Loading ...
Sorry, an error occurred while loading the content.

What if Reality Was Really Just Sim Universe?

Expand Messages
  • medit8ionsociety
    Physicists propose experiment to test hypothesis that reality is just a computer simulation. Originally published: Dec 14 2012 - 5:00pm By: Joel N. Shurkin,
    Message 1 of 1 , Jan 3, 2013
    View Source
    • 0 Attachment
      Physicists propose experiment to test hypothesis that
      reality is just a computer simulation.
      Originally published:
      Dec 14 2012 - 5:00pm
      By:
      Joel N. Shurkin, ISNS Contributor
      http://www.insidescience.org/content/what-if-reality-was-really-just-sim-universe/871

      (ISNS) -- What if everything -- all of us, the world,
      the universe -- was not real? What if everything we are,
      know and do was really just someone's computer simulation?

      The notion that our reality was some kid on a couch in the
      far future playing with a computer game like a gigantic Sim
      City, or Civilization, and we are his characters, isn't new.
      But a group of physicists now thinks they know of a way to
      test the concept. Three of them propose to test reality by
      simulating the simulators.

      Martin Savage, professor of physics at the University of
      Washington, Zohreh Davoudi, one of his graduate students,
      and Silas Beane of the University of New Hampshire, would
      like to see whether they can find traces of simulation in
      cosmic rays. The work was uploaded in arXiv, an online
      archive for drafts of academic research papers.

      The notion that reality is something other than we think it
      is goes far back in philosophy, including Plato and his
      Parable of the Cave, which claimed reality was merely shadows
      of real objects on a cave wall. Sixteenth-century philosopher-mathematician René Descartes thought he proved reality with
      his famous "I think, therefore, I am," which proposed that
      he was real and his thoughts had a reality.

      Then, in 2003, a British philosopher, Nick Bostrom of the
      University of Oxford, published a paper that had the philosophy
      and computer science departments buzzing.

      Bostrom suggested three possibilities: "The chances that a
      species at our current level of development can avoid going
      extinct before becoming technologically mature is negligibly
      small," "almost no technologically mature civilizations are interested in running computer simulations of minds like ours,"
      or we are "almost certainly" a simulation.

      All three could be equally possible, he wrote, but if the
      first two are false, the third must be true. "There will
      be an astronomically huge number of simulated minds like ours," Bostrom wrote.

      His suggestion was that our descendants, far in the future,
      would have the computer capacity to run simulations that
      complex, and that there might be millions of simulations,
      and millions of virtual universes with billions of simulated
      brains in them.

      Bostrom's paper came out four years after the popular film,
      "The Matrix," in which humans discover they were simulations
      run by malevolent machines. The popularity of the film possibly contributed to the attention to Bostrom's paper received at
      the time, but nothing came of it.

      "He put it together in clear terms and came out with probabilities
      of what is likely and what is not," Savage said. "He crystallized
      it, at least in my mind."

      In the movie and in Savage's proposal, the discovery that
      reality was virtual came when unexpected errors showed up
      in life, demonstrating imperfections in the simulation.

      Savage and his colleagues assume that any future simulators
      would use some of the same techniques current scientists use
      to run simulations, with the same constraints. The future
      simulators, Savage indicated, would map their universe on a mathematical lattice or grid, consisting of points and lines.
      This would not be an everyday grid but a "hypercube" consisting
      of four dimensions, three for space, and one to represent points
      in time.

      A present-day example is lattice quantum chromodynamics,
      which explores the effects of the strong nuclear force, one
      of the four fundamental forces in the universe, on tiny
      elementary particles such as quarks and gluons. In this approach,
      the particles jump from point to point on a grid, without
      passing through the space between them. The simulations cause
      time to pass in a similar way, like the frames of film passing through a movie camera, so that the time that passed between
      frames is not part of the simulation. This style of simulation requires less computer power than treating space and time as a continuum.

      Because Savage and his colleague assume that future simulators
      will use a similar approach, he suggests looking at the behavior
      of very high-energy cosmic ray particles to see whether there
      is a grid in the energy as a start.

      "You look at the very highest energy cosmic rays and look for distributions that have symmetry problems, which are not
      isotropic," or the same in every direction, he said.

      "Everything looks like it is on a continuum," Savage said.
      "There is no evidence to show that is not the case at the moment."

      "We are looking for something to indicate you don't have a
      space-time continuum."

      That disturbance in the force might be a hint that something in reality is amiss. If the cosmic ray energy levels travel along
      the grid, like following streets in Manhattan or Salt Lake City,
      it probably is unlikely to be a simulation; if they unexpectedly travel diagonally, reality may be a computer program.

      Jim Kakalios, a physics professor at the University of Minnesota
      who was not involved in the paper, said a test such as the one
      Savage suggests may not prove anything. If they don't find the signatures, it doesn't mean we are not a simulation; our
      descendants could have used a different grid. If they do
      find something it also could mean "that's the way space-time
      is and we never noticed before," he said.

      Two other questions arise. One is whether it is conceivable
      that computers powerful enough to simulate our hugely complex universe ever will exist. If so, it likely will be very far in
      the future.

      The second question is linked: Will it ever be possible to
      simulate human consciousness? After all, we run around thinking
      and feeling.

      "Ultimately, the paper glides over the most interesting point:
      assume we have infinite computing power and we can create this hypercube," Kakalios said. "They assume [the simulators] would
      know how to simulate human consciousness."

      We are aware of ourselves, he said, aware of our bodies, aware
      of what is outside of our bodies, he said. Human consciousness
      is almost indescribably complex.

      For generations, science fiction books -- and some science books -- have hypothesized inserting our consciousness into computers so
      that we essentially live forever. In Caprica, a prequel to the television program Battlestar Galactica, a girl's consciousness
      is preserved in a computer and it becomes the basis for the evil cyborgs.

      "We don't understand consciousness," Kakalios said. "Neuroscience
      is where physics was before quantum mechanics."

      "It's a more interesting problem than whether you can simulate protons and quarks."

      Either way, however, Kakalios said the experiments on cosmic rays
      are the kind scientists should be doing regardless of the
      simulation issue.

      ________________________________________
      Joel Shurkin is a freelance writer based in Baltimore.
      He is the author of nine books on science and the history
      of science, and has taught science journalism at Stanford
      University, UC Santa Cruz and the University of Alaska Fairbanks.
      --------------------------------------------------------------------
      Fair Use Notice: This document may contain
      copyrighted material whose use has not been specifically
      authorized by the copyright owners. I believe that
      this not-for-profit, educational use on the Web
      constitutes a fair use of the copyrighted material
      (as provided for in section 107 of the US Copyright Law).
      If you wish to use this copyrighted material for purposes
      of your own that go beyond fair use, you must obtain
      permission from the copyright owner.
    Your message has been successfully submitted and would be delivered to recipients shortly.