Note this website appears to be based around the personal theories of a scientist rather than a presentation of the consensus of the field.
Perhaps similar to somebody more famous like Harari in that respect.
The author appears to be legitimate in his scientific background but the repeated implications of the revolutionary nature of his work are somewhat crankish; this is a personal blog so possibly he just needs a good editor (he says he is published elsewhere).
Just something to bear in mind as you read - not that there isn't anything to gain from it; but the boundary between well-grounded theory and speculative philosophic beliefs may not be clear - which to be fair arguably comes somewhat with the territory here.
I found the article fascinating because it 'resonates' with my own personal truth.
I don't have the math background or a big enough brain to hold so many ideas, and equations, and relationships between all three, to come up with any kind of scientific explanation for why I believe what I believe.
The author seems to have it though.
Classic thinkers like Aristotle could still arrive at something that is true unto itself, without bringing in physics.
Any useful discussion between two entities must begin from some common knowledge: and because you have personal experience, you have knowledge, and therefore some idea of what is true.
Dirac says we should look for beauty in math: he didn't ever provide an explanation for why, just that it seems proper and something Mathematicians know only through experience. Philosophy is at the heart of truth.
We should argue against the author's theories. I can't, but I also won't dismiss his ideas just because it feels bad.
Using Aristotle's deductive reasoning, I also believe we exist within a black hole.
By examining intelligence and time: we can arrive at a conclusion that intelligence arises from observation if order that unfolds into chaos. And anything intelligent, anything able to notice the unfolding must itself resist chaos through localized order: intelligence.
We are the universe observing itself.
Intelligence and imagination allows us to predict future events.
I believe we all would make the exact same choices if we lived the exact same experiences in the same bodies. This makes me feel strangely connected, and keeps me more open-minded.
I'm a huge fan of Aristotle. He's more or less the founding father of all western intellectual tradition. But he believed things like continuous force is necessary to keep an object in motion and object released from a rotational anchor would move perpendicular to the rotation's tangent. Beware any non-experimental version of science that relies entirely upon deducing what seems obvious to you from first principles. Even with strong math behind it, you get things like zero point energy density computed from quantum mechanics being off by triple-digit orders of magnitude from the true observed value, often called the worst prediction in the history of physics. Only reality, not your mind, holds truth. There is no "personal" truth, aside from true statements regarding your own feelings, beliefs, and other indicators of purely subjective internal state.
'A person is many things: some things are useful. And usefulness can apply to ourselves, or to others.'
I choose deductive reasoning from Aristotle and apply it to my own experience to reach my own conclusions. But you're right, he believed many things that turned out not to be true, and it reduces his credentials and should lessen how much belief I give to his ideas. Was the opening idea I left there 'useful' to you? I have no idea, it was useful to me.
But, if the tool is extremely useful, and feels elegant, perhaps there is some 'truth' to the tool itself and it should be considered carefully....
Someone literally posted an article about Dirac and 'beautiful math' here the other day. He suggested Einstein's special relativity persists today and spread because the idea was beautiful, and sake of beauty itself helped it to spread and be more 'true'.
Philosophy is how you come to determine that everything is made of different proportions of air earth water fire and aether. The physics are essential or it's just navel gazing. You may as well just have a 'personal truth' (what a gross term) about how many angels can dance on the head of a pin.
Not really. We use -logy to mean science or study of something. Philosophy with no other prefix is study of the Self, in a general sense, because Knowledge is a personal thing.
Science and Religion is a common division among intelligent beings. Sometimes they move forward differently in our minds singularly, and collectively.
You can accept truths like learning, knowledge, roles, collective intelligence, etc., and all the depth of the Science that goes with it, and still use those ideas at a high level in order to to predict future events, to do something 'useful'.
Google just posted a white paper about RSI 'dreaming'.
You take some super complex thing and reduce it within the scope of something bigger. Then you let an observer (self) recursively pick and choose the reduced scopes (like steps in a plan), and by observation of outcomes, pick the 'better path' for the future. It's like dreaming and reflection, considering past and future, and then choosing to learn in a direction that helps you change the future.
By picking and choosing in this way: you can learn and grow into shapes that help you predict the future again and again, to persist.
It's a loop within a loop, and that's neat to me (Cybernetics comes to mind). And so the author's idea tugs at me, because if we really do live in a Black Hole, what's at the end? A spikey but supremely ordered state, yet still a Singularity. What's at the beginning of the Big Bang? Also a Singularity, but extremely smooth. What's in the 'singularity' that is our moment right now: just our minds. The only thing that comes to mind is the 'you', the collective experience that defines your moment.
If you loosely connect the idea of a Big Bang being the beginning, and a Black hole being the end:
At one end: a single idea (low entropy, smooth ordered state: only on predictable event comes next, expansion), at another, many (high entropy, many predictable states if you consider the start, but always the same ending).
Intelligence is about predicting the state of one moment to the other, in order to do something useful about the future.
There's discussions and disruptions in Mathematics about: what makes a 'valid' Math proof? Do we accept only Human understanding, or Machines? Right now we've accepted Human only. The only way it matters, is if the discovery of proof is useful to someone or something.
Imagine an AI proofs out this author's work: If every single AI agreed, would you accept it? Or is AI actually a waste of 'Time' and we should stop using it. Is there beauty in Logic the way Dirac looks at Math?
