You're welcome. If you want more resources, then take a look at my personal website: www.jasonkendall.com/WPU/AstronomyLectures/07/ Lots of supplementary material for you.

Hopefully soon

Then imagine being there to witness such an event in a ghostly form , a form that would be impervious to any kind of destruction , a form that would be able to witness all wavelengths and slow or speed up time as you wished so you could ride the collapse of the core itself while being able to fully understand the physics involved without in the least being hurt........ WOW ....... All of those neutrinos being released and the rebound off the neutron core in that moment pushing all of that mass and energy away from what's left of the star . Then backing out and witnessing the nebula in all of it's glory as it is bombarded with all of that intense radiation , witnessing through a higher powers eye's the creation of everything that ensues giving birth to new stars with heavier elements spawning solar systems and new life........ , The creation of everything. What a dream !! I can kind of see it in my mind's eye. 😎

Computer simulations of Stellar core collapses have to simulate rally Taylor instability where lighter material mixes with denser material creating chaotic mixing scenarios. The same phenomenon had to be taken into account when doing calculations for implosion systems for nuclear weapons

You got the internet boss. You can literally learn everything for free. Check out MIT OCW

Yep. Get a good telescope and check out some of the stuff he's talking about

Thanks!

Thanks!

Glad you enjoyed it!

Thanks!

Co-sign😁

If you want to see the silly stuff, look here: Television, Radio and Media Appearances kzfaq.info/sun/PLyu4Fovbph6eXnuAq-2oyx8kFMwrzR_At

Actually there is a maximum spin rate to a black hole. Angular momentum is a form of energy and contributes to the curvature of spacetime. And as for inside the event horizon, I Am reminded of Groucho Marx. “Outside of a dog, a man’s best friend is a dog. Inside of a dog, it’s too dark to read. “

@@JasonKendallAstronomer Thank you for the reply and clearing that up. I grew up around Star Trek and everything sci fi. Wished I could have had the smart gene, unfortunately crunching numbers was something I couldn't grasp as a young man. I admire the science community. You don't get the recognition you deserve.

You are welcome. I hope you’ve had a chance to poke around the rest of the channel. I’ve done the whole gamut of into Astro. Left out the planets since I cannot beat NASAs output.

This is known as the Kerr Metric. Gravitational red shift for NS are dominant

yeah I thought something was amiss too

I know. One of the most critical discoveries for physics that should come in the next decade or so will be a well-measured radius is done of say the Crab Pulsar. That will fix in place the equation of state of a neutron star, and give huge amount​ of information about the most extreme objects in the universe.

There’s an upper limit as the energy density rises there would be pair production in the field which would create particles and carry away energy. And this is only one thing.

I’m not really sure. That would be 100% dependent upon the equation of state of a neutron star and its interior. And to do that, a high precision measurement of a neutron star’s mass and diameter is required. But that is currently not possible. So it’ll take some work to do. Ten or so years more maybe.

That's really interesting. First, the universe is likely not old enough for such things to exist. They start off supremely hot, and their surface area is too low to effectively radiate it. But let's assume one exists today. The nature of relativistic effects means that it'll be pretty dark. There would be significant gravitational redshift of emitted light, and it can't get cooler than the background radiation, so the temperature of such an object today is 3K. That means it peaks in the radio part of the spectrum at the surface. The typical gravitational field of a neutron star is large, so that would redshift it down some more. Interestingly, that might make it a photon sink, as it would be cooler than the surroundings thermodynamically, so the photon field would try to "warm it up." That'd leave it actually hotter at the surface than the universe forever, but not by much. So, the thing is pretty dark to begin with. Now if you shine light on an object, the property of reflection depends upon the interaction of that light principally with the electrons made famous by Feynmann's chats on QED. But the electrons in a neutron star that is supercooled to 4K would likely be in a degenerate state. I don't think anyone knows the reflectivity properties of degenerate matter, since we actually can't make that stuff in a lab. So, all I can do is hazard a guess and direct you to graduate-level texts on QED, which I have not read. My guess is that if light is reflected at all under such a state, that old Snell's Law would not apply, and there would have to be some kind of relativistic version of it. My under-informed guess is that such light would be beamed around the circumference in the direction of rotation. Now, such an old neutron star wouldn't be spinning very fast, but I think the end result is that you would not get a reflection back at you (even a reflection to the normal), it would be wildly redshifted, it would be greatly dimmed, would be beamed. That being said, a reflection back to you might occur if you shone the light towards the limb of the star that approaching you as it rotates. So, it's highly likely it'd be dark, unreflective, and would take a staggeringly bright light source just to get a strange reflection back dimly from an odd direction. Also, you'd still not want to be within a lightyear of the thing because of magnetic and gravitational effects. Hm.... Perhaps even that should be taken into account. If the magnetic field stays put, then it's typically quite strong. So, strong that it makes spacetime itself birefringent near the surface. Perhaps wouldn't even get a reflection off the surface, but rather off the bent spacetime due to the intense magnetic field! Fantastic question...

