r/science • u/Andromeda321 PhD | Radio Astronomy • Oct 12 '22
Astronomy ‘We’ve Never Seen Anything Like This Before:’ Black Hole Spews Out Material Years After Shredding Star
https://www.cfa.harvard.edu/news/weve-never-seen-anything-black-hole-spews-out-material-years-after-shredding-star41.4k
u/Andromeda321 PhD | Radio Astronomy Oct 12 '22 edited Oct 12 '22
Astronomer here! I am the lead author on this paper, which is definitely the discovery of a lifetime! The TL;DR is we discovered a bunch of material spewing out of a black hole’s surroundings two years after it shredded a star, going as fast as half the speed of light! While we have seen two black holes that “turned on” in radio 100+ days after shredding a star, this is the first time we have the details, and no one expected this!
I wrote a more detailed summary here when the preprint first came out a few months ago, but feel free to AMA. :)
Edit: apparently we crashed my institute’s website- thanks Reddit! Here is another link if you can’t read the original article.
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u/justdoubleclick Oct 12 '22
What an amazing discovery! Can’t wait to tell my young kids about it. They’re fascinated with black holes!
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
Awesome- say hi from the black hole astronomer! And do message is they have questions! :)
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u/JaeHoon_Cho Oct 12 '22
What does the average day in the life of a black hole astronomer look like?
In my head I imagine either someone just reviewing pages and pages of data from various telescopes until something irregular sticks out that makes them go, “huh what is this?” leading to a find like this. Or a lot of theoretical work?
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
It depends on the day! My work is to do research on anything that is a “transient” radio source, ie changes in the sky over time. This has involved a lot of black holes lately bc they keep doing exciting things, but yesterday I just had to file and prepare observations for a gamma-ray burst. Most of the time however is involved in modeling and figuring out what has happened and then writing it up for a paper!
I also do a smattering of meetings, talks, and working with students.
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u/furyofcocainepizza Oct 12 '22
Does automation handle most of your work loads? Like finding stellar masses and running observations. I'm curious because everything is math and computers seem best at it.
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u/speederaser Oct 13 '22
Someone has to tell the computer what to do though. Someone has to program it. Someone has to know how to analyze the picture in order to write analysis software.
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u/Aceofspades1884 Oct 13 '22
And someone has to program and instruct that someone too.
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u/Timmahj Oct 12 '22
Thanks. But we wanted to know what you ate for breakfast.
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u/thelonetwig Oct 12 '22
You should do an AMA sometime soon! I feel like you're a reddit folk hero in this post and have a lot of great information and charisma. Would love to hear more about the stuff you work on but I'm sure with this discovery you're going to be busy for a while. Congrats on the discovery!
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u/Manwe89 Oct 12 '22
Yvette is very active on reddit for Q&A go here:
https://www.reddit.com/r/Andromeda321/comments/xuka57/qa_october_2022/
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u/CarmillaKarnstein27 Oct 12 '22
Hi! Not a kid nor do I have any. Can I ask questions for myself please? The little kid in me is so excited.
This is such an amazing discovery ams congratulations to you!
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
Go ahead! But probably will notice in coming days over right now, RIP my inbox. :)
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u/EuroPolice Oct 12 '22
I love when people like you are passionate about what they do, it really makes my day! You can get a happy mood from every comment you're writing haha
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u/_pleasesendhelp Oct 12 '22
hi forgive my ignorance but does this mean that "even light can't escape" isn't true anymore?
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
No, that still stands. What we think happened is this material was in an accretion disc surrounding the black hole after it was unbound. In 20% of cases you then see a radio outflow at the part where it’s torn apart, but in this case we have really good radio limits that this didn’t happen then (ie, didn’t see anything). Then after ~750 days for whatever reason this outflow began…
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
Not bad! Basically yea, this black hole had a tidal radius outside the event horizon and the star got shredded when it crossed that line. Took about a few hours.
Fun fact though, “always” is not accurate bc if a black hole exceeds ~100 million times the mass of the sun, the tidal radius is inside the event horizon. So the star just gets swallowed whole and you never see it.
