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The Big Bang should have made cracks in spacetime–why haven’t we found them? (arstechnica.com)
74 points by LinuxBender 11 days ago | hide | past | favorite | 87 comments

So we’re in a situation where we strongly suspect that there should be cosmic strings riddled throughout the Universe. And yet decades of direct and indirect searches haven’t found any. At all. We’re left with two conclusions. Either our understanding of the physics of the early Universe is way off base and cosmic strings aren’t nearly as generic as we think they are, or we’re not understanding how cosmic strings manifest themselves in the modern-day cosmos and our observations are missing something.

I think it's safe to say our understanding of the physics of the early Universe is way off base, and by early, I mean a few seconds old. We're going to have to unify GR and QM before we have a shot at understanding the physics of the early Universe.

Because the maths of physics was modelled based on what we could observe from the various states of the univers. Outside of those contexts, it is only theorical exploration and does not tell us anything, until it is, aka the experiments say otherwise.

This is your annual reminder that The Big Bang is just one of many valid cosmological models.

Wait, which models don't envisage a period where everything is hot enough to unify the fundamental forces? If that happened, you need some mechanism to let the universe cool off without producing these kinks...

I'm under the impression you know more about the subject than I do :)

I'm mostly replaying what I learned in Penrose's Road to Reality...it's possible that _all_ current cosmological theories predict "cracks," though given the sheer number of models out there, that would surprise me.

I'm certainly a layman. But it seems that the predicted strings are supposed to have been caused by the hot-dense early universe cooling off in a particular way, rather than anything to do with how the hot-dense state happened. So it's not clear that making the universe cyclic helps you solve the problem. A much simpler solution would be just that the behavior of the early universe somehow prevented them forming or made them much rarer than we thought.

There's renewed debate about the Big Bang theory now that JWST is beginning to return images of earlier times than we've seen before.

Eric Lerner has been making the case that there was no BB for a long time now.

I think these are valid criticisms and he's now updated them wrt to JWST


I've seen this brought up, but I'm unimpressed with Lerner. He follows pretty slimy tactics, taking quotes by other cosmologists completely out of context to try to claim they're saying things that they aren't. For example, this discussion: [0]

It seems to me like he's a guy who has a theory he's held onto for decades and takes every opportunity to bring it up again. He tries to make it sound like there's new doubt, but the actual people that he misquotes deny they meant what he claims, and if you read the original quotes it's clear that he's cherry-picking. That's not to say that he's wrong, just that his arguments are very unpersuasive to me because they rely on misleading the audience.

[0] https://news.ycombinator.com/item?id=32475958#32476256

I don't think anyone at the JWST thinks so.



I don't think that article you linked is fair to Lerner though. Casting him as a pseudoscientific denier is a recognizable trope, but is incorrect by their own criteria:

- Published in reputable sources? Yes, well-published on this topic in journals and leading newspapers[scholar,wiki]

- Associated with a University, with related credentials? Yes, has a BS in physics from Columbia[wiki], some grad work at UMD. More importantly, he's a notable plasma physics theorist/engineer (most of his career and publications).

- Anyone else agree? Yes, he's following in Alfen's plasma cosmology[alfven]; Alfven is a Nobel Prize winning physicist who also criticized the BBT.

- Cited references? Yes, the video I linked is well-cited, e.g. the 16 failed predictions of BBT vs 1 correct. See 23m45s for citations of this claim.

- Follow the logic? Well, Lerner's video is pretty straight forward and extensively reviews the primary lit, but the space.com article is mostly a string of ad hominem, comparing him to "people who deliberately peddle anti-science narratives" and flat-Earthers, and that "the tactics employed in Lerner's article are classic misdirections used by science deniers".

Which.. is bad journalism but to me signals its own bias and likelihood he's saying something important. I'm very much looking forward to the next few years on this!



[alfven]https://en.wikipedia.org/wiki/Hannes_Alfv%C3%A9n, https://en.wikipedia.org/wiki/Plasma_cosmology

Just wanted to say that I like your citation method & will certainly be using it in the future.


Thanks :) switched to it recently to avoid renumbering after reorganizing text and helps as a mnemonic too!

Perhaps the entire universe is like a Game of Life space in which the observable universe has emerged as ongoing complex activity, with patterns of stable and chaotic oscillations forming emergent functional parts, which then interact and join to create more emergent functional assemblies now with more features to interact by, such as mass and gravity. This would explain the apparent expansion of the universe, as the observable universe could still be forming new ”massy assemblies” at its periphery, thus increasing the gravitational pull towards the outer limits of ”our bubble”.

