Live data from Hacker News

It’s time to admit quantum theory has reached a dead end

nautil.us

181–190 of 236 posts

Re: It’s time to admit quantum theory has reached a dead end

#181
post #10

Maybe start connecting the structures in our brains with the structures in our math. The limited representational capacity of meat-based brains is probably constraining what can be understood. Even math may be too constrained to go beyond current level of detail. I imagine an AI doing its own experiments with the universe will have unbounded understanding, but i doubt we d be able to understand her when she tries to…

I'm surprised humans have gotten this far in understanding the rules of the universe and making accurate predictions. There's no evolutionary reason why we would have: our brains only hold like 7 ~ 11 things in working memory, we're almost always thinking about either food, entertainment, sleep, or sex, we can't conceptualize infinities, we're stuck living in linear time at 1 second per second, our long term memory i…

You may be on to something. Sure human working memory (insofar as our measurement tools can tell us) seems to be limited to single-digit datasets, and long-term (that is, persistent) memory is poorly understood but research portrays that it's a pile of more or less random bits.

It's a subject of professional interest to me for decades, what impresses me is how much isn't known about how our built-in "computer" actually works. Above all neurons are extraordinarily intricate structures, and beyond that the contributions of non-neurons in the brain appear to be considerable. Given that the brain contains at least 100's of millions of participating neurons organized in a complex hierarchical network, no wonder it's still not possible to adequately account for many relatively simple phenomena let alone the emergence of towering genius.

Indeed our wetware is collectively both more capable (and more limited) than we generally appreciate. Definitely we can't predict where genius will arise, it always seems to surprise when it happens. To say it's a miracle may be naive, but perhaps that just expresses wonder and gratitude for a rare, random and highly fortuitous event.

Re: It’s time to admit quantum theory has reached a dead end

#182
post #64

Amusing to see all the pessimistic comments form programmers who have zero understanding beyond high school maths thinking somehow there is a magic solution to all the problems in physics like you can just refactor everything. Quantum field theory is definitely not stuck in the 1920s. Modern physics has a lot more going on than 19th century mathematics. We understand quite a lot about the mathematical structure under…

While I do get what you're trying to say, it has to be said that many CS people have been exposed to Quantum Physics. Quantum computing is an elective at every half-decent University. To think that programmers have zero understanding beyond high school math is just ignorant.

I don’t disagree that computer science intuition isn’t interesting, or that CS people can’t contribute. There are plenty of deep connections all over the place. You can conjecture all you want. My issue is with the tone.

Re: It’s time to admit quantum theory has reached a dead end

#183

Earlier quoted context omitted.

I read somewhere that quantum mechanics is the most tested of all scientific theories. And it has been shown to be right, every time. Hawking espoused this idea he called “model dependent realism”. The idea is that every human understanding of reality is model-dependent, that is, it is not “reality” that we truly understand (we can’t) but rather in every case we have some model of reality that is useful in particular…

Apparently Hawking coined this term in 2010. Robert Anton Wilson coined a similar term, "Model Agnosticism", all the way back in 1977 in his book Cosmic Trigger: "The Copenhagen Interpretation is sometimes called "model agnosticism" and holds that any grid we use to organize our experience of the world is a model of the world and should not be confused with the world itself. Alfred Korzybski, the semanticist, tried t…

"All models are wrong, some are useful" describes it very well for me. It still amazes me, how late I really understood this and how many intelligent people not fully understand it.

Re: It’s time to admit quantum theory has reached a dead end

#184
post #170

I find it kinda hilarious that you all seen to be discussing some sort of cutting edge or controversial idea called "quantum theory" or "quantum physics", when I have to assume you're taking about century old theories of quantum mechanical systems like ones that continue to help design the electronics that you read this piece of shit article on.

Well yeah, there is still unresolved issue(s) with at the very least the interpretation of quantum theory, if not the math. Before decoherence things were even worse, and that was much less than a century ago. The fact that physicists still haven't reached a consensus on what the theory means is very intriguing to many people. Although it's true that people probably underestimate just how much this territory has been trodden. The current quantum computing hype likely plays a role in it seeming "cutting edge". It may just be flavour of the month.

Re: It’s time to admit quantum theory has reached a dead end

#185

As former amateur physicist, who read a couple books over the years :) To me it's quite simple. We haven't detected what is causing the waves that the particle of light is riding on. The particle of light is like a surf board, riding a wave and will always hit the shore in the interference pattern. Einstein and Bohr were both right. What has been the wrong assumption over the years is that the light is generating the…

Not saying you're wrong in the slightest, but why would our universe be like a computer? When our understanding of the universe was very primitive we thought everything was alive (animism). Then a little more technology and we thought the universe was like an orrery or a clock (mechanism)[0]. Then a little more and we think it was like a computer (turingism?) Occasionally you'll hear it's like a hologram, a simulatio…

> why would our universe be like a computer?

Because information is fundamental.

Computers just so happen to be our best tools in the information domain.

