February Video: Black Holes & Information Paradox
Added 2025-02-01 00:45:11 +0000 UTCSome house keeping at the start of this video.
Twitch: acollierastro
Messenger lectures: https://www.cornell.edu/video/playlist/leonard-susskind-messenger-lectures
John Michell: https://www.jstor.org/stable/106576?seq=2
Oppenheimer and Snyder: https://journals.aps.org/pr/pdf/10.1103/PhysRev.56.455
00:00 house keeping
07:36 black holes
22:00 information paradox
Comments
I've said more than enough on this topic already. I just want to give a shout out for your citing the letter of Rev. Michell from 1783. I finally finished it. His mention of the point where a light corpuscle's gravity would fully counteract its ability to escape is such a small detail in the argument. What I love about the letter is its interplay between theory & evidence. People who do observations have to synthesize diverse facts & theories, shape them toward their ends, to find out what they can at the present limits of our abilities. Here, he shows how we can calculate far beyond our direct observations for his day's foreseeable future, with excellent chances of landing fairly close to the truth. He is concerned with the problem of how to know the actual brightness of & distance to a star given only sundry facts we can ascertain, like apparent brightness & parallax. In the general case, we can't always decide. But take heart, he says, it's likely that we'll be able to bust thru in a small number of cases. Thus, he argues, we need to gather as much evidence together as we can so that someday, knowing more about that handful, we can continue the progress incrementally on the rest. Rev. Michell going the extra mile to eke out an inch, is inspiring. Another thing I love in reading old papers from so far back in time is that the physics is Newtonian. This paper is a long slog, but it's accessible to anyone with a few physics classes. Today we use some different jargon, like Doppler effect, redshift, & black hole, but the basic ideas don't need general relativity or the Schwarzchild solution, to be comprehended.
mykey6375
2025-06-18 23:14:48 +0000 UTCThe “my war with Stephen hawking” framing immediately sets off my alarm bells for me thanks to miniminuteman’s breakdown of ancient apocalypse. Graham Hancock just cannot shut up about how much mainstream archaeology hates him. Whenever someone talks like that, I don’t assume they’re talking crazy, but I do put my critical thinking ears on.
Mikayla Holland
2025-03-29 15:15:07 +0000 UTCimmediately reminded of how out of wack my concept of time is when you announced Nebula (oh hell yes) but also mentioned the tik tok ban stuff. UGH it feels like that happened years ago 😭
Marshall Elgin
2025-03-28 19:11:31 +0000 UTCYour fellow Nebula creator and Trekkie, Jessie Gender, has switched from opening with "Hello interwebs, I hope you're doing well," to "I hope you're doing as well as you can be," and I think we're all feeling that right now.
The Family Barlev
2025-02-12 02:35:09 +0000 UTCI like it because it doesn't cause my browser to crash (Firefox on Linux issues—GMeet causes my work laptop to overheat worse than if I'm running a numerical simulation).
The Family Barlev
2025-02-12 02:23:37 +0000 UTCDr. Collier, I have one other trifle that I'll try to substantiate. As I recall it, Hawking made an argument using a semiclassical quantum field model that a black hole would be seen at infinite time as having a temperature. He invented Hawking radiation to explain that. Pair production was the mechanism he came up with that might be how that could happen. He was reasoning top-down, not bottom-up, as you prefer to frame it (or so I gathered). I'd like to stand corrected. So I will be looking at the paper. But if you beat me to it, great. Even if your finding is that I was wrong. Thanks for your videos, they're all fantastic.
mykey6375
2025-02-10 01:15:59 +0000 UTCI accept your apology. Just kidding. I accept your suggestion to lower our oars & stop paddling.
mykey6375
2025-02-10 00:10:20 +0000 UTCAre you speaking to Michael or me? Just kidding. Sure, I was planning to watch a football game. As you know, I'm young & strong. I do lots of stuff like that. Especially the thing about breathing. As I said, there are things that made confusing things click for me, but they're too obvious, apparently. Smart people aren't able to identify them as the missing puzzle pieces they should use as examples in their lectures & textbooks. Clearly they aren't blocking for the bright students. But there are lots of people who could be adding their observations to the conversation, but their potential is limited by a small number of points of confusion. I'm not going to personally solve any truly difficult physics problems. But I can pass on the few stepping stones that got me across the creek to travelers behind me stuck on the far side.
mykey6375
2025-02-09 23:48:07 +0000 UTCI'll watch that in full. Meantime, the naked fact that Misali has five buckets suggests he's looking at a word that's used multiple ways as if this gets a handle on what the word can be used to convey, but I suggest it's a hint that there may be a tail in this distribution. As to the applicable sense being meaning 5, provisionally I'll say I don't see it. Maybe after I listen more, I'll come around. But offhand, I have to wonder who's the one gal & what is it she's confused about? And what's the framing absent that confusion? Well I'll say I think what's at stake is unitarity implies reversible, in principle. Quantum state disappearing at an inside edge (a black hole singularity) of the universe (manifold) would mean both that a thing that seems to happen within general relativity violates quantum mechanics, & a belief that both quantum mechanics & general relativity should be applicable in this situation is shattered. And, pending a change after I watch, my simple definition (based on two examples, Zeno's & Russell's paradoxes) is that when two seemingly valid chains of reasoning, both of which a reasonable person agrees with, give us apparently incompatible different answers, and we are stumped by it, we feel smacked in the nose by the wall, that's a sufficient condition for a problem to be called a "paradox". Both Zeno's & Russell's are solved, but many smart people were stumped before we figured them out. In the case of the black hole information loss "problem", we have the two valid arguments, different answers, we believe both, reasonably smart people were stumped. At least if you happen to be one of those people, paradox is a perfectly good word for that. If, like Dr. Collier, you can live with that situation, there's bigger fish to fry, then OK, you see that framing as hype. But still, what she's able to express without a better understanding of what's problematic than she was able to describe in this video, she won't be able to state the problem accurately enough for you to have an informed opinion. She has vague ideas that string theory & holography are important here because that's what she knows about Dr. Susskind's work, but that view, I don't think stands up to scrutiny. Which she's unmotivated to do. All I desire is to nudge her to seek a better handle on the subject. And I make excuses for Dr. Susskind because he was my professor. Dr. Collier lumps him in with Feynman Bros because that's a useful category for her. She's a grownup. Her life is her life. She's smart, funny, & utterly capable of making choices that are the best for her. It's up to her to watch the rest of a lecture or return to her book reading. Still, she predicted where in her video Feynman Bros would tune out, accurately. I would say that not watching takes a tiny bit of force out of the punch one can deliver on a subject. I disregarded comments from Feynman Bros once it became clear to me they took the shortcut. Am I principled, or shall I pick favorites & make excuses? I'm human. I don't know. It's a paradox.
mykey6375
2025-02-09 23:33:11 +0000 UTCThe main thing is nothing you said has anything to do with what I was talking about. I blame buzziness. There's no reason for any of this to be unpleasant. Rethink your approach to others.