I believe one of the possible reasons for the spatial defects, like cosmic strings, not being found could be that they've essentially stabilized over time which means the slight differences between patches of spacetime effectively mended and thus wouldn't leave anything detectible. But I do believe there's still some consensus that we should see some of these defects in deep sky observations despite this possbility.

Because the engineering team pre-optimized for that?

> And here's something wild: At those energies, there are only three forces of nature, not four.

oh ok

does this field just lack words to convey a shared concept?

I often see these language anomalies only in reference to physics and outer spaaaace. Its like a bad attempt at skeumorphing when different words should have been used from the start.

Like in this article “Did you knooow, this is so interesting, that space-time has cracks!? I know right! at these energy levels electroweak force (appropriately named) merges!”

Why are PhDs communicating like this? How does this article conveyed a shared concept (the point of language) to anyone except a few people that went to the same school? who is this for?


Physics concepts are notoriously hard to communicate in natural language. You need to see the math in order to go any deeper than "spacetime cracks."

I highly recommend Leonard Susskind's "Theoretical Minimum" course if you would like to go deeper, and see this fact for yourself: https://theoreticalminimum.com/

I'm actually reading his Black Hole War book right now and he does a great job of explaining things conceptually.

The universe doesn't really play nicely with human metaphors. That's why physics spends so much time deep in mathematics, because it turns out our metaphors don't line up with reality very well at all.

Or, alternatively, mathematics provides a really, really intricate set of interlocking metaphors that you can train yourself to use, but most people haven't. So anyone without the right training is left with a relatively impoverished understanding (including me!)

We need ~~priests~~ scientists who speak ~~Latin~~ mathematics to interpret what truth really is because none of the rest of us have been trained.

EDIT: I thought HN used markdown for comments, but I guess not. The double tilde is strikethrough in markdown.

I've taken math courses that were beyond me. This stuff is actually difficult, in ways that are probably irreducible. Once you get your head round a new mathematical tool though, it opens up others. But without that base understanding, that stuff would be incomprehensible. You can't jump over building understanding of the complicated underlying metaphors first.

It's like first encountering, say, computer programming. Until you've got the fundamental tools of loops, conditions, and so on, the whole thing can feel like incomprehensible magic. And that's a system that was designed by humans to be more-or-less comprehensible. The universe doesn't have to be!

This is the same reasoning that Roman Catholics use to justify priests that know Latin and have a Ph.D. in Philosophy (specializing in Aristotle and Thomas Aquinas). "Theology is actually difficult in ways that are probably irreducible."

My only point is that science didn't destroy religion. It just changed the titles of the priests (scientists), the priesthood (peer reviewed journals), and the holy books (Principia, etc.). The same claims to special knowledge and authority remain intact.

Okay, let's go back to before science. Your circa 1000AD village blacksmith has special knowledge and authority about handling metals that you don't, and he probably can't explain it to you in an afternoon. That doesn't make him like a member of a priesthood, he's someone with specialized knowledge that could train you, but it would take a while and you'd probably have to pay him for his time. He'd similarly dismiss uninformed speculation about how he could do his job better, because he's trained in it and you aren't.

There are lots of domains like this that are much older than science and older than the Catholic Church. If anything, systems like the Church are like guild systems, rather than guilds being like priesthoods.

Science certainly is a bit like guild systems of old- lots of specialized jargon and training, mentorship, internal hierarchies, etc. But that didn't come from the Church, that's just the stuff that seems to spring up around specializations.

This may reflect the social nature of science and religion.

What it fails to reflect, however, is that religion is fundamentally rooted in revelation or inspiration (further conveyed, transmitted, and applied through authority), whilst science is based on observation and empirical evidence, and based on experimental validity rather than authority.

Neither is of course a pure instantiation of these general descriptions, and the structure of scientific institutions, education, and accreditation is of course strongly influenced by religion (with the University itself serving as a training vehicle for both).

Latin was adopted by the priesthood largely for historical reasons (the Roman Catholic Church originated in Latin-speaking Rome), and technical ones: books were ruinously expensive and it was far more practical to bring priests and scholars to the text, by teaching them to read and write Latin, than the text to the priests in the vernacular, at least until Gutenberg and Luther.

Maths is used in the sciences for the reason that it efficiently, accurately, and usefully communicates quantitative relationships and predictions.

Where Latin emerged externally and was adopted by the Church, much modern scientific maths was created in the service of science, with the highly notable case of Newton (and Leibnitz) inventing calculus in the service of physics coming to mind.

