This is partly why I roll my eyes when people who don't do research in a field start telling me about the "studies [they] found" while researching a topic. Unless you know the field and the research methods and have actually practiced them, reading studies is pointless, because you're too ignorant to evaluate them.
Dead Stars Don’t Radiate
71–80 of 155 posts
Re: Dead Stars Don’t Radiate
#72Earlier quoted context omitted.
How are they getting blasted in the face when such a blast would necessarily have to be moving faster than light?
Because time slows down relative the outside observed as you get closer to the event horizon any matter falling inwards starts to compress blocking the matter above it until eventually that matter is compressed to an extreme against the event horizon. The photons that get fired off from that interaction away from the black hole are able to escape and that's why we can see some black holes as being extremely bright. H…
Ah, I gotcha, thanks for explaining. Yeah the 'accretion disk' are what this is normally called. Lots of matter is getting smashed right outside the EH, creating heat energy, and like you said it's able to blast out photons.
Re: Dead Stars Don’t Radiate
#73> It would also mean that quantum field theory in curved spacetime can only be consistent if baryon number fails to be conserved! This would be utterly shocking. Is it really shocking (today)? I mean, isn't this a logical consequence of Hawking radiation for black holes? I thought we were shocked by this a long time ago, but now we're ok with it. The authors of the paper in question may very well be wrong in their ca…
Also, the Standard Model does allow nonconservation of baryon number, nonperturbatively.
Re: Dead Stars Don’t Radiate
#74> It would also mean that quantum field theory in curved spacetime can only be consistent if baryon number fails to be conserved! This would be utterly shocking. Is it really shocking (today)? I mean, isn't this a logical consequence of Hawking radiation for black holes? I thought we were shocked by this a long time ago, but now we're ok with it. The authors of the paper in question may very well be wrong in their ca…
I'm not sure what more you want from him, there are many papers and even a textbook linked? It's bloody John Baez, the man knows his stuff. On you actual point, it is shocking because its claimed that baryon number is not conserved without black holes getting involved
> shocking because its claimed that baryon number is not conserved without black holes getting involved
Isn't it also speculated that there's hawking radiation caused by the event horizon at the edge of the visible universe in an accelerating frame?
Re: Dead Stars Don’t Radiate
#75There's an issue this highlights and it's not that the original authors were stupid so much as there's clearly a lot of knowledge held in silos. That's not a good thing if your goal is to advance everyone's knowledge. Whatever is going on in academia is failing relatively closely related fields which is not good.
> clearly a lot of knowledge held in silos.
I don't think it's quite that, since the eventual goal is to publish, not only publicly, but as publicly as possible. More like it seems like everyone tends to hold their cards quite close to their chest until the moment of pre-print publication. Which means you can be working on something that someone could have told you months or years ago you have a problem.
The scientific equivalent of polishing a branch before making a pull request, only to be told "this has a huge memory leak and moreover what you want already works if you use this other API".
I'm not really sure there's a human-scale solution: the research landscape is so vast that you can't connect everyone to everyone else and have everyone in need of valuable input get it, and have everyone able to give it not be inundated with half-baked rubbish. Even if you assume everyone from the top to bottom has pure motivations and incentives for doing the research in the first place (in the pull request analogy CVE spammers, for example).
Perhaps not having the universities themselves so keen for PR that they'll slap a press release together about anything that looks clickable without due diligence would at least prevent making a public spectacle outside of the academic circle now and then, but it wouldn't solve the fundamental issues.
Re: Dead Stars Don’t Radiate
#76Good news for boltzmann brains
Re: Dead Stars Don’t Radiate
#77Anyone that predicts an event that far out in the future let alone 100 years out I would bet against any day of the week. This is couple trillion of trillions years using physics no way of proving
Re: Dead Stars Don’t Radiate
#78Good news for boltzmann brains
One can argue there are 8billion Boltzmann brains on earth already
Re: Dead Stars Don’t Radiate
#79Is there a simple way to understand why massive objects don't radiate gravitationally? Accelerating observers see a bath of thermal radiation via something called the Unruh effect. If you're standing on a planet, you're accelerating under gravity, and therefore don't you see Unruh radiation? Does this have any connection to Hawking radiation?
Re: Dead Stars Don’t Radiate
#80> As Mark Twain said, “A lie can travel around the world and back again while the truth is lacing up its boots.” Actually he probably didn’t say that—but everyone keeps saying he did, illustrating the point perfectly. Well played.
"As Mark Twain famously never said" (c)