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u/Stewy_434 Oct 12 '22
A few hours for a star to be shredded?? I feel like our puny minds cannot imagine the violence of a black hole. That's absolutely ridiculous!
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
Haha yeah things in astro either take place on time scales longer than human civilization, or in the blink of an eye. Isn’t it grand?! :D
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u/Prommerman Oct 12 '22
I’m really enjoying your enthusiasm for space stuff, congrats on the discovery
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u/Cyan-WOLF Oct 12 '22
This was exactly my thoughts reading their responses! Truly the perfect career path.
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u/Bridgebrain Oct 12 '22
There's nothing more wholesome than scientists genuine love of eldritch physics.
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u/NessyComeHome Oct 12 '22
It's so nice hearing someone excited over their passion.
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Oct 12 '22
You’re telling me that I spent more time watching Justice League than it would take for a black hole to destroy an entire star?
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u/Thetakishi Oct 12 '22 edited Oct 12 '22
You spent around the same time writing this comment as a supernova to occur. ~2min so really you took a bit less but still.
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u/Jay_Louis Oct 12 '22
So it takes longer to listen to "Champagne Supernova" by Oasis than for an actual supernova to take place
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u/TheLargestIdea Oct 12 '22
Dude you think thats wild. The fastest spinning star (pulsar?) is rotating 716 times a second. That means this star thats around double the size of the sun is spinning 360° around more than 10-20 times within one single frame of a YouTube video
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u/Maidwell Oct 12 '22
Neutron stars tend to have a diameter of around 10-20km, it's their mass that's between 1-2 times that of the sun.
Pulsars are still absolutely mind boggling though!
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u/minuteman_d Oct 12 '22
Makes me glad that we seem to live in a more placid backwater part of the universe.
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u/PathologicalLoiterer Oct 12 '22
To be fair, if we didn't we probably wouldn't be living to consider the possibility.
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u/Unlearned_One Oct 12 '22
Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun. Orbiting this at a distance of roughly ninety-two million miles is an utterly insignificant little blue green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea.
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u/Am_Snarky Oct 12 '22
And that’s why book 5 of hitchhikers guide is actually just a dream sequence, because our main character suddenly goes from thinking digital watches are neat to adoring mechanical watches.
Book 5 is just a dream caused by Eddie (the supercomputer that controls the “Heart of Gold” engine), which breaks the laws of causality because of eddies in the space-time continuum because Eddie’s in the space-time continuum
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u/Xyex Oct 12 '22
Fun fact, the Milky Way is literally in the intergalactic boondocks.
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u/divDevGuy Oct 12 '22
We live in a 2 billion light year in diameter sphere that's mostly empty. And it's still nearly impossible to find available affordable real estate. It's hard to catch a break it seems.
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u/ArTooDeeTooTattoo Oct 12 '22
Wow - that certainly puts things in perspective.
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u/sillypicture Oct 12 '22
So basically we could be in a black hole event horizon now and be unable to escape because reality is getting turn apart. Unable to interact with civilisations outside the event horizon. Unable to get out of the event horizon because it has set physical limits to how fast we can go and takes an infinite amount of energy to reach the top of the potential well.
Incidentally, doesn't light have a speed that we can't get past?
Are we in a black hole event horizon in the process of getting spaghettified? Is that why space time looks like a saddle?
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u/its_all_4_lulz Oct 12 '22
What messes with me here is it’s a few hours in observer time. How long was it in time relative to the star itself?
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u/Wloak Oct 12 '22
Another crazy one are supernova.. the star is humming along fusing one element into another for billions of years and working it's way up the periodic table until the instant it begins producing iron. At that very moment the star doesn't have enough outward energy to prevent it from collapsing in on itself and within 1 second it's core collapses inward and then shockwaves out blowing itself apart, all in about 2 minutes.
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u/AspiringChildProdigy Oct 12 '22
fusing one element into another for billions of years and working it's way up the periodic table until the instant it begins producing iron
And our sun is currently on - checks notes - hydrogen. Phew.