The parallels you note ... seem less useful and significant in this light.

>We need ~~priests~~ scientists who speak ~~Latin~~ mathematics to interpret what truth really is because none of the rest of us have been trained

No, we don't. Most people don't really need to know advanced physics. It's not like the knowledge will save you from eternal suffering, it's just interesting to some even if they have a shitty grasp on it all.

We need educated teachers to train engineers so they can use the "truth" to develop new technology.

Most people don't need to know advanced physics. We just need to follow the science, right? We can trust them because they are authorities with special training!

I follow them by using my phone to type this message to you wherever you are in the world minutes after reading your message. I don't understand how most of the parts work to send this message, but I know that there are many scientific principles involved I could learn.

I don't need blind faith in them. And they aren't hiding the information from me, I'm too lazy to spend the time necessary to learn it.

PBS Spacetime did a video on this recently https://youtu.be/Thw43hzXlDA

Well worth a watch!

Thank you! I have looong time looked for so good explanation.

So the right answer is that large cracks are not too numerous, and fortunately you will not find such artifact under your bed.

Even more - if I understand right, they are fragile, and cannot survive in places with high gravitational wave activity, like galaxies.

So we should search them in old voids, where they only trouble each other, and nothing else intervene.

This is acceptable start point for research, but with huge drawback: this assume very expensive research, because only largest telescopes (or latest gravity wave detectors) have good chances to detect anything.

Because the simulation maker patched those bugs. :)

From the ignorance, I don't think that the problem is why. The problem is how?

How we could find that the light that comes from star A is ... two minutes or one week or one decade delayed respect to the light received from star B? We automatically would convert any anomaly into more distance to earth. This distances could be just wrong and we would not know it.

Tired light theory is quite testable! It's failed.


If tired light is due to light absorption and remission with matter, it's falsified. If light fundamentally increases in wavelength due to travel over spacetime, it is not falsified.

I don't see the connection between that and what OP said?

I mean that distant galaxies are both definitely distant and definitely getting further away, and that's been measured and tested in lots of ways. Tired light is one proposed alternative to the expanding universe cosmology that's failed.

> distant galaxies are both definitely distant and definitely getting further away

That doesn't seem to conflict with what the OP said.

> Tired light is one proposed alternative

But not by the OP. I don't see how your comment relates.

If light were delayed we would know because the triangulated distance wouldn't match.

Was there space or even time before the big bang?

Didn't the big bang create space and with that time?

The cracks are supposed to have occurred in the first few seconds after the Big Bang, when spacetime would already be a thing.

When they can't answer that, it's about as credible as religion.

Actually, it's the other way around - if they answered it, they wouldn't be credible. The idea that you can't have any reliable knowledge without being omniscient is fundamentally denying the concept of acquiring knowledge, and science is our best process for acquiring knowledge so far.

My own belief is there is one universe, it is cyclical, and just is. No beginning, no end, just cycles between states.

There is no big bang. There is a minimum size state that could resemble a big bang.

> The Big Bang should have made cracks in spacetime–why haven’t we found them?

As the song says: We tried to look but they were gone.

Proof that we are in a simulation, not all details are accurately or correctly simulated.


Or, as many people since ancient times have believed, that we live in a universe created ex nihilo by a being capable of doing so…

Which very well could be a simulation on some god's computer :^)

The fact that things are not perfect or correct seems to me like an argument that it's not a simulation. In other words, I'd be suspicious if things are too "perfect" from our primitive primate intelligence.

It's just a simulation with geometry, physics, detailed textures and ray tracing.

I think we also have lazy evaluation, heuristics (wave-particle duality), out-of-memory killers (black holes, hawking radiation) and bandwidth limitations (speed of light).

It seems obvious, hopefully it's not going to kernel panic!

Well if that's true, then who created Jensen Huang?

Maybe black holes are those strings and cracks? Any point can turn to be a line if seen from the correct perspective.

As all came from the big bang all lines would radiate from the original point and travel with us all would be seen as points from our perspective.

Just an opinion. Probably stupid.

The article starts with a fictional tale because it's a fiction article.

I can't help but think the Mandela effect is an example.

Utter nonsense.


A person who grew up in apartheid South Africa

Agreed, for others: the "Mandela effect" is a fake idea that there are things that we collectively remember wrong because of various pseudoscientific claims. It's like a conspiracy theory.

It's called the "Mandela" effect based on the ridiculous claim that some people think that Nelson Mandela died in prison. That's absurd since it was after he was in prison that he did his most famous acts like becoming president and ending apartheid. The number of people that think he died in prison has to be vanishingly few.

