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Comment by w_for_wumbo | Hacker News Reader

Especially if each frame of the simulation derives from the previous one. How do you think this universe works, to me that sounds exactly the same. Every moment is derived from the previous instant.

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Leaving aside the question of whether the universe is discrete or continuous, a simulation would still have lower "resolution" than the real world, and some information can be lost with each time step. To compensate for this, it can be helpful to have simulation step t+1 depend on both the step t and step t-1 states, even if this dependency seems "unphysical."

The universe evolves exactly under physical laws, but simulations only approximate those laws with limited data and finite precision. Each new frame builds on the last step’s slightly imperfect numbers, so errors can compound. Imagine trying to predict wind speeds with thermometers in the ocean — you can’t possibly measure every atom of water, so your starting picture is incomplete. As you advance the model forward in time, those small gaps and inaccuracies grow. That’s why “finer detail” from a coarse model usually isn’t new information, just interpolation or amplified noise.

> The universe evolves exactly under physical laws

Has this been confirmed already? Seems like the 'laws' we know are just an approximation of reality. 2) if none external intervention has been detected it doesn't mean there was none.

Fine details. We are talking about NN model vs algorithm. Both are approximation, and in practice model can fill the gaps in data that algorithm cannon, or does not by default. Good example would be image scaling with in-painting for scratches and damaged parts.

There are no frames in the real world, it literally does not work like that.

There are frames in simulations though! Typically measured as time steps. That the frame usually has N_d dimensions is insignificant.

There are frames in every digital signal. Like a simulation.

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