The rising cost and decreasing productivity of scientific research.
Ask HN: What scientific phenomenon do you wish someone would explain better?
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Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#592Earlier quoted context omitted.
No it doesn't. You know that the result of the computation for an individual qubit will be either 0 or 1 (otherwise it would be useless -- measuring only gives you one bit of information), so you construct the system such that after the computation is done each qubit will be aligned with the |+z> or whatever axis. The key point is that you have to be clever about how you construct the system for a given QC algorithm,…
OK but we're back on square one. If you can't read info from qbits without breaking the state of the whole freaking system then what exactly is that you reading? Doesn't the alignment info collapses superposition?
You design the algorithm so that it collapses the state into the right result.
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#593Earlier quoted context omitted.
Two conditions are necessary for a bicycle to remain upright (at least with most riders.) One is gyroscopic forces. Ever picked up a spinning hard drive? Notice that it feels strangely hard to turn in some directions? Same idea. The other is the feedback loop consisting of the bicycle and its rider. If the bike is stationary, it's hard to keep it upright because you have no assistance from gyroscopic forces. At low s…
That is indeed one of the authoritative explanations, and in a few seconds of ad-hoc search we may find at least two refutations from authoritative sources. For example, gyroscopic-forces-as-stabiliser don't need the Schwab paper's "ton of math" to be undermined. A simple counter-rotating wheel was used empirically at Cambridge to show as much, alongside notes that gyroscopic forces are relevant to the dynamics of a…
Sorry, I don't buy anything beyond what I stated. Those papers are exercises in violating Occam's Razor. Your quantum model makes more sense. :)
When you learn to ride a bike, you're simply training the feedback mechanism. Much like a PID controller, your brain has to keep track of the amount of error and null it out with proportional and integral terms (at least). Once those constants are dialed in, it's "just like riding a bike" -- they're yours for life.
Then there's the matter of learning which way to lean so that the gyroscopic instability inherent in turning doesn't send you into the nearest ditch...
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#594Abiogenesis. I understand that this is not considered understood but I'd be interested in hearing a qualified scientist talk about how we get from "dumb" matter to self-replicating, goal-driven matter. The closest I've ever heard anyone get (in a personal conversation) is that chemistry is about transformation, so "dumb" matter isn't really dumb in the sense that it's static. Still lots of hand waving to get from bak…
Did you read Nick Lane's "The Vital Question: Why Is Life The Way It Is?" It's all about this and it's great. Also take a look at https://www.quantamagazine.org/first-support-for-a-physics-t...
On Nick Lane's "The Vital Question":
I gifted myself The Vital Question in 2015 December. While Lane writes effectively without any mind-numbing jargon, the book still has quite a bit of technical chemistry (understandably). After the excellent first 80 pages, it took me a lot more will power to plough through. (I paused at page 112 to get back later.)
Once when I was reading the book on a plane, a seasoned biologist happened to be sitting next to me. When I told that it's the first book of Nick Lane that I picked up, he said: "I'd rather suggest you to pick up Laine's other book, Life Ascending, and only then get back to The Vital Question."
PS: FWIW, I've previously mentioned the above in an older thread, where an ex-biochemist chimed in to confirm the above advice: https://news.ycombinator.com/item?id=18714115
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#595Earlier quoted context omitted.
I had an aha moment with quantum computers a few months ago when reading an article that explained it as probability distributions. I don't think I have the complete understanding in my mind anymore and I wish I had saved the article, but looking into how quantum computers essentially serve as probability distribution crunching machines might help with your understanding.
So can they still do traditional deterministic(?) calculations? Or would that be somewhat akin to using machine learning to do your taxes; possible but just overkill? I've often heard it said that Quantum Computers can crack cryptographic keys by trying all the possible inputs for a hashing algorithm or something handwavey like that. Are they just spitting out "probable" solutions then? Do you still have to try a han…
Yeah, they can do deterministic calculations. You just avoid ever putting the quibits in a state where measurement gives probabilistic results. it would, however, be a ridiculous use of technology, like using a Neural net to simulate an XOR
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#596We aren't short of interesting problems.
To pick a couple fo them randomly, understanding amyotrophic lateral sclerosis or alzheimer would be terrific starts.
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#597If I buy a stock, does the price at which I agreed to buy it become the new share price on the stock exchange? Every article on "Where do stock prices come from?" seems to just talk at a high level about supply and demand. But where does the price come from at a nitty-gritty level? Is it an average of all existing offers or something? Do different exchanges and stock-ticker websites have different formula for calcula…
Disclaimer: I used to work in HFT Each exchange is basically its own world, with the exception of Reg NMS, which I'll get to in a sec. Let's task about order books. Each stock has its own order book. This might be an example of the book for AAPL: * SELLING 100 shares @ $10.02 * SELLING 200 shares @ $10.01 * SELLING 100 shares @ $10.00 * BUYING 100 shares @ $9.99 * BUYING 200 shares @ $9.98 * BUYING 100 shares @ $9.97…
> Sorry, I got a bit off-topic. But I love finance, so please forgive me.
You really didn't have to apologize! I thoroughly enjoyed your explanation. I can't recall how many times I've searched Google for "How are stock prices determined?" and come back with nothing. Your answer was better than 100% of everything else out there.
I'd love to learn more about this. Are there any books, blogs, etc. that you could recommend? Also, YOU should really consider blogging about this!
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#598Wormhole time machines.
The idea is, you can transform a normal [0] wormhole that isn’t a time machine into one which is by:
1) accelerating one end to high speed relative to the other
2) keeping on end in a lower gravitational potential than the other
Why are either of these considered meaningful statements, never mind correct?
In the case of 2 in particular, isn’t GR supposed to require smooth values? So any time dilation effect would be almost identical on a pair of points +δ and -δ from the throat? Making it similar to the case of a gravitational potential without a wormhole?
And in the case of 1, the more I think about it, the less I understand the concept. What is being moved? An imaginary clock that would’ve been in the part of the wormhole at the far end? The apparent speed as measured going through the throat will be zero regardless of the apparent speed of the same as measured when going the long way around.
[0] yes, I know
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#599I would like to understand how cellular biology processes actually work. Like, how do all the right modules and proteins line up in the right orientation every time? Every time I watch animations, it seems like the proteins and such just magically appear when needed and disappear when not needed [0]. Sometimes it's an ultra-complex looking protein and it just magically flys over to the DNA, attaches to the correct sp…
I recently started taking insulin. Check out the molecular structure for that. It blows me away how complex it is.
By molecular structure alone Insulin is one of the simplest proteins, even (though it's complex in ways you don't see by looking at a static picture of it, lifecycle, oligomeric interactions)
Re: Ask HN: What scientific phenomenon do you wish someone would explain better?
#600I don't know if this would be my "one question" if I could ask the most brilliant minds in science, but something that always bothered me: When I took physics they basically said "at first scientists were disturbed by the fact that magnets imply that two objects are interacting without any physical contact, but then Faraday came along and said 'the magnets are actually connected by invisible magnetic field lines' and…
Gravity and magnetism are two phenomena that I always imagined could actually be explained in higher dimensions (except we can't see those higher dimensions so it'd be just speculation). Imagine two circles in 2D that repel each other the closest you get them together, like magnets do. In 2D it would look like they're interacting at a distance, but maybe in 3D they're two cylinders that are a bit flexible, that are a…
There are models using higher-dimenions (and lower dimensions, and factional dimensions) to model physical phenomena, but the problem with a lot of them is that you end up with the "fitting n points to an n degree polynomial" problem. It's trivial to create a model that agrees with all observed data, it's a lot harder to make a model that accurately predicts unseen data.