For someone that grew up in Apartheid South Africa I can't imagine how insulting this would be.

People use it as an excuse when they remember anything wrong, just look at the subreddit and these ridiculous claims: https://www.reddit.com/r/MandelaEffect/comments/xg5a8o/meet_...

JJ McCullough did a great video on the topic: https://www.youtube.com/watch?v=aKujYkEmwWM&themeRefresh=1

I think your reply is a little too strident. It’s not a “fake idea”. It’s just someone’s idea. I hadn’t heard of it but I googled it upon reading this thread and it seems to be the idea that people tend to collectively remember things inaccurately in the exact same way. That phenomenon alone seems pretty plausible and not that dumb or fake, right?

But what isn’t plausible is the part you left out that’s talked about in the video? That some people explain the Mandela effect through pseudoscientific bullshit like alternative timelines merging. You also seem to conflate the ridiculousness of what some people collectively remember with the Mandela effect concept as a whole. It’s a bit like saying hypnosis as an idea is dumb because people do dumb things when hypnotised? I also don’t understand what is deeply offensive about people misremembering that Mandela died in prison? They’re not saying (or even remembering) that he was a bad person, probably the opposite, they’re just ignorant of history.

But having said all that I am perplexed by the OP comment: “I can’t help but think the Mandela effect is an example”. An example of what? Cracks in spacetime? Because yeah that’s dumb, though probably a joke.

>For someone that grew up in Apartheid South Africa I can't imagine how insulting this would be.

Maybe it's just too early, but why would it be offensive? Flabbergasting, sure, but offensive?

I imagine if someone told me they thought the sky was red my jaw would drop, but I wouldn't be angry.

Imagine a subset of people saying that there’s a phenomenon of people that believe MLK died in the 50’s of a heart attack.

People that seriously believe Mandela died in prison isn’t offensive, but I doubt these exist in any significant number. People claiming that it’s even possible that you could believe that is offensive since it implies his most effective years and actions never happened.

>People claiming that it’s even possible that you could believe that is offensive since it implies his most effective years and actions never happened.

I think that is reading into it too much. There are lots of other less offensive implications.

People are often unaware, uncritical, and misinformed. You can think this about a significant number of people while personally agreeing that Mendela had a large impact

Call it then Berenstain Effect then

I had heard about this effect (whatever you want to call it) a few years ago, but I remember things as the evidence shows they happened (ironically, with the exception of Mandela specifically, but I remember it differently than the group of others), so I had generally chalked it up to "when faulty memory meets Reddit."

Recently, though, I'm running into a weird one. In the last two months, I have encountered multiple incidents where people are either capitalizing "the Internet," or writing about why it's mainstream enough now that we don't need to capitalize "Internet."

In my timeline, no one, and I mean NO ONE, had been capitalizing "internet" for at least fifteen years, and it was only really old people who did for five. It looks ridiculous to me even to see it.

I can't account for this change by any normal means, and it's been really eerie!

That sounds more like Baader-Meinhoff. Which I just had to look up earlier this week for the first time in probably a decade. xD

(I’m one of those old heads that still capitalize it btw)

The I am your father, Luke - effect.

I can't speak for everyone, since my memory is different even from the consensus memory of other people who remember his dying in prison, but I can tell you what I "remember," and why it may not be as absurd as you think.

I misremember his dying in prison in 1993. In my false memory, he never became Prime Minister. His death inspired the movement that finally ended Apartheid, but he didn't do it himself. His death was interpreted as a kind of martyrdom for his cause, and as the deaths of martyrs often does, it evoked sympathy even in the hearts of people who disagreed with him, eventually leading to the end of Apartheid.

I was only 7 in 1993, so I'm more than willing to accept that I'm just misremembering completely. My geopolitical awareness in the 2nd grade was pitiful by the most generous interpretation. Perhaps I'm conflating lots of different pieces of other stories and mistakenly associating them with his name. My memory is generally quite reliable, in my experience, but it's a long way from foolproof. I do remember being genuinely surprised when he actually died, long before I heard of the "Mandela Effect," because I thought I could remember the lesson in 2nd grade when we learned of his death in prison.

I just wanted to mention it's a whole different set of memories, including his position and role in ending Apartheid, that I misremember, not just the circumstances of his death, and I would guess that's true of others as well.

At least in my mismemory, he was still heroic, and his life (and death) inspired the change he's remembered for now. I would hope not to insult anyone just because my memories of my ignorance as a small child don't match what actually happened.

I'm going to reply in support of your post. To add my voice to your chorus.