As it is, we're waiting on some Humans to dig through Math and proof out and 'understand' in some areas, but not in others. We measure the utility of AI: how much time does it save, which means it's a very personal measure.
When it comes time to do this exercise where Science and Religion meet: we don't know if we should 'trust' an AI's understanding of Math over our own. We measure its utility differently in some areas than others...and so it becomes a very personal subject and is my 'stuff' to believe. My personal truth, as gross as it is. My 'shit to believe'.
To end this argument on a spiritual note that is also grounded in personal truth: consider loops once again.
And this time, probably the most important agent, the outer loop that matters most: Your beginning, and your ending. Your moment, is a collection of choices you make based on your own personal observation.
Whatever you believe: prepare for your own ending properly. Criticize when you feel it's proper, and help, when you see fit. Your choices.
Glossing over everything, but either you feel Descarte's 'I think, therefore I am', or you don't.
Singularities are interesting 'moments': places where timelines converge. One of these seems to exist at the 'Big Bang', and one seems to exist at the center of a 'Black Hole'.
This man's 'math' suggests we live in a black hole.
I'm not sure what you mean or why you have science in quotation marks.
I think he is trying to say that the fewer things we need to tune the better, but if so that's trivially Occam's razor and a standard part of the scientific toolkit.
His point is that in cosmology, that 'standard part of the scientific toolkit' isn't being used.
It also sounds as if he's discovered that PhDs are rewarded for work that makes their supervisor look good, not for original thinking that rocks the boat. You don't get the right to do that unless you have tenure at an Ivy (or foreign equivalent.)
The theory sounds interesting. I hope there are some testable predictions, and if there are, I hope they're tested.
Edward Arthur Milne's proposal was that the universe started out expanding. That is Milne cosmology, and oddly enough it's equivalent to Standard cosmology when you take out the gravitational effects of mass-energy. What's odd about that is that in Milne cosmology you have a big bang at one point with the edge moving at arbitrarily close to c and with uniform distribution of stuff and velocities, while in Standard cosmology we speak of the big bang happening everywhere all at once. This oddity is resolved when you realize that Milne is hyperbolic, so you if you "unfurl" a Milne universe it then looks the same as Standard excluding gravity.
I understand that, for a stationary black hole without spin (which does not exist), an object that falls into it will freeze, then the image will redshift until it disappears.
I also understand that there is a cosmological (event) horizon, where galaxies freeze, then rapidly redshift in the same way. This happens because these distant objects are accelerated away from us faster than light.
It appears to me that we are seeing black hole event horizons from the outside, and the cosmological event horizon is seen from the inside.
The similarities do give one pause.
The mechanisms are different; one is gravity, and the other is dark energy.
Not OP, but it’s not incompatible that dark-energy expansion (and ultimate big rip event) in a child universe correlates to the same process as black hole evaporation (and final event) for the originating black hole, if the “black hole universe” theory holds and they remain geometrically connected.
A black hole stands still? Would that not defy gravity? I mean a black hole also loses energy, right? So I would not expect it to be completely still. After all if you lose energy, you may also lose mass and shape and size - E = mc².
Still from a far away observer. As matter gets close to the event horizon, its local clock as viewed from far away slows down to the point of freezing completely when it reaches the horizon (this you won't see from outside).
As this happens, what you see is a very hard dimming of the emited light and a very hard redshift because everything takes so long now (from the perspective of a far away observer) that the frequency of the light emitted and the luminous power emited basically go to zero (along with everything that has time in the denominator).
What the Wikipedia article calls "evidence" is not actually evidence. It's not things we actually observe that are predicted by this model. It's just stuff that can be made to sound plausible in the model, if you assume for the sake of argument that the model is true.
And there is also one huge reason to not think such models are viable. The Wikipedia article skates right by it:
"According to such scenarios, our observable universe was born in a black hole existing in a larger universe, where this black hole may, at some point, appear as a white hole."
The problem with this is, a white hole has a past horizon. In other words, it is an isolated system with a horizon around it, and infinite empty space outside the horizon. We have no evidence for any such thing, and how would it be possible anyway? The past horizon would have had to be "built in" to the universe from the start. It's not something that can be produced by a physical process, the way a black hole, with its future horizon, can be formed by gravitational collapse.
I'd heard that hypothesis, but not that we seem to have evidence for it too.
Absolutely wild, thanks for sharing.
> Any model of the observable universe being the interior of a black hole requires that the Hubble radius of the universe be equal to its Schwarzschild radius, which is proportional to its mass. This is indeed observed to be nearly satisfied, but might be a coincidence.
> The only way to test the idea that black holes create new universes is to measure the observable universe. Inflation generated by spin and torsion is consistent with the cosmic microwave background data from the Planck satellite.
There is a video with John Baez and Philip Gibbs explaining why this is a common misconception. It's the same family of conceptual error, where things lining up just right allow incorrect conceptual reasoning to land at a correct answer shape, that allowed John Michell to work out the Schwarzschild radius of a star in the late 1700s.
With the blackhole universe picture, causal boundaries and spacetime's evolution aren't properly accounted for once we step out of a static picture.
Incidentally, the cosmic object we are more likely to be inside of is a white-hole.
My favorite idea is that the universe expands because mass-energy in our 4d parent universe is falling into our universe, which is a black hole. We exist as information upon the 4d hole’s 3d event horizon, and experience its inflation as our time dimension (as well as space inflation).
