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Re:WiFi: “beamforming” only begins to describe it (2014) by ampdepolymerase on Sunday April 05, 2020 @08:41AM (#22785299)
You are still not cheating entropy with that.
Re:WiFi: “beamforming” only begins to describe it (2014) by namibj on Sunday April 05, 2020 @09:22AM (#22785440)
I didn't claim it did.

But you get diminishing returns from around 1bit/s/Hz if you just turn up the power. Your energy efficiency will go down, a lot. The more you can get spatial multiplexing to keep you away from that border, the less energy you'd need to dump into the air. And as computing get's cheaper, that energy tradeoff moves more and more towards MIMO. Back in 2005 we didn't have a need to think of 8x8 MIMO (Laptop <=> AP). Now it becomes realistic, so we got it specified and standardized in 802.11ac to allow everyone to join in the testing/experimental setups.

Re:WiFi: “beamforming” only begins to describe it (2014) by LegitShady on Sunday April 05, 2020 @09:17AM (#22785427)
I think when we come up with a way to cheat entropy it will be bigger news than wifi.
Re:WiFi: “beamforming” only begins to describe it (2014) by derefr on Sunday April 05, 2020 @11:15AM (#22786031)
As an aspiring speculative-fiction author always on the hunt for a new premise, I’d love to know, what would be possible if we could “cheat entropy” in this sense?

(This doesn’t have to be possible in our universe; posit a universe where it is possible—maybe one inside a Matrix-like simulation inside our own universe, if you like.)

Re:WiFi: “beamforming” only begins to describe it (2014) by Filligree on Sunday April 05, 2020 @11:25AM (#22786106)
So many things would break.

The statement that we cannot cheat entropy is basically a statement that the volume of an evolving quantum system (in phase space) stays constant over time, but gets more complex.

Entropy increases because our maps of that volume increase in volume, because we can't follow all the little eddies and crinulations.

So, okay. Two options for you: Maybe we can follow it, because the universe turns out to be more predictable than expected. This is basically a statement that chaos theory is wrong, and entropy isn't increasing as fast as our current understanding of the rules say.

Alternately, maybe the volume of the actual phase space is decreasing over time. This would allow the volume of our estimates to stay constant despite increasing complexity, but breaks linearity and suggests the universe might be going away.

Re:WiFi: “beamforming” only begins to describe it (2014) by willis936 on Sunday April 05, 2020 @12:41PM (#22786592)
While information theory entropy and physical entropy are not identical concepts, they are coupled. I recommend Isaac Asmiov’s “The Last Question” if you haven’t read it already.
Re:WiFi: “beamforming” only begins to describe it (2014) by ampdepolymerase on Sunday April 05, 2020 @01:01PM (#22786737)
There are processes that decrease local entropy but increase global entropy. We call it life.