Re: It’s time to admit quantum theory has reached a dead end

#186

As former amateur physicist, who read a couple books over the years :) To me it's quite simple. We haven't detected what is causing the waves that the particle of light is riding on. The particle of light is like a surf board, riding a wave and will always hit the shore in the interference pattern. Einstein and Bohr were both right. What has been the wrong assumption over the years is that the light is generating the…

>All computers require a clock to function. Why would our universe be any different? Clocks are not required at all, even for digital computers. They only make designing computers a lot simpler.

Clockless computers don't have a global clock but they still have components that "tick".

Re: It’s time to admit quantum theory has reached a dead end

#187
post #73

As former quantum physicist, I find it little troubling to read "quantum theory has reached a dead end" in specific reference to the interpretation of quantum mechanics. Most quantum physicists could not care less about how quantum mechanics is interpreted when it makes highly accurate quantitative predictions, and there are still plenty of interesting open problems for quantum theory (e.g., related to the practical…

How can you be a "former quantum physicist"? Did you somehow unlearn everything that made you a quantum physicist? Maybe you meant to say "formerly paid to be a quantum physicist"? :-)

I guess "quantum physicist" can mean either an academic credential or a job title. In my case, I have the former but no longer the later. I finished my PhD nine years ago and no longer work in the field.

Re: It’s time to admit quantum theory has reached a dead end

#188

As former amateur physicist, who read a couple books over the years :) To me it's quite simple. We haven't detected what is causing the waves that the particle of light is riding on. The particle of light is like a surf board, riding a wave and will always hit the shore in the interference pattern. Einstein and Bohr were both right. What has been the wrong assumption over the years is that the light is generating the…

But then every point in space has it's own clock, so you'd have gazzilions of tiny clocks instead of one big global clock that tickets for the entire universe/reality.

Or perhaphs if we do have one big global clock, your distance from it warps/distorts other parts of the reality at each point in space? Maybe there is a limit to how far this heartbeat travels (edge of the universe)?

You can also then ask, at what speed or clock cycle is reality "rendering" and is it the same speed everywhere? It would seem each point renders itself and there would be no big global processor doing the rendering.

Then finally if you really want to dig deep, ask why is it being rendered to begin with. Might need some psychedelics for this one instead of math.

What if there are no clocks nor any points, what if matter is just a condensate of frequencies/sound/harmonics - that is, there is a "great piano player" and the "sound" it emits is the universe, just a side effect. If it stops playing, the universe disappears/collapses into nothingness.

note: A point here referring to a point in a massive 3d grid of points.

Re: It’s time to admit quantum theory has reached a dead end

#189

As former amateur physicist, who read a couple books over the years :) To me it's quite simple. We haven't detected what is causing the waves that the particle of light is riding on. The particle of light is like a surf board, riding a wave and will always hit the shore in the interference pattern. Einstein and Bohr were both right. What has been the wrong assumption over the years is that the light is generating the…

Not saying you're wrong in the slightest, but why would our universe be like a computer? When our understanding of the universe was very primitive we thought everything was alive (animism). Then a little more technology and we thought the universe was like an orrery or a clock (mechanism)[0]. Then a little more and we think it was like a computer (turingism?) Occasionally you'll hear it's like a hologram, a simulatio…

What's the difference between a clock and a computer? And there's no difference between computer and computer simulation.

Being a hologram is something I see as a significantly different type of comment. That's about how a sphere of space is mathematically equivalent to a flat 2d shell using equivalent but warped physics. It doesn't change anything about the nature of the universe except sort of the number of dimensions. And it's orthogonal to those ideas.

I'm not sure how to categorize the graph thing but it's not widespread at all.

Re: It’s time to admit quantum theory has reached a dead end

#190
post #73

As former quantum physicist, I find it little troubling to read "quantum theory has reached a dead end" in specific reference to the interpretation of quantum mechanics. Most quantum physicists could not care less about how quantum mechanics is interpreted when it makes highly accurate quantitative predictions, and there are still plenty of interesting open problems for quantum theory (e.g., related to the practical…

As a former quantum physicist who has just decided to go back into quantum computing, this was my take as well: Introductory quantum physics courses may still include wave-function collapse and all that nonsense, but I have not met many physicists who use this as a mental model.

To be a bit more specific as to how _decoherence_ solves this, one way to see it is that classicality (i.e. observables having specific values) is an emergent property in the limit of near-infinite degrees of freedom in the same way that e.g. thermodynamic properties (temperature etc.) are emergent properties of classical systems in the limit of near-infinite degrees of freedom.

Putting it on the edge, claiming that quantum theory is at a dead end is like claiming statistical physics is at a dead end.

One of my personal favorites for how to formalize this is the work on "pointer states" by Wojciech H. Zurek. There is a freely available Physics Today articls [0], and you can find surveys of further work e.g. in the introduction of [1].

[0]: https://arxiv.org/abs/quant-ph/0306072 Zurek, Decoherence and the transition from quantum to classical -- REVISITED [1]: https://arxiv.org/abs/1508.04101 Brasil, Understanding the Pointer States

Post reply on HN