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Is the Universe its own Largest Computer?
missingmatterboy writes: "If the universe is simply a giant calculating machine, how big is it? Seth Lloyd, who two years ago worked out the theoretical maximum possible power a laptop computer could posess, has now "estimated how much information the Universe can contain, and how many calculations it has performed since the Big Bang." His conclusion: you'd need about 10^90 bits, with something like 10^120 manipulations of those bits, to express the universe since time began."
If one plans on estimating the calculations (apparently changes) the universe has performed, how can you even make a guess when we still don't even know precisely how old the universe is, and how much matter there is?
And also, why does everything have to be made into a computer of some sort? DNA, and now the whole universe?
WWJD.... for a Klondike bar?
Then again, I'm hardly a cosmologist, so YMMV.
Mike
And also, why does everything have to be made into a computer of some sort?
Maybe because its so much easier to think about God as a fellow programmer?
If programs would be read like poetry, most programmers would be Vogons.
I guess 256 bits of encryption (where each possible combination results in a strong key) will never be brute-forced, then.
Oceania has always been at war with Eastasia.
Isn't the Universe an analog sytstem?
It's nice that he decided that changes in quantum state are equivilent to 'bits', the changes in the universe also happen without a quantum state change. He also doesn't acount for the movement of sub-atomic particles, or even the number of quantum states of each paricle. These 'bits' in his formula could not be binary for sure.
Hence it seems to me his equation is flawed in attempting to express the universe as a digital computer. Perhaps he should re-state the problem and look at the universe as an analog computer like it really is.
Article X: The powers not delegated... by the Constitution...are reserved...to the people
Nobody has mentioned yet this little nugget: If the universe is a computer then we are but small little threads of the Earth process. And we have no such thing as free will... just private member variables that we're not aware of.
--Rob
I've thought about this before, and came to the conclusion that if I ever build my own universe I'm going to need to use data compression of some sort, and kind of fudge the details. I mean, who cares exactly where an electron is, as long as it statistically behaves like it should?
The scary thing is, the more I've learned about quantum mechanics, the more it looks like that's how the universe works.
Making one a small sim-universe system wouldn't add to the total number of operations in the universe. Since the total number was calculated based on the total amount of mass in the universe and since your computer would be made from a portion of that same mass, those calculations are already being counted.
- learn mathematics - shoot dope -
Between lesson 2 and lesson 3 you've botched things. Just because the particle has a wavefunction over an infinite domain does not mean it contains an infinite amount of information.
If the particle has finite energy, then that places a limit on the curvature of the wavefunction, and therefore on the "information density" of that wavefunction.
Furthermore, the finite age of the universe sets a limit on the distinguishability of particle states from one another. Very fine separation of energy states require a long evolution period to be distinguishable. (delta-E delta-t ~ h-bar) That sets a limit on the number of currently distinguishable eigenstates of the universe.
It's not an analogy. It's a perspective. From a certain point of view the universe might look exactly like a computer. If it does then it might as well be a computer because you can treat it exactly like one. This doesn't preclude the possibility that there might be other points of view too.
There is, of course, the possibility that it's not a valid point of view. But that needs more arguing than simply "the universe isn't a computer".
-- SIGFPE
no, I am saying that since the computer would be in the universe, it can never simulate everything in the universe, because it is IN the universe itself. You need more matter, energy or time to simulate something then the matter/energy/time it took to do the thing in the first place.
How can you simulate 5 atoms using only 2 atoms? answer, you can't. You would need AT LEAST 5 atoms. Take this argument to the next level and you would need AT LEAST every atom in the universe, to simulate the universe. And that doesn't take into account overhead, which I am sure would be quite large.
Just look at where we are today, it takes a year for a supercomputer the size of a football stadium to simulate a few hundred atoms for a couple microseconds.
The only way I can see anything simulating the universe is if they find a way to tap into a quantum effect to use multiple universes to simulate our universe (assuming there are multiple universes).
Just wait for the next generation of computers then: they will be able to simulate the whole history of the universe, plus those 600 years, plus another 13 *billion* years more :).