### Aaronson on the Nature of Quantum Mechanics

#### Posted by Urs Schreiber

Scott Aaronson is a remarkable thinker and expositor, as you can convince yourself of for instance by following his blog.

He is among the few who managed to pull off something of genuine intellectual interest from a meme that is currently haunting the high energy physics community, known as the “anthropic principle”.

If you want to see a lot of confusion among smart people, google for the “anthropic principle”. Then go back and read this piece by Scott Aaronson to see the difference.

And if you happen to have followed the stringy part of the blogosphere in the last months and are in need of some great entertainment, you should not miss the blog entry accompanying this.

But I am writing this here not to talk about the anthropic principle, but about quantum mechanics.

On this blog here, we enjoy, from time to time, to muse about the nature of quantum mechanics in the light of general abstract nonsense. Lately for instance in the entry Common Applications and also in the discussion starting here.

Scott Aaronson is a complexity theorist, thinking about quantum computation. Accordingly, he has his views on the nature of quantum mechanics. In his latest transcript of a lecture he is giving, he explains to his students why there are various reasons that we should *not* be surprised about the nature of quantum mechanics. An intellectual treat. Even - and maybe especially - for the layman.

In essence, he explains that *if* we are going to consider any generalization of ordinary classical probability theory, then quantum probability is the most natural of all alternatives.

Personally, I believe that if we are ever going to *really* understand “Why quantum mechanics?”, it will involve considerations considerably beyond what Scott Aaronson mentions there, namely such more along the lines of John’s Quantum Quandaries. But he certainly mentions some noteworthy points.

Among them, somewhat vague but intriguing, is a relation to Fermat’s last theorem that he points out.

But the most powerful insight he mentions is probably that nonlinear deformations of quantum mechanics would allow to solve NP problems in polynomial time.

In order to appreciate this, you may want to read Aaronson’s Reasons to Believe.

P.S.

John mentioned many related things in TWF 235.

Posted at January 16, 2007 2:13 PM UTC
## Re: Aaronson on the Nature of Quantum Mechanics

Aaronson’s piece was certainly the most intelligent and enlightened thing I’ve read about the anthropic principle in a long time. It actually made me smile and ponder, which I don’t think I had done in this context since I had read Carl Sagan’s words on the subject:

This comes from

Pale Blue Dot(1994), for the curious.I think it also relates to the brain-teaser I heard from David Brin at ICCS 2006, namely that it’s a thousand times more likely that we’re living in a simulation than in the real world (because the post-Singularity folks can run a thousand simulations at will), but I haven’t had enough caffeine this morning to figure out exactly how.