I liked your answer without you acknowledging my lack of intelligence. Thank You!
Maybe I didn't phrase it correctly. With the already known expansion of the universe, is everything in the universe getting pulled along for the ride? You know, getting stretched out along with expansion, or is everything staying static while expansion is making the distances between unearthly things we can see through lenses appear growing farther apart, while we still live in this small part of space
And also, I'm really curious if our solar system is in a static place, or because of lack of gravity it's all in a free fall.
It’s the latter. What’s even more fascinating is that the universe is expanding faster than the speed of light, so in light years, the size of the universe is bigger than the age in years of the universe, and that doesn’t contradict relativity’s speed-of-light limit for everything including even propagation of gravity itself because nothing is moving faster than light, rather space itself is expanding over (relative) time, so some parts of the universe have forever been partitioned from us, ie no matter how long we wait, light from those regions can never reach us, unless the universe’s space starts to shrink again, that is.
Yes, huhuh is right. Earth itself isn't getting stretched out as part of the expansion, and neither is the solar system. That's because they are gravitationally bound, i.e. different parts of Earth/the solar system are pulling on each other via gravity which keeps them from getting carried along with the expansion. Even galaxies mostly aren't getting pulled apart. It is on even larger distance scales that expansion comes into play.
Here is a link to a cool paper that explores some of the stuff huhuh was talking about regarding which parts of the universe we can see and affect:
This paper explores the fundamental causal limits on how much of the universe we can observe or affect. It distinguishes four principal regions: the affectable universe, the observable universe, the eventually observable univ...
Also I didn't understand this part: "I'm really curious if our solar system is in a static place, or because of lack of gravity it's all in a free fall." I'll just point out that in physics, free fall means moving freely under the influence of gravity. So if you jump off a cliff, there sure is gravity, but (ignoring air resistance) you are in free fall. Likewise, our solar system as a whole is indeed affected by gravity, and is in free fall toward the center of our galaxy (but also with lateral velocity, so it is orbiting). Not sure if that helps answer the question.
It is on even larger distance scales that expansion comes into play.
Expansion of what? That's where it all falls down. Science isn't equipped to handle metaphysical questions like that. Not investigating the essence of the stuff they call "space," "interstellar medium," etc.
Metaphysics? Things are getting further apart from each other. Light gets stretched out as it travels over these regions. We have models that describe all of this mathematically. The word 'space' doesn't appear in any of those models. Human language and everyday concepts like 'space' are a simplified, lossy shorthand for describing the gist of what is going on to those who don't want to dive into the mathematics. You could debate which words are appropriate, but that is just an argument about words, not some deep problem with science.
Metaphysics? Things are getting further apart from each other. Light gets stretched out as it travels over these regions. We have models that describe all of this mathematically.
Math isn't real, models aren't real. They are just ideas.
How does light (a wave, supposedly) get "stretched out?" Either explain what the wave medium is, or explain how else the light knows the observer is moving away from its source. Sometimes the observer is moving away even faster than light (supposedly) and yet the light still gets there, heavily redshifted.
So what's actually there, between the source and observer? To paraphrase Deep Thought, what actually IS it?
Follow up question, is there really any valid basis for the concept of simultaneity on an intergalactic scale? Can you really say one galaxy "is" a billion parsecs from another? If not, can you really say it "has" an particular velocity relative to another?
There is no physical way that anyone can detect the motion of distant galaxies. It is pure speculation.
I offer you an alternative theory. All matter did not form in a single Big Bang event. Instead, matter continuously forms on the outer edges of spiral galaxies, and matter gets continually recycled in the galactic centers. This is why all the Milky Way stars travel at the same speed, not because of Dark Matter. Global Warming is a direct result of increasing proximity to the center of the Milky Way.
Cosmology is science's bad attempt to do metaphysics. Not philosophers!