Inflation is accelerating because as the black hole grows it eats more.
Don’t know how crackpot this is. From what I’ve read it actually can be coaxed into fitting observation but there’s just no possible way to test it.
> “In physics, description is explanation” (author quoting his PhD advisor)
Yes, i have always hated this about physics. It is the only scientific field that apparently feels no responsibility to explain “why”, deciding that “what” is sufficient.
I wish the author all success so that i can someday read a satisfying answer to some of the “whys” of physics.
It's not that physics feels no responsibility to explain why, it's that all other fields of science answer the why by punting to some lower level of science that is taken as an assumption until you get down to physics which has nothing lower level to punt to.
Psychology explains why you feel tired by pointing to biology. Biology explains why cells need ATP by pointing to chemistry. Chemistry explains why ATP releases energy by pointing to physics. Physics explains that by pointing to some higher level form of physics like thermodynamics, which points to statistical mechanics, which point to quantum laws. When you get down to a certain level you simply have nothing left to punt to. You simply accept it because it's what's observed and makes reproducible predictions or you don't and go study philosophy or religion or something.
Yeah you’re right. And also part of it is that I simply don’t know enough deep physics to maybe start to get a more “intuitive” grasp on things.
But on the other hand I do feel there are cases where other fields have true explanations without punting. It’s not all the time but sometimes. My favorite example is evolution. We observe evidence that species evolve over long periods. Why? Natural selection. It’s the entire explanation. And I suppose in some senses it punts on the mechanisms of natural selection - genes and molecular biology rest on physics and chemistry after all. But in terms of the why, why does evolution happen, I feel we have a complete answer that has that feeling of intellectual satisfaction and completeness that is, at least from my lay perspective, lacking in physics.
There is philosophy, but common physicists does not like going there, unless for rare cases like the author or Max Tegmark or Roger Penrose...
So they goes round and round, using more and more "dials" to stay within their framework, always kicking the can down the road a bit (its turtles all the way down), but never really answering the core questions...
Description isn't explanation at all. That's bullshit.
Whys are teleological. No one knows why anything.
Hows are working models. And, as per Kuhn, they get updated regularly, but people get attached to them and they often need to die out before progress happens.
But really we're dealing with metaphors in mathematical form. There's likely some underlying ultimate substrate, but it's possible we may never understand it because it just won't fit inside our minds.
You can explain "the sun goes around to Earth" to almost anyone. "Orbits are ellipses" is high school level. Orbital perturbation theory is undergrad, and you've already lost maybe 90% of the population. The Einstein field equations are PhD level, and maybe a few thousand people out of a population of eight billion understand them.
If there's a level beyond that - and there probably is - we won't be able to access it bare-brained. The underlying metaphor may be explainable, possibly, but the math won't be.
And one of the defining features of science is that scientifc metaphors are counter-intuitive. Our brains evolved to understand spear throws, so we've built physics on physical experiences like mass, velocity, direction, and so on.
That gets really strained and broken in both relativity and quantum mechanics. In relativity spacetime is a bendy thing in its own right and 'time' doesn't work like normal clock time. And in QM all you really have are probability clouds that literally don't seem to have a physical foundation interacting with each other in very unintuitive ways.
I kind of like the idea that as the edge of the universe is observed, it expands to fit that observation. "Observed" being in the same sense as the uncertainty principle. But there's also the idea of the universe or space as a kind of mesh that's stretching, not really growing.
When I think about things at this scale, it really makes me feel minuscule.
I've always thought it would be interesting if the universe also operated on the principles of lazy evaluation, and the deeper you point the telescope, the more is rendered.
I like that too. It fits with the "there's no such thing as infinity, there's just really big numbers". So space is not infinite, it just doesn't have edges.
I feel cosmology ought to grapple more with, “Why is there something rather than nothing?” That question and this question are certainly linked. If expansion is a mirror of collapse, how do we get from some initial nothingness to a point where there is something capable of collapsing? Starting with an infinite amount of stuff everywhere feels like cheating.
But that’s cosmogony, not cosmology. Cosmology can just explore the cosmos that is there not having to worry about why it came to be. If there’s a causality of causality, then what’s the cause of itself.
I am absolutely certain that I read this same blog post on a 1990s geocities-style page, or nearly identical in content and prose.
I know this because I even showed it to my high school Astronomy teacher, who found it equally fascinating for entirely different reasons: I gave him a peek inside the wacky rabbit hole of the World Wide Web and he wanted more of it.
Anyway, can some please validate my memory? I do not want to experience this Mandela effect alone.
Fascinating article. I don't have enough knowledge to judge if the author's theory could make sense or not. But cosmology has always interested me, and I never liked the ad hoc and non-verifiable nature of some parts of the Big Bang theory. In particular of the inflation phase. So to me, any theory that gets rid of that is most welcome.
It's a nice fresh take. I like how naturally it comes that there's no singularity inside a black hole as there's no matter that can go through the event horizon in a finite time.
> In fact, this tendency for light and matter to slow cosmic expansion mathematically blows up to an infinite amount at the Big Bang
Well - the Big Bang theory could be wrong. Yes, one can assume it is logical, if everything expands then at one point it must have been closer together, a single point (though, has anyone determined this center yet?). But one could have different explanations. What if everything consists of strings of different energy streams? One could avoid having a Big Bang as theory there. Also, gravity has not yet been unified with other parts of the laws of physics, so realistically we don't fully understand gravity yet either. You have theories that right now do not explain everything.