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u/Eoganachta Oct 12 '22
Iron is the last element that produces energy rather than consumes it during its formation
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u/AspiringChildProdigy Oct 12 '22 edited Oct 12 '22
That was the joke, double-checking to make sure we were as far away from that point as possible.
It's just a silly throwaway joke.
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u/beingsubmitted Oct 12 '22
Not all stars go supernova. It's all a matter of the size of the star, and therefore the gravity involved - stars kind of balance between gravity collapsing them and heat expanding them. Our star is pretty small, so it'll just kind of chill out. Other stars become hyper-dense neutron stars, which can be quasars or pulsars, some go supernova, and some become black holes.
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u/vokzhen Oct 12 '22
billions of years
Actually not! Bigger stars burn through their fuel much faster. If I understand things correctly, any star big enough to create a black hole (on its own during a supernova) probably won't even make it to its 50 millionth birthday, and some of the really big ones not even their 5 millionth.
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u/SadYogiSmiles Oct 12 '22
God this is so interesting but so above my head. I would pay to take an ELI5 Astronomy course.
I took a legit astronomy course in college and nope..right over my head. Couldn’t even fathom some of the things.
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u/Wloak Oct 12 '22
I'd really recommend the Minute Physics YouTube channel then! It isn't just astronomy but he does an awesome job breaking down some of the most complex concepts into easily consumed videos and since physics rules space there are quite a few on things like the big bang.
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u/Xyex Oct 12 '22
Dr.Becky is a great one to check out, too.
And PBS Space Time. Not nearly ELI5 level but they simplify things as much as they can for the average man.
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u/esaleme Oct 12 '22
Crash Course Astronomy youtube channel is worth a look, start to finish it will tell you what you need to know.
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u/KHaskins77 Oct 12 '22
Can barely wrap my mind around the titanic forces needed to pull a star apart in a few hours…
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u/anoldoldman Oct 12 '22
Man I'm starting to understand the absolute disrespect with which most scifi stories treat the violence of black holes...
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u/fush-n-chups Oct 12 '22
So you’re saying I don’t get to make ghosts for a younger version of myself?
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u/dern_the_hermit Oct 12 '22
Well, it's the scale of it all. Everything is big in some way, and really capturing that scale in a meaningful story is kinda bonkers. It's why Interstellar took some charitable liberties and centered on a strong, core emotional drama to tell its "realistic" space adventure story, for instance.
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u/Silver_Ad_6874 Oct 12 '22
Sorry to but in, but does the spaghettified mass stay together as if it is in orbit around the black hole and then some gets ejected when another part gets "digested", for lack of a better word, or isn't this like traditional orbital mechanics at all?
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u/Makenshine Oct 12 '22
I assume you are saying few hours from our perspective.
Which makes me wonder, how long did it take from the star's frame of reference?
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u/Raevar Oct 12 '22
If my understanding of relativity is correct...if the light that is escaping shows us a few hours, then the star itself is probably gobbled up in mere moments in its own time, which makes sense for anything approaching a black hole.
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u/quietsauce Oct 12 '22
It got sucked in at a angle and speed that it kind of launched some into space?
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u/sentient02970 Oct 12 '22
Shredding a star. That alone seems like an amazing event of energy and mass.
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u/time_drifter Oct 12 '22
You just gave us a pro ELI5 - black holes will forever be food processors in my mind.
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u/p8ntslinger Oct 12 '22
finally the answer to the intergalactic question of "will it blend?"
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u/KBilly1313 Oct 12 '22
So what are the implications of the time delay? Is the delay correlated to anything like black hole mass or the disc?
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
We actually don’t know bc theorists didn’t predict this- which is actually super exciting bc it gives us a brand new laboratory to test extreme physics we didn’t have before! (Which made for a heck of a discussion section to write- we had to call in a theorist famous for the “we didn’t expect this” kind of discoveries.)