Max Sonthonax
2025-02-09 22:40:36 +0000 UTCJust simmer down. Take a breath. It'll help.
Max Sonthonax
2025-02-09 22:35:26 +0000 UTCI said "if". "Hope for the best" would, hypothetically, express sympathy & condolence, but would, hypothetically, carry little of practical use in the sense of directed change of tactics. Does restating in tippy toe fashion cause you any less offence? If your way to seize the moment is nothing more than "reassess", I stand by what I suggested. If you have specific actions in mind that we can take in order to fulfill the promise, you could've maybe taken an extra breath to give us an example. Did you do that? Did I miss it? Or are you scoring points with vague truisms like the horoscopes & fortune cookies do? If it's not that, some substance will change my opinion immediately. Am I pretentious? Maybe, but I see some humility there. Am I a pompous ass? I suppose that terminology is applied depending on whose ox is gored. My take is that I'm not that. Yours is that I am. Maybe we should take it to pompous ass court.
mykey6375
2025-02-09 22:31:39 +0000 UTCAgain, I'm verbose. I've been accused of word salad. It's a price of learning things & having a vocabulary. I try to maintain at least a pose of grace & modesty. Maybe my ego is too much. But, you know, lots of people I look up to also have that problem. In spades. I don't look the other way, but for me, that's one consideration, not the whole ball game. As for you, you're, you know what, controlling, confrontational. How else would you reach a conclusion that a threat must be implied when I merely pointed out that your personal attack wasn't having your intended effect on me. That's a veiled threat, is it? As Dr. Collier has said in her videos multiple times, I wouldn't express an intention to send you email as a veiled threat, I'd just send you an email. Does word salad send shivers up your spine or something? What's up with that? Oh, you're putting me down. OK, fine. Please consider me put down.
mykey6375
2025-02-09 22:00:30 +0000 UTCRe: the topic of this being called a "paradox" but not being an actual paradox https://www.youtube.com/watch?v=ppX7Qjbe6BM jan Misali has an interesting video categorizing paradoxes, and this feels like it fits into the "one guy getting very confused, writing it down, and getting it published" category.
Brett C. S.
2025-02-09 21:54:55 +0000 UTCAre you threatening me? Are you going to send me an email with a word salad?
Jamie
2025-02-09 20:43:52 +0000 UTC@mykey6375 I couldn't find the comment here, but in my email notifications it sounds like someone told you to "shut up". For what it's worth please don't. I didn't follow everything you said but I learned some things (at least I think... in quantum theory it often turns out learning something for me just means I realize there is even more that I don't understand) from your replies. As someone who often sends book long emails and leaves book length comments myself, I appreciate detail and if something is too long or if I'm tired of one person's comments it isn't very difficult to just... you know not read them.
Michael DeBellis
2025-02-09 17:36:08 +0000 UTCI may be ridiculous, but I'm not stupid. I can see that, it's obvious as hell. But believe it or not, sometimes my ridiculous comments turn out to be helpful. Do you feel like ridiculing me? You can go ahead, what am I gonna do to stop you? So then I'm ridiculed & I deserve it & then what? Am I a bad person? I have a fair to middling brain, ideas that I feel are defensible, & am perfectly willing to retract or concede. And if no one else is writing or saying things that indicate they are aware of relevant details that I happen to have learned, & that they may be confused, I'm happy to explain. I'm jumping in here because I was once someone who knew nothing about black hole physics, but was given the opportunity to internalize a good chunk of it, have a mind that doesn't let facts sit there not making any sense, & can figure out what you have to understand about them to make them make sense. Like, that hovering above the event horizon is an accelerated reference frame. A rocket ship at a fixed altitude has to fire the rockets continually in order to stay in one place. The connection between accelerated reference frame and general relativity is immediate. It's easy peasy, but a lot of people are confused & when I tell them that, their eyes are the size of a bowling ball. Being ridiculous is a small price to pay.
mykey6375
2025-02-09 12:35:38 +0000 UTCDoesn't help.
Max Sonthonax
2025-02-09 10:38:33 +0000 UTCDo you ever feel ridiculous, even faintly?
Max Sonthonax
2025-02-09 10:37:51 +0000 UTCI want to get in one last jab. I don't think anyone says holography solves the information loss problem. The related idea called black hole complementarity which says that the apparent contradictory stories told by a hovering observer & an infalling one are compatible with QM because no single experiment can expose the contradiction, well, that proposal's author, as it happens, Dr. Susskind, now admits it's inadequate, & has effectively been withdrawn. The only way string theory fits into the discussion of this problem is that it provides an example that means we can probably construct a quantum field theory compatible with general relativity, since there's a string theory model that probably fits into that same gap. No one is claiming that string theory is the actual bridge. Dr. Susskind has always said he is not a string theorist. He flatly said a long time ago that the real world isn't supersymmetric. Holography itself doesn't derive from string theory, but rather from studying entanglement across regions of a quantum field theory. String theory is, yes, being used by researchers studying horizons, causal screens, & the like, as a math tool. cf. Ryu Takayanagi formula. Specifically, string theory's "explanation" why the black hole entropy area law is compatible with both GR & QM, also makes it credible that the entropy is in fact the quantum quantum quantum entropy. IOW, it's not a wavy-handed set of ensemble macrostates. Which could make almost any formula possibly some magical kind of "entropy". If it turned out the area law isn't fundamental, it'll end up in history's trash heap. And, apparently, there's a part of our spacetime's manifold where worldlines originating far away intersect the singularity. As far as we know, an object on such a worldline vanishes. In such a slice of our universe, some information that used to exist ends up missing. All of this extra decoration like event horizons & Hawking evaporation doesn't really do a thing to get rid of the underlying state loss problem. That's the reason a full-fledged quantum gravity theory might be helpful. Short of that, we have no way to get a handle on what new physics to drop into the placeholder now filled by that singularity that who knows what that physically means. Once equipped with a theory like that, we might be able to get a handle on many other slippery conundrums. You know, just like we're able to do thanks to those other early 20th century science miracles, GR & QM. I agree with you, we shouldn't get our hopes up. That is, we not only need a new theory, but we have to hope the new theory points us to ways to test it. Because as of now, we have no idea what phenomena we should be looking for.
mykey6375
2025-02-09 10:08:26 +0000 UTCSuch promise of opportunity is indistinguishable from risk. If the expected value of the best advice what to do is simply to hope for the best, that's self-evident & not worth the breath to express.
