How plausible is a computer simulation of the laws of the universe as we know them today?

redcardoor56: How plausible is a computer simulation of the laws of the universe as we know them today?
With what humankind knows today of the laws of physics, is it possible or plausible to create a virtual universe that obeys the same laws we do? How great of an effect would you speculate the unknown laws have on the universe? When it comes to a functional model, how important are the little things? Could the laws be practically entered into a computer simulation that replicated our universe?

Answers and Views:

Answer by nshooter11
There is no reason that this could not be achieved by someone with sufficient physics and programing knowledge. Of course, the simulation would only be as good as the information put into it – by error-ridden humans…

Answer by ?
If you dont know the begining of the simulation the entire thing is flawed. All we know today is how wrong we were yesterday.

Answer by Ramaseese
At the moment it is impossible to replicate the universe using a computer. Industrial light and magic can do a pretty good simulation, however that is Hollywood fiction.
How could a computer programmer program dark matter for instance. Among millions of other unanswered questions.
Don’t forget even the big bang is based on theory.

Answer by vorenhutz
computers today are powerful, but nowhere near that powerful. just about every computer simulation makes approximations of one kind or another to speed up the calculation. of course one always attempts to verify that the approximations are justified, either by running a more detailed model on a smaller system and comparing (exact) theoretical results with (approximate) theoretical results, or by simulating a situation for which the experiment has already been done, and comparing the experimental results with the theoretical results. there are hardly any situations where all the natural forces are relevant at the same scale – when determining the structure of molecules for instance, you can completely ignore gravity because it’s so much weaker than the other forces. weather simulations can’t possibly consider atoms – there are way way too many atoms to keep track of them all, the basic elements of those simulations are blocks of air perhaps hundreds of meters on a side. that limits the accuracy of the simulation but it would be hard to get data more accurate than that to feed into the simulation anyway.

hope that helps.

Answer by jondalar469
This sort of thing is done for “special cases” already. For example, my celestial mechanics programs sometimes use a time-step evolution procedure to check a Keplerian transfer orbit whose elements were output at an earlier stage of the program. That’s an example of computer simulating certain laws of the universe. Now, you probably had a more comprehensive model in mind, one in which life could evolve and then maybe intelligent virtual life that could invent philosophical ideas that nobody ever had before, and you’d play God over them, and, on the side, you’d get rich selling their inventions (which you’d patent as your own) and try to persuade lawmakers to impose their social ideas on us Real Folks.

Answer by Clavius
Not plausible at all.

While we know much about the nature of the universe, we do not formulate it as a self-consistent, complete set of constitutive relationships, nor likely can we. That is the first step to presenting it as a computer algorithm.

As is mentioned, visual-effects houses do very well to simulate the appearance of portions of the universe, but not all their methods are physically-based. That is, not all the simulated effects of light are achieved by modeling the true behavior of light; and not all motion is achieved by replicating the laws of kinetics and gravity. To achieve those pictures, many “hacks” are employed that reduce the computing time and produce results similar to what we observe, but without modeling the underlying laws.

With supercomputers employing thousands of processors, terabytes of memory (a terabyte is a 1,024 gigabytes) and lots of patient programming, we can simulate portions of the behavior of the universe, such as the way a car body crumples in a collision, or how heat is transferred through a building structure during a fire. These take a long time to compute and don’t happen in “real time.” And they model only a portion of the laws of nature.