The Astronomy Thread

spronk said:

There are more galaxies in the Universe than even Carl Sagan ever imagined

Forget billions and billions. When it comes to the number of galaxies in the Universe, both theorists' and observers' estimates are too low.

bigthink.com

The Universe is a vast place, filled with more galaxies than we’ve ever been able to count, even in just the portion we’ve been able to observe. Some 40 years ago, Carl Sagan taught the world that there were hundreds of billions of stars in the Milky Way alone, and perhaps as many as 100 billion galaxies within the observable Universe. Although he never said it in his famous television series, Cosmos, the phrase “billions and billions” has become synonymous with his name, and also with the number of stars we think of as being inherent to each galaxy, as well as the number of galaxies contained within the visible Universe.

But when it comes to the number of galaxies that are actually out there, we’ve learned a number of important facts that have led us to revise that number upwards, and not just by a little bit. Our most detailed observations of the distant Universe, from the Hubble eXtreme Deep Field, gave us an estimate of 170 billion galaxies. A theoretical calculation from a few years ago — the first to account for galaxies too small, faint, and distant to be seen — put the estimate far higher: at 2 trillion. But even that estimate is too low. There ought to be at least 6 trillion, and perhaps more like 20 trillion, galaxies, if we’re ever able to count them all.

Click to expand...

What a stupid headline. Of course it's written by Ethan Sigel.

He's a smart guy but his clickbaity writing style drives me nuts.

This is going to sound bonkers, but I've come up with a new explanation for E=mc², connecting the idea of "superfluid vacuum theory" / "quantum foam" with classical physics.



Suppose energy is actually a superfluid made up of particles smaller than the Planck length. It fills the cosmos. Like a fish that doesn't know it's swimming in water, we would have no way of directly viewing it even tho it surrounds us. The speed of light then would actually be just the terminal velocity as it passes through the interstellar medium, like the terminal velocity seen in objects being accelerated in systems with fluid friction.



In analogy with a boiling pot of water -- 100°c isn't just the temperature at which water turns from liquid to gas. It's also the speed limit / terminal velocity of individual water molecules as more energy is introduced into the system. No matter how much energy you add, individual molecules can't pass that speed until they reach the membrane at the surface of the pot, where we can view the speed as not just the terminal velocity but also it's escape velocity -- all just different consequences of the cohesive properties of the molecules.



Likewise, then, it becomes easy to visualize that "matter is just energy that's been condensed to a slow vibration" in a new light -- the reason energy appears to have no mass from our perspective is because when it becomes energetic enough to approach the speed of light, it disincorporates into the surrounding medium.... becoming energetic enough to overcome the cohesive forces and gravity acting on it, like our analogous water molecules at the surface of that pot of water. Let's go back to our fish scientist from above -- if water was like most substances and became more dense when it froze, then a fish scientist would believe that ice only has mass up until it melts. From our higher vantage point, we can see that it's really still there, just dissolves into the medium around the fish.



You might think "that's a nice theory but math talks in physics" -- the math is AMAZINGLY simple. It took me a few days to click because it's so simple. I kept trying to connect fluid friction formulas to Einstein's relativity formulas. But really we can just look at the main one.



The energy of a given amount of a boiling fluid can be expressed as it's mass times it's temperature. Temperature can be expressed as velocity. So the total force in our boiling pot of water is just F=mass times the terminal velocity of water squared. Just like the classical physics formula F=mv². So if my theory is correct, we would expect for the energy of light to equal the mass of light.... Times the Speed of Light squared. E=mc² Is just a restatement of F=mv².



Of course even tho any physicist worth his weight in bosons knows that cosmology and quantum physics needs a new conceptual framework to make sense of the experimental results, the last 70 years of dogma will still be hard to shake.



This even gives an explanation for how quantum randomness can lead to apparent determinism at the macro scale,connecting to how the renormalization apparent in the way we express the formulas for different scales of analysis of fluid dynamics allows for random motion of individual molecules to result in classical determinism. The "quantum field" that fills the universe is really just a Planck fluid! The renormalization wouldn't just be a mathematical technique, but an actual factual expression of the way reality works.



Also explains dark matter. Because this allows for things to travel faster than the speed of light as long as they are inside an "air bubble" in the interstellar medium. Like the bubbles at our pot of boiling water that have yet to reach the surface membrane at the top of the pot. We wouldn't be able to see it even if it is there, in a similar way to the way to the way the physics behind sonic booms work. If matter is analogous to a "solid" and energy is analogous to it's "liquid" form, then dark matter would be it's "gas" form... where it's become so energetic that it's even able to overcome gravity and pressure and the etc other forces that act on liquids but not strongly enough on gasses to have much effect.



It also makes you wonder about that escape velocity analogy. Connect the holographic principle in a way and we could even visualize the light molecules launching off orthogonally into a larger 4D space once they reach their escape velocity AND find the surface membrane of our 3D universe, wherever and whatever that is (hesitant to mention this part because I feel it's not as certain, but hey I'm on a roll).



Still doesn't give a great explanation for gravity tho which is still going to be the holy grail of cosmological theories even if I'm right about all this.



I just suck at the more complicated math ever since chemotherapy. Two years later I still have severe chemobrain.



Also explains why space is "cold." Superfluids don't conduct heat, but they do absorb them, if under right? But again this is getting a bit deeper into a specific field than I usually end up. I spread myself too thin studying various different scientific theories instead of focusing on one narrow and specific field like modern academics. Makes it hard to "prove" what I say sadly. If anyone else is better than me at the math please point out any errors in this.