mykey6375
2025-02-09 09:02:36 +0000 UTCThank you, Jamie. I already volunteered to shut up. Yet, here we are. Your replies have already twice provoked me to respond. You might consider trying to resist poking the animals?
mykey6375
2025-02-09 08:56:04 +0000 UTCWell, that's not exactly it, either. They might be quite close to one another. The only difference between them is that by hypothesis one of them gets caught & the other gets away. If that's not so, then the most likely outcome wouid be mutual annihilation as usual. A long wavelength photon is "big" in the following sense. A short wavelength photon on a collision course with a black hole (or just a star) is likely to be captured (absorbed). The wavelength where a photon becomes likely to pass through (or maybe it's more like bend around the obstacle), is roughly the same as the star's width. Intuitively, we could say that wavelength is a kind of proxy for the "size" of a photon. Or that a long wavelength photon is stretched out. Its "position" is some random point where a detector happens to detect it. But it's "really" uncertain "where it was probable" to find it, with uncertainty of that magnitude. Taking this into account, we see that "the escaping photon appears to be spat out of empty space" is imprecise. A little more precisely, a typical Hawking radiation photon has such a long wavelength that the expected value of its point of origin is, rather than exactly at the event horizon, something like 100 black hole radii away, somewhere out in empty space.
mykey6375
2025-02-09 08:44:03 +0000 UTCThank you, Jamie. Or maybe I could say I was just photo bombing. Seriously, being compared to Bart Simpson is a kind of compliment. LoL Tell you what. I won't object if Dr. Collier decides to just delete all my comments. If she has to ask me to do it, I'll comply with neither hem nor haw. As for you, feel free to banter me to death.
mykey6375
2025-02-09 08:03:22 +0000 UTCUse your imagination
Novus
2025-02-09 07:35:10 +0000 UTCI love how bored you are
Jamie
2025-02-09 07:32:12 +0000 UTCWhat the ever loving shit are you saying?
Jamie
2025-02-09 07:29:39 +0000 UTCI think you are a little bit sick. Lay down, paracetamol
Jamie
2025-02-09 07:26:51 +0000 UTCDo the Bartman
Jamie
2025-02-09 07:12:55 +0000 UTCThank you for the explanation of the information paradox and holographic principle, this made more sense to me than whatever else I've heard before.
Adrian
2025-02-09 05:36:14 +0000 UTCOh I didn't know the wavelenght determined how close photon pairs appeared from each other. Although I'm sure it's not exactly how it works, I guess it's enough for now. Thanks!
dreamfyre
2025-02-09 04:19:41 +0000 UTCjust want to comment re: armageddon video -- the matrix has a strong trans reading to it, considering the wachowksi sisters. that's what makes it brilliant , since it fits with the general theme you had identified with eg fight club. glad to have a new video :)
Jack
2025-02-08 04:03:30 +0000 UTChttps://go.nebula.tv/angelacollier
mikeymad
2025-02-08 01:00:11 +0000 UTCDear Dr. Collier & your subscribers, It's not my place to be answering physics questions in your Patreon. But people are asking questions, you deserve your you-time, & even my amateur answers are better than nothing. A word to the wise, I mean, I can take a hint. If I'm out of line... Not that I have any plan to make a habit of this. Your following is here for you. I have a clear sense that they're addressing you directly. They don't think of their comments as on a public square. Or, not as much as in other venues. I am not a physicist. I concede all authority to Dr. Collier who is both smarter than me & more qualified in physics. I learned about BH physics from Dr. Susskind's classes available to the general public, which I took for 8 years. They were just lectures, no problem sets, nor exams. To the extent that Dr. Susskind may have been working at the cutting edge of something, we were exposed to that work. My prior physics learning was 2 years as a physics major at Stanford, textbooks were Paul Allen Tipler's Modern Physics, Shankar Principles of QM, The Berkeley Physics Course, & Feynman Lectures. I excelled at problem sets, aced my exams, & learned more from grading homeworks the following year than I had from doing the problems the first time. Of course my answer sheets had better answers than my original homeworks both bc I knew more physics & bc I wrote them up after grading papers. Point being, I know how much I learned decades later from Lenny. IMO he gave us more tools than my two rigorous years. He taught the math he needed us to have over the prerequisite of basic calculus including tensors, Christoffel symbols, Liouville thm, Legendre transforms etc. I do mean to upgrade to a voting subscription as I simultaneously cut others that are further above my pain point. I don't want to vote, I wouldn't have wanted you to do this topic, but I'll always be eager to hear what you think of anything. I trust you to choose what to create by any means you deem to help you. I don't equate my interests to any idea that passed thru my ears as to your goals. I tend to assume that my own choices are atypical in both this & most other circles. I'm happy for you, Dr. Collier, that you can be excited for something. I wish you a good life. Everything you said in this video was careful & essentially accurate. That said, I can add, I dunno, some context. That second Susskind book is meant as a primer for physicists outside the specialties of black hole entropy & quantum information. I can't solve the POD problem. Sorry, it sucks. Maybe we could start a list of POD books & book providers. But I suggest the physics presented in the info book is directly relevant to the question at hand. And I am in fact seeing *you* as its intended audience. Lenny arguably fleshed out Gerard's holography idea enough to be given some credit for the research direction that emerged from it. That may be seen as either a good thing or a bad idea. Juan's AdS/CFT work can be taken as a vindication of holography. OTOH, we could be skeptical. The conflict between GR & QM that arises bc of BH physics is that the seeming loss of "information" via the Hawking radiation is forbidden by unitary evolution. Equivalently, a) the Hawking radiation & the BH are a mixed state; b) the BH system changes state irreversibly. Now, we might call this a "paradox" bc as far as we know empirically, both GR & QM (QFT) sb valid in this situation. The overall relevance of BH physics, as Maldacena says, is the math of event horizons applies to both black holes & big bang theory. Deeper understandings of how our universe came into being & the relationship between gravity & quantum quantum quantum appear to be an opportunity for progress in multiple blocked directions where particle physicists want to push beyond their Standard Model theoretically but experiments seem to be at a dead end. Experimental evidence for the cosmological connection to QFT includes that an explicit quantum model of fluctuations predicts the surface of last scattering should make a rippled pattern as observed in the CMB. The connection to string theory is that Bekenstein's BH entropy bound has been explicitly modeled using string theory. That is, the entropy would be actual quantum microstates. Thus the conflicting predictions of GR & QM can be seen as not in contradiction. There's no other such model showing a similar result, by conventional or speculative means. I don't disagree with Dr. Collier's dismissive attitude towards this research direction. I