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A growing number of scientists are convinced the future influences the past

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Re: A growing number of scientists are convinced the future influences the past

#261

Post by ben_w »

klipt wrote: post #224
0xBABAD00C wrote: post #134

Earlier quoted context omitted.

Here's the analogy, per Sean Carroll [1]: - There seems to be a special direction "down", where things fall by default, because we live in the vicinity of an influential object in space, called Earth - There seems to be a special direction "forward in time", where things happen by default, because we live in the vicinity of an influential event in time, called Big Bang If we had stuck to the local Earth context and g…

Right, entropy can decrease, just with low probability, which you can calculate using the Fluctuation Theorem: https://en.wikipedia.org/wiki/Fluctuation_theorem Perhaps given infinite time, we will randomly get back to a low entropy state infinite times, but I don't know enough about the math to say for sure.

You can, but that inevitably leads to far more Boltzman brains than things like the universe, and that's disastrous because then you should expect to be a Boltzman brain yourself, but they're configured randomly so if you are a Boltzman brain you can't trust any belief you have about reality including the maths that says you should be a Boltzman brain.

It's basically a softer version of Russell's paradox but for cognition and reality.

Re: A growing number of scientists are convinced the future influences the past

#262

Post by explaininjs »

marcus_holmes wrote: post #225
explaininjs wrote: post #91

Earlier quoted context omitted.

Scott Aaronson's "Ghost in the Quantum Turing Machine" tackled this question in a way I found enlightening. It's a bit of a dense read (I needed a plane trip to sit down and focus on it), but it presents a compelling case for the possible reversal of time arrows when it comes to the effects of quantum indeterminism on macro scale interactions. In short: what if humans, somehow, someway, have the ability to "influence…

That seems crazy - that my decision to have a ham sandwich for lunch had to be propagated all the way back to the start of the universe in order to happen ;) And yes, provability is a major problem with all these kinds of theories. We don't have a parallel universe handy as a control, and just saying "I am not going to have a ham sandwich tomorrow" isn't a viable experiment.

I interpret it as a sort of entropic antennae... each person (brain? qbit?) is tuned into what might be considered an allocated "entropy bandwidth". Some decisions, like whether you eat a ham bandwidth tomorrow utilize* practically none of that bandwidth. Others, what you might consider "major life decisions" might utilize* a ton of bandwidth. Some people might be gifted with a "larger" antennae, allowing them to utilize* a higher amount of entropy per second, or per lifetime. We might call these great artists, or generally any genius-level intellectuals. Alternatively, bat-shit crazy people.

*: On "utilize". A central debate (the central debate?) seems to be what sort of "state access mechanism" this maps to in our lexicon: "{reading|writing} {global|local|shared} {bandwidth|memory}"

Re: A growing number of scientists are convinced the future influences the past

#263

Post by resource0x »

7thaccount wrote: post #207
resource0x wrote: post #169

Earlier quoted context omitted.

If the direction of time is reversed, the eggs become whole again, but your memory of them once being scrambled is reversed, too, so you don't notice anything unusual. (It's like a rollback of database transaction, where not only the database state, but also the state of everything, including your brain, is getting rolled back)

But is there any evidence of that? Or is it just a thought experiment? I need to read more of the article, but appreciate you giving me some food for thought.

It's a thought experiment, of course. There cannot be any evidence one way or the other, by definition. Any potential evidence is rolled back, too. But then, why are we so sure our current beliefs WRT the arrow ot time are true?

Though there's no hard evidence, but if you think, for example, about the efficiency of evolution - it would be much easier to explain if we assume that the unlimited number of iterations is performed. (This is not the only possible explanation, of course- but this one is overlooked IMO)

I would say that compared with the strange ideas like "multiverse", this one is rather benign :-)

Re: A growing number of scientists are convinced the future influences the past

#264

Post by mkl »

novaRom wrote: post #230
nextaccountic wrote: post #132

Earlier quoted context omitted.

> I can explain that without the math by pointing out that if you took a video of a ball being thrown up and caught and played it in reverse, it would still depict a ball being thrown up and caught. That's amazing, thanks. The portion where you caught the ball in forward time is equivalent to throwing the ball in reverse time. I need to rewatch Tenet some day

I watched it 4 times. Only then I started to understand what's happening. How great and unique this movie really is.

