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technohacker, w Eliminating singularities: Physicists describe the creation of black holes through pure gravity
@technohacker@programming.dev avatar

Gonna hijack this post to ask a somewhat related but possibly stupid question, would it be possible that instead of a singularity there happened to be a region of space with non-negligible size (ie, not a point sized region) that acted like a well instead? Things could “fall” into that well and not be able to escape, but it’s not like everything in the well is at a single point.

e0qdk,
@e0qdk@reddthat.com avatar

I may be misunderstanding your question, but black holes are regions of space that have non-negligible size; the boundary between what can escape and what can’t is called the event horizon. The singularity is what happens at the center.

technohacker,
@technohacker@programming.dev avatar

Ah right I worded that wrong, sorry!

I guess what I mean to say is, would a non-negligible sized “singularity” (I know I’m messing with that term quite a bit, I’ll stray from the mathematical definition) be consistent with our current theories?

BaroqueInMind,

No one can get information from beyond the event horizon, so no one can truly know besides predict with math.

Tarquinn2049, (edited )

Basically, what makes sense logically isn’t backed up by what data and math we have. Logically, we would assume as enough stuff is pulled together that the density hits a point where gravity is stronger than the bonds that hold matter together, that those bonds would break and the individual elements, initially atoms, but as gravity gets stronger and stronger the bonds between the components of atoms and so on and so forth also break down.

At some point, there is a limit to how much matter can break back down into further and further smaller components. What specifically happens when that limit is reached? That is a huge part of what could be throwing the math off. We don’t really know, but we have some guesses. Could be at the end, one of the components is weightless, and unaffected by the gravity, we do see some energy radiating out of some black holes in a straight line or “jet”. Hard to say for sure. Logic doesn’t always get us there when we don’t have enough data and need to make a leap. It might eventually, as we can slowly tie more and more stuff together with more data. Could be whatever energy starts that jet either immediately or already on the way out, mixes/mixed with other components and particles to become what we end up detecting it as. But if we could see it earlier, it maybe would be completely different before that.

gnutrino,

Depends what you mean by “our current theories”. In classical General Relatively the answer is pretty conclusively no but many people think that a quantum theory of gravity should be able to remove the singularities. In fact, this article is about an attempt to do just that with a fairly natural extension to GR (albeit one that is only mathematically tractable in 5 or more dimensions) and seems to have succeeded for the static spherically symmetric case at least.

lemming,

Nobody really thinks singularities exist. It’s only what comes out from our math. That’s also how we know our math is wrong, we’re just not sure yet how to do it better.

Sunsofold, w Two Grand Canyon-size valleys on the far side of the moon formed within 10 minutes, scientists say

Oh wow. I only have one crack in my backside.

pjwestin, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032
@pjwestin@lemmy.world avatar

That’s 0.9% more than the last time I checked. I know those are still really low odds, but we can hope…

xor,

don’t worry, it’ll just be like a small nuke, not a planet killer… (until they update the size estimates)

psud,

One of the things they’re doing is calculating what it’s orbit would have to be to hit the Earth, and where it would have had to have been on its last orbit to be in that orbit

So they can look at any astronomical images of that part of the sky from then and see if it’s in the right place

If they find images of the right part of the sky at the right time and the asteroid is not in it, they know it’s not on an orbit that will hit the Earth in 2032

quediuspayu,

I science podcast I follow already warned last week that the probability would go up at first as they narrow down its trajectory.
They gave the example of a fan closing, as it gets narrow, the earth represents a bigger percentage of the remaining fan. If you keep closing the fan the Earth eventually will fall outside the fan and the percentage drop to zero.

Unless it turns out that it is dead center.

duskfall, w Astronomers Say They Have Spotted the Universe’s First Stars

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duskfall, w A radio transient with unusually slow periodic emission

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duskfall, w How to Clean the Primary Mirror of a Dobsonian Telescope.

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BlippyTheWonderSlug, w Two Grand Canyon-size valleys on the far side of the moon formed within 10 minutes, scientists say
@BlippyTheWonderSlug@ieji.de avatar

@fossilesque
It was Marvin, with a Deutonium Q-38 Space Modulator, from ACME. (obstructing his view of Venus)

shoulderoforion, w Two Grand Canyon-size valleys on the far side of the moon formed within 10 minutes, scientists say
@shoulderoforion@fedia.io avatar

that's what they want you to believe, they still haven't shown us the monolith

adam_y, w Two Grand Canyon-size valleys on the far side of the moon formed within 10 minutes, scientists say
@adam_y@lemmy.world avatar

“About 3.8 billion years ago” in case the title has you freaked.

seathru,
@seathru@lemmy.sdf.org avatar

Yeah, that was definitely some clickbait.

