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Comment by dbz | Hacker News Reader

I didn't read the entire thing, but I got far enough to do this:

We all know the grandfather paradox: http://en.wikipedia.org/wiki/Grandfather_paradox

Go back in time and kill your grandfather- wait that doesn't make sense? You wouldn't be alive?

I now introduce the Dbz Paradox:

Know the future and then change it before it happens- wait that doesn't make sense? I'm not sure about the consequences to this one.

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> I didn't read the entire thing.

It has nothing to do with time travel, if you didn't care to read the article, why care to comment.

Also you can probably only know the future of different, possible similar timelines. Whatever changes you make in those other timelines will not affect your own. You can alter their future but not your own, otherwise you can alter causality. I don't know if altering causality makes any sense.

A perfect deterministic world simulator will imply the ability to see into the future, which would give rise to the "Dbz Paradox", even if that was not the point of the story.

It is not exactly a new revelation, if you include a model in the model, the problem potentially arise. What you typically do is to keep running the model with the previous answer, and hope the answer converge. It is a common technique for finding numeric solution to the more complex equation systems. I have done it many times. Of course, there is in general no guarantee that there is a solution, that the solution is unique, or that you will find it using this technique.

But if the simulated worlds are deterministic as implied then you could run the simulation forward into the future if your reality also followed the same determinism. Doing this would cause an interesting paradox where knowledge of the simulated future could change what you do in the real world. For example, simulate forward to the next lottery drawing to discover the numbers. Then play those numbers in the real world and win the lottery.

This all depends on the fact that the simulation and the real world are deterministic which, it would seem, is highly improbable.

In the context of this story, the simulation below you would also be looking into the future, and the simulation above would be looking at your future. Whatever "future" is seen has to be reflected in every simulation.

This doesn't change much, the problem irons its self out. I see no paradox. And I don't know what you see that makes determinism "seem improbable."

For the sake of argument, let's say that world zero (W0 for short) is at some arbitrary level. Worlds being simulated below that level would be -W1, -W2, etc. Worlds above would be W1, W2, etc. If everything is deterministic then worlds at all levels take the same path and arrive at the same outcome. But if W0 has control over the -W1 timeline, then W0 can view it's own future by moving the -W1 timeline forward. W0 now knows it's own future (lottery numbers for arguments sake). W0 can now use that knowledge to change it's future. The W0 future is now different from the W1 future which contradicts the ability for all worlds to be deterministic.

As I said, every simulation within the context of this story would be looking into the future via the lower simulation.

In this argument, every simulation would look into the future to see the lottery numbers, and would act out on this knowledge. There would be no "changing the future." Every simulation would see the lottery numbers, then see themselves go to the store and get a ticket with the numbers, and every simulation will win with those numbers. There was no other future. The future you see in the simulation is the future that will occur in your own simulation.

Calling this a paradox is like calling recursive mirrors a paradox.

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