@@JasonKendallAstronomer Wow I didn't expect to get an answer this quick. Thank you so much! I don't think it's possible for it to be transparent since it's surface is still insanely packed with electrons, but I have no idea if it would have a mirror surface or be black or any color. But yeah even if it's mirror smooth the reflection will be very distorted, I didn't think about that. Even the space around it will be distorted and has a gravity lens effect.

@@JasonKendallAstronomer Oh and BTW Thor's hammer isn't made of neutron star material. It's forged with a neutron star's power (probably a few million K or higher). That's the kind of energy you need to melt uru, the magical metal that the hammer is actually made of. Uru maybe very durable and heat resistant, but it's density is in the normal ballpark of metals. The "nobody can lift it" thing is just a magic casted on it. If the hammer thinks you're worthy to wield it, you can lift it. People like Captain America did it in the comics.

Always good to pull in the cultural references, and corrections! Shows you that I'm mostly a DC guy... (Too bad the movies are not as good as the Marvel ones!)

Yes. I’ve been duly corrected on this many times. Frigga and Sif have both mocked me at cocktail parties and Odin won’t return my calls.

I know. I should do a video series on it in astronomy.

Yeah. Why do these lab coated cabals have such a fetish for dying?

Imagine all the people. Living for the space. Hooohooohohoho

Or any flat earth video lmao

Thanks! Please share me around!

x-ray's are light, so, yes, any that are emitted close to the surface will experience it.

@@JasonKendallAstronomer I love neutron stars! Thanks for the great info. So when we see these x-rays from NT's were they red-shifted down from gamma rays? Or are they emitted as x-rays but we view them as UV? Or is the effect just not that significant? Is it correct that some of the emissions are being driven by the magnetic field which extend far from the NT and aren't being red shifted as much?

The contraction has gone as far as physically possible The atoms have been crushed together so that the protons and elections merge together so all that’s left is neutrons packed against each other More mass added will only make more tightly packed neutrons until the neutron star is so massive that it collapses into a black hole

Sychrotron radiation would bleed off energy faster than the mass would accumulate. As the neurton star rotates faster and faster, and gets closer to c, relativistic mass increase comes into play and also removes energy from the system.

That's heavy man! :)

Actually it’s a whole bunch of neutrons (mostly). It’s more akin to an atomic nucleus with a mass number of 10^57.

Yes, but it's not as important as electron degeneracy pressure in white dwarfs. Due to their lower mass, the wavelength of electrons is longer, so quantum effects appear first for them, and dominate the interactions of a highly-compressed, normal-matter gas.

The candela is a base unit for a reason. Do the integral.

probably inside the cores of neutron stars

That's a good question. What I can say is that the current hypothesis and working idea is that as a neutron star forms in the catastrophic last moments of a massive star's life, the core collapses and "freezes in" the core's magnetic field. It's called "magnetic flux conservation". A nice way to visualize it is to think of a classic bar magnet, and its field lines. Any google-able picture will show it. Now take the bar and shrink it, but don't shrink the picture or shape of the field lines. What this means is that the surface area from which the field lines emerge from the magnet will get very small. Therefore, the emerging field lines must get really close together, to allow the "same number of field lines" as was present in the original setup before shrinkage. This is the basic paradigm, but it's still an active area of research, as we can't make conditions like a neutron star anywhere on Earth. Likely it will take knowing quite accurately the radius, mass and polarimetry map of a nearby neutron star, like the Crab, to iron it out. Now, why there is a magnetic field in the first place, is likely because those things just don't dissipate on their own. And you're right, take a ball of neutrons, just as a ball, with no "origin story", and there's no reason a priori for it to have a magnetic field. It's the formation process and subsequent rapid rotation, unknown equation of state, and a high likelihood of wild states of matter that create vigorous interior currents that would then power the field. A couple of researchers go into it nicely here: www.researchgate.net/post/What_is_the_origin_of_the_magnetic_field_of_a_neutron_star