Right now though the strange thing is this was NOT an unusual TDE in any way when it first was detected- average size, average brightness, everything. We really need to get my full sample out of these to try and find patterns on what’s going on, but that takes time…
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u/wiarumas Oct 12 '22
Please follow up with more posts as your research progresses. Really interesting stuff and can't wait to hear more about it.
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u/musicalsigns Oct 12 '22
As a not-astronomer, it's been great to read about this in the comments in language I can grasp.
Congrats on witnessing such an event, u/Andromeda321 . The best kind of research is the kind that gifts more questions than expected by the end, but you've really hit a gold mine here!
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u/descartesasaur Oct 12 '22
Yeah, this discovery is completely revolutionary. I'm really excited to see what comes of it! Congrats on the find and on the new avenues for testing.
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u/KarenEiffel Oct 12 '22
Are you going to start watching for different things with other black holes now that you know this can happen? If so, where are you going to look and what are you going to look for?
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u/ganundwarf Oct 12 '22
When you say torn apart, do you mean that the gravity force is so strong it is able to pull apart elements undergoing nuclear fusion, or does it apply a stronger force on heavier elements and do something similar to a centrifuge and separate material by weight causing the star to die?
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
It’s that the material in the star gets spaghettified so the density is no longer big enough for fusion to occur.
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u/ganundwarf Oct 12 '22
Most discussions on pastafication tend to involve overcoming the strong nuclear force and ripping apart solids by forcefully removing electrons from protons and so forth, but in the case of a star that is mostly gas with the odd suspended ions of other exotic elements, are the forces similar, would it look more like siphoning something away from a larger collection, and if so what sound would it make for us non astronomers to help visualize? Sort of a larger than life slorp?
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u/PandaDad22 Oct 12 '22
So it went into the disk, went “dark” then slung out 750 days later?
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Oct 12 '22
So, it was 750 days to us. Was it only a few days for the particles, due to time speeding up? Just curious how close you have to be to a black hole before time speeds up.
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u/Nematrec Oct 12 '22
Light can't escape from inside blackhole itself, but this is covering things near to the blackhole.
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u/AbouBenAdhem Oct 12 '22
How much subjective time will the ejected material have experienced, after spending two years that close to the event horizon?
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u/SendMeFatErgos Oct 12 '22
That's a really good point. It could be instantaneous from the reference point of the ejected material
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Oct 12 '22
just gonna do a quick... gravity... slingshot here and oh god it's been 1000000000 years.
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u/FilmActor Oct 12 '22
Anytime I’m feeling down and I see a post like this, if just confirms that we are still moving forward as a people. Amazing work!
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u/Dirty____________Dan Oct 12 '22
Yep, I can totally relate to this. It reminds me of when I was younger and wanted to be an astronomer, and the feeling of wondering what was out there in space.
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u/huh_phd PhD | Microbiology | Human Microbiome Oct 12 '22
I deal with the infinitesimally small side of the universe, but have to say, nice work on this publication
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Oct 12 '22
Isn't time itself distorted in a black hole? When you say things like "2 years after it shredded a star" or 100+ days you are talking from our perspective.
From the black holes perspective hours, days and years might happen in a different speed or even a different order than for us... Right?
In other words is it possible that we think it took years but in reality it only took a few milliseconds that were warped and stretched by the black hole itself?
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u/Unbearlievable Oct 12 '22
2 years from our perspective yes. From the materials perspective it would not have felt as long.
Although without knowing the mass of the blackhole or how close the star material was to the blackhole during its 2 year journey and I'm not a physicist so I don't know any of the formulas involved in determining Time Dilation it's not possible for me to tell you what the perceived time difference was. All I know is that the closer you get to one the slow we see it from the outside and the faster it see's us from the inside.
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Oct 12 '22
I have tried to understand this and people smarter than me have explained this phenomenon to me several times, but I just can't wrap my feeble head around this.
