Let's talk singularities. I've been wondering how valid the theory of a singularity is, and I have a few questions I was wondering about. How can all mass be in one single spot at the same time, that has absolutely no size at all? Wouldn't that mean that the mass was smaller than an atom? Or do the atom's shrink? How does the mass all stay in one piece? I'm probably going to get an answer like "you're looking at it wrong" or something, but if it's really illogical, and doesn't exactly follow currently known physics, then how can I, or anyone else be sure that we understand a singularity? If we can't understand it, how do we know if they do or can exist? If it has no size, how can we see it, much less know it even exists?

It's a hard concept to grasp... I'm normally good at grasping things, so maybe I just never read a well thought out explaination? I always wondered about singularities, I mean hell, they're the center of many theories such as the big bang theory.

I'm opening this topic for anyone else who has questions or answers regarding this subject.

That's a good question. I'm no expert, so my I'm just giving thoughts, not actually backed theory (if I'm wrong feel free to smite). First of all, a singularity is kind of like a point on an x-y-z graph. It's certainly on the graph, but it doesn't take up any space. As for atoms "shrinking" atoms are mostly vacuum, so... I think that if some force was strong enough to pull all the mass of an atoms together, it could occupy a very small space. Now as for what force does this.... that's a fine question. I'd suppose that it's some force that works on quarks, or maybe even smaller particles than quarks, and it's very very strong, but has some degree of unstableness.

The theory in this case is general relativity, Einstein's theory of gravitation. And singularities essentially amount to divide by 0 errors. You're probably aware that general relativity describes spacetime in terms of geometry. But there are instances where the equations describing that geometry blow up. The first solution to Einstein's equations is called the Schwarzschild metric and it had two cases where you'd be dividing by zero: one where r = 0 and one where r = 2Gm. The second one turned out to be what's called a coordinate singularity--changing coordinates made it go away. The second one, however, is a real singularity, meaning something is really going on there (this is the point at the center of a spherical, nonrotating black hole).

You obviously know the physical interpretation. Mass is crushed to an infinitely dense point at the center of the Schwarzschild black hole. How valid is that? Maybe valid. Maybe not so valid. This is a very, very extreme physical situation and its tough to ask any one physical theory to account for every situation, no matter how extreme. Every theory has limits to its validity, where a more accurate theory takes over to clear things up. But maybe this crazy state of affairs is real.



In our daily lives we do associate with mass with size, it seems. But the Standard Model of particle physics, for example, treats elementary particles are being points. The top quark, which has about the same mass as a gold atom, and the electron are both considered to have the same size--no size at all. So the size-mass issue isn't necessarily a big problem (though it might take some getting used used to). But I imagine you're asking what's going on physically. Let's take a quick look at what comes before.

Stars exist in a state of hydrostatic equilibrium: gravity tries to pull them inward and the pressure from the temperatures generated by their fuel-burning counteracts this. But gravity is patient and eventually the nuclear fuel will run out. At that point complex things start to happen but the end result is gravity has (near) free reign. If the mass (and thus the gravity) isn't large enough, then a principle that keeps electrons and neutrons from being in the same place at the same time (Pauli's exclusion principle) will generate a sort of pressure--called degeneracy pressure--to halt the collapse. For smaller masses, electron degeneracy pressure holds them up and they become white dwarfs but for larger masses a stronger force is needed: neutron degeneracy pressure. But neutron stars can't be arbitrarily large. There's an upper limit (the Tolman-Oppenheimer-Volkoff limit) above which pressure from the neutrons can't halt the gravitational collapse. In that case (in general relativity's mind, at least) nothing can stop the collapse and it goes into a sort of freefall, smashing ever smaller and smaller until it gets as small as you can imagine.

Now it's very possible something else goes on to stop it eventually. This is a physical situation where our understanding of the underlying physics is hazy at best. We're not sure what works and what doesn't in such situations.



Yes, the singularity would be smaller than an atom because atoms have a size. Everything would be smashed far beyond having any structure (i.e. atoms).

Some Theories of Physics (superstring or M-Theory is an example) try to limit the smallness of things. In these theories the smallest size anything can attain is limited to the Planck length (if I am remembering this correctly) and so they do away with the idea of a zero-size singularity. As the strings themselves are two-dimensional 'objects' in our universe, any amount of them may occupy a three dimensional space such as the centre of a black hole. This accounts for the tremendous mass these 'singularities' may have.


I'll reread the books I have on this to ensure I've recalled the details correctly.

