Newsgroup: it.discussioni.misteri
Titolo: Sul perche' la meccanica quantistica e' quello che e'.

Le stranezze della meccanica quantistica sono effetti 
dell'ottimizzazione del codice usato per simulare il nostro universo.
 
(Not really, l'ho letto su Reddit ed e' troppo bello per non essere 
condiviso: 
<
https://www.reddit.com/r/AskReddit/comments/5foq14/if_were_all_living_i
 
n_a_computer_simulation_there/damxl3r/>
 
 
“Let me get this straight… you simulate an entire universe, just for 
this video game?”
 
“Well, not exactly.” Juup told the reporter, “We couldn’t simulate an 
entire universe, not really, without consuming an entire universe worth 
of matter and energy and by the time you get there, what’s the point?
“You know what happened in Azeraan when pirates started dismantling 
their galaxy… and that was just a few stars before it was utter chaos!”
 
“But you say the entire universe is available,” said the 
reporter, “users can travel anywhere within it, and it’s self-
consistent?”
 
“Yes, the entire universe is open to players. For the moment, we have 
about 7 billion active beta users, and we’ve kept them to one planet 
mostly. But they’re starting to explore their solar system, and we’re 
nearly ready to launch publicly, so we’re letting their expansion 
continue. Players will spread through the solar system and fill the 
galaxy, then spread to others across the universe.
“As to how the simulation works… well it’s a rather clever solution 
that a then-intern, now-partner came up with; it’s some clever math 
that allows us to statistically simulate the universe.”
 
“How does it work? You can get technical with me, our readers will love 
it.”
 
“So there’s obviously a huge cost, computationally, if you try and keep 
track of every particle, everywhere, at every time. You can either 
simulate and store the result, which takes massive memory, or you can 
re-simulate up to that point every time you need a value, which takes 
massive computation. The biggest sims (up until now) are about the size 
of a planet, but so are the computer systems needed to run them.
“Instead of tracking the actual position of each particle, we track 
particle probabilities over a configuration space. The math defining 
the configuration space is so efficient, we can run a dense universe on 
the same planet-class computer as the smaller sims.”
 
“And this configuration space, it’s true to the real world?”
 
“For the most part. That is, to a casual observer, yes, it looks the 
same.
“In fact, the beta players worked out all our standard laws of physics 
within the simulation, they call them “Newtonian physics”, before they 
started to notice the small inconsistencies. It really feels very 
natural, I’ve heard.”
 
“Sounds unreal, or real, I guess. What are these inconsistencies 
though?”
 
“It’s little things, you wouldn’t notice most at first, until you start 
making experiments with specialized equipment.
“In this world, particles aren’t just particles, they can also move 
like waves, because we only track a continuous probability of where 
they are. But the waves don’t move instantaneously, the way they do 
here in reality. Well, that’s not entirely true; from the perspective 
of the wave it’s instant, which keeps things looking consistent, but 
from any other perspective, the waves move at a constant speed. It 
actually lets you separate out different frequencies optically, which 
gives rise to probably the most spectacular and obvious deviation 
between the sim and reality… rainbows.
“There are other effects too, you can only move at the speed of this 
propagation. It hasn’t really had an effect yet on our beta users, 
except for those experimenting on it to figure it out, but we expect 
that as they expand across the first galaxy, it will begin to have 
political consequences, since it will limit trade and even 
communication to somewhat local groups.
“Some other weird effects:
A particle is never in one place, you can never measure it’s exact 
position and velocity. 
If you approach the velocity limit, you get heavier. 
Coefficients of Friction are no longer properties of each material, but 
are instead joint properties of pairs of materials. Users have compiled 
enormous books of many of the possible combinations, unlike here where 
it’s a simple calculation based on each material’s composition. 
The speed limit requires small warpings of space-time, this creates 
some optical artifacts, complicates slightly trajectory planning, and 
it gives rise to a force they call gravity. The extra force we thought 
was a big flaw in using the statistical compression algorithm, but it 
fortunately turns out to be experienced in almost the same way as our 
attractivity force, though it depends on the mass of the planet. Only 
about 30% of planets will be habitable at their present masses. 
“Anyway, the inconsistencies are small. In this “quantum compression” 
that we do, to use a term the players use from within, anyway, in this 
compression, we’ve worked to balance the math so that all macroscopic 
effects are essentially unchanged from reality. “Newtonian physics” 
dominates our players usual experiences, it feels quite natural. It’s a 
bit like a compressed picture; you keep most of the image, and try to 
balance for the important details, but if you look close enough, you’ll 
start to see compression artifacts along the edges. Same thing here, 
99% realism, but 1% weirdness. Fortunately, a lot of players enjoy 
exploring the weirdness. They’re discovering and exploiting it, in 
weapons, energy generation, computation. We’re actually very curious to 
see what their limits are in-universe. We may soon find that they’re 
simulating something like us.”
 
“Great, thanks for your time. Can I play it now?”
 
“Yes, we’re pleased to announce that you, Janngop, of the Daily Times, 
will be our first user out of Beta. The players will soon reach out to 
mars, you can be part of the game’s first wave of players off the home 
planet.” 
 
 

 dell'ottimizzazione del codice usato per simulare il nostro universo.
 
L'idea sembra carina finche' uno non comincia a studiare
la MQ seriamente e si rende conto di quanto sia orrendamente
pesantissimo dal punto di vista computazionale simulare
esattamente anche una sola particella quantistica, figuriamoci
una decina o piu'. A quel punto l'idea che la MQ sia un
trucchetto per simulare piu' in fretta la meccanica classica
(semplicissima al confronto) si rivela per quel che e'.
Considero la validita' della MQ la migliore prova che abbiamo
che l'universo NON sia una simulazione.
 
UV

 planet.? 
 
Devo ringraziarti due volte per questo post: la prima per il
racconto stesso, molto simpatico :-), la seconda perché
è servito a far riapparire un certo raggio di luce ;-)
 
Bye, G.

 n_a_computer_simulation_there/damxl3r/>
 
Molto divertente, grazie!
 
-- 
Make a backup copy of your soul!
http://fuffologia.blogspot.com/
 

 n_a_computer_simulation_there/damxl3r/>
 
x chi non addetto ai lavori
puoi spiegare in modo semplice grazie