Is it at all possible that instead of being pushed away, we are instead getting pulled toward something huuuuuge via gravity? As if we are falling into something way greater than ourselves? I thought this was a wild idea but after I Googled it I found out that there is such a thing as a “Great Attractor”. Something 150 million light-years away is literally pulling all nearby galaxies towards it but no one knows exactly what it is.
So how do we know there aren’t any other Great Attractors, Greater Attractors, ad infinitum?
Gravity bends light. You can literally detect large masses by how they distort the space around them. From what we can observe, space overall is pretty flat. AND we can measure where stuff is going using various proxies i.e the doppler shift, spectral lines, standard candles etc. If stuff was being pulled toward some mass, its going to cause deviations in how fast things are moving relative to each other. Which in the case of the great attractor, is what is happening. But if you are asking whether everything is falling toward something in every direction equally, the answer is no due to the shell theorm.
space overall is pretty flat
What do you mean by that?
Look at a piece of paper. Mark two points on it that are a good distance apart. Travel can only happen along the surface of the paper. When it’s flat, your time of travel depends on the distance between the two points on that paper.
Now dap a spot of glue next to one of the points and fold the paper in such a way that the other point comes to rest close to that glue. Wait for it to bind and then spread the paper a little without breaking the glue. That glued point is a wormhole, a place where two points of that flat 2D universe touch despite not being next to each other. Travel from point A to point B is now a shorter distance thanks to the wormhole. But there is no way in which the paper universe can be described as flat anymore.
Or think of a papermache ball, that’s also made from paper but if you travel long enough in one direction, you’ll end up where you started. Because it isn’t flat.
Now our universe is 3D not 2D, but from a higher dimensional perspective it has the same prooerties of flatness as that 2D paper has for us.
I think you need to let go of this idea that the big bang happened at a specific location or that we are moving away from or towards a point in space. There is no specific point from which all points in space are departing. Instead, every point in space is moving away from every other.
Consider the following!
Point at any object. That object is at some distance away from you in space which is also a distance away from you in time. For example, an object one light year away is one year into the past, as perceived by you.
Now, point in any direction. No matter where you point, if you extend the line forever, it intersects with the big bang. There is no place to which you can point, no direction, no infinite line you can draw that doesn’t include the big bang.
Now I’m even more confused 😄
The explanation was probably fine, I just can’t wrap my head around it
A lot of people describe the first moment of the big bang as infinitely small, dense, and hot. These descriptions may approximate that first moment of existence, but they slightly miss the mark because in the very first moment of existence, size, density, and temperature didn’t exist. There was nothing to compare anything else against.
Instead, let’s visualize that moment as infinitely same. Erase all thoughts of violent explosions happening very quickly and instead just imagine a single point of light. Not big, because size requires multiple things. Not small because it encompasses everything. Just one infinite same.
Now, since it’s hard for us to visualize change in an infinite void that is simultaneously nothing and everything, imagine that point of light as a magical tank engine at the front of a never-ending train. And our job as conductors of that train is to get to the caboose at the end.
The train cars could theoretically go in any order, but because we conductors are beings of time who need them to arrive on a schedule, we must visit each car in a precise order. And before we can access a car, we must make it unique by showing it something that has never been seen before.
For the first car, this is easy. We simply show it the tank engine at the front of the train. So, the inside of the first car transforms its interior into a copy of the tank engine it’s attached to.
But when we arrive at the second car, things are more complicated. The cars have already seen the tank engine. So, instead, we show the second car the first car. And the second car transforms into a copy of the first car and the tank engine attached to that. And inside the copy of the first car is another copy of the tank engine.
As you can imagine, the further down we get on this train, the more this starts to get out of hand. Copies of copies of copies abound. The magic train is powerful, but as mortal conductors of time, we worry our own powers may have limits. So, to reduce the burden on ourselves, we take some shortcuts. Instead of trying to visualize increasingly long nested copies of trains inside each new car we visit, we start to conceptualize these copies as amounts, or amplitudes. When we open the door to a new car, all of the amplitudes inside resonate and interact, becoming maybe more abstract than they are in reality. They form spatial dimensions and physical properties, as mediated by fundamental forces.
These aren’t set in stone, but determined by the lens through which we view them. And when we look through specific lenses, we see these forces causing certain repeated amplitudes to intermingle and stabilize to the point that even though all of the train copies are further nested when we step into the next car, we can recognize and identify some of the same structures, just shifted slightly in their spatial relationships since we last witnessed them in the previous car. We call these persistent formations matter. And as their shared spatial relationships cause them to cluster and coalesce, we refer to that as gravity.