Here's a different angle on the universe for you: it's too fricking big. However it came into existence, there's just too damn much of it. Everything is too far apart. Most of it is just pointless star formation and stuff drifting around. Nearly all is either too hot or cold, inhospitable to all life.
Once you get over being awestruck by it, this reality eventually sinks in.
Anyone who thinks the universe will expand bigger than 2,600 miles across is a complete idiot.
Cosmology is science's bad attempt to do metaphysics. Not philosophers!
Here's a different angle on the universe for you: it's too fricking big. However it came into existence, there's just too damn much of it. Everything is too far apart. Most of it is just pointless star formation and stuff drifting around. Nearly all is either too hot or cold, inhospitable to all life.
Once you get over being awestruck by it, this reality eventually sinks in.
Anyone who thinks the universe will expand bigger than 2,600 miles across is a complete idiot.
There is no physical way that anyone can detect the motion of distant galaxies. It is pure speculation.
I offer you an alternative theory. All matter did not form in a single Big Bang event. Instead, matter continuously forms on the outer edges of spiral galaxies, and matter gets continually recycled in the galactic centers. This is why all the Milky Way stars travel at the same speed, not because of Dark Matter. Global Warming is a direct result of increasing proximity to the center of the Milky Way.
What? We CAN tell whether distant galaxies are receding or approaching via their Doppler shifts: redshifts indicate recession and blueshifts indicate approach.
^ this interpretation of red/blue shift is problematic because the "velocity" of light itself is independent of the relative motion of source and observer.
again, the metaphysics of the situation is neglected. If there's a wave there waving, what's the medium? Why does relative motion affect wave frequency but not the speed of the wave itself?
In the universe long, long ago some little people experimented with fusion technology and someone made a little mistake when they plugged in their machine. And BOOM!
It is on even larger distance scales that expansion comes into play.
Expansion of what? That's where it all falls down. Science isn't equipped to handle metaphysical questions like that. Not investigating the essence of the stuff they call "space," "interstellar medium," etc.
Really “all”? The entirety of physics falls down because it hasn’t explained everything there is to explain? Physicists are very much investigating the very essence of what space and time even mean or if the universe is even real, but they don’t have all the answers.
If you meant to allude to intelligent design as the alternative, good for you. It’s not a practically useful theory because it doesn’t help us make any verifiable predictions.
It’s predicated on something forming out of nothing. Can someone explain that?
I think your mistake here is saying the question is about the Big Bang theory. Now everyone is just saying that the Big Bang theory doesn't say something came from nothing which isn't helpful to you.
The unintuitive thing for me is that either "something" came from nothing (and I mean no space, no time, no laws of physics or anything at all) or else "something" has always existed. Maybe a different mindset or completely new physics will explain it but until then it's a mystery (at least to me).
There is one theory that suggests that our present universe could well be the inside of a black hole. We usually think of black holes are super dense forming a density singularity but that is only at its center. Physicists have done calculations to consider the volume of a black hole as that of its event horizon (the most reasonable definition of a black hole’s volume) and its mass and it turns out the overall density of a typical blackhole is comparable to our universe’s. We can’t see or know anything outside a black hole’s event horizon.
So, long story short, our entire universe could have become a supermassive blackhole from a dying supermassive sun, and there might be many such blackhole universes “outside”.
Now you’d want to know where all that came from. It could all have always just been there. We don’t really understand what time is anyway.
^ this interpretation of red/blue shift is problematic because the "velocity" of light itself is independent of the relative motion of source and observer.
again, the metaphysics of the situation is neglected. If there's a wave there waving, what's the medium? Why does relative motion affect wave frequency but not the speed of the wave itself?
EM waves (like light) can propagate through a vacuum and don’t need a medium. It’s a strange question to ask why relative motion affects frequency but not the propagation speed because the two are unrelated dimensions. The constancy of speed is indeed counterintuitive and was perhaps the single biggest insight in all of modern physics by a person whose very name is used as a synonym for smartness.