agree, as I think so does Lenny, that thermo is on the whole more important to the body of physics. Like Dr. Collier, I'm a fan of PV=nRT. Right along with the Virial theorem. I don't know if Dr. Collier has heard of Nicole Yunger Halpern, whose posts I used to read on Preskill's blog, about her research direction which was at the time non-equilibrium thermo. I have not read Yunger Halpern's new book Quantum Steampunk. I'd be happy to get an opinion about it from Dr. Collier. That'd be swell. Because it's a new book, I can't get it used, ie, it's above my price cap. I don't usually do New Year's resolutions, but... I procured & set a deadline of 2025 on a lot of Dr. Collier's 2024 suggested books. Avg cost, a smidge over $5 each, used. I'd read LeGuin's 3 biggies in her Hainish "cycle" long ago, but now I'm gonna reread them along with all the rest, which are all available for 50 bucks as a 2-book box set. Thanks, Dr. Collier! P.S. The "Firewall Paradox" seemed to be a dagger to the chest of BH unitarity. The closest we've gotten to a solve of that is the proposal that the wavefunction of the BH "lives" in its interior until the "Page time" after which it discontinuously "lives" in the Hawking radiation. It calls into question the physical meaning of the WF, but ostensibly it saves unitarity. I'd also call into question the physical meaning of the Event Horizon bc how is "can't get out" a local observable? But what do I know? Um, anyway, this still leaves us with only a possibility of unitarity, not a proof of it. Certainly not, as Dr. Collier would demand, an experimental confirmation of it. Strictly speaking, I don't believe pure quantum states exist at all. But let's save that argument for another day. If ever. P.P.S. AdS isn't a theory of gravity. Bill Unruh pointed out, I've never heard other physicists refer to it in public or within my earshot, that whether or not a wavefunction defined on a manifold is pure or mixed depends sensitively on the manifold's shape. He meant this only as a simple example to illustrate how it might be that generically the universe as a whole might be in a mixed & not a pure state. As for what the shape of the universe really is, observationally, we can't quite discriminate between 3 possible types of shape we'd like it to be: a sphere, a hyperplane, or a hyperboloid. If its curvature overall is positive at large scale, its shape is a "sphere" & we call that a deSitter geometry. OTOH, if it's negative, that's an Anti-deSitter geometry. The advantage of hyperbolic is it has this property: M.C. Escher: Circle Limit IV https://mcescher.com/product/poster-large-circle-limit-lv-bl-w That is, it has infinite extent packed into a finite area. Its edge is literally the sum of its interior. Then, when we superimpose a gravity theory into the interior, ie, the "bulk", a direct analog quantum field theory emerges on its boundary, ie, at the edge. There's a dimensional reduction argument (or that's what I think I recall) that the Standard Model might actually live in a 2D subspace. Where it would be further reduced to a Conformal Field Theory. That's quite a simplification, if true. Anyway, AdS/CFT is between a 4D AdS gravity theory & a 3D CFT. Our realistic expectation is that our universe at large scales has positive curvature (lives on a deSitter manifold). If so, there's no reason to expect it to ever end. The AdS/CFT relies on arguments that we can reach the edge in finite time. Those don't go thru. And, I guess, Footnote: I forgot one of my textbooks. The Principles of Quantum Mechanics, by P.A.M. Dirac, originally printed in 1930. The latest printing may well be a garbage book. But the text is a good book. Historically important book that taught the then-latest quantum mechanics to physicists of that day. Dr. Susskind hoped we'd love it & some of us didn't. The living-room physics club I was in bogged down because one of us was quite mathy & he couldn't stomach the lack of mathematical rigor. That's ironic, as too much math rigor had made the book hard for physicists back then. Anyway, I'm mathy & I'm not too finicky about a vector space being real or complex, the distinction between inner product & dot product, between a "basis" & a "complete orthonormal set". I know which is which, and as long as I'm not confused, it's OK with me to use the terms interchangeably until the distinction matters. So, I'm with Lenny. If you get a chance, see if you like it. If not, it's fine. Me, I loved reading Maxwell's earlier papers where he seemed as confused as I was learning electromagnetism. That is, he was learning a subject nobody had a good handle on until people like Faraday had poked & prodded it to death. Faraday had had an intuition which fortunately panned out, & he chased it doggedly. Good for all of us that he did, & that he was right enough about it. Anyway, Maxwell's confusion pleases me no end. I'm nowhere near as smart as those guys, but when you're skirting the edge, you're like a child, you just don't know stuff. And kids can get things wrong in hilariously smart ways. Confirmed: Amazon 2013 paperback $30 new. 2023 paperback $18 new. Reviewer says (Amazon doesn't make clear which edition reviews are of, but look at this): Poor font on book Reviewed in India on August 3, 2023 Verified Purchase This book look like someone print at home and sell online. Very poor font black ink is missing in so many letter. Very bad, hard to read." One reviewer shows us a page with a library stamp in Greek. One review shows text fills only a small portion of each page, like it was photoreduced. Seems like what's at work here is out-and-out theft. Obviously, check it out from a library. Procure a used copy of an older edition. Pay attention to the cover. Poor copy quality may stand out more on the cover than inside. Thank god for free markets. /s Happy reading, whatever you read this year. Good luck with your day job. We used to call that biz, "Bilking the government". I mean grant factories. But we were in favor of it. They do a lot of good. They're more relevant than ever, but not enough of the public knows that. (P.)^N S.: Yes, LS is human. RPF befriended a young LS. LS remembers it like Ralph Leighton. I can resist the temptation to take LS confirming RPF bros dreams as gospel. Is LS a good talker? Well, not in terms of knocking my socks off. But LS knows who he's talking to & is low key enough to make his audience feel comfortable. Lots of physicists enjoy working with LS. My impression of RPF is that he could be very nice at times & awful at other times. I imagine a wide range of reactions to that. But, I'll have to wait to confirm my theory until the next iteration of the Big Bang. Seeya there!
mykey6375
2025-02-07 07:38:17 +0000 UTCP.S. Nate, I think one of the confusing things in the way we talk about quantum systems is we say we extend a Hilbert space to include "the environment" or say that a bound state shrinks the Hilbert space of an atom or molecule to explain why latent heat is less than classically predicted. When the whole universe is already included, there's a unique Hilbert space that can't be enlarged & we can say any missing states are hiding somewhere as entanglement. Thus the claim is at least more plausible for the cosmic wavefunction. Personally, I'll accept the WF of the universe for the sake of argument, but I don't "believe" in such a beast. Lenny's actual physics book, the thin, "black hole information" primer meant for physicists, implies otherwise, & Lenny is of course way more of a physicist than I'll ever be.
