
Who here believes the universe is a computer simulation? - dsowers
Just out of curiosity, I wanted to see how many people here think the simulation theory of the universe is quite probable. If you're not familiar with it, here is a good synopsis: http://www.simulation-argument.com/simulation.html
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mcherm
I believe that it is a moot question.

Let me explain what I mean. Some people say that Ben Franklin messed up when
he named positive and negative charge -- that the charge which is on the
electron should have been called "+" instead of "-". Imagine legions of
physicists arguing back and forth over this issue, some vigorously defending
"=" and others advocating for "-". It would all be wasted breath: they are
just NAMES, and it doesn't MATTER which name you use. What matters is building
a transistor, which depends on understanding that it's electrons that carry
the charge, not on what the charge is called.

Similarly, any time that two MATHEMATICALLY equivalent theories both explain
the facts, I personally don't care which one is true... I don't want to spend
time debating it, and honestly I don't believe that one is more "true" than
the other. Is classical mechanics driven by Newton's laws or by the Lagrangian
"action is zero"? Both! Either one implies the other.

And this is how I view the question of whether the universe is a simulation.
Finding out the laws of our universe seems interesting. Finding out whether
those laws are implemented by a universe or a computer simulation of a
universe... there is no meaningful difference so I don't care.

~~~
MarkPNeyer
if we are in a simulation, we could possibly hack our way out of it.

i've thought for a while now that the "speed of light" limit is a result of a
distributed consesnus algorithm taking a bit of time to convergd.

also, quantum mechanical noiss is leakage current flipping bits in memory.

~~~
Juha
"if we are in a simulation, we could possibly hack our way out of it."

Interesting, software engineers know there are no programs without bugs. Some
weirdest things in physics like quantum entanglement may just be bugs in the
simulation :)

~~~
trentlott
They act more like quick fixes used to get it running on schedule

------
Aqueous
We'll never know. If the universe is a simulation then it's similar to a
virtual machine running on top of a hypervisor. The virtual machine doesn't
know that it's not a real machine unless its hypervisor tells it so. From
inside the virtual machine, there is no meaningful distinction to be made
between being a real machine and being a virtual one.

~~~
dexen
We could know. If we ever broke out, that'd be a definitive proof that there
is a layer above our reality.

To continue your VM and hypervisor analogy, there is a class of hacks in which
virtualized software breaks out of the VM and is able to observe and/or
mannipulate host. For example,
[http://www.theregister.co.uk/2008/02/25/vmware_critical_vuln...](http://www.theregister.co.uk/2008/02/25/vmware_critical_vuln/)

[edit]

Moreover, even without breaking out, it is -- in some cases, at least --
possible to detect presence of hypervisor by carefully timing computations.
Albeit those methods seem to depend on access to a timing source that is
reliable (i.e., outside of hypervisor's control). For example,
[http://www.cs.cmu.edu/~jfrankli/book_chapters/virtual_machin...](http://www.cs.cmu.edu/~jfrankli/book_chapters/virtual_machine_detection.pdf)

~~~
unconed
The hypervisor analogy is silly IMO, because it assumes 'hardware assisted
virtualization', i.e. that the simulated matter/instructions are implemented
simply by using real matter/instructions in their normal way, but in a
controlled environment.

For the general case of virtualization, breaking out of the simulation would
be as impossible for us as it would be for a video game character.

~~~
xkcdfanboy
If the computer running the simulation is on a network, and robots/spaceships
etc exist, we could break out onto other devices and recreate ourselves as
programmed robots.

------
Estragon
This is like asking whether god exists. Until there is some evidence one way
or the other, it is pointless to consider the question seriously. Though it's
worth noting that the total ignorance implied by the lack of evidence about
the purpose of the universe implies that any specific speculation on the
question is almost certainly incorrect.

Fun to think about, though. Have you read Greg Egan's _Permutation City_ or
_Diaspora_?

[http://gregegan.customer.netspace.net.au/PERMUTATION/Permuta...](http://gregegan.customer.netspace.net.au/PERMUTATION/Permutation.html)

[http://gregegan.customer.netspace.net.au/DIASPORA/DIASPORA.h...](http://gregegan.customer.netspace.net.au/DIASPORA/DIASPORA.html)

~~~
dsowers
I haven't. They look interesting. I'll check them out.

------
RodgerTheGreat
This seems to fail Occam's Razor. The argument boils down to "Our observations
are consistent with what we'd see if we were in a simulation, so we're
probably in a simulation" modulo some specious asymptotic extrapolation.
There's nothing _impossible_ about the idea that we're living in a computer
simulation, but unless the idea is falsifiable it does not constitute a
rational, scientific theory.