I doubt very much the universe is expanding. The CMB doesn't present as a uniform field and is probably just noise from galaxies. There is too much vested religious interest in a finite and non-eternal universe for preconceptions not to cloud scientific observation. I call bullshit.
> The standard cosmological model affords no such explanation
Einstein GR → Friedmann eqns → universe can be expanding or contracting
Rest of this amounts to "what about initial conditions? things become divergent at t→0"
Yes, this is called the Big Bang singularity, GR breaks down there. You are not the first person to notice this. It is considered one of the biggest open problems in the field.
The stuff about accelerating expansion is confused (AI?) slop which eventually gets around to admitting that there's no problem at t>0 and no change to the existing problem at t=0, so I don't know why you didn't just cut it.
This is some real "unsolicited snail mail to physics departments"-tier content, even for HN I think it's embarrassing to have this on the front page.
I guess because every code monkey in Silicon Valley has wet dreams about overthrowing the hidebound physics establishment for some reason
Dunning Krueger is most prevalent in software engineers for some reason. Fortunately most of us grow out of it and begin to appreciate how hard other disciplines are.
One red flag that jumped out at me was, not a single link to a published paper, or even an arxiv preprint. Just other blog posts. Actual physics isn't done in blog posts. What has actually been published about all this for other physicists to critique? It's easy to make anything sound plausible if no one else but you gets to speak.
If you look on arxiv.org you will see all kinds of speculations by physicists that go outside our best current models. AFAIK a paper doesn't even have to be submitted for publication in a journal to be posted as a preprint there.
Also, there is always the alternative explanation that the reason other physicists have not paid any real attention to the author's claims is that those claims are, as I said in another post upthread, too vague even to criticize. (Wolfgang Pauli used the phrase "not even wrong".)
What stuff about accelerating expansion are you referring to? The author is a physicist not just a barstool talker. He's right as you point out that there are huge interesting and unexplained phenomena that sometimes have pretty little names that discourage further question asking. It's sad to see such negativity instead of engaging with the material a bit
While this is true, it's also true that out of all of his published work in physics (which you can find at the "Google Scholar" link on the Author page of his log), none of it, as far as I can see, is about the hypothesis described in this article. All his writings about that appear on his blog. Which means that, if he has tried to get any of this published in peer-reviewed journals, he's failed.
This could mean that he is a visionary whose insight is not recognized by the establishment, which is the story he tells. It could also mean that his speculations actually don't lead anywhere useful. My Bayesian prior is heavily on the latter.
I would say the appeal to authority was in the post I responded to: "the author is a physicist". I was simply pointing out that "physicist" is a broad term, and the fact that he has that job title doesn't automatically make him knowledgeable about the specific subject area in question.
As for the actual article, I think it's too vague to even be able to criticize anything specific. It's words strung together, but no actual testable model that I can see. (One key red flag: the page where he says the "mathematical details" are--does not even have a single equation.)
Physics/cosmology-related HN submissions tend to have poor comment quality, so this being upvoted to the front page isn’t too surprising, unfortunately.
Aren't laymen allowed to wonder about these things and share their thoughts?
You should remember that the groundwork on which all the scientific pursuits stands on was built by curious laymen ...Today it seems that without a Phd (apparently even that is not enough, given the reactions to this post), you are not allowed to ponder about such things...
Note this website appears to be based around the personal theories of a scientist rather than a presentation of the consensus of the field.
Perhaps similar to somebody more famous like Harari in that respect.
The author appears to be legitimate in his scientific background but the repeated implications of the revolutionary nature of his work are somewhat crankish; this is a personal blog so possibly he just needs a good editor (he says he is published elsewhere).
Just something to bear in mind as you read - not that there isn't anything to gain from it; but the boundary between well-grounded theory and speculative philosophic beliefs may not be clear - which to be fair arguably comes somewhat with the territory here.
I found the article fascinating because it 'resonates' with my own personal truth.
I don't have the math background or a big enough brain to hold so many ideas, and equations, and relationships between all three, to come up with any kind of scientific explanation for why I believe what I believe.
The author seems to have it though.
Classic thinkers like Aristotle could still arrive at something that is true unto itself, without bringing in physics.
Any useful discussion between two entities must begin from some common knowledge: and because you have personal experience, you have knowledge, and therefore some idea of what is true.
Dirac says we should look for beauty in math: he didn't ever provide an explanation for why, just that it seems proper and something Mathematicians know only through experience. Philosophy is at the heart of truth.
We should argue against the author's theories. I can't, but I also won't dismiss his ideas just because it feels bad.
Using Aristotle's deductive reasoning, I also believe we exist within a black hole.
By examining intelligence and time: we can arrive at a conclusion that intelligence arises from observation if order that unfolds into chaos. And anything intelligent, anything able to notice the unfolding must itself resist chaos through localized order: intelligence.
We are the universe observing itself.
Intelligence and imagination allows us to predict future events.
I believe we all would make the exact same choices if we lived the exact same experiences in the same bodies. This makes me feel strangely connected, and keeps me more open-minded.