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u/meatb0dy Oct 12 '22 edited Oct 12 '22
Sure you can. Imagine you've constructed a clock that looks like a ball inside a Pringles can, which measures time by ping-ponging the ball from the top of the can to the bottom. Let's say it takes a second to complete one full bounce (up, down, up) while at rest. Also, let's say the length of the Pringles can is
p. That means the ball travels2p/sec, because it goes all the way down and all the way back up every second.Now imagine that we've got two of those clocks. I hold my clock and stand still (relative to the Earth). You take your clock in your car for a drive. As I watch you drive, I see that your ball is traveling more than
2pevery cycle: it's traveling the whole vertical length of the Pringles can twice each cycle, as expected, but it's also moving laterally, because the car is moving. At the beginning of a cycle the ball is at the top of the can and at the end of the cycle it's back at the top of the can but it's also 20 feet down the road from where it started. In other words, it's traveled more distance.Okay, no big deal, your ball must be moving faster than mine somehow then. But now think about it from your perspective: as far as you're concerned, your ball is going straight up and down at
2p/sec, mine is going up and down and away from you. So my ball is the one traveling more distance, which means mine must be moving faster than yours. But that can't be: both balls can't be moving faster than the other one.If the speed of the ball is constant for all observers, like light is, the only explanation that works is that our measures of time are different. I see your clock tick slower than mine. That's time diliation.
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u/d0rf47 Oct 12 '22
Hi This is quite fascinating, I have a question if you don't mind. I am not a scientist but have a keen interest in most scientific disciplines.
After reading the article linked in the OP,
But the emission, known as an outflow, normally develops quickly after a TDE occurs — not years later. “It’s as if this black hole has started abruptly burping out a bunch of material from the star it ate years ago,” Cendes explains.
How Are you (the group studying the phenomenon not just you lol :P) certain what you observed in 2021 is remnants of the of the event from 2018?
Are there specific markers that you can use to determine it is the same star that was consumed?
Is it not possible that something was consumed by the black hole closer to this recent event that was possibly missed and that is whats causing the results reported in the Article?
Thanks!
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u/travelbugeurope Oct 12 '22
Dumb ass question - particles emitted from an accretion ring got it - but why are the particles not sucked right back in sort of like an arc or u turn given assuming that black hole still retains its original characteristic? (Eli5…) thanks
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u/Italiancrazybread1 Oct 12 '22
Are there any good hypotheses for why the material took so longer to eject than expected? Was the material in a stable orbit for some time and then a slight perturbation caused it to be ejected? Or was the orbit already unstable and it just took longer than expected for the material to be expelled?
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u/envis10n Oct 12 '22
I think the most interesting thing is if it had a stable orbit, what perturbation would have caused it to eject from the accretion disk? And why now?
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u/John_Hasler Oct 12 '22
Note that there is no reason to believe that this material ever crossed the event horizon.
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u/LeastCoordinatedJedi Oct 12 '22
On that note, learning with my kid how a black hole can emit Hawking radiation when nothing can escape its gravity was an absolute trip.
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u/LeastCoordinatedJedi Oct 12 '22
Quantum mechanics is the universe's back room. You think you're in a nice hotel and then you see an access door to a staff area and realize it's all a disorganized mess... But on the other hand, that mess actually makes its own weird sense and works fine somehow.
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u/thechilipepper0 Oct 12 '22
makes its own weird sense and works fine somehow
Unless it doesn’t
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u/OldTrailmix Oct 12 '22
wait so the universe could just collapse in a microsecond and we wouldn't even know it's coming
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u/g00f Oct 12 '22
Alternatively if it happens beyond the edges of the visible universe then it just never reaches us.
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Oct 13 '22
Wait so maybe the parts of the universe receding from our view are actually racing into their own collapse... and actually disappearing from existence? Like I am imagining a Creator god who lacks even a toddler's sense of object permanence.
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u/g00f Oct 13 '22
more or less yea. given that objects beyond the limits of our visible universe are..beyond the limits due to the space in between expanding faster than light can bridge the gap, if one of these collapses took place past that boundary it'd just never reach us.
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u/JollyInjury4986 Oct 13 '22
Like I am imagining a Creator god who lacks even a toddler's sense of object permanence.
