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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?

#461

Lot's of quantum related phenomenon here, but what keeps bothering me is that while I get it that light is both a wave and a particle, but I have no clue what that means. I mean, a wave of sound, is made from air particles, a wave of ripples in a pond is made of movement of water molecules. In the double slit experiment, it's explained that the single photon has to be "interfering with itself", so I don't get it if b…

Sorry, don't have time to unpack all this, as some are things that scientists understand, but some are so deep that ... not. When talking about light or radio waves, you're probably talking about Classical Electrodynamics, which does not include the notion of a photon. In Classical EM, light is an EM wave in the sense that if you look at the electric field E or magnetic field B (of a plane wave) at a fixed point in s…

Wow, any chance with a few MooCs in physics I’ll be able to understand this better? Or it needs years of study. I’m worried about the math mostly (Ms in CS, but I got Bs in all the math classes :))

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

#463

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 found Quantum Computing Without The Physics epicly helpful. https://arxiv.org/abs/1708.03684

It explains in terms a computer scientist can understand. As in: it sets out a computational model and explores it, regardless whether we can physically realize that machine.

Hope this helps!

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

#464
Abiogenesis. 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 baking soda and vinegar volcanoes to me typing this question, however.

What's the playing field look like for proto-life? How "smart" are the simplest molecular interactions? What does almost-replication look like? Could we use a computational model for this?

Not sure how much of this is known, but I'd love to hear an expert paint a picture of their mental model of the subject.

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

#465

Earlier quoted context omitted.

It literally feels as if I'm being transported back to that same night, starting to relive it all over again. It's entirely illogical but if you knew what happened it might make more sense (happy to elaborate here and give a brief description of what happened/why it messed me up so bad, I'm perfectly okay to talk about it now).

I'd be interested to hear your story. I've never used psychedelic drugs, but I find their effects fascinating.

I took 300ug of LSD recklessly on a particularly bad day for me, in a particularly uncomfortable setting.

Well, that night went bad. Really, really, life-alteringly bad. For the first time, I had a bad trip. And not like, some mildly uncomfortable thoughts. I got a bad feeling in my stomach from the moment I dosed, and I knew something was going to be different this time.

As I started to come up, the bad feeling and a dark presence grew, and I pulled out my phone. I started a timer, and I watched as the time slowed to a point where it completely stopped. I started looping, I would get up off the couch, walk a few feet, and be teleported back. Over and over.

I realized that I had gotten so high, that time was no longer moving. And if time was not moving, I could maybe never come down. I was stuck here forever. And then the hellish nightmare started.

I felt like I was losing control of myself, like something else was trying to take over, and whoever won the battle, that is the consciousness that would exist. The more I fought, the more painful things got. Pain the likes of which I no one can physically imagine.

Went upstairs and laid down in my bed, began going out of body. I started dying over and over in unimaginable ways in my head, trapped in loops. Pain beyond anything I've ever felt in reality, there was no limit. It was tied to my breath, I realized that it had been so long since I had breathed, I kept forgetting who I was and what was going on, and then I would catch a slight glimpse and remember and fight so hard to take another breath. And there was so much pain in fighting to "survive" and hold on to who I was.

Eventually, the pain/struggle became too much, and I "gave in" and said "okay, I give up, you win, I can't take it anymore, I'd rather die." And that's when it's stopped. There appeared this giant shape of light/energy that was every color at once, and colors we don't have words for, and it "touched me" (could have been me moving towards it, or it towards me, there wasn't really a concept of this).

When it "touched" me, what it "showed" me was something I later learned is called an "Ouroboros", the snake eating it's tail. It showed me what "infinity" really meant, and that was too much to handle and shattered my psyche.

In that moment my body/mind/soul felt like it was obliterated to pieces by some energy beam in the most excruciating, searing pain, and I woke up in my bed having just pissed myself.

It took a long time to piece myself back together after that one.

---

There are a lot of details I've omitted for brevity's sake, but this captures the gist of it.

The majority of my trauma has to do with anything related to loops: think Nietzsche's Eternal Return, general time-loops, fear of time-stopping, etc.

When I have panic attacks I have to stop myself from starting a stopwatch on my phone to make sure time is still moving because it'll cause a feedback loop and ratchet-up the panic, causing the time-dilation to increase in a vicious cycle.