I'm a huge fan of Aristotle. He's more or less the founding father of all western intellectual tradition. But he believed things like continuous force is necessary to keep an object in motion and object released from a rotational anchor would move perpendicular to the rotation's tangent. Beware any non-experimental version of science that relies entirely upon deducing what seems obvious to you from first principles. Even with strong math behind it, you get things like zero point energy density computed from quantum mechanics being off by triple-digit orders of magnitude from the true observed value, often called the worst prediction in the history of physics. Only reality, not your mind, holds truth. There is no "personal" truth, aside from true statements regarding your own feelings, beliefs, and other indicators of purely subjective internal state.
'A person is many things: some things are useful. And usefulness can apply to ourselves, or to others.'
I choose deductive reasoning from Aristotle and apply it to my own experience to reach my own conclusions. But you're right, he believed many things that turned out not to be true, and it reduces his credentials and should lessen how much belief I give to his ideas. Was the opening idea I left there 'useful' to you? I have no idea, it was useful to me.
But, if the tool is extremely useful, and feels elegant, perhaps there is some 'truth' to the tool itself and it should be considered carefully....
Someone literally posted an article about Dirac and 'beautiful math' here the other day. He suggested Einstein's special relativity persists today and spread because the idea was beautiful, and sake of beauty itself helped it to spread and be more 'true'.
Is this proper? I don't know.
Philosophy is how you come to determine that everything is made of different proportions of air earth water fire and aether. The physics are essential or it's just navel gazing. You may as well just have a 'personal truth' (what a gross term) about how many angels can dance on the head of a pin.
Not really. We use -logy to mean science or study of something. Philosophy with no other prefix is study of the Self, in a general sense, because Knowledge is a personal thing.
Science and Religion is a common division among intelligent beings. Sometimes they move forward differently in our minds singularly, and collectively.
You can accept truths like learning, knowledge, roles, collective intelligence, etc., and all the depth of the Science that goes with it, and still use those ideas at a high level in order to to predict future events, to do something 'useful'.
Google just posted a white paper about RSI 'dreaming'.
You take some super complex thing and reduce it within the scope of something bigger. Then you let an observer (self) recursively pick and choose the reduced scopes (like steps in a plan), and by observation of outcomes, pick the 'better path' for the future. It's like dreaming and reflection, considering past and future, and then choosing to learn in a direction that helps you change the future.
By picking and choosing in this way: you can learn and grow into shapes that help you predict the future again and again, to persist.
It's a loop within a loop, and that's neat to me (Cybernetics comes to mind). And so the author's idea tugs at me, because if we really do live in a Black Hole, what's at the end? A spikey but supremely ordered state, yet still a Singularity. What's at the beginning of the Big Bang? Also a Singularity, but extremely smooth. What's in the 'singularity' that is our moment right now: just our minds. The only thing that comes to mind is the 'you', the collective experience that defines your moment.
If you loosely connect the idea of a Big Bang being the beginning, and a Black hole being the end:
At one end: a single idea (low entropy, smooth ordered state: only on predictable event comes next, expansion), at another, many (high entropy, many predictable states if you consider the start, but always the same ending).
Intelligence is about predicting the state of one moment to the other, in order to do something useful about the future.
There's discussions and disruptions in Mathematics about: what makes a 'valid' Math proof? Do we accept only Human understanding, or Machines? Right now we've accepted Human only. The only way it matters, is if the discovery of proof is useful to someone or something.
Imagine an AI proofs out this author's work: If every single AI agreed, would you accept it? Or is AI actually a waste of 'Time' and we should stop using it. Is there beauty in Logic the way Dirac looks at Math?
As it is, we're waiting on some Humans to dig through Math and proof out and 'understand' in some areas, but not in others. We measure the utility of AI: how much time does it save, which means it's a very personal measure.
When it comes time to do this exercise where Science and Religion meet: we don't know if we should 'trust' an AI's understanding of Math over our own. We measure its utility differently in some areas than others...and so it becomes a very personal subject and is my 'stuff' to believe. My personal truth, as gross as it is. My 'shit to believe'.
To end this argument on a spiritual note that is also grounded in personal truth: consider loops once again.
And this time, probably the most important agent, the outer loop that matters most: Your beginning, and your ending. Your moment, is a collection of choices you make based on your own personal observation.
Whatever you believe: prepare for your own ending properly. Criticize when you feel it's proper, and help, when you see fit. Your choices.
> Using Aristotle's deductive reasoning, I also believe we exist within a black hole.
Wut
Glossing over everything, but either you feel Descarte's 'I think, therefore I am', or you don't.
Singularities are interesting 'moments': places where timelines converge. One of these seems to exist at the 'Big Bang', and one seems to exist at the center of a 'Black Hole'.
This man's 'math' suggests we live in a black hole.
>between well-grounded theory...
But how is the "dials" that the author describes, which "science" use to make the theory fit the facts of observation, more grounded?
I'm not sure what you mean or why you have science in quotation marks.
I think he is trying to say that the fewer things we need to tune the better, but if so that's trivially Occam's razor and a standard part of the scientific toolkit.
His point is that in cosmology, that 'standard part of the scientific toolkit' isn't being used.
It also sounds as if he's discovered that PhDs are rewarded for work that makes their supervisor look good, not for original thinking that rocks the boat. You don't get the right to do that unless you have tenure at an Ivy (or foreign equivalent.)