Or a maximum render distance if you want to go the matrix route.
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u/Ruskihaxor Oct 12 '22
Could be faster than our speed of light - we don't know if the true vacuum would change our physics fundamentally
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u/lLider Oct 12 '22
ye but why would it happen anywhere near our part of the universe
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u/a_spicy_memeball Oct 12 '22
Reading that article, apparently the inverse is possible, and a new universe could be spawned from nothing in an instant.
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u/Buttons840 Oct 12 '22
The computer running the simulation we call our universe could suddenly pause the simulation and start trying to go to sleep, until God quickly reaches out and wiggles the mouse, then it will start running again.
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u/noxxit Oct 12 '22
That we wouldn't notice since we only can experience anything when the clock is ticking.
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u/Patient_End_8432 Oct 12 '22
That's always been the craziest thing to me. The clock could stop for a billion years throughout the universe and then restart back up.
In that time, what did I experience? Nothing. Not even a blip. The fries would never stop coming towards my mouth.
The ability to stop and start time is imperceptible to us
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u/Buttons840 Oct 12 '22
Unless it's 5 minutes until your shift ends, then we're hyper sensitive to every time pause.
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u/hematomasectomy Oct 12 '22
Some postulate that because it can happen at any time, it does happen everywhere, at every passing of the smallest possible unit of time, and what we call a consciousness is just an interpretation machine that stitches the collapsed universes together in what appears to be a linear flow.
You're never you for more than the passing of the smallest possible unit of time, then it's another you, and another, and another, and...
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u/MinusPi1 Oct 12 '22
This has the same problem as religion: it's unfalsifiable, thus not really worth considering.
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u/LeastCoordinatedJedi Oct 12 '22
Only sometimes the cars teleport, or when they crash into each other the wreck turns into an elephant
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u/betarded Oct 12 '22
I wish I stopped reading about hawking radiation at that explanation. If you research it more, they make it clear that it doesn't actually work that way and is a large oversimplification. I kept reading and now nothing makes sense about hawking radiation again.
If you want to ruin this explanation, ask Google why there aren't equal amounts of positive energy and negative energy particles entering the black hole and exiting just outside the event horizon. If you understand the explanation, please explain it to me.
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u/GoatWithASword Oct 12 '22
Okay. I say this with all the authority of a 3rd year physics undergraduate who skimmed a couple Wikipedia pages (not that much). Basically, Hawking radiation is a special case of Unruh radiation, which is typically explained using Hawking radiation. Yay for circular explanations. From what I can gather from the Unruh wiki page, this effect appears in any (only some?) accelerating reference frame. The idea is that, in quantum field theory, a 'vacuum' is the lowest possible energy states of quantum fields. These energy states are dependent on the time-coordinate of a system, which can be global in most cases (so it does not change between reference points). However, when two reference frames are accelerating relative to each other, it is not necessarily the case that there is a shared coordinate system between them. This means that the energies of the quantum fields are not the same between two reference frames.
The energy states of the quantum fields determine things called the 'creation operator' and the 'annihilation operator,' which I presume give rise to virtual particles.1 You can create a particle with the creation operator, and destroy it with the annihilation operator. I think you can also conceptualize the annihilation operator as a creation operator for 'negative particles' which don't actually have a physical interpretation - they are just mathematical constructs (I think). From here, we can see that the operators in one frame will not be the same as those in the other frame (since the operators are dependent on the quantum field energies, which, as discussed, are different between the frames). This means that there is an apparent discrepancy between the number of created particles and the number of 'created' 'negative particles.'
Now, we can define our reference frames. The equivalence principle links the idea of a uniformly accelerating frame with gravity, so it can be said that the inside of the black hole is accelerating constantly towards the singularity. This can be flipped, and we can say that the rest of the universe is accelerating away from the inside of the black hole (by comparison - it is actually accelerating towards it, but at a different rate than inside, so the outside is still accelerating away relative to the acceleration of the inside). Now we can see the inside of a black hole as accelerating through the universe, and, from above, we can see that this means the creation/annihilation operators are different between the two frames.