mykey6375
2025-02-07 06:39:11 +0000 UTCthanks mrkey, great comment. I definitely dont know quantum mechanics, I had no idea quantum mechanical entropy was constant. I guess as you said its a different kind of entropy. people always say quantum mechanics is weird, but I think your comment is the first time it ever really struck me how weird it is. Im an engineer and I work with classical entropy and classical thermo, so an entropy that is constant is bizarre. completely confused but I love your comment
Nate Robertson
2025-02-07 05:04:32 +0000 UTCRight. But I wouldn't expect direct observational confirmation in far longer than our lifetimes. We'll do what we're doing now. E.g., the object we took a picture of is a black hole because we calculated its mass & it's big enough to collapse itself. In theory.
mykey6375
2025-02-07 02:48:14 +0000 UTCHi Nate & Dominik. Yes, Nate, Hawking's reasoning that information is lost is despite the Hawking radiation. Because of the Hawking/Bekenstein area law, the physical ie quantum information of a black hole is equal to its surface area (in some units). If it evaporates away then all of its information must be in the Hawking photons. But the no hair theorem proves that in quantum terms, there's less information in them than in the original matter that the black hole was formed out of (the star that collapsed). That's because the quantum state "disperses" over time. The slang for that is it "thermalizes". The photons are all radiated away "randomly" ie not dependent on their past history. This is another way of saying the process is irreversible. You can't get back the original wavefunction of the star by running time backwards. Any irreversible process is a total blockade to that. The laws of quantum mechanics are all reversible. This is a contradiction. Quantum Mechanics is dead. Uh oh. Dominik is right that there are many different kinds of entropy. According to molecular theory, only the entropy as defined by quantum mechanics is made up of "microstates". All others rely on "macroscopic" measurable quantities that we are at some liberty to make up at our convenience. Like, the ideal gas law PV=nRT only relies on an extremely simplified model of the gas particles. Consider what happens to the entropy of a gas mixture vs. when we don't distinguish between two kinds of gas. We change what we mean by entropy. So, the heat death example is perfect. That's a classical thermo take. Quantum mechanical entropy is, believe it or not, completely constant, once we take entanglement into account. That's ridiculous, nonsensical, violates second law, has got to be poppycock. Well, depends on what the meaning of "is" is. Ha ha. There's something like quantum thermo out there, but it's kinda outside our scope at the moment. That, & I don't recall much of it, offhand. :)
mykey6375
2025-02-07 02:30:20 +0000 UTCI think we can individually have a negligible effect on the English language. My suggestion is to live in the time & place we occupy in the world & do the best we can within that boundary.
mykey6375
2025-02-07 01:54:20 +0000 UTCYou are entitled to your opinions. And like proper time is invariant, you're always correct. In a partial defense, I think the titles & cover work were influenced by bad advice. Of course, that is my own opinion.
mykey6375
2025-02-07 01:50:13 +0000 UTCThat kind of thinking is never the right reason not to reread a book.
mykey6375
2025-02-07 01:46:24 +0000 UTCIt's important to say that the "time slowing down" isn't from the point of view of an infalling observer. Proper time = subjective time, & the only way to actually stop time from the POV of a subjective observer is for the "observer" to be a photon. The key insight highlighted by this line of thought is that there are simply "places" that are "out there", "in existence", that can never be "seen" by any means from a disconnected section of "spacetime". The reason Hawking photons even if the "information" has simply sat at or near the horizon for forever, don't solve the information loss problem is because the quantum state of the near horizon quantum background (vacuum) "thermalizes" meaning its history gets cut off. The meaning of "black holes have no hair" is that the exact equivalence to a classical thermal equilibration means the information is truly lost. That's why it's a "paradox". That definitely isn't an allowed outcome in a pure quantum system. No one has a satisfying answer to it. The different physics observed from different gravitational reference frames goes by the name "black hole complementarity". The main reason it isn't seen as a definitive resolution is mainly because it's sort of a tautology, so doesn't reveal anything new & fundamental about gravity or quantum mechanics. Even many important questions about black holes that we'd like to have answers to aren't addressed by that at all. Like, how can we find out more about how a black hole forms? What happens to stuff if it reaches the singularity? At the end of the black hole's life, it has totally radiated itself away & gone POOF!, where did the information go? What's its wavefunction now? I mean, including all the Hawking photons. So-called BH complementarity breaks down, can't remotely explain what happened.
mykey6375
2025-02-07 01:45:05 +0000 UTCWell.. it sounds like the answer is closer to, "the event horizon can change size" from our perspective?
Doug Dee
2025-02-07 01:28:36 +0000 UTCNo, it's a paradox because at the quantum level, we are talking about physical microstates ("quantum quantum quantum") not subjective macrostates, when we say "quantum entropy". One way to look at this rule of quantum mechanics is to define the initial entropy of the universe (cosmic wavefunction) as equal to 0. And then by unitary evolution, which includes a term called "entanglement entropy", the total entropy of the entire universe will be identically 0 forever. Versus, even if we include all the Hawking photons that have escaped, the total entropy of the BH + radiation system decreases because the photons are emitted "at random" which is equivalent to having no history, ie, do not contribute to the overall quantum state. A partial resolution of the paradox comes from postulating that "scrambled" could be not quite the same thing as "random". But conventional quantum theory doesn't treat an emitted photon as having a history. String theory might be a possible out. Maybe. Edit: P.S. In the usual story of where Hawking photons come from, pair production in the vacuum, a photon by its lonesome poofed into existence out of the vacuum from nothing has no prior history. We might claim something changes in the vacuum as a result, but that would be a strange new take on quantum theory, very much unconventional. Hidden properties of the photon itself would also be against the mainstream belief system of quantum mechanics.
mykey6375
2025-02-07 01:08:03 +0000 UTCMass and energy are "equivalent". When we say a photon is "massless" we mean its rest mass is 0. But its energy is always equal to its frequency (in some units). Which is equal to a "mass" according to the formula E=mc^2. When we do the calculation, a typical Hawking photon's energy is incredibly low, meaning its wavelength & so its "size" is many times the black hole's size. That photon, the one that escapes, will appear to be spontaneously spat out of empty space far away from the black hole's event horizon. And it'd be indetectible both because of its low energy & because it's far colder than the CMB is now. Just wait a few trillion years, though, then whatever's alive then might be able to pick it out & recognize it as a deviation from the utter blackness of deep space. Right now, we can pick out galaxies in any direction we point our telescopes at. Hopefully, by then there'd be one black spot to pick out a Hawking photon in. There's no other way to lose mass than by emitting a particle. And there's no way to emit a particle without losing energy. Which is equal to a mass.