The theory sounds interesting. I hope there are some testable predictions, and if there are, I hope they're tested.
> His point is that in cosmology, that 'standard part of the scientific toolkit' isn't being used.
Yea, that is what I was trying to say in the comment above ...
[dead]
It is an unknown person for me that wrote something on the internet.
Why do you need to spell it out like that?
Edward Arthur Milne's proposal was that the universe started out expanding. That is Milne cosmology, and oddly enough it's equivalent to Standard cosmology when you take out the gravitational effects of mass-energy. What's odd about that is that in Milne cosmology you have a big bang at one point with the edge moving at arbitrarily close to c and with uniform distribution of stuff and velocities, while in Standard cosmology we speak of the big bang happening everywhere all at once. This oddity is resolved when you realize that Milne is hyperbolic, so you if you "unfurl" a Milne universe it then looks the same as Standard excluding gravity.
I understand that, for a stationary black hole without spin (which does not exist), an object that falls into it will freeze, then the image will redshift until it disappears.
https://en.wikipedia.org/wiki/Event_horizon
I also understand that there is a cosmological (event) horizon, where galaxies freeze, then rapidly redshift in the same way. This happens because these distant objects are accelerated away from us faster than light.
It appears to me that we are seeing black hole event horizons from the outside, and the cosmological event horizon is seen from the inside.
The similarities do give one pause.
The mechanisms are different; one is gravity, and the other is dark energy.
https://en.wikipedia.org/wiki/Cosmological_horizon
I mean they’re similar because it’s the same thing happening… light not being able to reach us.
Maybe dark energy is inside-out gravity
What does that mean?
Not OP, but it’s not incompatible that dark-energy expansion (and ultimate big rip event) in a child universe correlates to the same process as black hole evaporation (and final event) for the originating black hole, if the “black hole universe” theory holds and they remain geometrically connected.
I’ll have to take your word for it, my general relativity isn’t that up to date… thanks for giving me context though!
A black hole stands still? Would that not defy gravity? I mean a black hole also loses energy, right? So I would not expect it to be completely still. After all if you lose energy, you may also lose mass and shape and size - E = mc².
Still from a far away observer. As matter gets close to the event horizon, its local clock as viewed from far away slows down to the point of freezing completely when it reaches the horizon (this you won't see from outside).
As this happens, what you see is a very hard dimming of the emited light and a very hard redshift because everything takes so long now (from the perspective of a far away observer) that the frequency of the light emitted and the luminous power emited basically go to zero (along with everything that has time in the denominator).
There are three parameters that define a black hole: mass, spin, and charge.
There is nothing preventing spin from being zero, as far as I know.
Because our universe is actually the inside of a blackhole.
https://en.wikipedia.org/wiki/Black_hole_cosmology#Evidence
What the Wikipedia article calls "evidence" is not actually evidence. It's not things we actually observe that are predicted by this model. It's just stuff that can be made to sound plausible in the model, if you assume for the sake of argument that the model is true.
And there is also one huge reason to not think such models are viable. The Wikipedia article skates right by it:
"According to such scenarios, our observable universe was born in a black hole existing in a larger universe, where this black hole may, at some point, appear as a white hole."
The problem with this is, a white hole has a past horizon. In other words, it is an isolated system with a horizon around it, and infinite empty space outside the horizon. We have no evidence for any such thing, and how would it be possible anyway? The past horizon would have had to be "built in" to the universe from the start. It's not something that can be produced by a physical process, the way a black hole, with its future horizon, can be formed by gravitational collapse.
I'd heard that hypothesis, but not that we seem to have evidence for it too.
Absolutely wild, thanks for sharing.
> Any model of the observable universe being the interior of a black hole requires that the Hubble radius of the universe be equal to its Schwarzschild radius, which is proportional to its mass. This is indeed observed to be nearly satisfied, but might be a coincidence.
> The only way to test the idea that black holes create new universes is to measure the observable universe. Inflation generated by spin and torsion is consistent with the cosmic microwave background data from the Planck satellite.
Wow speaking of asymmetries https://academic.oup.com/mnras/article/538/1/76/8019798?logi...
There is a video with John Baez and Philip Gibbs explaining why this is a common misconception. It's the same family of conceptual error, where things lining up just right allow incorrect conceptual reasoning to land at a correct answer shape, that allowed John Michell to work out the Schwarzschild radius of a star in the late 1700s.
With the blackhole universe picture, causal boundaries and spacetime's evolution aren't properly accounted for once we step out of a static picture.
Incidentally, the cosmic object we are more likely to be inside of is a white-hole.
https://www.youtube.com/watch?v=ULjLGTd3-4s
But our universe also has black holes.
So what then, is it black holes all the way down?
Fractal reality
Not so. You can have high enough mass-energy density and yet not a black hole because the momenta are all outward -- dynamics details matter.
Why there are anothder blackhole? Is there blackhole inside our blackhole?
My favorite idea is that the universe expands because mass-energy in our 4d parent universe is falling into our universe, which is a black hole. We exist as information upon the 4d hole’s 3d event horizon, and experience its inflation as our time dimension (as well as space inflation).
Inflation is accelerating because as the black hole grows it eats more.
Don’t know how crackpot this is. From what I’ve read it actually can be coaxed into fitting observation but there’s just no possible way to test it.
