observantTrapezium

Rumania and Makedonia probability the closest to the country's native name.

EM and gravitational waves are seen as analogous because as I wrote, they are produced by acceleration of charges and masses, respectively. The physics behind them is very different (described by Maxwell's equations for EM and Einstein field equations for GW), but all systems that have waves in them (including sound in the air, waves on the surface of water etc.) can be approximated as linear for small perturbations, which means that they satisfy the wave equation at that regime.

It's not me who didn't use a tool, it was the other guy.

Only because we are used to it.

I just had to coordinate an online meeting with some guy at a company, I had no idea where he's based but he suggested time slots in EST (I'm in Toronto). I asked him twice if he's sure, thinking he may be based outside of North America and doesn't know that Toronto currently follows EDT which is GMT-4h, and he just responded "Eastern Standard Time".

And of course he actually meant EDT. Turns out he is based in North America, just dumb.

Fuck timezones, but more than that fuck daylight saving time. You want an extra hour of sunshine after work in summer? Shift the work schedule, not the fucking clock!

It's a map of the AƧU

The balrog was already awake, but maybe wasn't paying attention 😜

They are quite similar to electromagnetic waves, but also quite different. They are produced by masses accelerating (just like EM waves are produced by charges accelerating), and indeed cause orbital decay. But this orbital decay is only important in relativistic systems (so the Earth, which is orbiting the sun at 0.0001 the speed of light, is not going to fall into the sun because of gravitational waves).

See my response below to Captain Aggravated about how dilute those large stars are.

It's an interesting question whether anybody would actually feel spaghettification 😁 I actually don't know. You can use physics to calculate the proper time derivative of the tidal forces, but you need biology to define the start (and end...) of the process. My intuition says that it probably happens too fast, so once the tidal forces are strong enough to be perceptible, they grow strong enough to rip you apart before you realize (again, just a hunch).

Yep, you got it right. The accretion disk is actually really flat. Those images are produced in simulations that take into account the curved (and very complex) paths light takes in the vicinity of a black hole. These images really depend on the angle between the line of sight and the disk.

In the case you are unlucky enough to encounter the black hole "heads on" and fall into it radially, the proper time timescale to spaghettification is the size of the event horizon divided by the speed of light. The most supermassive black holes will have a horizon of around one light day, so that's what we're working with, a matter of days. If you come in on the most tangential orbit possible though, I guess you're buying some time but I've never heard that it's supposed to take many years of proper time (I doubt that claim a little bit, but haven't calculated myself).

Astrophysicist here. Yes, space is crazy, but interesting things to keep in mind:

1. The size of a star is determined by something called the photosphere. With those extremely massive stars, you can be hundreds of millions of kilometres "inside" and not yet know it.
2. Similar story with supermassive black holes, from the perspective of an astronaut falling in, they wouldn't really be able to tell when they cross the horizon because the tidal forces there are very small (they will inevitably fall towards the centre and get spaghettified at some point)