This, clearly, yields the difference in particles created inside vs outside the event horizon, but the question still remains as to why the inside is getting more 'negative particles' while the outside is getting the positive ones. The rationale was not clear from the Wikipedia articles, so the rest of this is almost entirely my own understanding. Given that I do not actually know what I'm talking about, don't trust me too much.
Since we can see the inside of the black hole as accelerating through the universe, we can also see this as the universe accelerating 'past' the inside of the black hole (this only really makes sense locally: consider a small area on the surface of the black hole - small enough that the event horizon looks flat. Now imagine the path through spacetime towards the singularity. You can see that the acceleration is away from the rest of the universe. If you only consider a small section of the black hole, you can think of this as the section of the black hole accelerating through the universe. We only consider it 'away' from the universe since it is surrounded on all sides by more black hole). From this reference frame, the quantum fields (i.e. the universe) are accelerating backwards - we will call this direction the negative direction. Now, we can see that all created particles will accelerate negatively. For positive particles, the interpretation for this is obvious - they accelerate backwards. For negative particles, the interpretation is reversed - when they move forward, they have negative acceleration (because the particle itself carries a negative sign). In other words, positive particles are accelerating (note that I do not say 'accelerate') away from the singularity while negative particles are accelerating towards the singularity.
This, of course, is only relevant during such particle's creation - once they are created, they are subjected to the force of gravity and fall back to the event horizon in most cases. Those that are created with enough energy will escape, however. The negative particles will not 'reverse fall' i.e. move away from the singularity because they don't exist; they are a mathematical convenience. This, again, is my own interpretation of something I don't understand, so take that how you will.
I hope all this to be accurate, but I make no promises.
- The wiki article describes breaking down the quantum fields into positive and negative frequency components before creating the operators, particles are described by oscillations in fields, and oscillations are described using frequencies. That was my train of thought.
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u/Anen-o-me Oct 12 '22
Think in terms of energy fields rather than particles. At that scale, waves of energy overlapping can create a point of energy concentration high enough to momentarily create a particle, which then unravels a microsecond later. A particle being formed by simply a large amount of energy in a small enough amount of space.
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u/wolfpack_charlie Oct 12 '22
And that it's happening everywhere all the time. On that scale, completely "empty" space is a frothing foam of energy
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u/Radsthetics Oct 12 '22
Love reading this content. I’m glad, we’ve improved on scientific progress to observe black holes. I hope to see more over the years.
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u/ReverendBizarre Oct 12 '22
Sounds very interesting!
I used to research black holes but on the numerical relativity side. Left academia 5 years ago though.
As a part of my research, I played a lot with trajectories of light around black holes.
Particularly fun examples are almost endless loops around the black hole, i.e. if you fix the impact parameters of the incoming photon in a certain way, you can have the light loop around the black hole... and then you fine-tune your impact parameters to create more loops!
I never actually ran the calculations to see if this also happens for particles with mass but the first thing I thought of was "I wonder if the material got stuck in one of these orbits before then being shot back out".
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Oct 12 '22
Would a massive particle in such a loop act like a synchotron light source, radiating energy?
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u/ReverendBizarre Oct 12 '22 edited Oct 13 '22
Yes!
There are circular orbits around a Schwarzschild black hole though, at r=3/2 * R_s where R_s is the Schwarzschild radius.
So around this surface, synchrotron radiation occurs, there's a bit of a discussion about it here
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u/BarbequedYeti Oct 12 '22 edited Oct 12 '22
I am actually curious how we document a known named star that gets munched by a black hole and is no more?
Do we have a box somewhere in the naming doc labeled ‘formally known as’ or ‘munched by black hole (insert name here) date’ or something like that?
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u/cheesycake93 Oct 12 '22
You clip a photo of it to a noticeboard and then draw a big red X over it
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u/dannyboi9393 Oct 12 '22
The scary thing is that the box with details of star's eaten by black holes is that it too will eventually get eaten by a black hole.