I really fucking hate the "Mandela effect". It's a symptom of a much greater problem: people refusing to be wrong.

Now when someone can be shown clear evidence that their memory is in error, they can claim that fucking reality itself has been changed. Apparently the only thing that is rock solid, 100% sure is our own memory. That is sacrosanct. Can't question it. Our own memory is a 100% accurate recording of everything we've ever experienced and cannot be influenced by anything ever.

Except for all of the evidence that shows us the exact opposite.

So how about we all be humble enough to say, "Ah, guess I was wrong" from time to time.

I grew up thinking he died in the late 90s, but that was just him retiring from politics.

"becoming prime minister"

He was President.

no that's just the mandela effect again /s

(but actually thanks for pointing that out, I corrected it)

Can you elaborate on that?

Because there was no big bang. The universe slowly goes to the "black side" through black holes, and when it's finished, it goes to the "white side" in a kind of big bang, but no so violent. And the cycle repeats.

This isn't likely since the geometry as we've attempted to model of the inside of a blackhole wouldn't be so flat. There's a PBS Spacetime episode covering this idea and they explain how it's not possible and if it was possible how it might be so. In any case, the answer is probably no.

[citation needed]

I think the OP meant Cyclic Universe theory by Penrose: https://m.youtube.com/watch?v=K_FUlo8BF9Y

Sounds more like an inspiration taken from Clarke's 2001, when Bowman travels through the Monolith to space Grand Central in inverted universe

In a thread about scientific questions so out-of-reach that we can barely put names to the yawning chasms in collective human understanding...

It might be unrealistic to expect any proffered answer to come with a reputable citation.

I'm sharing my own idea.

I think you rather badly misunderstand what physics is. It's not a field where you try to convince people of some kind of emotionally compelling origin story you just invented. It's a field where you measure a bunch of things, relate the numbers with some sort of equation, and (optionally!) describe the equation with some sort of layman-friendly metaphor, to build intuition. You can't skip straight to the metaphor! Where are your numbers? On what basis do you claim this radical departure from established physics? Why should we listen to you?

And I think you forgot we're just commenting an article on hacker news, not publishing to a physics journal :) By skipping to the metaphor I'm doing a small inception in your minds, you physicists out there. Now this idea will never leave you :)

I'm pretty sure most physicists are aware of the cyclic universe theory, it's just that there's very little evidence to support it.

And are we sure it doesn't predict cosmic strings just as much as the big bang model does? Both involve the universe being very hot and dense in the past and then getting rapidly cooler. That's the part that makes physicists expect cosmic strings, not the question of where the hot-dense state came from in the first place.

Although i completely agree with your point, one could also say that before equations and models, there's observation and intuition.

One could argue that metaphores are a step to move the science back toward reality and "complete the circle".

> emotionally compelling origin story you just invented

This doesn't seem to describe the previous comment. It's not just invented, and not emotionally compelling. It's just a fun idea.

> You can't skip straight to the metaphor! Where are your numbers?

I have a story about ants on a rubber sheet for you.

> Because there was no big bang.

Bingo. Whatever evidence is claimed to exist is only ever indirect. We cannot recreate the big bang, claiming it happened is worse than claiming it didn't happen.

I don't think your black hole points are correct but it's fun to consider.

"He who created seven heavens in layers. You see no discrepancy in the creation of the Compassionate. Look again. Can you see any cracks?" - Clear Qur'an

"[And] who created seven heavens in layers. You do not see in the creation of the Most Merciful any inconsistency. So return [your] vision [to the sky]; do you see any breaks?" - Sahih international translation

67:3 Qur'an

(I'm a moderator here.) I appreciate the comments you've posted, up to a point, but using HN primarily for religious comments is not allowed on HN. It's guaranteed to lead to religious flamewar, which we definitely don't want on HN. We want thoughtful, curious conversation on a variety of intellectually interesting topics.

Intellectual curiosity can certainly overlap with comments drawn from religious experience, knowledge of religious history and scholarship, etc. All that is great—from time to time. What's not ok are religion-driven polemics or using the site primarily for religious comments.

If you wouldn't mind reviewing https://news.ycombinator.com/newsguidelines.html and taking the intended spirit of the site more to heart, we'd be grateful.

Thank you for reply. Yep that make sense. I understand that mentioning religion may result in threads that are low effort (insults, fallacious arguments etc). I will make sure that if I were to comment regarding religion in the future, it would be in the framework of this site's guidelines promoting interesting discussion and perspectives.

I thought it was fun to see the same sort of metaphor used.

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