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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?

#711

Post by mncharity »

dnautics wrote: post #516
mncharity wrote: post #369

Earlier quoted context omitted.

Oh my that facepalm dreadful. Thank you! That gives me a new high-water mark for misleading biomolecular visualization computer graphics content. Snagged a copy. When most everything is unmoving, it's "obvious"... well no, not to students, but... there's no pretense of doing anything other than stitching together an extremely selective set of "snapshots", to tell a completely bogus narrative of smooth motion. Here it…

you might like this render better: https://www.youtube.com/watch?v=DR80Huxp4y8 here's the artistic director for the inner life of the cell (the worse one) going on and on about how "beautiful" the science of biology is: https://www.ted.com/talks/david_bolinsky_visualizing_the_won...

> artistic

Yeah. One might for example reduce reinforcement of the big-empty-cell misconception by briefly showing more realistically dense packing, eg [1], before fading out most of it to what can be easily rendered and seen. But that would be less "pretty". Prioritizing "pretty" over learning outcomes... is perhaps a suboptimal for education content.

> better

But still painful. Consider those quiet molecules in proteins, compared with surrounding motion. A metal nanoparticle might be that rigid, but not a protein.

One widespread issue with educational graphics, is mixing aspects done with great care for correctness, with aspects that are artistic license and utter bogosity. Where the student or viewer has no idea which aspects are which. "Just take away the learning objectives, and forget the rest" doesn't happen. More like "you are now unsalvageably soaked in a stew of misconceptions, toxic to transferable understanding and intuition - too bad, so sad".

So in what ways can samplings of a protein's configuration space be shown? And how can the surround and dynamics be shown, to avoid misrepresenting that sampling by implication?

It can be fun to picture what better might look like. After an expertise-and-resource intensive iterative process of "ok, what misconceptions will this cause? What can we show to inoculate against them? Repeat...". Perhaps implausibly intensive. I don't know of any group with that focus.

[1] https://www.flickr.com/photos/argonne/8592248739

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#712

Post by neop1x »

dmichulke wrote: post #648
rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

One approach is reductio ad absurdum: If Central Banks can create money without negative effects, then - why tax people? - why even work? Can't we just print enough money for everyone and live happily ever after? I realize these questions are quite provocative and their answering only explains if it will work but not how or when it will fail.

The gold standard ended in 1975. Since then, we have "virtual money", which are effectively made out of thin air at the time a bank borrows them to someone. Once they started this system there is probably no way back. But what effects has that done, are them all positive? I don't know. Some say it helps prevent the situation when rich would buy all the gold supply - banks can make more money for others. But - rich people can use stock markets and funds too. And look at one thing - the Appollo program started 1961 and completed 1975. I was quite shocked to see from the documentaries what technology they developed and had during the Apollo era. What US built during cold war. UNIX development started in 1970, right? So many awesome airplanes and technology around. It looks like what we have today is mosty (a great) improvement of many inventions developed before or around the end of Apollo and the end of gold standard. Now, that money is virtual, it looks like there won't be any major stock market crashes as they can intervene relatively easily. But why the space program basically died? NASA has just been talking about SLS for many years... Is it because politicians or bankers don't want that to continue? They could print money for it in minutes, couldn't they? Or would it be far more expensive than we think? Would printing so much money skyrocket the inflaction and bring the whole economy to its knees? Isn't by chance the "real value of work" now much higher than what inflation suggests? I read here about a year ago that some smart people are not working in scientific R&D but instead making AI to improve marketing for online e-shops selling products people don't really need. Despite many startups claiming breakthroughs daily in the news, I don't feel it that way. Those are small pieces one by one. It looks to me big human progress has stagnated somehow. Maybe the smart people are not motivated enough to do the real big things, or maybe it is because there is no need to compete with Russia anymore. But hey, there have been talks about helicopter money recently - giving people money for no reason. Does that look like a great way to improve things? We live in peace - thanks for that - but it seems to me that somehow there is no motivation to do big things anymore. It seems better to just pour the money in the stock market, consume goods and services, watch Netflix and play games. Consume gas and limited Earth resources with virtual unlimited paper money. Taxation probably doesn't make sense anymore, it is there just for historical reasons, from the time bank notes were backed by gold.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#713

Post by tabtab »

cousin_it wrote: post #601
arkanciscan wrote: post #173

Quantum Computers. Not like I'm five, but like I'm a software engineer who has a pretty decent understanding of how a classical turing machine works. I can't tell you how many times I've heard someone say "qubits are like bits except they don't have to be just 1 or 0" without providing any coherent explanation of how that's useful. I've also heard that they can try every possible solution to a problem. What I don't u…

I think there's no way to understand quantum computing without first understanding some linear algebra, specifically tensor products. How ten 2-dimensional spaces give rise to a 1024-dimensional space, how the Kronecker product of three 2x2 matrices is an 8x8 matrix, and so on. If you're comfortable with that, here's a simple and precise explanation of quantum computing: 1) The state of an n-qubit system is a 2^n dim…

What about some kind of interactive simulation, kind of like playing with a graphing calculator? People tend to relate to things better by tinkering and playing with parameters to observe the impact on results. Analog experimentation is how we learned most Newtonian physics.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#714

Post by javajosh »

abiogenesis_123 wrote: post #570
javajosh wrote: post #527

Earlier quoted context omitted.

