Nobody ever said that acceleration is relative. Were you even listening in school? ;-)

It’s January that there won’t be one, as he won’t take questions at the end of December.

Yes, right?

He didn’t imply that dark matter aren’t captured by black holes. He was describing how they lack the “stickiness” to get one started, which is why dark matter is distributed thinly throughout the universe. You’d need enough gravitational force to get it localized.

@@chemquests And thus the last question in my comment. For the non physicist it seems like the existence of dark matter could be proven by showing that a planet or star (whatever the amount of mass needs to be to capture dark matter) exerts more gravity than what the visible matter accounts for.

@@retirementestimator9396 That's how we currently measure the mass of dark matter, except it's on the galactic scale instead of individual planets or stars. The stars at the edge of spiral galaxies are orbiting so fast that the would fly away from their respective galaxies if the galaxy only contained the mass due to the matter we can detect (stars and dust). Thus there must be more matter than we can detect electromagnetically; or GR is wrong, but then you're on the hook to find another theory that is as successful as GR which is super difficult.

​@@iziskin123 Another competing theory to dark matter is Relativistic MOND. Since it is hard to prove dark matter exists at the galaxy level, if one could theorize what it takes to capture dark matter in the gravity well of a star or planet then maybe dark matter would be easier to prove at that level.

That speed limit is the same, no matter who you are and how fast you are traveling relative to something else. ;-)

Jkknwm

Because it isn't real.

How dare you , Sir.

We can observe SOME of the first galaxies. Their numbers will get less and less in time. The CMB you are observing today is, of course, not the same CMB that you were observing yesterday. It came from a different volume.

@@schmetterling4477 I'll get to thinking on this. thank you

@@gtziavelis Yes, it's unfortunately not as trivial as some of the graphics suggest. Mathematicians have proven that it would take at least a six dimensional Euclidian space to "draw a map" of a flat four dimensional Minkowski spacetime. You can probably see where I am going here: humans can't really visualize all the properties of spacetime at once. We can only find intuitive explanations that cover fractions of reality one piece at a time. To build a working intuition is therefor hard and takes a lot of effort. Good luck!

Kids ruin parents lives ~ ~ So it’s a draw.

You want him to pay taxes? Wow, you must really hate rich people

@@Considerers Oh yeah, I am a ruiner of all good things : )

@@halexvr You do realize that you just played into the stereotype and assumed that we were hating on musk personally, right?

Let's not forget that this year Elon will pay more taxes than any other American has ever paid in a year before. Also he could have sold his shares in a way to minimize taxes but he did not, so he ended up paying more than he could have otherwise. I don't want to be called a fan boy. I'm just stating facts. It's a tricky thing taxing the rich, obviously they have the best tools to avoid taxes but you also can't just take away all their money or there is no motivation to succeed. The other side of it is that these billionaires don't just sit on this money in a bank account. It is invested into companies that employ millions of people, and develop new tech and ideas. I see both sides of the argument. All I know is our world would look a lot different if you removed all the billion dollar companies off the planet. Better or worse, who knows. There are arguments to be made that the private sector actually gets a better return on investment than the government, and it may be smarter to leave that money in the economy and let them use it for R and D etc.

@@themeach011 You are probably responding to the main comment, but personally i would say that i'm with ya, on average Elon is actually doing good. No hate here. Most rich people arent doing so good though, so lets keep our expectations high!

Interferometers are just clocks for nerds🤓

What causes gravity?? Mass. And what causes Mass? Matter, immersed in 3D space absorbs time... 🕰

Matter, accelerated though space/time increases Mass 🌐

No.