mykey6375
2025-02-07 00:45:42 +0000 UTCNo, because the event horizon grows & can shrink. Its surface area is directly proportional to the black hole's mass. Its radius also grows & shrinks according the usual formula that area of a sphere equals 4 pi R^2. Also, please think about how we might be able to "see" the size of the black hole's "disc". This is not a "gimme" question. If you want to bend your mind even more, think about the definition of the event horizon: It's where escape velocity is the speed of light. That is, in GR-speak, no world line from that spot can intersect the outside universe. In a little more detail, it may help you to know that at low curvature, most of the effect of curved spacetime in usual astronomy situations & altitudes would be on the time coordinate. This is because units of time are multiplied by the speed of light, which in familiar units is pretty big. We can hold our distance units fixed, practically. We wouldn't really expect to be able to see a black hole's disc change appreciably unless the black hole was smallish & it's eating something else kinda big. For a supermassive black hole, the curvature at its event horizon is almost "flat spacetime". For a collapsed star black hole, there's more curvature, but that's where we would still expect the main result to be "flat space", ie mostly time dilation as opposed to spatial size. And now I can just quote you this Q&A explainer: Does Time Stop In a Black Hole? https://profoundphysics.com/why-time-slows-down-near-a-black-hole As one moves closer and closer to a black hole, the passing of time will also slow down more and more. So, does time therefore stop as one falls into a black hole? Time does stop at the event horizon of a black hole, but only as seen by someone outside the black hole. This is because any physical signal will get infinitely redshifted at the event horizon, thus never reaching the outside observer. Someone falling into a black hole, however, would not see time stop. [What I meant by "flat" is that the tidal forces are close to imperceptible. If the world line of a photon gets bent backwards, that is some kind of curved, obviously.]
mykey6375
2025-02-06 23:47:14 +0000 UTCI've had this question and gotten odd answers to it for years. I think it was in Errol Morris's documentary abut Hawking, "A Brief History of Time" - (it might have been something else) - It explains that if you were to go into a black hole, (ignoring that you would be torn to shreds), you would approach the black hole, and cross the event horizon and everything (time-wise) would seem the same to you. BUT, someone looking at you from Earth, would see you right on the event horizon....... forever.... and they would never see you go in. So my question is, if from Earth, nothing ever seems to cross the event horizon, the "stuff" is stuck there forever, is it true that from our perspective, we never see a black hole grow.. at all.. "ever."
Doug Dee
2025-02-05 07:08:07 +0000 UTCmmm no I get that its thermodynamic information, which is different from day to day understanding of information - though I will point out the use of the word comes from our day to day understanding. thermodynamics does not require this I think, certain quantum theories like no hiding and no deleting do. which Im skeptical of at high energies or extreme environments or long periods of time. I dont think we should mix up information with energy as a general concept because they arent the same afaik. hawking also posited that black holes destroyed information. its only certain quantum theories that arent okay with that. There's no contradiction if you allow information to be destroyed. only quantum theories disallow that. now, why exactly no hiding no cloning no deleting are treated as absolute, I dont know. I could be wrong, Im not a physicist, I dont know QUANTUM mechanics. but Im just saying, ignorantly, maybe they're wrong. lol.
Nate Robertson
2025-02-05 02:13:48 +0000 UTCSo the lipstick works with the whole "not Chucky" look It's like a fresh scar. So this is just an extremely early Halloween special. Or a reflection of how things are going so far this year. Either way
Novus
2025-02-04 23:52:58 +0000 UTCIt's going about as well as we expected. Genuinely, thanks for asking. I was unexpectedly laid off last week, which... Well I guess here I am, you know? It's so great that we have communities of sanity like this, and I'm glad to see you join nebula. Might be time for me to get a subscription (when I have an income again)-do you have a creator code that I missed somewhere? As a practical step that has been helping me more or less stay sane, I have been getting active with an activist group called Climate Changemakers for the past couple months. It's been really helping my mental and emotional state, actually doing Something. It's a nonpartisan group, low pressure and focused on small, manageable actions that actually help the situation. With the federal disaster, the focus has shifted to state and local action to still progress climate goals. The events are generally weekly Hours of Action basically just to dedicate one hour a week toward Doing Something. It's really helped me personally at least take the edge off the feeling of helplessness.
iceisarock
2025-02-04 06:11:08 +0000 UTCcan someone explain to me how that pair of spontanously generated photons take away part of the black holes mass when one of them is emited as radiation if photons have no mass?
dreamfyre
2025-02-03 23:38:26 +0000 UTCRegarding jobs, here is an interesting email from the NSF. The bottom line is people are pushing back against Trump's attempt to arbitrarily just shut down R&D. This is good news but only applies to money already awarded, when it comes to future awards that is completely under the control of the executive branch: From: grants_conference@nsf.gov Subject: Message to the NSF PI Community Dear Colleagues; On Friday, January 31, 2025, a Federal Court issued a Temporary Restraining Order (TRO) directing Federal grant-making agencies, including the National Science Foundation (NSF), to “...not pause, freeze, impede, block, cancel, or terminate... awards and obligations to provide federal financial assistance to the States, and... not impede the States’ access to such awards and obligations, except on the basis of the applicable authorizing statutes, regulations, and terms.” Although the language of the TRO is directed at State institutions, the Department of Justice has determined that it applies to all NSF award recipients. You can review the TRO here: https://nsf-gov-resources.nsf.gov/files/TRO-NY-v-Trump-1.31.25.pdf In order to comply with the TRO, the NSF Award Cash Management Service (ACM$) system is available for awardees to request payments as of 12:00pm EST, February 2, 2025. This message is also available on the Executive Order Implementation webpage. Please check back regularly as we add frequently asked questions (FAQs) based on community feedback. Sethuraman Panchanathan Director
Michael DeBellis
2025-02-03 19:42:16 +0000 UTCSo, perhaps this is naive, because I have no understanding of black holes outside of pop sci books. But, even if the holographic principle doesn't make a lot of sense in general, isn't it sort of the 'natural' resolution to this problem? For instance, it's my understanding that for real black holes, from our perspective outside, nothing ever actually makes it 'into' the black hole. It would take an 'infinite' amount of time to do so, because time starts moving increasingly slowly (relative to us) the closer things get to the event horizon. So, to us, it _actually_ looks like everything 'in' the black hole is at best on its surface, even without some kind of general holographic principle. I could swear I've heard mention of this before, too. Like, some supposed correspondence between Hawking radiation of an 'idealized' black hole and the behavior of actual matter very near to the surface of a black hole. Then there isn't even an appearance of a paradox, because the actual stuff near the surface of real black holes will differ, and contains the 'information.' Eventually the information escapes having never really made it 'inside' the black hole, because nothing ever does from the perspective of someone who isn't falling into one. But of course, as I said, I don't have any genuine understanding of black holes.