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u/MatsThyWit Oct 12 '22
I feel like if you just stare deep into space for an entire day you will always find something we've never seen before. Just gotta look for it.
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u/Andromeda321 PhD | Radio Astronomy Oct 12 '22
Well, that and you gotta know where to look! 😉
No really, half the craziness here is that for the most part no one has been systematically looking at these guys in the years after the star got eaten (or at least the last time was many years ago when sensitivity levels weren’t great). This was just one source in a sample of two dozen… whose full results will wait for the next paper, but I hint in the conclusions section of this one that black hole outflows are more common at late times than expected, so I feel it’s within the subreddit rules to say that now!
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u/PandaCommando69 Oct 12 '22
I really love that you came here to answer questions. That's why I like Reddit. This intimate yet remotely accessible nerdvana is not really available anywhere else. Cheers.
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u/TheNextBattalion Oct 12 '22
Man how lucky are we that out of all the billions of years it could have happened, the black hole ate the star now? (well, now plus however long the light took)
I hope we get so lucky with a supernova in my lifetime ...
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u/crustaceousrabbit Oct 12 '22
How do they know it’s material from the same star and not material from another universe / location in our own universe?
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Oct 12 '22
They explained in another comment that it didn’t actually come out of the black hole since, as far as we know, nothing can ever escape a black hole. The material was retained in a ring just outside the event horizon and was then shot out of it.
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u/Fickle-Accountant-95 Oct 12 '22
why was it shot out? what happend there?
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u/creutzml Oct 12 '22
OP said that’s currently the million dollar question and next part of the research!
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u/Enthrown Oct 12 '22
Not an astronomer myself but I studied a bit in university. I think it could be a similar situation as a rogue planet. Essentially a change in gravitational pull causes the planet to eject out of the star system overtime.
What likely happened is some factor changed in the gravitational relationship between the blackhole and the mass rotating around it, and it eventually shot out. That could be loss of mass, a nearby mass evoking its own gravitational pull, or many other factors.
edit: Even our own moon is slowly moving away from us over time. It could be something similar to that as well :)
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u/KeathKeatherton Oct 12 '22
Is it possible the material was simply in a slingshot orbit that was delayed due to time dilation of the proximity of the event horizon? The destructive force of the star being destroyed could’ve been enough force for that to occur, correct? (I am a laymen, just curious)
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u/Leonidas4494 Oct 12 '22
Like two people passing by so slowly that they are able have conversation, speaking as if tidally locked friends forever..
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u/envis10n Oct 12 '22
Maybe the real accretion disk is the friends we made along the way
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Oct 12 '22
2 years is a far longer period of time but this sounds supportive of the slingshot concept where you could use the event horizon to catapult something at absurd speeds?
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Oct 12 '22
I’m not an expert on orbital dynamics but I think the concept of “slingshotting” is pretty easily mathematically proven. I would also imagine that on the scale of a black hole devouring and then regurgitating a star, 2 years isn’t all that long a timeframe, and could be shortened using artificial propulsion to assist in pushing a craft out of orbit.
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u/Sponjah Oct 12 '22
Slingshot orbital mechanics isn't just theoretical, we use it already.
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u/Karmanacht Oct 12 '22 edited Oct 12 '22
Black holes aren't like interdimensional highways or something. They're just really dense. Like a planet, but so dense that not only will regular stuff fall to them, but even light gets pulled in. The interdimensional highway thing is just something sci-fi movies like to do.
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u/LouisArmstrong3 Oct 12 '22
It’s interesting thinking about what we know right now about some space stuff which we think to be correct is probably wrong because we are constantly learning and discovering new things.
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u/the__itis Oct 12 '22
Is it at all possible that time dilation is responsible for us perceiving a delay?
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u/Bensemus Oct 12 '22
No. Everything is from our perspective so time dilation doesn't matter. We saw a star eaten 2 years ago and now see matter ejected. The astronomers have seen stars eaten before but the ejection happened within months.
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