This has puzzled me for a long time since Neutrons are "Neutral" in charge how could they conduct a current. Since we know that a magnetic field is the result of current flow and since there are no electrons in a neutron star how can there be a current flow. How can a magnetic field be generated with out an electric field? When I asked physicists this question I got back silence or an equation that would not fit on a tee shirt. Bill Lewis ex Superconducting Super Collider Laboratory.

@@JasonKendallAstronomer First of all I would like to thank you for taking out the time to answer follow-up question like you did above. Also thank you for presenting an introductory Astrophysics course vs an Astronomy course. Its much more informative. BTW, I am looking for a QCD explanation of what goes on at the core of a neutron star given the current general assumption that some sort of quark/gluon "plasma" exists there. Any chance you could let us know the balances going on in quark degenerate matter?

​@@JasonKendallAstronomerI thought also that the superfluidity of the Interior combined with free electrons in moving around creates the magnetic field

Thats where Magic comes in...

yup. Exactly. Much for the magics.

It’s the fact that they become ultra relativistic, energy is proportional to momentum, and v is indistinguishable from c observationally.

I’d be very interested to see the video of them casually waltzing into a neutron star and blipping on down to the core. If there’s a forge there, one would expect perhaps a nice little mill on the side of a neutron stream. And the bellows could be run by a team of Cheela. Though that would be some oppression.

@@JasonKendallAstronomer to be fair, this is a universe where a guy, completely unprotected, took the full power of a star, all its emissions redirected to one narrow beam, for like 20 seconds. They can still use Hiemdall's teleport beam thing to do the moving though. Still, I prefer to think what he meant is it is made of elements forged in the heart of a dying star. Even if that also includes everything except hydrogen and helium. They just organized them remotely and put the hammer together for the nova to forge it together.

Give her diamonds.

This all seems unlikely. Do you have reference materials that support this idea? Which journal articles support it? Which authors are looking at it? Arxiv references are OK here. In short, while there are issues with the (possible) loss of information at the event horizon, (holographic principle), once things are inside an event horizon, the future of spacetime is "down", as time and space reverse each other. Even pressure itself contributes to curvature. So, once a black hole is formed, whatever goes in is destroyed completely. Please watch my series on Relativity here: jasonkendall.com/Astronomy/03.shtml These topics are always tricky, and it's important to first begin with the current paradigm. Then, find its flaws. These problems are so thorny, that they will, of necessity, defy easy write-ups and definitions. (It's why I stick to the easy bits. They take long enough to communicate.)

