- 20 April 2009 by Marcus Chown
- Magazine issue 2704. Subscribe and get 4 free issues.
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GREAT news, there may be a way to avoid a looming disaster. All you need to do is forget all about it by "resetting" your memory.
That's the claim of physicist Saibal Mitra at the University of Amsterdam in the Netherlands, and it is predicated on the existence of parallel universes.
The "many worlds" concept is an interpretation of quantum theory - our best description of the microscopic world of atoms and their constituents. Many worlds takes literally quantum theory's idea that a quantum entity like an atom can exist in many states at once, and posits the existence of parallel universes containing infinite copies of you with different histories and futures.
Imagine that on learning of an impending disaster - perhaps a catastrophic asteroid strike on its planet - the machine resets its memory. Now, an observer sat next to the machine can verify that the "same machine" will still face disaster after the reset. But from the perspective of the machine's reset memory, the state of the universe in the many-worlds scenario becomes "undetermined". After all, for all the machine knows, the reset probably occurred for a mundane reason, such as a crash of its operating system.
The next part defies our natural instincts: according to the many-worlds interpretation, all of these undetermined possibilities actually exist and open up to the machine. Even though it followed one particular history up to its resetting, it can be dealt a new card, says Mitra. So, from its unwitting perspective, the machine could "switch" to a parallel universe. The probability of a memory reset due to a rare event like an asteroid strike would be far smaller than the probability of a routine reset due to a glitch, and so there will be many more universes in which the disaster does not occur. "Consequently, the machine will almost certainly find itself in one of these universes and avoid the catastrophe," says Mitra (http://arxiv.org/abs/0902.3825)
"If we could find a way to reset our knowledge of an impending disaster, we too could avoid it," he says. The downside of such memory resets, however, is that there is a small chance you will "wake up" in a universe facing an even more cataclysmic disaster than the one you were trying to dodge. "You'd have to weigh up whether it would be worth the risk," Mitra concedes. Read the rest here
Now, people. I know I'm opinionated and curmudgeonly but - really:
Even if he happens to be correct - which I doubt, it still leaves me with "other dimension" versions of myself which suffer all possible catastrophes and corresponding painful forms of injury or demise.
Each instant of existence would - in that view generate a multitude of branching universes in some of which the world is destroyed, in some of which the world is only seriously injured and in some of which the world escapes serious injury.
Every action a person takes (or does not take) would, perforce, generate a branching of reality - and this multiplied by all the billions of humans now living (or who have ever lived) - leaving us with literally uncountable billions (or a couple of orders of magnitude beyond) of co-existent realities which we would not be able to discern in any fashion as each would form a separate universe from its branch point.
I have read some science-fiction stories which use this device as a factor in the plotting and it makes for pretty interesting reading - but to believe it is actually so and can be an alternative to global damage caused by man or star is beyond madness as all that is offered is a possibility that the particular branch of reality that you are conscious of will avoid the catastrophe which leaves multitudes of less fortunate outcomes in which other "yous" will suffer every possible outcome of the event.
And then there is the sheer physical issue: IF (big if) every possible outcome of every possible situation happens simultaneously, what is the membrane which conceals from us the myriad exploding stars and colliding planets which did not happen in our version of reality?
Where lies the sorry Earth on which the Third Reich was triumphant in 1944 and repelled the allied invasion? Where is the Earth on which King George's armies swept the field of Washington's little army? Where is the Earth on which the USSR still lives and holds sway over the people of the world? Where is the world on which Captain Cook was not killed for being stupid in Hawaii? Where is the world on which the native Americans were not susceptible to European diseases and repelled invasion by the contemptible little bands of colonizers? Where is the world where the African people effectively resisted European and Arab slavers?
I'd like to see the math that explains the separation of all those possible outcomes of every decision point effecting each and every moment of the existence of the universe. I'd like to see a cogent explanation of the physical means of separation of each "separate universe" or "divergent reality" created in that fashion - wouldn't you?