Dan Doel
2025-02-03 18:09:49 +0000 UTCThanks for asking (how's it going)... Terrible! I've done some research in the past for NSF and NASA related to using computer science and AI for climate change research so I'm subscribed to a bunch of mailing lists for federal research. Ever since we handed the inmates the keys to the asylum I've received message after message about this or that program are cancelled or on hold. But far worse than any impact it has on me what is coming in terms of the economy, mass deportations, climate obstruction, and the hope for real democracy in the USA, it makes me depressed. But I think worst of all is what the election says about how this nation is still so much more racist, sexist, and filled with greedy short sighted idiots than even a cynic like me thought. So sorry about your job. For what it's worth, I think you will be fine even if you lose your current job. I know easy for me to say. But you are both extremely intelligent and know how to communicate and that's a rare combination. I voted for the Black Hole thing because I wanted to test my (very limited) current understanding about what the "Information Paradox" is and correct/expand on it. I think that my understanding was more or less correct. It is one of those paradoxes (there are several of these in advanced logic as well) that aren't really a paradox. As I understand it, the reason it is a paradox is if information is really "lost" that means entropy decreases. But just because information is inaccessible to us isn't the same as saying the information is "lost" in a way that conflicts with the law of Thermodynamics that entropy only increases.
Michael DeBellis
2025-02-03 17:34:10 +0000 UTCI own Black Hole War (hardcover courtesy of the thrift store I think) and I read it something like ten years ago and have retained not a thing. Thanks for saving me from a reread, lol. Excited to hear about disaster movies! And solidarity about all the.. y’know. It sucks.
genessa
2025-02-03 04:44:03 +0000 UTCI'm sorry for the everything atm. I hope you all in the US get through this insanity with the least harm possible. Great to see you coming to Nebula and I'm certainly staying here on Patreon in any case.
Timonsku
2025-02-03 04:24:02 +0000 UTCI'm just at the beginning but I'm really excited that you're joining Nebula.
Lawrence Anderson
2025-02-03 04:15:12 +0000 UTCwhat's your Nebula URL?
Anthony
2025-02-03 01:36:07 +0000 UTCIt is terrible out here, but thanks for keeping going on. Maybe if we still together we can make it out of this shit
Cras
2025-02-02 20:55:09 +0000 UTCInformation - just like bat, date, or bark - has multiple meanings and the meaning depends on context. What you're describing is information in casual sense of the word: some data that can be stored or deleted as needed. I'll use "" below for oversimplifications but I hope my explanation will be understandable. Information in the context of video is about thermodynamic state of system at different points in time. Thermodynamics require that whatever "state" is absorbed by the black hole is still inside, even if "modified". When general relativity describes black holes, it posits that there's only "absorption into nothingness" since nothing can be retrieved from the black hole. This is the contradiction which is the core of the paradox. Hawking's solution is "slow emission of state" from the black hole at its edge (the larger the black hole the slower the process).
Dominik Dalek
2025-02-02 20:48:46 +0000 UTCQuarks are made out of sparks, thereby unifying the fundamental forces into one electronuclear force (gravity is emergent)
Shawn D
2025-02-02 13:30:51 +0000 UTCSorry for this mad situation. Hope it works out for you and everyone. Glad you've joined Nebula. I was wondering why you hadn't, and whether they might actually not be a good deal for the creators. Now I'll definitely keep the subscription.
gkoz
2025-02-01 23:04:04 +0000 UTCSending empathy as someone else working in the federal space. This hostile takeover of the federal workforce is going to push out many of my teammates who are extremely hardworking and dedicated civil servants and it's heartbreaking to watch. Thank you for continuing to make excellent videos. Independent creators are going to be so important to combat the systematic censorship of our public institutions. Hang in there and be kind to yourselves.
Austin Schey
2025-02-01 20:51:35 +0000 UTCDo you plan on uploading any videos that are truly exclusive to Nebular or will it just be regular + patreon videos?
Brock English
2025-02-01 20:47:29 +0000 UTCim listening to Heroes orchestra while playing manor lords https://www.youtube.com/watch?v=BGWvrHEWq4Y...its a nice relaxing experience
Josko Franic
2025-02-01 19:19:10 +0000 UTCGlad you're on Nebula now, I really like watching videos there just because they never have ads. I don't think your channel is visible there yet, though, please post a link to Patreon when it's up!
Tobasco da Gama
2025-02-01 18:17:56 +0000 UTCThis is precisely the time to find deeper courage & ask bigger questions about the system you grew up in & the gaping flaws in its mythologies. Move beyond the expectations you inherited that have now evaporated & discover what you yourself should truly believe in. There is a better world to be made, by those of us with true courage, beyond the ideological chaos & false alliances forced on us in the course in the last quarter-century. This moment holds more promise than is obvious.
Max Sonthonax
2025-02-01 14:07:50 +0000 UTC🎩 🕳️
Max Sonthonax
2025-02-01 14:02:43 +0000 UTCWe just erase the first century from the history books and no one talks about it any more. It's a sacrifice, but a worthwhile one to avoid this confusion
Robert Bieber
2025-02-01 14:01:57 +0000 UTCNo. The logic is clear: follow it. No hand-holding needed.
Max Sonthonax
2025-02-01 13:59:09 +0000 UTC"Black Hole Wars" is at least as bad as you thought it might be - probably worse.
Greg Hellen
2025-02-01 13:53:47 +0000 UTCbut then what do we call the first century?
Bart Luyckx
2025-02-01 09:43:09 +0000 UTCIt's going bad, Angela. It's going bad. But it's a bit better when there's a new video to watch!
Ryan
2025-02-01 06:24:11 +0000 UTCMeteorology dropout here. I wanna know more about the weather modeling. Please someday talk about weather modeling.