This question interests me as well, and I've done some thinking about it over the years. In particular, what I'm interested in is a hypothetically simplest object that can reproduce in a solution of simpler components, along with some differentiating characteristic. For example, maybe you have toroids that pick up particules, grow the torus until its too big, and then splits - and the ends of both halves click togeth…

> NB I'd expect none of these very simple machines to survive to present day - in fact, I'd imagine there to be several generations of early life, each obliterating/consuming/sublimating the ones before. That's another really interesting axis of this topic -- why was early Earth special? There may be no environments on Earth today that are like early Earth, but we could probably recreate them. Wouldn't we then be abl…

>Wouldn't we then be able to witness abiogenesis?

It may happen quite infrequently, and only because it happened in a large, lifeless (but 'nutrient' rich bath) did it have a chance to amplify. What's interesting to me is that it only has to happen once.

Yes, Earth's specialness is interesting, too, and counts for what I believe are the best reasons to believe in God. Earth has so many amazing qualities: it is a cozy distance from the Sun (temp), tilted quite a bit (seasons), with a molten core (cosmic ray protection) and a huge moon (tides, nocturnal light). All of these may be necessary conditions for life to arise, and they are all, as far as we know, quite rare individually, and astronomically unlikely in combination.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#715

Post by elteto »

robertakarobin wrote: post #690
traK6Dcm wrote: post #586

Earlier quoted context omitted.

The short answer: What exactly the "price" shown on the exchange website is depends on the exchange. Typically it's the last trade price or the mid price (average of best bid and offer). There really is no such thing as a single "price" because the price will depend on the quantity and direction you are transacting in. Long answer: You need to understand how the Limit Order Book works. I wrote up something about this…

Thank you! So each exchange has its own formula for determining the price that gets shown on the ticker? Let's say someone owns shares in a very low-volume stock — one that gets a couple trades a day, at most. Could they artificially increase the share price by offering their shares at a high price, then using a second account under their control to immediately buy them at the inflated price?

Yes, this is called cross-trading [0] and AFAIK is forbidden by the SEC.

[0] https://www.risk.net/definition/cross-trade

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#716

Post by madhadron »

lisper wrote: post #457
johnmorrison wrote: post #451

Earlier quoted context omitted.

It only has direction + magnitude right? (±h/4π)e_i for some unit vector e_i. So it can be written as a vector? No?

It's a vector. madhadron doens't know what he's talking about. (To be excruciatingly precise, it's a ray in Hilbert space. But that's close enough to a vector for the purposes of HN comments.)

I actually do. It's a spinor. It doesn't transform the way a vector does.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#717

Post by mjewkes »

tabtab wrote: post #713
cousin_it wrote: post #601

Earlier quoted context omitted.

I think there's no way to understand quantum computing without first understanding some linear algebra, specifically tensor products. How ten 2-dimensional spaces give rise to a 1024-dimensional space, how the Kronecker product of three 2x2 matrices is an 8x8 matrix, and so on. If you're comfortable with that, here's a simple and precise explanation of quantum computing: 1) The state of an n-qubit system is a 2^n dim…

What about some kind of interactive simulation, kind of like playing with a graphing calculator? People tend to relate to things better by tinkering and playing with parameters to observe the impact on results. Analog experimentation is how we learned most Newtonian physics.

Strilanc, who works on the google quantum team, has a simulator here: https://algassert.com/quirk

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#718

Post by elteto »

atomicnumber3 wrote: post #410
robertakarobin wrote: post #370

If 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…

In your example, after the market maker posts the BUY 10 @ 100.0, your book is:

    SELLING 100 shares @ $10.02 
    SELLING 200 shares @ $10.01
    SELLING 100 shares @ $10.00
Wouldn't the SELL and the BUY @ 10.00 get matched immediately in this case?

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#719

Post by henearkr »

rsp1984 wrote: post #603

Macroeconomics. Central banks are "creating" a trillion here, a trillion there, like nobody's business. But what are the consequences? What is the thought process that central bankers have gone through to make these decisions? Also why, exactly, are they buying the exact assets that they are buying (govt. debt, high-yield bonds, etc..) and why not others (e.g. stocks or put money into startups)? And then, what happen…

You cannot really "create" money, but they do it anyway because the natural pricing mechanisms (laws of supply and demand) take a non-null time to reach a new equilibrium.

So the aim is to take advantage of this transient fluctuation and the way the ripple propagates.

But even if in a perfect (or future) world, everybody reprices instantly all the goods relatively to the new amount of available currency, there is still an effect which is how is distributed the newly "created" currency: who get the new shiny coins? So this is equivalent (if the repricing is done) to a kind of global instantaneous tax-and-subsidies. They tax everybody by the percentage of currency created (relative to the total existing amount), and the lucky ones receiving the fresh money are getting thus a subsidy.

Re: Ask HN: What scientific phenomenon do you wish someone would explain better?

#720

Post by aeternum »

slazaro wrote: post #282
harimau777 wrote: post #246

I 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…

Gravity is explained that way, it is a curvature in spacetime (4D): https://www.youtube.com/watch?v=CvN13ZE544M
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