Pretty crackpot. Love it.
Whew, really fantastic article!
> “In physics, description is explanation” (author quoting his PhD advisor)
Yes, i have always hated this about physics. It is the only scientific field that apparently feels no responsibility to explain “why”, deciding that “what” is sufficient.
I wish the author all success so that i can someday read a satisfying answer to some of the “whys” of physics.
It's not that physics feels no responsibility to explain why, it's that all other fields of science answer the why by punting to some lower level of science that is taken as an assumption until you get down to physics which has nothing lower level to punt to.
Psychology explains why you feel tired by pointing to biology. Biology explains why cells need ATP by pointing to chemistry. Chemistry explains why ATP releases energy by pointing to physics. Physics explains that by pointing to some higher level form of physics like thermodynamics, which points to statistical mechanics, which point to quantum laws. When you get down to a certain level you simply have nothing left to punt to. You simply accept it because it's what's observed and makes reproducible predictions or you don't and go study philosophy or religion or something.
Yeah you’re right. And also part of it is that I simply don’t know enough deep physics to maybe start to get a more “intuitive” grasp on things.
But on the other hand I do feel there are cases where other fields have true explanations without punting. It’s not all the time but sometimes. My favorite example is evolution. We observe evidence that species evolve over long periods. Why? Natural selection. It’s the entire explanation. And I suppose in some senses it punts on the mechanisms of natural selection - genes and molecular biology rest on physics and chemistry after all. But in terms of the why, why does evolution happen, I feel we have a complete answer that has that feeling of intellectual satisfaction and completeness that is, at least from my lay perspective, lacking in physics.
Or, as the old joke goes:
> Psychology is really biology; biology is really chemistry; chemistry is really physics; physics is really math; and math is really hard.
There is philosophy, but common physicists does not like going there, unless for rare cases like the author or Max Tegmark or Roger Penrose...
So they goes round and round, using more and more "dials" to stay within their framework, always kicking the can down the road a bit (its turtles all the way down), but never really answering the core questions...
You could say meta-biology is called chemistry and meta-physics is just called meta-physics.
Description isn't explanation at all. That's bullshit.
Whys are teleological. No one knows why anything.
Hows are working models. And, as per Kuhn, they get updated regularly, but people get attached to them and they often need to die out before progress happens.
But really we're dealing with metaphors in mathematical form. There's likely some underlying ultimate substrate, but it's possible we may never understand it because it just won't fit inside our minds.
You can explain "the sun goes around to Earth" to almost anyone. "Orbits are ellipses" is high school level. Orbital perturbation theory is undergrad, and you've already lost maybe 90% of the population. The Einstein field equations are PhD level, and maybe a few thousand people out of a population of eight billion understand them.
If there's a level beyond that - and there probably is - we won't be able to access it bare-brained. The underlying metaphor may be explainable, possibly, but the math won't be.
And one of the defining features of science is that scientifc metaphors are counter-intuitive. Our brains evolved to understand spear throws, so we've built physics on physical experiences like mass, velocity, direction, and so on.
That gets really strained and broken in both relativity and quantum mechanics. In relativity spacetime is a bendy thing in its own right and 'time' doesn't work like normal clock time. And in QM all you really have are probability clouds that literally don't seem to have a physical foundation interacting with each other in very unintuitive ways.
I kind of like the idea that as the edge of the universe is observed, it expands to fit that observation. "Observed" being in the same sense as the uncertainty principle. But there's also the idea of the universe or space as a kind of mesh that's stretching, not really growing.
When I think about things at this scale, it really makes me feel minuscule.
I've always thought it would be interesting if the universe also operated on the principles of lazy evaluation, and the deeper you point the telescope, the more is rendered.
That or that it's all a fractal!
I like that too. It fits with the "there's no such thing as infinity, there's just really big numbers". So space is not infinite, it just doesn't have edges.
Attempts to tackle why in science are actually, underneath, just a how-it-really-happens, or what-happens answers.
No scientist can explain the why, and most can't even explain the how (Heisenberg uncertainty, for one accessible example).
The fact that i am being downvoted on my previous comment means i am on to sth. Truth maybe?
I didn't really understand what you wrote in your comment above. Re-phrase a bit maybe?
Sure. In the first comment: science can only explain what happens, and even that, with no certainty.
In the second comment: my first comment was getting downvoted heavily by the pseudo-quacks whose religion is science.
I feel cosmology ought to grapple more with, “Why is there something rather than nothing?” That question and this question are certainly linked. If expansion is a mirror of collapse, how do we get from some initial nothingness to a point where there is something capable of collapsing? Starting with an infinite amount of stuff everywhere feels like cheating.
But that’s cosmogony, not cosmology. Cosmology can just explore the cosmos that is there not having to worry about why it came to be. If there’s a causality of causality, then what’s the cause of itself.
I am absolutely certain that I read this same blog post on a 1990s geocities-style page, or nearly identical in content and prose. I know this because I even showed it to my high school Astronomy teacher, who found it equally fascinating for entirely different reasons: I gave him a peek inside the wacky rabbit hole of the World Wide Web and he wanted more of it.
Anyway, can some please validate my memory? I do not want to experience this Mandela effect alone.
Fascinating article. I don't have enough knowledge to judge if the author's theory could make sense or not. But cosmology has always interested me, and I never liked the ad hoc and non-verifiable nature of some parts of the Big Bang theory. In particular of the inflation phase. So to me, any theory that gets rid of that is most welcome.