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

#466

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…

Love the detailed explanation. Thanks. Once I saw Boeing at $120. I thought to myself. That’s dirt cheap and should buy. So I hit buy at market and lo behold I bought for $130. Wait! Whaaa! Did the exchange lie to me ? That day I learned a very hard lesson that there are infact two prices. Ask price and bid price. I wasn’t paying attention.

Now I try to always put limit orders. I put sell for Boeing at $150 with “good till cancelled” option. One morning I wake up to see they’ve been fulfilled. Wohoo! But the price had dropped down to $140. So I cashed in on the spike.

The market is crazy. I still don’t understand if. P/E ratios for some companies are through the roof (100+), why are people still investing in them like crazy? We don’t have a cov2 vaccine, millions of people don’t have jobs, why did the marker recover half it’s losses already? Shopify, Amzn, Zoom. WTF! Their charts seem hyped. Or may be I’m just plain wrong and don’t understand the fundamentals.

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

#467
post #391

I consider that there are 4 levels of scientific writing. 1) news articles/lay press - basically terrible and typically get things wrong 2) scientific lay press (scientific american, discover, science news) - get things right, but generally no data/citations or nuance 3) journal summaries - get things right, citations and data for everything. Good summary of the latest scientific thought on a topic. Tend to push a po…

I was shoulder deep in primary source material (#4) on real-time fuzzy search and wasn’t able to make heads or tails of where everything fit. Until I found a #3 overview that referenced most of the primary sources and put them in context. That paper was worth its weight in gold! Do you have any tips for how to quickly find these #3 materials in other spaces?

The name for what you and the parent described is a review paper. I can't speak for Math or CS, but in life sciences the following techniques would work:

1. Search X and sort by citation count. High quality review papers get cited A LOT, typically in introduction sections of primary research papers. Alternatively, google "[X] review" or "best review paper on X".

2. Look for review journals. Many fields will have journals who only publish reviews. Nature has several such publications for example.

3. Look for the top journals in the space (start by sorting by impact factor) and see if they have review sections. If they do, try to search those sections. Most journals will reach out to top labs in a space and request that they write a review on a subject if the journal editors feel one is needed.

4. Ask someone in the field. Any researcher should be able to immediately point you to canonical reviews in their space.

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

#468

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…

If you see a single share price listed, that is the price of the last sale that occurred. Now that can either mean that someone bought a share that someone else was selling or that someone was selling a share to someone who was offering to buy. The shares are listed as a series of buy and sell orders in what's called an order book. If the price a share was sold at was 100$ and you think it will go a bit lower, you co…

How does it work with futures?

My understanding is that I buy a contract for 100 shares at a future date of my choice.

So let's say stock XYZ is currently trading at $20, and I buy a futures contract for $100 for Jan 1st 2021.

I don't have enough money sitting around to buy those 100 shares, so let's say XYZ is trading at $200 by Jan 1st 2021, That means I have a contract where I can buy 100 of them at $100 and immediately sell them for $200, so in theory it's a $10k profit.... but because I don't have enough money to actually do that, do I just sell my future for something close to 100* $200 (because someone with enough money will buy it and do the actual trade?)

What happens if it's already well over $100 long before Jan 1? Can I just set a price and sell it whenever I want like a can with a regular share?

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

#469

Earlier quoted context omitted.

It's accurate. QC is just linear algebra with complex numbers, plus probability extended to the complex domain. Why that's useful is something I'm still struggling with as well.

I'd assume it's the speed advantage, but the only problem I can think of that would require that type of exponential speed is cracking hashing algorithms which just seems destructive and counterproductive, like building a digital nuclear bomb - and from my very limited understanding that's a long ways off from being achieved. I assume there's probably many more complex computational problems outside of my domain that…

Many problems require lots of huge matrix multiplications—think simulations of physical systems, i.e. weather systems or molecular interactions, or numerical optimization.

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

#470
post #56

I find most explanations of the Equivalence Principle that lies at the foundation of General Relativity to be very lax. To wit, the idea is that you cannot distinguish whether you are in an accelerated frame or in a gravitational field; alternatively stated, if you’re floating around in an elevator you don’t know whether you’re freefalling to your doom or in deep sideral space far from any gravitational source (thoug…

I wanted to thank everybody who took the time to explain this. Thank you.
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