Kate Hamra
2025-02-01 04:25:44 +0000 UTCI really hope the situation in the US "stabilizes" a bit. Glad you joined Nebula. I can't find you there, though. Nieither "acollier", nor "angela", "collier" or "angela collier" or "astro" yield any channel results with your channel. I might hang out for your next live stream and I might be able to help with debugging the technical end of your stream (after all, it is partly what I do for a living). I saw it posted on bsky, but really did not have the time to join. EU can be tricky for things like that. /edit: Funny story about Schwarzschild radius. When I learned about it in high school. Because it is black-shield in German, for the longest time I thought they named it because it like that because that's where the black hole turns black. But of course it was they named it after a guy, and also it's not the radius where the black hole turns black (photon sphere and also rotating black holes and a ton of other things in your video of course). If you need help pronouncing ancient German family names so much in physics (and chemistry) is named after, just ask :D
Stephan Wimmer
2025-02-01 04:18:47 +0000 UTCoh yeah also I would love to see you and jenny nicholson do a collab on star trek or twilight zone. I dont know if youve talked, I assume you have. but you should shoot her a message. everyone agrees. I spoke to everyone and they said "yes that should happen"
Nate Robertson
2025-02-01 04:04:57 +0000 UTCcongrats on nebula! i subscribe to it but mostly still watch everything on youtube lol. things are so bleak right now! anything you can do to get through the day is morally permissible in these times. Hope you're all still hanging in there. i'm a trans woman and it looks like i might have to start the process of getting divorced, so there's a lot of bad energy around me at the moment. i'm grateful for my support network. i recommend checking in on your trans friends, boost some gofundmes, anything more than telling us that we're valid. i liked the topic of the video and felt that i was understanding it well at the points it was asked about (eg ~the 17th minute i think?). i really liked the rant about print on demand books because they are garbage quality!!!!! i hadn't even thought about returning them, but i have hoarding tendencies towards books i think. but it's so hard to know if i book is going to be print on demand when you're buying it! outside of buying hardcovers and academic presses it feels like a big gamble buying books online these days. grateful for this video in the current moment!!!
Jack
2025-02-01 03:13:41 +0000 UTCMixing up the nineteenth century and the nineteen hundreds is an extremely relatable moment. Can we just start naming the centuries by the first two digits?
Robert Bieber
2025-02-01 03:01:07 +0000 UTCThank you for this! It's the best explanation (at a non-math level of course) that I've ever heard. Please keep explaining things this way. I love all the caveats and admissions that we don't know the full answers to things. It's refreshingly honest.
Jeremy Reimer
2025-02-01 02:47:26 +0000 UTCNebula👍 Livestream👍
Bryn
2025-02-01 02:45:32 +0000 UTCThis was really interesting for me! Sorry you're feeling stressed - I would be if I was a US citizen right now. Let us hope that in the fullness of time the data centres now being built will be put to better use :)
Leo Kyle
2025-02-01 02:16:39 +0000 UTC>He actually said that 20 years ago, and you could have done that 20 years ago with photoshop and LSD. love this
Nate Robertson
2025-02-01 02:13:39 +0000 UTCAlright, so here's my take: I watched the whole video, and from my “idiot” perspective, the idea that black holes can’t destroy information seems tied to a physicists’ belief that information must be preserved? For instance, if you compare matter and antimatter black holes as you said, you should, in theory, be able to tell them apart; otherwise, it seems like the universe is deleting information—which apparently isn’t allowed? But honestly, I think information gets deleted all the time. When I'm editing videos, I often lose color or sound details by compressing files or saving in the wrong format. In the grand scheme, entropy is always working, gradually erasing everything until, at some unimaginably distant time, everything might just collapse into a uniform state where all data is lost? No? So why shouldn’t black holes destroy information? Maybe they're just nature/entropy's way of converting a high-quality .tiff into a compressed .jpg—a really efficient method of deleting data. Theyre just speeding up entropy. esp if hawking radiation exists. I know I’m probably missing a lot, and if Angela reads this, she might say "this idiot doesnt get it all" (true) but that’s my uneducated take. Susskind clearly outclasses me in physics and math(the most physics Ive done was orbital mechanics in engineering, which I did very well in and got 100% on the exam - but thats childs play to physcists) yet his ideas and presentation still give me some Kaku vibes. like medical doctors who receive so much education they start to mistake their own intution for their own education and start saying nonsense like inject ivermectin or whatever. edit: okay heres a better summary of what I think. I think of the heat death of the universe as ultimately being the information death of the universe, if there's information that is tangible between points that is a state that entropy can erode, no? if no heat, no way to "discern" information or action to occur between different states. so... information death. therefore information must be destroyable, ergo blackholes can destroy information. if information cannot be destroyed, heat death cannot be real? no? Im probably completely and utterly wrong ---- looking forward to disaster movie video. deep impact and armageddon scarred me as a child. I was scared of the night sky because I was always afraid a comet was going to come and kill everyone. it was totally irrational. all my worst nightmares have been asteroids killing everyone. also aliens. I've never been afraid of ghosts or monsters, just aliens and comets lol. I actually got to work on the Canadian NEOSSAT and then operate it at the Canadian space agency, I was so thrilled for a mission that was about detecting near earth objects. the idea was spear headed by Alan Hildebrand - the guy who definitively proved an asteroid killed the dinosaurs. meant to find asteroids (like 2024 YR4) but neossat was a total disaster, (rush job, poor management) the camera doesnt work that well, and asteroids have a very high magnitude. so neossat cant see neos (rofl) now neossat just looks at exoplanets and other spacecraft. Alan called it a failure, it basically is. but america is working on a new one called NEO Surveyor. also Ive been listening to lectures about the maya, and it seems like the idea that they thought 2012 was some end of the world date is a total misunderstanding. the lecturer I was listening to, ed barnhart, says it was obvious that was never the case and, Im not gonna repeat the math, 2012 was not ever the real end of that long count? --- anyway loved the video. cool youre on nebula. I joined nebula for lindsay ellis years ago, but I always forget Im paying for it lol. cheers. sorry I wrote so much.
Nate Robertson
2025-02-01 02:03:41 +0000 UTCWell done, I could see your anxiety with this and it seems like a difficult task at a difficult time. You also hit on my skepticism of the framing, and the allurement of the Holographic solution because it is aesthetically interesting to the general population. Brings back memories of the far end of the popular science allurement from that time, and Michio Kaku saying “In 20 to 30 years we’ll be able to upload information directly to your brain. You won’t need to go on a vacation you’ll be able to upload the memories of one.” He actually said that 20 years ago, and you could have done that 20 years ago with photoshop and LSD.
Tony Peluso
2025-02-01 01:53:45 +0000 UTCBrighter days ahead but we are all in danger of losing our jobs. Either they'll try to cancel your funding or they'll * the whole economy. Just have to be ready to roll with the punches while fighting an uphill battle
Curtis Blake
2025-02-01 01:53:08 +0000 UTCIt took something as horrible as the Great Depression to put us on a progressive path. This latest insanity is at least as bad as that. I'm hanging my hopes on that thought and whistling past the graveyard. Thank you for your awesomeness.
Joel Files
2025-02-01 01:47:23 +0000 UTCWhat's your Nebula URL?
Anthony
2025-02-01 01:46:31 +0000 UTCit makes sense but teach us tensor math anyway
Christian Siebott
2025-02-01 01:18:24 +0000 UTC❤️
Jeron Knight
2025-02-01 01:15:31 +0000 UTCneeded this tonight ❤️
sampled tms
2025-02-01 00:52:27 +0000 UTC
