Ask HN: What scientific phenomenon do you wish someone would explain better? • Hacker News Board

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

#71

Post by Dutchie85 » Sun, Apr 26, 2020, 9:48 PM UTC

Why does time slow down/go faster with movement compared to another object.

The well known example that if you travel into space you'd gain let's say 5 years and people on earth 25 in the same time or so.

I just don't get it and I can't find any logic explanation.

For instance: Two twins who came to live exactly at the same moment in the year 2000 and both die on their 75th birthday at the same time. One travels into space, the other stays on earth. Earth-brother dies on earthyear 2075,space-brother dies in earthyear 3050 or so...

I know its Einstein's point but that just doesn't instantly make it correct to me.

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

#72

Post by pjungwir » Sun, Apr 26, 2020, 9:48 PM UTC

Entropy. Sometimes you read that it's a measure of randomness; sometimes, information. Aren't randomness and information opposites?

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

#73

Post by vvoyer » Sun, Apr 26, 2020, 9:49 PM UTC

vertical alignment in CSS

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

#74

Post by phkahler » Sun, Apr 26, 2020, 9:50 PM UTC

Wave function collapse. As far as I can tell there is no discernable difference between a particle whose wave function collapsed (perhaps via measurement with another entangled one) and one that hasn't.

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

#75

Post by daenz » Sun, Apr 26, 2020, 9:51 PM UTC

Why a flat earth is impossible.

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

#76

Post by tomp » Sun, Apr 26, 2020, 9:51 PM UTC

Flight. Apparently "air flows faster on the top side of the wing, lowering the pressure" is an incomplete explanation; I even heard we don't completely understand why it works (?!?).

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

#77

Post by tomp » Sun, Apr 26, 2020, 9:53 PM UTC

daenz wrote: post #75

Why a flat earth is impossible.

You'd see Mount Everest.

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

#78

Post by sam » Sun, Apr 26, 2020, 9:54 PM UTC

Mach's principle. Why is there a "preferred" rotational frame of reference in the universe? Or as stated in this Wikipedia article,

"You are standing in a field looking at the stars. Your arms are resting freely at your side, and you see that the distant stars are not moving. Now start spinning. The stars are whirling around you and your arms are pulled away from your body. Why should your arms be pulled away when the stars are whirling? Why should they be dangling freely when the stars don't move?"

https://en.wikipedia.org/wiki/Mach%27s_principle

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

#79

Post by JJseiko » Sun, Apr 26, 2020, 9:54 PM UTC

vvoyer wrote: post #73

vertical alignment in CSS

this made me laugh!

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

#80

Post by HenryKissinger » Sun, Apr 26, 2020, 9:55 PM UTC

ramboldio wrote: post #55

Fourier Transforms. I'd wish I had a intuitive understanding of how they work. Until then I'm stuck with just believing that the magic works out.

Every analytical function, like f(x)=x^2-log(x+1), or signal, like a radio signal, can be rewritten as as infinite sum of sines and cosines. The Fourier transform helps you break down these components for you