Cosmos is crude computer model made by our descendents

[Eddiesilence]

A news story about this paper has been posted before, but I wanted to draw attention to the actual paper, (PDF at the link below). Has anyone here sufficient maths to translate the finer points, so I can get a better idea of how persuasive it is?

Constraints on the Universe as a Numerical Simulation

Silas R. Beane,1, 2, # Zohreh Davoudi,3, y and Martin J. Savage3,

Institute for Nuclear Theory, Box 351550, Seattle, WA 98195-1550, USA

Helmholtz-Institut für Strahlen- und Kernphysik (Theorie),

Universität Bonn, D-53115 Bonn, Germany

Department of Physics, University of Washington,

Box 351560, Seattle, WA 98195, USA

Dated: October 9, 2012 – 0:14

Abstract

Observable consequences of the hypothesis that the observed universe is a numerical simulation performed on a cubic space-time lattice or grid are explored. The simulation scenario is first motivated by extrapolating current trends in computational resource requirements for lattice QCD into the future. Using the historical development of lattice gauge theory technology as a guide, we assume that our universe is an early numerical simulation with unimproved Wilson fermion discretization and investigate potentially-observable consequences. Among the observables that are considered are...

1. Introduction

Extrapolations to the distant futurity of trends in the growth of high performance computing (HPC) have led philosophers to question —in a logically compelling way— whether the universe that we currently inhabit is a numerical simulation performed by our distant descendants [1]. With the current developments in HPC and in algorithms it is now possible to simulate Quantum Chromodynamics (QCD), the fundamental force in nature that gives rise to the strong nuclear force among protons and neutrons, and to nuclei and their interactions.

arxiv.org/pdf/1210.1847v1.pdf

[Hughie Green]

42

[slartibartfast]

[wildbill]

Can't be that bad surely? The Greeks used a slide rule :wink:

Silas R. Beane would be a good alias

[Flobalobalobalot]

. .Silas R. Beane, Zohreh Davoudi and Martin J. Savage .

.. reading from Douglas Adams thirty five year old idea. .

[Eddiesilence]

. .Silas R. Beane, Zohreh Davoudi and Martin J. Savage .

.. reading from Douglas Adams thirty five year old idea. .

The theory is basically "Horton Hears a Who" by Dr Seuss, from 1954.

[strawberry]

A news story about this paper has been posted before, but I wanted to draw attention to the actual paper, (PDF at the link below). Has anyone here sufficient maths to translate the finer points, so I can get a better idea of how persuasive it is?

Beane et al, suggest that they can experimentally determine if we are part of a simulation. Whether they do that or not is an issue of philosophy, and not physics. The background to the philosophical argument is here: Extract from The Ladybird Book of Posthumanism

What they have done is firstly explain a technique for modelling the universe which may be possible given future computing power, and secondly list a few methods for checking the success of the model.

There is a parallel with analogue vs digital audio. An audio signal is sampled at a fixed rate, and that rate dictates the maximum frequency which can be recorded (in simple terms, the max freq is half the sampling rate, so for example a CD recorded at 44,100 samples per second can record frequencies up to 22.05kHz). If no sound existed in our universe above 22.05kHz, all audio could be entirely modelled with the 44,100s^-1 sampling rate, such that there would be no effective difference between 'real' sound and a computer simulation.

Rather than digitising audio, Beane's models use discretisation to render a modified form of the space-time continuum in a lattace form. Rather than discussing maxium frequencies and sampling rates, they discuss maxium energies of particular particles and their connection to the distance between nodes in the lattace. There are other issues that relate to the multiple dimensions used in the model. But, in effect they argue that their techniques could entirely model all observations....

I don't think, therefore I cannot comment on the philosophical argument.

[Boojum]

I don't think, therefore I cannot comment on the philosophical argument.

It's Descartes for the computer age, innit.

[Mephitis]

A news story about this paper has been posted before, but I wanted to draw attention to the actual paper, (PDF at the link below). Has anyone here sufficient maths to translate the finer points, so I can get a better idea of how persuasive it is?

Beane et al, suggest that they can experimentally determine if we are part of a simulation. Whether they do that or not is an issue of philosophy, and not physics. The background to the philosophical argument is here: Extract from The Ladybird Book of Posthumanism

What they have done is firstly explain a technique for modelling the universe which may be possible given future computing power, and secondly list a few methods for checking the success of the model.

There is a parallel with analogue vs digital audio. An audio signal is sampled at a fixed rate, and that rate dictates the maximum frequency which can be recorded (in simple terms, the max freq is half the sampling rate, so for example a CD recorded at 44,100 samples per second can record frequencies up to 22.05kHz). If no sound existed in our universe above 22.05kHz, all audio could be entirely modelled with the 44,100s^-1 sampling rate, such that there would be no effective difference between 'real' sound and a computer simulation.

Rather than digitising audio, Beane's models use discretisation to render a modified form of the space-time continuum in a lattace form. Rather than discussing maxium frequencies and sampling rates, they discuss maxium energies of particular particles and their connection to the distance between nodes in the lattace. There are other issues that relate to the multiple dimensions used in the model. But, in effect they argue that their techniques could entirely model all observations....

I don't think, therefore I cannot comment on the philosophical argument.

[strawberry]

I still can't think of Descartes without bloody Jim Davidson popping up in my mind. As twisted as I am, there is no way my mind conceived him....

[Boojum]

Plus Descartes was a pig thick, unfunny, racist, misogynistic, wife beating homophobe.

OK, I made that up.

Edited October 25, 2012 by Boojum