Simulation Hypothesis and Simulation Technology
Evgenii Rudnyi
technology falls short of the simulation hypothesis at
http://blog.rudnyi.ru/2011/09/simulation-hypothesis-and-simulation-technology.html
It could be considered as some small empiric case study.
Evgenii
meekerdb
My practical experience with simulation has often been disappointing. It works best when
abstracting out a relatively small number of relations and simple physics. But on the
other hand, what can be simulated has vastly expanded over the 50yrs of my career. So
when this or that ambitious project fails I don't conclude that the trend is stopped.
Brent
Evgenii Rudnyi
Modern simulation software is actually not that bad. If one keeps things
simple, then the chances to get the right answer for the first time are
quite high even for a design engineer. I mean that default settings and
default meshing are working reasonably well. This is one of the reasons
that the simulation business grows extraordinary well: design engineers
can solve for example a linear structural mechanics problems by
themselves, the bachelor level suffices.
The problem in the real world however is not just simulate at any cost
but rather to earn money. The IBM case is interesting exactly from such
a pragmatic viewpoint. If the business does not bet anymore on monstrous
supercomputers, then it is an interesting sign.
When I talk to engineers working on electromobility, I mention that
theoretically one could think of simulating the whole hybrid vehicle at
once (structural mechanics, heat transfer, CFD, electromagnetics in a
single simulation) - they like it. Yet, they do not bet on that, they
are pragmatic.
Evgenii
meekerdb
Of course part of the reason they don't bet on that is that they understand the vehicle
pretty well and so they are confident that the CFD won't interact with the instrument
panel lights and the suspension won't interact in some unforseen way the the engine.
However, if they were designing a robotic rover to investigate the surface of Titan for
example then they would be much more interested more comprehensive simulations.
Just last year I wrote a heat transfer simulation for a vehicle and I got different
answers from the manufacturers simulation. It was because he had neglected the fact that
accelerations change the internal convective heat transfer.
Brent
Stathis Papaioannou
To say that simulating a system effectively is difficult, or even
computationally intractable, does not amount to a philosophical point
about the computability of the universe. A Turing Machine has
unlimited resources.
--
Stathis Papaioannou
Evgenii Rudnyi
Then your statement is of a philosophical nature and has nothing to do
directly with empirical studies.
Evgenii
Evgenii Rudnyi
This is one of the reasons why CFD is popular nowadays. Yet, modeling of
boundary layers is still a tricky business. The default settings for
meshing are working but not all the time.
In general, industry is definitely interested in more comprehensive
simulations. The question is however how to reach such a goal and how
much it will cost. Say electronics now is a part of a product and it
must be simulated as electronics, then thermal, EMC, durability (it must
work 10 years), etc. A typical simulation scale (substitution level)
starts from nanometers on a chip and then it goes to decimeters at the
whole system. This is why engineers are not afraid of AI and simulation
hypothesis.
Evgenii
Stathis Papaioannou
>> To say that simulating a system effectively is difficult, or even
>> computationally intractable, does not amount to a philosophical
>> point about the computability of the universe. A Turing Machine has
>> unlimited resources.
>>
>
> Then your statement is of a philosophical nature and has nothing to do
> directly with empirical studies.
Yes.
--
Stathis Papaioannou