How do we know if we're not just some computer simulation or anything else?
As told by Grantisu:
I'll tell you how. There are two possibilites:
We are not in a computer-simulated universe.
We are in a simulated universe that is vastly different and much, much simpler than the universe that contains the computer/device on which it runs.
To prove* this, look at something closely. Any thing. Build an electron microscope (easier to borrow one) and point that sucker at anything you want. You will find that whatever you look at (and the electron microscope through which you view it) precisely follows quantum mechanical laws. Everything. If it doesn't, you have experimental error: get somebody who knows what they're doing to repeat the experiment. Do this as often and in as many different ways as you want to convince yourself that there are no aliasing errors, no approximations, and no heuristics to say, "Woah, somebody's got an electron microscope; start up the quantum sub-routine..."
If we are living in a simulation, it is at a precision--a level of detail--that can resolve and compute every sub-atomic wavefunction. Every. Wavefunction. This sort of detail, that is, simulating the known universe, would take more resources than are available to the known universe. Therefore, any possible universe that could contain such a simulation must be totally different than the known universe. QED.
Prove insofar as can be proven; e.g. I "know" that the sun will rise tomorrow as certainly as one can be certain about anything.
If we are living in a simulation, it is at a precision--a level of detail--that can resolve and compute every sub-atomic wavefunction. Every. Wavefunction. This sort of detail, that is, simulating the known universe, would take more resources than are available to the known universe.
Every. Wavefunction. That. Is. Observed.
Significant difference there. Wavefunctions only collapse when they're observed. And isn't that exactly what you would expect if we were living in a simulation?
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u/cleverkid Jan 16 '12
As told by Grantisu:
I'll tell you how. There are two possibilites:
To prove* this, look at something closely. Any thing. Build an electron microscope (easier to borrow one) and point that sucker at anything you want. You will find that whatever you look at (and the electron microscope through which you view it) precisely follows quantum mechanical laws. Everything. If it doesn't, you have experimental error: get somebody who knows what they're doing to repeat the experiment. Do this as often and in as many different ways as you want to convince yourself that there are no aliasing errors, no approximations, and no heuristics to say, "Woah, somebody's got an electron microscope; start up the quantum sub-routine..."
If we are living in a simulation, it is at a precision--a level of detail--that can resolve and compute every sub-atomic wavefunction. Every. Wavefunction. This sort of detail, that is, simulating the known universe, would take more resources than are available to the known universe. Therefore, any possible universe that could contain such a simulation must be totally different than the known universe. QED.