@@JasonKendallAstronomer No sir, I don't have reference materials to support this idea. It's just what seems to be what's going on, at least as far as what I can get my own head around. I do understand that these ideas are not part of the current paradigm. But neither was Einstein's idea about being in a free falling elevator, where the occupant would be unable to tell the difference between being in free fall or just floating in space. Ideas don't always fit with our current views. Thought experiments are an essential part of the scientific method. The idea of space and time reversing each other certainly does support the idea of every black hole collapsing into a point or ring singularity. But let's look at why the idea of collapsing into a singularity is thought to be what happens. The cosmic microwave background image or CMB gives us an image that relays a temperature that is so smooth and regular that it is only possible if at the moment of the big bang everything were compressed into a point about the diameter of a single plank length. It follows then that whatever is within the event horizon of any black hole also follows this same pattern. Most if not all of our science surrounding black holes is derived from this premise. However since we also don't observe any other black hole creating big bangs of their own, isn't there something missing in this scenario? What was so special about the big bang that is not true of our run of the mill black holes? The only thing that I can come up with is scope and scale. I.E. the event of the big bang was energetic enough to give rise to all the mass and energy we observe in both the observable universe and what we theorize to be be entire universe. You speak of space and time reversing themselves. Well let's look at that for a moment. Yes without a doubt time dilation occurs in strong gravitational fields. The same is said of objects as they approach the speed of light. And yet when we examine observations of objects approaching the speed of light we see them as if they are slowing down from our perspective. And even though we can't directly observe what happens within the radius of an event horizon the same could be thought to be occurring. When taken to its logical extreme this produces infinite space time curvature, dilations, and collapses everything into a singularity. But we also know that these objects have finite mass, not infinite mass. Since this is true doesn't it follow that it is our maths that are failing to represent reality in these extreme environs rather than the universe conspiring to create singularities that don't follow the same pattern as we calculate were exigent at the big bang? And if we accept that time dilation is not infinite, then time and space reversing themselves is no longer on the table. Take into account also that even though objects, wether in a strong gravitational field(space time curvature) or approaching the speed of light do experience the flow of time differently, the rest of the universe does not. From our perspective these objects seem frozen in time. Or very nearly so. Another issue with thinking of a black hole as having at its core a singularity, is the problem of accounting for the higgs field interaction. We know, or at least think that the higgs field and how particles interact with it give those particles mass. How can this continue if 'nothing' survives below the event horizon? Yes, energy is mass and mass energy and yes they do most certainly simply convert from one form to another. But this doesn't mean that in the absence of particulate matter, I.E. the 'nothing' below the event horizon, that higgs interactions continue. The only evidence that we see is the continued curvature of space time around these objects. We do know that adding energy to an object increases its mass. This has lead to the presumption that energy also produces spacetime curvature. I think it is more fair to say that added energy in an object increases its interaction with the higgs field. But this doesn't indicate that energy itself is itself interacting with the higgs field, only that energy influences matter to more strongly interact. And so if we do not have matter, I.E. the 'nothing' below the event horizon how can energy produce a curvature of spacetime? The short version of this is that any scientific answer that invokes an infinity to describe a finite object must be incomplete in some way. Thus thinking of a mechanism wherein a solid object might produce the effects we see around black holes could open up our understanding of how our universe works in its most extreme environs. It also leads us to the conclusion that the big bang wasn't the beginning of time. That a multiverse is exigent beyond the 96 billion light year diameter we calculate for the universe in which we live. It predicts dark energy, and gives us a mechanism by which a black hole might go nova and thereby create conditions consistent with the big bang. If we look forward in time to the so called heat death of our universe and we presume that the universe is not 'special' then we can imagine that even though matter will eventually degrade entirely into energy that there is also a kind of expanding shock wave flowing into the interversal medium. That the interaction of these shock waves might produce heat spikes that give rise to new matter. And that given the right configuration might collapse down into a black hole that is fed enough mass to eventually go nova and produce its own 'big bang'. This is just how I've come to visualize the overall nature of the universe and how individual 'verses' within a multiverse might be created only to fade into heat death shock waves to eventually repeat the cycle. So not a big bang big crunch style of cyclic behavior but one that much more closely resembles the cycles we see in living ecosystems here on earth.

Ketchup? that’s not very Italian

I'm sure, if you would eat just a bit of neutron pasta, there would be lots of ketchup pretty everywhere. :) Btw thank you for you awesome videos. I need to write it now, because after a while, you'll have thousands of subscribers, and you will not notice my comments anymore in the comment spam.

yeah, I do need to clean this up....

Yeah. I know.... Me speak too fast with coffee excessive..

@@JasonKendallAstronomer Nah I feel you.. as I am.. are just mind blown with the stats of these things and there is no time to or warrant to docus too much into measly m2 or m3 details anyone can see is ok. Also good to make some errors for students to fix to see if they are paying attention. Excellent lecture. Thank you so much. Have a goood one sir. I was sleeping 13 hours and then woke up and chill with big coffee and Gran Turismo and your lecture. Nice first part of the day indeed. 🖖🐺👍

Electrons are ''pushed'' into them causing the charge to become 0.thus turning them into neutrons. Atleast that's what my non-physicist eyes read, i'm sure it's a little more complicated.

Not bad at all.

Yup. I do.

so i have something in common with them. great.

I think you would need to add the mass of mars to notice something. witch is insane

That's a whoops. But, the electrons in a neutron star's magnetic field, can easily approach the speed of light, especially in the extreme field of a magnetar. When it's a situation of electron or neutron degeneracy, then yes, we do have the hard limit of c for the phase space of the electron (or neutron) pressure, which leads to interesting results...

Darn magic gets around things.

Sorry it was a NG TV movie. Here's the link. www.dailymotion.com/video/x65syol

Unless you’re a Cheela.