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Do we live in a computer simulation? How to test the idea.
KurzweilAINetwork ^ | December 13, 2012

Posted on 12/13/2012 6:21:49 AM PST by ExxonPatrolUs

The concept that we could possibly be living in a computer simulation comes from a 2003 paper published in Philosophical Quarterly by Nick Bostrom, a philosophy professor at the University of Oxford.

With current limitations and trends in computing, it will be decades before researchers will be able to run even primitive simulations of the universe. But a University of Washington team has suggested tests that can be performed now, or in the near future, that could resolve the question.

Currently, supercomputers using a technique called lattice quantum chromodynamics (LQC), and starting from the fundamental physical laws that govern the universe, can simulate only a very small portion of the universe, on the scale of one 100-trillionth of a meter, a little larger than the nucleus of an atom, said Martin Savage, a UW physics professor.

Eventually though, more powerful simulations will be able to model on the scale of a molecule, then a cell and even a human being. But it will take many generations of growth in computing power to be able to simulate a large enough chunk of the universe to understand the constraints on physical processes that would indicate we are living in a computer model.

However, Savage said, there are signatures of resource constraints in present-day simulations that are likely to exist as well in simulations in the distant future, including the imprint of an underlying lattice if one is used to model the space-time continuum.

The supercomputers performing LQC calculations essentially divide space-time into a four-dimensional grid. That allows researchers to examine what is called the strong force, one of the four fundamental forces of nature and the one that binds subatomic particles called quarks and gluons together into neutrons and protons at the core of atoms.

“If you make the simulations big enough, something like our universe should emerge,” Savage said. Then it would be a matter of looking for a “signature” in our universe that has an analog in the current small-scale simulations.

Savage and colleagues suggest that the signature could show up as a limitation in the energy of cosmic rays.

In a paper they have posted on arXiv, they say that the highest-energy cosmic rays would not travel along the edges of the lattice in the model but would travel diagonally, and they would not interact equally in all directions as they otherwise would be expected to do.

“This is the first testable signature of such an idea,” Savage said.

If such a concept turned out to be reality, it would raise other possibilities as well. For example, co-author Zohreh Davoudi suggests that if our universe is a simulation, then those running it could be running other simulations as well, essentially creating other universes parallel to our own.

“Then the question is, ‘Can you communicate with those other universes if they are running on the same platform?’” she said.

There are, of course, many caveats to this extrapolation. Foremost among them is the assumption that exponential growth of computers will continue into the future. Related to this is the possible existence of the technological Singularity, which could alter the curve in unpredictable ways.

And, of course, human extinction would terminate the exponential growth — or its simulation.


Silas R. Beane, Zohreh Davoudi, Martin J. Savage, Constraints on the Universe as a Numerical Simulation,, 2012, arXiv:1210.1847

Nick Bostrom, Are you living in a computer simulation?, Philosophical Quarterly, 2003

TOPICS: Chit/Chat
KEYWORDS: computer; matrix; sims; simulation
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To: ExxonPatrolUs
We have a virus!

Pls update anti-virus program.

21 posted on 12/13/2012 7:22:06 AM PST by TexasCajun
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To: TexasCajun

Was that picture from the first debate?

22 posted on 12/13/2012 7:30:00 AM PST by liberalh8ter (If Barack has a memory like a steel trap, why can't he remember what the Constitution says?)
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To: Lazamataz

I totally agree. I’ve read her work twice and what’s scary is some of it starts to make a little (very little) sense.

23 posted on 12/13/2012 7:47:06 AM PST by Portcall24
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To: PieterCasparzen

it’s pretty easy, as these things go, to demonstrate random disorder all over the place ~ this is the thesis that God not only throws dice with the universe, He throws them where even He can’t see them.

24 posted on 12/13/2012 7:53:45 AM PST by muawiyah
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To: ExxonPatrolUs

Just silly. We already know the answer is 42.

25 posted on 12/13/2012 8:37:23 AM PST by TexasRepublic (Socialism is the gospel of envy and the religion of thieves)
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To: ExxonPatrolUs

We all knew this already.
The programmer’s name is “I AM”.

26 posted on 12/13/2012 9:02:53 AM PST by RavenLooneyToon (Tail gunner Joe was right.)
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To: muawiyah

m, IMHO, what we think of as disorder, or randomness is lack of knowledge of the order of things.

For example, start with a barrel full of lottery numbers (Step A). Turn it by a handle (Step B) (conventional wisdom says this is “randomizing” the numbers), stop (Step C), then a hand reaches in and pulls out a number (Step D).

If one had precise information at Step A, and precise data on Steps B - D, one would know precisely which number was coming out of the barrel.

Randomizing is really just changing the order of a set of things and keeping the result unknown. The order of the set is then unknown.

If we look at the first few elements of a “random” set, and we see a pattern, then we can guess other elements. But if we see no pattern in our sample, we say ew, it’s random.

IMHO, what we really mean is we see no pattern and, since we only have a sample, we can’t infer anything about the overall order of the set.

IMHO, of course, because I’m sure there are rocket scientists who will offer dissertations on randomness (when simply a “no way”, “sorta” or “yeah” would suffice, perhaps with a link to their dissertation, since we can google for dissertations to our heart’s content; I’m just trying to generalize in a few occamesque paragraphs).

27 posted on 12/13/2012 9:48:23 AM PST by PieterCasparzen (We have to fix things ourselves)
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