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Dark energy from supermassive black holes? Physicists spar over radical idea

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Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#31
post #24

Earlier quoted context omitted.

> Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? Sure. You seem to take issue with this notion. However, this very strategy lead to the discovery of elementary particles (neutrino) and planets (Neptune) in the past. It's how science works. > Obviously…

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Was the rudeness necessary?

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#33

Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…

> correct me if I’m wrong …

I think you’re oversimplifying, like seeing a forest and overlooking that it’s Prototaxites, not Malus domestica.

Here’s Sabine Hossenfelder’s curious-undergraduate-level history of Dark Matter theories:

https://youtu.be/4_qJptwikRc

Proper nouns include Renzo’s Rule and Baryonic Tully Fisher Relation.

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#35

Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…

It is very much a "if this, then that" situation.

We know how gravity works locally (for various definitions of local). We can calculate and predict with a lot of accuracy how objects in our immediate vicinity will behave.

All of the evidence is pointing to confirmation of our understanding of the situation.

Then this bullshit star three dozen light years away says "fuck that noise" and does something completely wild. Either we're wrong about all of our math or we missed something.

The "we missed something" crowd is the "dark energy"/"dark matter" people. And by "dark", they just mean "undetectable by current instruments". They believe our math is right. I believe the other crowd is the "Grand Unified Theory" people. That the math itself changes at scale.

And why is "85% of matter is undetectable at distance" not transformative to our assumptions? Do you realize the implications of that? That if 85% of what we should be able to perceive is imperceptible, then the "great silence" may be here sooner than we expect. Maybe that 85% is stuff that is just beyond the speed at which we'd be able to perceive it.

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#36

Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…

> I find it kind of funny that humans are so confident that our models of reality are correct that we truly think it's more likely there's just hidden "stuff" than there's just something hugely wrong with our idea of what the universe really is, and how it works. That's not how it works. Many a physics PhD has spent their career trying to come up with better models, including different sorts models of gravity or inde…

Dark matter is overfitted. This isn’t some comparative advantage it has. The number of parameters you set manually in many of these models is insane.

We are fundamentally missing something. Thankfully it’s just not all that important for us right now.

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#38
post #13

I'm a layman, but I like this idea intuitively. It's not mentioned in the article, but this theory also necessitates that black holes aren't singularities, which gets rid of what always seemed to me like the biggest hack in physics.

I've always wondered if the "horizon" metaphor in event horizon was more apt than we expected - just like when you approach the earth's horizon, you don't get flattened or fall off, you just reveal more geography - I've always wondered if it were possible that as you approach an event horizon you don't get "squashed into spaghetti" but just reveal more space which is just as "normal" as the space before you approached the horizon. But caveat - i have no real reason to actually believe this is true - I'll assume for now it's just poetic.

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#39

Earlier quoted context omitted.

> I find it kind of funny that humans are so confident that our models of reality are correct that we truly think it's more likely there's just hidden "stuff" than there's just something hugely wrong with our idea of what the universe really is, and how it works. That's not how it works. Many a physics PhD has spent their career trying to come up with better models, including different sorts models of gravity or inde…

Dark matter is overfitted. This isn’t some comparative advantage it has. The number of parameters you set manually in many of these models is insane. We are fundamentally missing something. Thankfully it’s just not all that important for us right now.

I mean, we already know about existing "dark" matter particles. The Neutrino comes to mind, though it's not massive enough to explain the gravitational phenomena. LCDM really isn't that weird or unexpected, since it's a lot like what we already observe, and we already think more particles should exist.

Re: Dark energy from supermassive black holes? Physicists spar over radical idea

#40

Earlier quoted context omitted.

> I find it kind of funny that humans are so confident that our models of reality are correct that we truly think it's more likely there's just hidden "stuff" than there's just something hugely wrong with our idea of what the universe really is, and how it works. That's not how it works. Many a physics PhD has spent their career trying to come up with better models, including different sorts models of gravity or inde…

Dark matter is overfitted. This isn’t some comparative advantage it has. The number of parameters you set manually in many of these models is insane. We are fundamentally missing something. Thankfully it’s just not all that important for us right now.

Can you give examples of these parameters that must be set manually?
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