I felt like I understood it the first time, but didn't think it was very good. Was that your initial reaction?

Re: A growing number of scientists are convinced the future influences the past

#265

Post by Apocryphon »

icegreentea2 wrote: post #112
Apocryphon wrote: post #69

Earlier quoted context omitted.

Is it the same thing as the holographic universe theory that was in vogue a couple of decades ago? https://i.pinimg.com/originals/27/d7/8c/27d78c9c3ee93c13eda4...

No. The block universe is that 3+1D spacetime "exists all at once". We just happen to experience travelling through it in one way. Holographic universe is that the physics and information in a 3+1D space time could be encoded into a 2+1D universe (with it's own physics).

Ah, Discover had an issue about that as well

https://www.discovermagazine.com/the-sciences/from-here-to-e...

https://i.ebayimg.com/images/g/xH8AAOSwryZi3Ef0/s-l1600.jpg

Re: A growing number of scientists are convinced the future influences the past

#266

Post by ben_w »

whatshisface wrote: post #114
sidlls wrote: post #108

Earlier quoted context omitted.

It isn't because we have the observations we have. It might be mathematically easy to invert time, but empirically it's not so simple. Mathematical symmetries and expressions are nice, but then the actual physical consequences and requirements (e.g., material, time, energy inputs) sort of force one's hand. Also, geocentrism is actually disproven by numerous observations, which in fact guided the mathematical formulat…

> Also, geocentrism is actually disproven by numerous observations, which in fact guided the mathematical formulation of our current physics. The validity of a coordinate system with the earth stationary at the center is guaranteed by the general principle of relativity. To get the stars to circle around it you would add a radially increasing potential in classical mechanics, or some coordinate shenanigans in GR. The…

> I know it sounds hard to believe, but if you're willing to bite the bullet that "the center of the universe" has no physical meaning, then earth can't be not the center of the universe any more than it can be.

I disagree.

The sentence «"the center of the universe" has no physical meaning» requires that Earth can't be at the center of the universe, because there isn't a center for it to be at.

You're still allowed any or many arbitrary zero-points, but that's only the center of a number line, nothing else.

Re: A growing number of scientists are convinced the future influences the past

#267

Post by didericis »

mikewarot wrote: post #253

Recently, I came across the Feynman-Wheeler handshake[1-ish], which lead to the Transactional Interpretation[2] of quantum mechanics, which lead to the Afshar experiment[3] I've come to conclude that all of these are consistent, but that they are a metaphorical truth , in that you shouldn't interpret them as literal truth. Gun safety advocates teach "All Guns are Loaded", another metaphorical truth. If you behave as…

This comment will probably give you hives, but the inability to interpret things like QM literally and the inability of the left brain to process things holistically seems relevant to the interpretability problem. See Iain McGilchrist's "The Matter with Things". (I promise it's less woo-woo than it appears)

Re: A growing number of scientists are convinced the future influences the past

#268

Post by kergonath »

ashirviskas wrote: post #184
prerok wrote: post #177

Earlier quoted context omitted.

Well, of course not :) Entropy as direction of time just means that the chaos on the whole increases. So, to create an ordered structure, like a cell organism, the by-product is more chaos around it.

To add, life just speeds up the chaos by orders of magnitude, it's a perfect entropy catalyst.

I’d be shocked if that were the case, even only considering the Earth. The oceans and the atmosphere are full of entropy. So is the liquid outer core. And even if the mantle is not quite liquid, and even if the crust is mostly solid, these are huge in terms of volume and mass, much larger than the sliver of dirt we inhabit on top of them. So yeah, I really doubt we (collectively, all human beings) are changing the Earth’s entropy in any meaningful way.

Re: A growing number of scientists are convinced the future influences the past

#270

Post by mik1998 »

richardw wrote: post #223
ChancyChance wrote: post #195

It's an article about QM. On Vice. About a QM thought experiment. On Vice. Why would there be any expectation of scientific rigor whatsoever? "retrocausality, may seem like science fiction grist at first glance" Stop there, vice.

https://en.wikipedia.org/wiki/Ad_hominem

I think https://en.wikipedia.org/wiki/Michael_Crichton#GellMannAmnes... is applicable here.
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