~~~
rm445
Perhaps it is falsifiable. Perhaps there is some object with a fractal
property that would be enormously expensive to compute, but that nature can
determine without computation. Perhaps such an object could be produced, and
it could be shown that its property would be of such near-infinite complexity
to rule out us running in a simulation.

Or perhaps I've just spouted some technobabble. The point is that we are at
such an early stage of thinking about such things that they may yet be put on
a scientific footing. And if we do find answers to age-old philosophical
conundra (the universe-simulation one not being much different to older
questions about what we can determine about reality) then any answers that
come will come from science, not philosophy.

~~~
dexen
_> and it could be shown that its property would be of such near-infinite
complexity to rule out us running in a simulation._

I believe a fractal is not a viable experiment.

You hinge the experiment on assumption any simulation would be bound by memory
size or time taken to compute. Practical constraints aside (matter and space
is quantized at very small scale, so the depth of computation is finite), I
don't believe we can just assume such limitations.

I believe memory shouldn't be a problem for a fractal, because properties of
the fragment you are trying to observe can be computed directly from equations
describing the fractal, never mind the scale.

As for time taken to compute, it is _not observable_. We don't know of any
reliable timing source outside of the hypervisor[1] to compare time taken for
computation to; the supposed VM is free to take as long as it needs to to
advance to compute state, before advancing one
<http://en.wikipedia.org/wiki/Planck_time>

* * *

It could be argued the <http://en.wikipedia.org/wiki/N-body_problem> of all
the celestial bodies already puts our _supposed_ VM to a good test ;-)

\---

[1] if we knew one, it would make the experiment moot, as we would have a
direct proof we're inside of a simulation ;-)

------
DizzyDoo
It's an interesting question, are we in a Matrix, or computer simulation, or
the slightly older theory from 1641 where Rene Descartes imagined an
omnipotent demon lying to him. Maybe I'm simplifying the question, but I
reckon it boils down to how do we know what we know? Am I sat in front of a
computer screen now, or do I just believe I am?

I'm not really a philosopher, at all, but the Oxford Companion to Philosophy
says:

"Do you know that you are looking at a... book right now rather than, say,
having your brain intricately stimulated by a mad scientist? The sceptic
carefully describes this alternative so that no experiment can refute it. The
conclusion that you really are looking at a book, however, explains the
aggregate of your experiences better than the mad scientist hypothesis or any
other competing views."

which I think makes sense to me. I've met one or two people who say they
believe that they live in a Matrix/Alien computer simulation, but observing,
they live as if they don't.

~~~
Aqueous
Kant had an interesting reply to Descartes.

He said that the "world of objects in themselves" - i.e. numinal reality, or a
reality independent of our perception - must exist in order for us to have
experience at all. The reason? We know that there is a reality because
something must persist between each one of our "computations" - our
perceptions - in order for us to be able to order our perceptions in time.

We just don't know anything about that reality besides that it exists.

To sum up: We do live in reality at some level. How many layers we are removed
from the bottom-most substrate,how many simulations-within-simulations we are
in, is something we might not ever know. Kant actually said we can't ever
know.

------
edcroft
"Any sufficiently advanced technology is indistinguishable from nature" Karl
Shroeder

[http://www.kschroeder.com/weblog/archive/2011/11/30/the-
deep...](http://www.kschroeder.com/weblog/archive/2011/11/30/the-deepening-
paradox)

------
maverickscholar
BELIEVES??? What is this? A religion?

You can suspect. (That's honest.) Then, not being intellectually lazy like
"believers," you have to apply the scientific method to test your suspicions.
(Note: Using philosophy and semantics is no proof at all. It's physics or
nothing. You could start with the double slit photons experiment.)

------
melling
Yeah, sometimes I think we're just some kid's high school experiment. God only
knows. :-)

I really wouldn't put too much time into this. Votes don't matter. Even if we
all agreed, it wouldn't matter.

I'd put more time into things that do matter.

------
lionhearted
It's a pretty compelling thought experiment... the largest implication would
be that there potentially would be some sort of "afterlife"-esque thing
possible if we are in a simulation. Either being simulated more often, or
possibly "promoted" to a layer above where we're currently at.

If it was true, and you wanted to exist some more, then it might be thinking
about what would be make you in-demand in the higher level up. Perhaps some
generalized broadbased creative knowledge combined, combined with an
interesting well-thought perspective, and good communication skills?

------
noodly
Not me. It boils down to the meaning of universe - if you define it as
everything, nothing outside it exists, as there's no outside, in particular
there can't be any machine, that simulates the universe, otherwise we wouldn't
call it universe. If you define universe as computable subset of everything we
have access to, it might be possible to simulate that universe, using
computing machine if this machine had access to enough resources outside that
universe to hold its state.