While in the early cars, this continuum of space and matter is not impossible to conceptualize, the more cars we travel through, the more apparent it becomes that these increasingly complex objects are becoming more and more isolated from each other. At every scale of amplitude, each nested car is attached to its own tank engine. While these engines can interact with each other virtually, at the end of the day, they are all just virtual copies of the train we are on. It is entirely impossible for any one of these tank engines to travel so far that it reaches the edge of its bounding box. Because that bounding box is just a lens through which we imagine overlapping traits of increasingly many very similar objects. And the more of them we imagine, the more space is required to provide the virtual framework of this lens.
So, when we feel like we are experiencing random events in our small subsection of the universe, those events are not truly random, but instead the result of our precise position in the the universal train we’ve been virtually sliding through for over 13 billion years. The universe has become so large that it contains every possible event that could have happened in this span of time. The events are not random but calculated, and duplicated every moment so that every time we enter a new train car, two copies of our observable universe exist at a distance so far apart it’s impossible to comprehend.
And when we observe celestial objects apparently propelled away from each other at increasing speed, they are not really being pushed or pulled anywhere. It is simply an artifact of trying to keep track of the “same” object in rapidly advancing train cars, while each car doubles in size to contain everything the previous car had, as well as everything new that might emerge from the duplication event. The celestial objects year by year, and indeed ourselves from moment to moment, are never the same thing twice. It’s an illusion brought forth by our brains being born into a cosmic flipbook.
Even something as simple as seeing multicolored pixels on this screen is not real, but the result of virtual “tank engines” moving into the same spatial zones occupied by our retinas, which are themselves constructed of virtual trains of varying size. The reason photons move at a set maximum speed which makes them exempt from experiencing time is because they are all just virtual copies of the real locomotive which is driving the whole train. Every photon in our universe is just a make-believe copy of the very first moment of the big bang. A specter of infinite sameness.
So, objects in our universe aren’t moving apart as much as the space between them is increasing to account for the overhead of a universe with constantly growing entropy and uniqueness. The extra space represents a boundary which limits how far light can travel and affect matter in its realm of influence. If you’re still reading this, somewhere out there, in a part of our universe so far away that light from our known universe will never even remotely reach, there is an opposite you made of antimatter reading the exact same thing as written by an opposite me. But we are only made of matter because of a virtual compression of sameness, so that antiverse may be the exact place where the curvature of the entire universe loops back around and is overlaid upon itself. And the uncertainty of photons may arise from the fact that there are two identical universes overlapped and constantly exchanging probabilities. And this may be the compressive property which allows the fundamental forces to exist in the first place. So, say hi to yourself. You’re the reason you’re here.
Fantastic! I am going to read this many times. Well written, and smart choices.
Im saving this to read again later. Is this your own analogy?
I saw a really good demonstration of this once, but I can’t seem to find a video of it.
Basically imagine a rubber tube with 4 balls equal distance apart from each other.
–0–0–0–0–
If you stretch the tube from both ends all of the balls move an equal distance apart.
----0----0----0----0----
There is no one ball that is the center or the starting point. However if you focus on one ball while stretching it will seem like the others are moving away from it. But in reality they are all moving away from each other at the same rate.
That’s a excellent picture
Everything not gravitationally bound is moving away from everything else. Every single point in space is growing larger. That means that things farther away from you are moving away from you faster then things closer to you. That’s true no matter where in the universe you are.
There’s not really an “away” from the big bang. That’s something science communicators fail to explain - the big bang happened everywhere. Space may have been infinite in size (we don’t know) and it still happened everywhere.
I’d recommend looking up the YouTube channel for FermiLab. They’ve got some excellent videos on the subject.
Thank you so much for the explanation!
I’m going to sound like a total idiot but if our universe was at the center of a ginormous sphere could that give an illusion that every point in space was moving away from another when in fact we could all be falling (getting pulled by gravity) toward whatever edge of the sphere we are closest to?
Kind of a tangent at this point, but there is a very good reason that that couldn’t be the case: according to the shell theorem , nowhere in the interior of a spherical shell of matter experiences any net gravitational force – wherever you are inside the sphere, the forces counteract exactly.
Otherwise, though, the metric expansion of space is different from typical movement, and it isn’t correct to say that things or being pushed or pulled. Rather, the distance between every pair of points in the universe increases over time, with that rate of increase proportional to the points’ distance. Importantly, for very distant points, the distance can increse faster than the speed of light, which would be disallowed by any model which describes the expansion in terms of objects moving in a traditional sense.