It's a nice fresh take. I like how naturally it comes that there's no singularity inside a black hole as there's no matter that can go through the event horizon in a finite time.
It’s not expanding. It’s rotating in the 4th dimension.
Tomayto, tomahto? Mathematically speaking, I mean.
> In fact, this tendency for light and matter to slow cosmic expansion mathematically blows up to an infinite amount at the Big Bang
Well - the Big Bang theory could be wrong. Yes, one can assume it is logical, if everything expands then at one point it must have been closer together, a single point (though, has anyone determined this center yet?). But one could have different explanations. What if everything consists of strings of different energy streams? One could avoid having a Big Bang as theory there. Also, gravity has not yet been unified with other parts of the laws of physics, so realistically we don't fully understand gravity yet either. You have theories that right now do not explain everything.
is pointless to say the universe expands. We don't even know where it ends or begins
I doubt very much the universe is expanding. The CMB doesn't present as a uniform field and is probably just noise from galaxies. There is too much vested religious interest in a finite and non-eternal universe for preconceptions not to cloud scientific observation. I call bullshit.
If it weren't expanding wouldn't the points of light from the 100s of billions of galaxies remain for us see in the visible spectrum?
>Physics conjecture
>Looks inside.
>Zero math.
Zero effort slop.
to have enough space to accommodate your mom … I’m so sorry for this joke
> The standard cosmological model affords no such explanation
Einstein GR → Friedmann eqns → universe can be expanding or contracting
Rest of this amounts to "what about initial conditions? things become divergent at t→0"
Yes, this is called the Big Bang singularity, GR breaks down there. You are not the first person to notice this. It is considered one of the biggest open problems in the field.
The stuff about accelerating expansion is confused (AI?) slop which eventually gets around to admitting that there's no problem at t>0 and no change to the existing problem at t=0, so I don't know why you didn't just cut it.
This is some real "unsolicited snail mail to physics departments"-tier content, even for HN I think it's embarrassing to have this on the front page.
I guess because every code monkey in Silicon Valley has wet dreams about overthrowing the hidebound physics establishment for some reason
Dunning Krueger is most prevalent in software engineers for some reason. Fortunately most of us grow out of it and begin to appreciate how hard other disciplines are.
>unsolicited snail mail to physics departments..
Would Ramanujan's unsolicited letter to Hardy be one of the kind that you describe here?
> this is called the Big Bang singularity, GR breaks down there.
Only in models that actually have such an initial singularity. Not all models do. Eternal inflation models, for example, do not.
One red flag that jumped out at me was, not a single link to a published paper, or even an arxiv preprint. Just other blog posts. Actual physics isn't done in blog posts. What has actually been published about all this for other physicists to critique? It's easy to make anything sound plausible if no one else but you gets to speak.
Probably because physicists are not going to entertain stuff that is trying to get them out of their comfort zone...
If you look on arxiv.org you will see all kinds of speculations by physicists that go outside our best current models. AFAIK a paper doesn't even have to be submitted for publication in a journal to be posted as a preprint there.
Also, there is always the alternative explanation that the reason other physicists have not paid any real attention to the author's claims is that those claims are, as I said in another post upthread, too vague even to criticize. (Wolfgang Pauli used the phrase "not even wrong".)
>Actual physics isn't done in blog posts
Wolfram didn't get the memo
What stuff about accelerating expansion are you referring to? The author is a physicist not just a barstool talker. He's right as you point out that there are huge interesting and unexplained phenomena that sometimes have pretty little names that discourage further question asking. It's sad to see such negativity instead of engaging with the material a bit
> The author is a physicist
While this is true, it's also true that out of all of his published work in physics (which you can find at the "Google Scholar" link on the Author page of his log), none of it, as far as I can see, is about the hypothesis described in this article. All his writings about that appear on his blog. Which means that, if he has tried to get any of this published in peer-reviewed journals, he's failed.
This could mean that he is a visionary whose insight is not recognized by the establishment, which is the story he tells. It could also mean that his speculations actually don't lead anywhere useful. My Bayesian prior is heavily on the latter.
Why do you have to use your statistics, when you can use arguments addressing the problems in the articles?
Sounds lot like you are using appeal to authority.
I would say the appeal to authority was in the post I responded to: "the author is a physicist". I was simply pointing out that "physicist" is a broad term, and the fact that he has that job title doesn't automatically make him knowledgeable about the specific subject area in question.
As for the actual article, I think it's too vague to even be able to criticize anything specific. It's words strung together, but no actual testable model that I can see. (One key red flag: the page where he says the "mathematical details" are--does not even have a single equation.)
> I guess because every code monkey in Silicon Valley has wet dreams about overthrowing the hidebound physics establishment for some reason
Too much focus on the tech in Star Trek when you're a kid, I imagine. Shoulda focused on the morality.
Physics/cosmology-related HN submissions tend to have poor comment quality, so this being upvoted to the front page isn’t too surprising, unfortunately.
Aren't laymen allowed to wonder about these things and share their thoughts?
You should remember that the groundwork on which all the scientific pursuits stands on was built by curious laymen ...Today it seems that without a Phd (apparently even that is not enough, given the reactions to this post), you are not allowed to ponder about such things...