------
joejohnson
A while ago, this article was on HN:
[http://www.theatlantic.com/technology/archive/12/03/were-
und...](http://www.theatlantic.com/technology/archive/12/03/were-
underestimating-the-risk-of-human-extinction/253821/)

The article is based on an interview with Nick Bostrom, a philosophy professor
at Oxford. His thoughts on the computer simulation scenario are very
interesting. I've reproduced them below, but I recommend reading the whole
interview; it's very fascinating. From the interview:

"Can you explain the simulation argument, and how it presents a very
particular existential risk?

Bostrom: The simulation argument addresses whether we are in fact living in a
simulation as opposed to some basement level physical reality. It tries to
show that at least one of three propositions is true, but it doesn't tell us
which one. Those three are:

1) Almost all civilizations like ours go extinct before reaching technological
maturity.

2) Almost all technologically mature civilizations lose interest in creating
ancestor simulations: computer simulations detailed enough that the simulated
minds within them would be conscious.

3) We're almost certainly living in a computer simulation.

The full argument requires sophisticated probabilistic reasoning, but the
basic argument is fairly easy to grasp without resorting to mathematics.
Suppose that the first proposition is false, which would mean that some
significant portion of civilizations at our stage eventually reach
technological maturity. Suppose that the second proposition is also false,
which would mean that some significant fraction of those (technologically
mature) civilizations retain an interest in using some non-negligible fraction
of their resources for the purpose of creating these ancestor simulations. You
can then show that it would be possible for a technologically mature
civilization to create astronomical numbers of these simulations. So if this
significant fraction of civilizations made it through to this stage where they
decided to use their capabilities to create these ancestor simulations, then
there would be many more simulations created than there are original
histories, meaning that almost all observers with our types of experiences
would be living in simulations. Going back to the observation selection
effect, if almost all kinds of observers with our kinds of experiences are
living in simulations, then we should think that we are living in a
simulation, that we are one of the typical observers, rather than one of the
rare, exceptional basic level reality observers.

The connection to existential risk is twofold. First, the first of those three
possibilities, that almost all civilizations like ours go extinct before
reaching technological maturity obviously bears directly on how much
existential risk we face. If proposition 1 is true then the obvious
implication is that we will succumb to an existential catastrophe before
reaching technological maturity. The other relationship with existential risk
has to do with proposition 3: if we are living in a computer simulation then
there are certain exotic ways in which we might experience an existential
catastrophe which we wouldn't fear if we are living in basement level physical
reality. The simulation could be shut off, for instance. Or there might be
other kinds of interventions in our simulated reality."

~~~
dsowers
Thanks for the clear breakdown.

------
Nuss
This universe is a simple computer program. Starting from the building blocks
of life. Hydrogen has one proton and one electron, Helium 2, Lithium 3 and so
on.. Adding one proton changes the whole element. Mixing these makes the whole
universe. What we see as solid is 99% empty space. What we think we see is 1%
of the visual spectrum. Soooo i wouldnt even bother thinking. We dont even
exist.:)

------
jamespitts
A computer simulation of what? A universe?

How about this: the universe is an artificial life machine aimed at generating
some interesting diversity. The intention is that the slime on planets begin
performing galactic-scale engineering. Yes, we're a brilliant ant farm in
God's den.

------
daniel-cussen
Anybody else who's played Minecraft :)

I've toyed with the idea, with the notion that the laws of physics are written
such that it's easier and cheaper to simulate the universe.

But then one would have to ask, If the universe is a simulation, what is the
seed number?

~~~
Ygg2
42?

~~~
daniel-cussen
Oh My God.

------
hoylemd
I believe it. I think that the fact that we can conceive of the concept
strongly implies that it's possible, and therefore there's a pretty high
probability that that's what our universe is.

------
max2grand
I'm still leaning towards you all just being a figment of my imagination. I'm
not crazy, but being the only being in the universe it's understandable that I
would have imaginary friends.

------
toemetoch
I'd say it's not a simulation but a crappy, cheap emulation. Lack of FTL, 'nuf
said.

------
c16
If so, let's hope no one hits ctrl + c.

~~~
Aqueous
Who cares? If someone hits control-C then our process is killed immediately
and we were none the wiser that we ever existed. Of course, if our process has
shut down hooks it would give us time to think about what's happening, which
might suck.

I would rather someone 'kill -9'ed us instead of using Control-C.

~~~
Apocryphon
Like if we were turned into a zombie process?

------
Ty2Runr
I dont't think so, but my avatar does.

------
omarchowdhury
Mind of God.

------
planetguy
It seems rather ontologically extravagant. I think they're vastly
underestimating the amount of computing power it would take to seamlessly
simulate a universe.

Still, there's one way to test the simulation hypothesis: build our own
planet-sized universe-simulating computer and see if our own universe has a
segfault.

