Dark Matter Stars May Have Seeded Supermassive Black Holes

We're getting very theoretical here, considering we're not even sure what dark matter is. Anyway, in the early universe, when all the matter was squished together a lot more tightly than it is today, stars that formed were often a little different. Oh sure, they were made of hydrogen, but they also contained a bit of dark matter in the form of Weakly Interacting Massive Particles.

These dark matter stars would have looked a lot different than the stars we know today. For one, they were gigantic, spanning up to 10 AU across. They could be millions of times heavier than the sun, and billions of times as bright.

The existence of these stars could solve a big mystery of the early universe. Galaxies seemed to form around supermassive black holes, but where did these black holes come from. A gigantic star would collapse into a gigantic black hole. It's almost a little too obvious.

Computer Simulates The Universe A Little Too Well

So I've been very busy this week but I wanted to make some sort of post. So here's an article about an AI simulating the universe so well that the scientists behind the simulation aren't actually sure how it works. Which is cool and a little disconcerting.

What Will Stars Look Like in the Distant Future?

I'm talking billions, trillions of years, maybe even more. It's a somewhat sobering reality that nearly all of the stars that will be born during the lifetime of the universe have already been made. Now, stars as we know them will continue being made for billions of years, far beyond the life of humanity. But in the far-flung future, different types of stars will begin to pop up, stars that haven't had enough time to develop yet. Here's a list of four of those hypothetical future stars:

This won't do you much good here.

1. Blue dwarf. They're simple enough, they're the final phase of evolution of red dwarfs, the smallest type of star. Instead of expanding into a red giant like the Sun will when it starts fusing helium, they'll get smaller and much hotter, turning blue. However, their ultimate fate will be the same, eventually turning into white dwarfs.

2. Black dwarf. Hey, speaking of white dwarfs, this is what will happen to those after billions of years and they've cooled off. To call it a star is a bit generous, a black dwarf will be a planet-sized lump of super-dense matter generating little, if any, light.

3. Frozen star. Here's where things start to get strange. Eventually, the universe will run low on hydrogen and helium, but stars of a sort will continue to form, fusing paltry scraps of hydrogen in among icy clouds. These stars would struggle to get past the melting point of water, and would resemble giant brown dwarfs rather than actual stars.

4. Iron star. Now we're into real hypothetical territory here. As the universe slowly expands to infinity, undergoing heat death, there will be a lot of iron floating around. Iron is both extremely stable and if you know your fusion, you'll know that once you start fusing iron, more energy is used to make the reaction than is put out. That's what causes supernovae. However, and providing protons don't decay, when a bunch of iron clumps together to form a body, quantum shenanigans will cause an ignition of sorts, splitting the atoms and forming an iron star.

Is Cosmic Inflation Theory Wrong?

Sometimes, even fairly basic scientific concepts get questioned. This is a good thing. If there's enough room in a theory for questioning, there's a good chance the theory is either wrong or incomplete. Take the Big Bang. It's a fairly uncontroversial theory in the scientific community. All the matter in the universe started from one single point, it explodes, and we get the universe. But there was a problem with that concept. The universe is flat, as in, the matter is spread out incredibly thin and space is basically empty. That's fine as far as it goes, but there was no way the Big Bang could have been powerful enough on its own to spread the matter of universe so thin. There must have been another factor, and into the breach came inflation. This inflationary energy is what cause the universe to become what we see today.

Of course, a theory is nothing without evidence, and we have significant evidence of inflation. There are the ripples in the cosmic background radiation, the existence of dark matter (though we still don't know what dark matter is), as well as another type of gravitational radiation called B-Mode polarization, found in 2013 using data collected from the Planck satellite. Case closed, right?

You know where this is going. Three scientists took issue with the Planck data, saying that it fit the most convenient theory of inflation, not the simplest one. And that leads into one of inflation's biggest problem. It is so broad a theory, with so many hypotheses contained within it, that all new data can be made to fit. Nothing can disprove it. And that's a problem. If it can't be disproved, it's not science, it's philosophy. And we're not dealing with a bunch of philosophers here, we're dealing with physicists. And pro-inflation physicists (the vast majority, let's remember) are not happy with this suggestion. They say they need more time and more data, that it's just taking a very long time to eliminate hypotheses. The anti-inflation physicists say that more than enough time has been spent on inflation, nothing will prove it, and new data will just cause the theory to stretch even further.