That's where I don't understand the logic. If it has "no size at all", how can we physically see it?



So, in other words the atoms would be shrunken as well? Because if not, I was wondering what the hell, lol. Mass that is suppose to be made of atoms, smaller than atoms.


Alot of it seems illogical.

Seeing things doesn't have much to do with their size. Physically seeing something is just a mode of interaction. There are four ways in the universe for things to interact, all via what we usually call forces. Sight is a form of electromagnetic interaction between the electrons in the pigment in your eye and whatever you're observing. What that means is that only particles that "couple" with the electromagnetic field (i.e. have an electric charge) can trade photons with your eyes. Everything you see you see because the electrons in its atoms deal in photons. This photon-swapping, however, doesn't indicate that the charged particles involved have some particular size.



Atoms would be torn apart into their constituent pieces and thus wouldn't be atoms anymore. The matter would be broken down to basics and wouldn't have structure (and thus size) anymore.

But the smaller something is, the harder it is to see, hell some things can't be seen. If something has NO size what-so-ever, doesn't that mean it takes no area in space at all, so how are we to SEE it?

What you're talking about is an issue of resolution. It takes only a handful of individual photons to stimulate the light receptors in your eye but you can't "see" (by that I mean resolve) a few electrons or atoms; you experience only a flash of light. In reality, that's all that ever happens. Your brain does a wonderful job of constructing images from these flashes of light--the more photons, the easier a job the brain has of doing it. You see different shapes and different colors; you've got rods and cones to deal with light/dark contrasts and colors, as well as specialized neurons that deal with different patterns. But you never really see individual atoms. You just make sense of all the light that's streaming into your eye. The whole process is just as much about memory as it is about what you're actually seeing. Newborns seem uninterested in their surroundings, not because their retinas aren't fully developed but because their brains don't assign the same meaning to what they're seeing as yours does. That takes time and experience in the form of memories. The physics here gives way a little to neuroscience.

Why not spend time on things that really need research?

Are you talking to the original poster?

I guess to everyone. It just seems to me that it is less necessary to waste time on these things than to solve the other problems that plague us (humanity), such as energy and food. It'd also be nice to get all the governments back under people control. Once we've solved the real problems, we can fiddle with singularities all we want.

Not that I necessarily agree but it's not as if we can't multitask. The very same guy who did some of the pioneering research into black holes and singularities led the project that unleashed nuclear energy on the world (destructive in that case, granted).

Something that is generally misunderstood is multitasking. In any computer, multitasking is the suspension of one operation to devote time to the next. They don't all happen at once.
The same is true for human logic.
Frankly, I have little faith in academia, for various reasons. Such as the school that obtained a grant to research the feasibility of using monarch butterflies as an alternate food source. Jeez, they've got to be kidding! We spend time and money on such bs as this?
It is simply that I feel we should solve more pressing challenges first. To clarify, I have no problem with research into valid and reasonable subjects, since there are many areas we think we know but do not; those, I challenge both private and academic institutions and individuals to research. Other areas appear to me to be nonsensical or whimsical, and being an engineer and so devoted to practicality, I maintain those areas should temporarily be abandoned, to be returned to active status later.
I also maintain, as I do in our political institution, that those things we call laws should be revisited, at least from time to time, with the question in mind as to the validity of such laws. As with the US Code, I feel that each legality should be questioned, and revised or revoked if it is not applicable or if there is question of its validity.

And one of those, I assume, is general relativity (to maintain some logical connection to the content in this thread)?

That's a bit of a stretch, isn't it?
You know well what I'm saying, and shame for bringing a perspective such as the above. I know you're above that.
It is reasonable to find bugs and plants in the Amazon; it is reasonable to dig out skeletons and cities long dead; it is reasonable to investigate various theoretical possibilities; it is not reasonable to use valuable resources to investigate butterflies as a food source.
It is reasonable to do this kind of research: build and test something like a Faraday wheel, to determine if and why there seems to be no back forces when the wheel generates power. Why waste a bunch of money on silly stuff when there are so many items lacking explanation?

No. I'm not.

This isn't a thread on politics or the proper allocation of research dollars, it's a thread on singularities that you're hijacking for some reason. If you want to start another thread to go into whatever you're getting at, that's fine. There's a very interesting discussion to be had there. But that's not appropriate for this thread.

Not trying to hijack the thread. Just trying to get a reasonable answer...
Since that's not forthcoming, I'll just go off to my shop and do some more experiments with ZPE. At least I think that's useful.