimensions. If you think you are moving from (x1,y1,z1) to (x2,y2,z2) you are actually moving from (x1,y1,z1,t1) to (x2,y2,z2,t2). If you think you are staying put at (x1,y1,z1), then you are continuously moving from (x1,y1,z1,t1) to (x1,y1,z1,t2) to (x1,y1,z1,t3) and so on. The more you move in space, the less you move in time.

Also, when you put General Relativity in the picture, any sort of movement within this 4D space is possible (because the geometry of this space is wrapped) go to past, future, anything.

Re: What If Time Really Exists? (2008)

#196

Post by dingbat »

Tenoke wrote: post #126
stale2002 wrote: post #10

Earlier quoted context omitted.

The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Quantum physics looks a lot like lazy evaluation (State doesn't exist until "observed"). The speed of light seems like a hack to prevent an n squared problem of everything in the universe effecting everything at the same time.

>The simulation argument comes from the fact that there a quite a lot of physics effects that are both surprising, and look an awful lot like dirty hacks that a programmer might put it. Err, while this might be used to support the hypothesis, the popularized and most discussed version of the simulation argument doesn't even really mention this [0]. 0. https://en.wikipedia.org/wiki/Simulation_hypothesis

yeah i thought the simulation hypothesis is mainly coming from a probabilistic argument

Re: What If Time Really Exists? (2008)

#197

Post by thinkloop »

baytrailcat wrote: post #195
thinkloop wrote: post #188

Earlier quoted context omitted.

That's the sci-fi terminology and view that complicates and confuses the issue. Can reactions happen faster or slower, yes. No need to say "travel", that word has distinct meaning and connotations that lead to incorrect possibilities.

You have unknowingly stumbled into the heart of Special Relativity :) "travel" is the same all dimensions. If you think you are moving from (x1,y1,z1) to (x2,y2,z2) you are actually moving from (x1,y1,z1,t1) to (x2,y2,z2,t2). If you think you are staying put at (x1,y1,z1), then you are continuously moving from (x1,y1,z1,t1) to (x1,y1,z1,t2) to (x1,y1,z1,t3) and so on. The more you move in space, the less you move in…

Your comment perfectly crystalizes everything I'm trying to say. You explain the relationship of time to space very nicely and succinctly and correctly, however you decided to use the word "move", which comes with a lot of 3d baggage, which leads you to start thinking that "any sort of movement within this 4D space is possible". Nothing in relativity shows that freely moving back and forward in the time dimension is possible. The closest semblance is slowing your own time relative to other things you care about, so that, for example, you can have the body of a 30yr-old while earth is at 3000AD, but again that's not "traveling" around time, it's closer to putting food in the fridge so it spoils slower.

Re: What If Time Really Exists? (2008)

#198

Post by dghf »

gpsx wrote: post #187
dghf wrote: post #114

Earlier quoted context omitted.

> It's the most obvious counter-interpretation. More obvious than many worlds?

Yes. Many worlds is the single obvious solution. It seems some people don't understand many worlds though. Or maybe there is some other definition I am not aware. I want to describe my understanding here for people's benefit. The idea is that when you make an observation nothing special happens at all. For one, there is no wave function collapse. This is more an idea about how the observer experiences making a measur…

That was my understanding too. It's disappointing that it keeps getting explained along the lines of "every time there's a decision point at the quantum level, the universe splits in two", when it doesn't say anything of the sort (at least, not if I've understood it correctly).

Re: What If Time Really Exists? (2008)

#199

Post by ImTalking »

monktastic1 wrote: post #2

Between modern physics suggesting time and space may be illusions, leading technologists agreeing that we're almost certainly in a simulated reality, and many ancient traditions being certain that this is all an illusion, I may have to have to go ahead and take this seriously....

I think quantum physics and 'simulated reality' are one in the same. What's the difference between a reality which is only real when observed, and a reality which is only real when switched-on? What is the difference between a reality in which such reality is deterministic (ie. no free will (at the microlevel)), and a reality based on a pre-progammed algorithm?

Re: What If Time Really Exists? (2008)

#200

Post by stale2002 »

echelon wrote: post #194
stale2002 wrote: post #193

Earlier quoted context omitted.

Really? I was under the impression that the "observer" problem was still an open question. How do we "know" that the camera collapses the wave function? Maybe WE collapse the camera by observing IT. That's how you get things like Schrodingers cat.

> Maybe WE collapse the camera by observing IT. That sounds ridiculous. The double slit experiment is a small system. The detector apparatus is much larger. The world outside of that, even more so. If your view is how the universe works, the number of superpositions of states that must exist between the "magical human observer" and the experimental result must be huge. Every particle in contact with every other parti…

This issue is that what an "observer" is isn't defined.

According to your argument, a situation like Schrödinger's cat, where a Cat is both dead and alive, is completely ridiculous.

Which is a fair point. But apparently a whole lot of quantum physicists believe that Schrödinger's cat is a perfectly reasonable situation.

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