Inflation has another big problem, and that is inflation seems to require a multiverse. And once again, the existence of multiple universes would be impossible to prove and is therefore not science.

That begs a question, though. If inflation is wrong, how did the universe get the way it is today? The anti-inflation physicists suggest something called "the Big Bounce", a process wherein the universe grows out of a point, reaches a certain point, then collapses back on itself, only to repeat the process again and again. This is also not a new idea, and like inflation, it has a big problem. The Big Bounce has always required the existence of naked singularities. And once a theory requires naked singularities, it's done. Nobody likes naked singularities. Our intrepid trio anti-inflation physicists claim they've managed to figure out a Big Bounce theory without a singularity, but that claim's been made before, and has always been disproved.

So where does that leave us, the non-physicist audience? Well, if you want to be democratic about it, inflation has the support of almost everyone, while anti-inflation is thought of as being pretty fringe science. I'd say if you're ever at a party, and someone asks about your opinion on the formation of the early universe, just say inflation. It would require less explanation.

There Are A Lot More Galaxies Out There Than We Thought

About ten times more, to be more specific. And to be even more specific, somewhere around one or two trillion, compared to the 100-200 billion galaxies we previously thought was the total.

Now, to be fair, we haven't actually seen any of these new galaxies yet. Our telescopes aren't powerful enough to. But because of math, we know they should be out there. Otherwise, the numbers don't work out. I don't have a whole lot to say about this, other than "Cool, 10 times more galaxies." I mean, greater understanding of our universe is important, and obviously, this is something newsworthy, but basically, what this boils down to is "Gee, you know how the universe is just enormous? Well now it's even enormouser!" Yeah, spellcheck, I know that's not a word. Maybe I'll be a little more interested when we can actually see these new (very, very old) galaxies.

Advanced Astrophysics is Kind of Difficult

A few months back, scientists announced they had found gravitational waves from the very beginning of the universe, lending credible evidence to the theory that the universe expanded at an enormous rate in the first few... what's the small prefix I can think of...picoseconds.  Anyway, in those first few instants, the universe expanded at much faster than the speed of light, or so the theory goes.

As I've mentioned before, science is hard, and this kind of science is really hard.  An extraordinary claim was made here, and you know what they say about those.  Of course, equally important is making sure you didn't make any silly mistakes, like not compensating for dust floating around the Milky Way.  Now, no one is saying the observation is wrong, or that the whole theory is wrong.  Unlike propulsion from nothing, this actually has a chance of working out.  I hope it does.

In an unrelated bit of news, I'm putting the link to my Twitter back on the bottom of each post.  I'm going to try and actually be an active Twitter user...er, even if I don't care for it.  Just don't expect too much.

My Twitter

Multiverse Theory Could Be Wrong

The universe might not recognize the size difference between this...

The field of particle physics is at a standstill.  The problem, in a nutshell, is this: the particles we all know are very light, but physicists predict that there are unknown particles associated with gravity that are much heavier.  About a billion billion times heavier.  This isn't right, especially in this field.  The Higgs Boson, the particle that is surmised to give all other particles mass, should be heavier because of these Planck mass particles, and should also drag the weight of standard particles up as well.  But this isn't the case. 

To get around this problem, scientists came up with supersymmetry, the idea being that every particle has a slightly heavier twin, and when a Higgs boson meets a pair, the masses cancel out, and the Higgs stays light.  Supersymmetry isn't working either, unfortunately.  Scientists have yet to find a partner particle, and it's been decades since they were first theorized.  Because supersymmetry seems to be a dead end, scientists have all but given up on it, which has given credence to the multiverse theory.  Why?  Because the observed properties of the Higgs are so improbable that the universe we observe must not be the only one.  There must be other universes with Higgs bosons with different properties, properties that don't give atoms the ability to form.  Not the multiverse idea most people have, but a bleak, empty multiverse that seems to elude understanding.  This isn't what scientists want to hear.

...and this.

There are new theories in the works, but they are still in the early stages.  Most of them focus around scale symmetry, which, if anything, is even weirder than everything I've just talked about.  The idea is that the universe fundamentally lacks scale, and that the universe doesn't know the concept of mass or length.  This article was a challenge to read, and this part is where it really gets tough to understand.  I guess all the average person needs to know is that it could fix the Higgs problem, and it gets rid of the multiverse theory.  We'll have to see where that takes us, but really, there doesn't seem to be any other direction for physicists to take.