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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?

#811

Post by abecedarius »

mncharity wrote: post #388
vikramkr wrote: post #174

Earlier quoted context omitted.

A few different things help everything work: 1) Compartmentalizing of biological functions. Its why a cell is a fundamental unit of life, and why organelles enable more complex life. Things are physically in closer proximity and in higher concentrations where needed. 2) Multienzyme complexes. Multiple reactions in a pathway have their catalysts physically colocated to allow efficient passing of intermediate compounds…

The common theme there is constrained proximity. To give random chance more of a chance. My favorite illustration was a video of simulated icosahedral viral capsid assembly. The triangular panels were tethered together to keep them slamming into each other. Even then, the randomness and struggle was visceral. Lots of hopeless slamming; tragic almost but failing to catch; being smashed apart again; misassembling. It w…

Coincidentally I'm previewing PBotC just now. It looks really promising. Do you know roughly when the new edition is expected? Or if you have any favorite books on how things work at that scale, I'd be grateful for the pointer. (I've read a popular book by David Goodsell and am halfway through a somewhat deeper one.)

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

#812

Post by borramakot »

Viliam1234 wrote: post #650
aazaa wrote: post #236

Sort of meta, but I always shudder when someone says that science has "proven" something. What sets science apart from most other methods of seeking answers is its focus on disproof . Your goal as a scientist is to devise experiments that can disprove a claim about the natural world. This misconception rears its head most prominently in discussions at the intersection between science and public policy. Climate change…

One thing that rubs me the wrong way about this "no proof ever, only disproof" attitude is that it advantages the new hypotheses too much. Any hypothesis that I invent at this very moment, is from this perspective in the best position a hypothesis can ever be. There is no disproof. There is even no coherent argument against it, because I literally just made it up this second, so no one had enough time to think about…

I've not read Popper directly, so I'd be interested in his actual argument on this.

But, I wonder if you can describe H1 as being a stronger hypothesis than H2 by virtue of withstanding more and higher quality attempts to disprove it?

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

#813

Post by izuchukwu »

0xff00ffee wrote: post #756
izuchukwu wrote: post #729

Earlier quoted context omitted.

This feels like the high-level missing piece in my understanding of its use. Do you know any resources that expand on QC’s effective potential more from this point of view?

Sorry, I do not.

All good. I appreciate the perspective you’ve given!

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

#816

Post by BowBun »

OkayPhysicist wrote: post #600
slazaro wrote: post #282

Earlier quoted context omitted.

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.

Fascinating thought! Makes sense though. Given n inputs and outputs, you could literally make an if-statement that solves nothing but gives you the 'right answer'. Actually understanding the fundamentals (often unseen) of a problem to then create an elegant, holistic solution that almost prophetically seems to predict the future is the current peak of human thought achievement, IMO.

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

#817

Post by mech422 »

emblaegh wrote: post #507
mech422 wrote: post #495

BlackHoles - where does the 'extra' mass/gravity come from? I've been watching a lot of documentaries lately, and I can't figure out how a star that _radiates_ light, collapses and suddenly light can't escape? Doesn't that mean the blackhole has more mass/gravity then the star that created it?

What teachers tell you in school is that as you get close to a uniform sphere the gravitational force increases with the square of the distance to the center of such sphere. What they don't tell is that once inside the sphere the force decreases linearly, because the planetary mass ahead of you is partially balanced by the mass behind you. With this you can see that the gravitational pull of a planet/start/spheroid i…

Yeah - a lot of mass gets 'blown away' which really made it even stranger that gravity increased. While I found your explanation illuminating, I still don't see how you can end up with 'more' gravity then you started with? Mass determines gravity right ? not volume ?

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

#818

Post by mech422 »

filmor wrote: post #506
mech422 wrote: post #495

BlackHoles - where does the 'extra' mass/gravity come from? I've been watching a lot of documentaries lately, and I can't figure out how a star that _radiates_ light, collapses and suddenly light can't escape? Doesn't that mean the blackhole has more mass/gravity then the star that created it?

It doesn't, it's just a lot denser. A star has a lot of inner pressure from the ongoing fusions inside of it. When these stop or reduce, the star collapses from its own gravity, as soon as its radius is smaller than the event horizon (i.e. the radius at which the escape velocity exceeds the speed of light) you have a black hole.

That's basically what I keep seeing in the documentaries, but it's still not sinking in. For instance, being denser I could see it making a 'deeper' 'dimple' in the rubber membrane demos they use...but it would also be a much smaller diameter dimple, so only things really close and really small could 'fall' into it ?

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

#819

Post by sooheon »

wizeman wrote: post #800
sooheon wrote: post #573

Earlier quoted context omitted.

Why isn't the MWI another form of hidden variables (a supremely non-parsimonious one at that), where the hidden variable is which of the many worlds you happen to inhabit?

I think you can make an argument for viewing it that way, depending on exactly what you mean by "you". But IIUC, one of the remarkable things about MWI is that it would be a local hidden variable theory! This is a very important property to have because the principle of locality is deeply ingrained in the way the Universe behaves. Note that (almost?) no other quantum interpretation is both realist and local at the sa…

For it to be local (causality does not propagate faster than light), it must be superdeterministic (all the many worlds that ever will be, already are). For it not to be superdeterministic (many worlds decohere at the moment of experimentation), it is also not local (the decoherence happens faster than the speed of light, across the universe).

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

#820

Post by wizeman »

sooheon wrote: post #819
wizeman wrote: post #800

Earlier quoted context omitted.

I think you can make an argument for viewing it that way, depending on exactly what you mean by "you". But IIUC, one of the remarkable things about MWI is that it would be a local hidden variable theory! This is a very important property to have because the principle of locality is deeply ingrained in the way the Universe behaves. Note that (almost?) no other quantum interpretation is both realist and local at the sa…

For it to be local (causality does not propagate faster than light), it must be superdeterministic (all the many worlds that ever will be, already are). For it not to be superdeterministic (many worlds decohere at the moment of experimentation), it is also not local (the decoherence happens faster than the speed of light, across the universe).

I'm sorry but I don't follow.

If you take the Bell test experiment where Alice and Bob perform their measurements at approximately the same time but very far apart, I think you and I both agree that when Alice does a measurement and observes an outcome, she will have locally decohered from the world where she observes the other outcome.

But I don't see why the decoherence necessarily has to happen faster than the speed of the light.

It makes sense that even if Alice decoheres from the world where she observes the other outcome, the outcomes of Bob's measurement are still in a superposition with respect to each Alice (and vice-versa).

And that only when Alices' and Bobs' light cones intersect each other will the Alices decohere from the Bobs in such a way that the resulting worlds will observe the expected correlations (due to how they were entangled or maybe even due to the worlds interfering with each other when their light cones intersect, like what happens in general with the wave function).

I admit I'm not an expert in this area, but is this not possible?

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