I would hazard to say that most major features of the moon created in the last couple billion years have done so in under 10 minutes.

maegul, w Euclid discovers a stunning Einstein ring
@maegul@lemmy.ml avatar

I’m confused about what exactly the ring is in the image or the main image at least. There seems to be an enhanced image in the article that highlights the ring more clearly as an outer edge, which makes sense (I suppose).

But I don’t understand what I’m to make of the top image. It’s the diffuse light part of the ring?

Balthazar,

You need to zoom in to the center of the bright elliptical. It would have been easier to see without zooming if they’d subtracted off the elliptical.

maegul,
@maegul@lemmy.ml avatar

Ah yes! Thanks! The enhanced image does day “close up” after all! A bit lazy of me!

Very cool though! A zoomed inset in the main image would have helped I think.

Hobbes, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032

Is there any way to get it here sooner?

Thcdenton, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032
@Thcdenton@lemmy.world avatar
blackstampede,

Unexpected Waterworld dipstick guy

Thcdenton,
@Thcdenton@lemmy.world avatar

He’s my go-to for posts like these

blackstampede,

Underutilized meme format, honestly. It can apply to almost anything in daily life circa 2025.

llamacoffee, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032
@llamacoffee@lemmy.world avatar

Wow this is the most depressing comment section I’ve ever seen.

threelonmusketeers,

Yeah, even for Lemmy this is bad. I hope most of them are semi-facetious?

Swedneck,
@Swedneck@discuss.tchncs.de avatar

it’s just standard “haha self harm funi”, it’s so easy to post and reliably gets a few upvotes, so it’s just a kneejerk response to posts like these.

DragonTypeWyvern, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032

Fucking finally goddamn

MrTrono, w Don’t panic, but an asteroid has a 1.9% chance of hitting Earth in 2032

Am I supposed to panic because it’s unlikely to hit? Meanwhile I’m out here wishing for death by meteor.

threelonmusketeers,

Just in case this comment is not a joke, here’s the WHO page on suicide prevention.

Either way, there are a few billion other people on this planet who would rather not die by meteor, thank you very much.

PhobosAnomaly,

I mean, if I was going to go out, then getting my shit mixed by a meteor is pretty awesome. I’m sure I’ll make it on to a few Buzzfeed articles over the next ten or twenty years.

All things considered though, it would indeed be nice if it landed somewhere inconsequential like the ocean; the desert; or Florida.

threelonmusketeers, (edited )

Florida

You jest, but the Kennedy Space Center is in Florida. Putting the world’s busiest spaceport out of commission might put a damper on future asteroid deflection missions…

grue,

Eh, they can launch from Vandenburg if it’s that important. (Or, ya know, Guiana or Baikonur or whatever.)

Mirshe,

Assuming any foreign space agency will work with NASA now…

murmelade,

Hell yeah this would be my choice too on preferred way to die. There’s something beautifully deterministic about it, a random space rock flying around for millions of years and all my lifes choices and circumstances ending up in standing on the exact spot the meteorite ends its journey. Right in my head. Lovely.

ShaggySnacks,

What about hitting the Republican National Conference?

lordnikon,

Not to be a doomer but most of us will be dead by then I just hope the meteor takes out any lucky oligarchs still alive in a bunker.

Omgpwnies,

You think “most of us” will be dead in … 7 years? That’s pretty doomer if you ask me.

lordnikon,

I just read the ipcc reports and if you read those and don’t start a bucket list for the time we have left. I don’t know what to tell you. Trust me I don’t want to be this way I will fight where I can but I’m going to live my life the same time way a terminal patient lives. Cherish the days we got and if I’m wrong I will eat crow happily with a big smile on my face.

llamacoffee,
@llamacoffee@lemmy.world avatar

Very doomer. Does lemmy have a “remind me in 7 years” bot? 😅

LouNeko,

Yeah I’ll take one for the team. I go to the point of impact and when it finaly hits, I’m gonna try to punch it back into orbit.

You don’t have to thank me.

joelfromaus,
@joelfromaus@aussie.zone avatar

Honestly, at this point, there might be enough of us volunteering to bounce that fucker back to Jupiter. A lot of us will be turned into jam but I think it’s worth the sacrifice.

MrTrono,

But I’m on team meteor

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