r/mathematics Aug 29 '21

Discussion Collatz (and other famous problems)

195 Upvotes

You may have noticed an uptick in posts related to the Collatz Conjecture lately, prompted by this excellent Veritasium video. To try to make these more manageable, we’re going to temporarily ask that all Collatz-related discussions happen here in this mega-thread. Feel free to post questions, thoughts, or your attempts at a proof (for longer proof attempts, a few sentences explaining the idea and a link to the full proof elsewhere may work better than trying to fit it all in the comments).

A note on proof attempts

Collatz is a deceptive problem. It is common for people working on it to have a proof that feels like it should work, but actually has a subtle, but serious, issue. Please note: Your proof, no matter how airtight it looks to you, probably has a hole in it somewhere. And that’s ok! Working on a tough problem like this can be a great way to get some experience in thinking rigorously about definitions, reasoning mathematically, explaining your ideas to others, and understanding what it means to “prove” something. Just know that if you go into this with an attitude of “Can someone help me see why this apparent proof doesn’t work?” rather than “I am confident that I have solved this incredibly difficult problem” you may get a better response from posters.

There is also a community, r/collatz, that is focused on this. I am not very familiar with it and can’t vouch for it, but if you are very interested in this conjecture, you might want to check it out.

Finally: Collatz proof attempts have definitely been the most plentiful lately, but we will also be asking those with proof attempts of other famous unsolved conjectures to confine themselves to this thread.

Thanks!


r/mathematics May 24 '21

Announcement State of the Sub - Announcements and Feedback

116 Upvotes

As you might have already noticed, we are pleased to announce that we have expanded the mod team and you can expect an increased mod presence in the sub. Please welcome u/mazzar, u/beeskness420 and u/Notya_Bisnes to the mod team.

We are grateful to all previous mods who have kept the sub alive all this time and happy to assist in taking care of the sub and other mod duties.

In view of these recent changes, we feel like it's high time for another meta community discussion.

What even is this sub?

A question that has been brought up quite a few times is: What's the point of this sub? (especially since r/math already exists)

Various propositions had been put forward as to what people expect in the sub. One thing almost everyone agrees on is that this is not a sub for homework type questions as several subs exist for that purpose already. This will always be the case and will be strictly enforced going forward.

Some had suggested to reserve r/mathematics solely for advanced math (at least undergrad level) and be more restrictive than r/math. At the other end of the spectrum others had suggested a laissez-faire approach of being open to any and everything.

Functionally however, almost organically, the sub has been something in between, less strict than r/math but not free-for-all either. At least for the time being, we don't plan on upsetting that status quo and we can continue being a slightly less strict and more inclusive version of r/math. We also have a new rule in place against low-quality content/crankery/bad-mathematics that will be enforced.

Self-Promotion rule

Another issue we want to discuss is the question of self-promotion. According to the current rule, if one were were to share a really nice math blog post/video etc someone else has written/created, that's allowed but if one were to share something good they had created themselves they wouldn't be allowed to share it, which we think is slightly unfair. If Grant Sanderson wanted to share one of his videos (not that he needs to), I think we can agree that should be allowed.

In that respect we propose a rule change to allow content-based (and only content-based) self-promotion on a designated day of the week (Saturday) and only allow good-quality/interesting content. Mod discretion will apply. We might even have a set quota of how many self-promotion posts to allow on a given Saturday so as not to flood the feed with such. Details will be ironed out as we go forward. Ads, affiliate marketing and all other forms of self-promotion are still a strict no-no and can get you banned.

Ideally, if you wanna share your own content, good practice would be to give an overview/ description of the content along with any link. Don't just drop a url and call it a day.

Use the report function

By design, all users play a crucial role in maintaining the quality of the sub by using the report function on posts/comments that violate the rules. We encourage you to do so, it helps us by bringing attention to items that need mod action.

Ban policy

As a rule, we try our best to avoid permanent bans unless we are forced to in egregious circumstances. This includes among other things repeated violations of Reddit's content policy, especially regarding spamming. In other cases, repeated rule violations will earn you warnings and in more extreme cases temporary bans of appropriate lengths. At every point we will give you ample opportunities to rectify your behavior. We don't wanna ban anyone unless it becomes absolutely necessary to do so. Bans can also be appealed against in mod-mail if you think you can be a productive member of the community going forward.

Feedback

Finally, we want to hear your feedback and suggestions regarding the points mentioned above and also other things you might have in mind. Please feel free to comment below. The modmail is also open for that purpose.


r/mathematics 5h ago

Dinitz-Garg-Goemans conjecture is false

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chatgpt.com
172 Upvotes

r/mathematics 47m ago

6 open erdos problems solved by GPT. 5.6 Sol

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Upvotes

So 6 open erdos problems were just solved. GitHub link shows both prompts used and solutions verified by lean. All used GPT 5.6 Sol.

The general way to structure prompts is also mentioned in the twitter thread!

Credits: https://x.com/qiaoqiao2001/status/2080003441821163958?s=46


r/mathematics 5h ago

Prime Indicator Function

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17 Upvotes

r/mathematics 4h ago

Digit Reversal Function

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7 Upvotes

r/mathematics 43m ago

what minor did you do as a math major

Upvotes

im sorry if this is the wrong place to ask but what minor did you choose if you did a math major?? Im honestly having such a hard time and thinking about just not doing a minor. (Maybe stats or Econ ????)


r/mathematics 4h ago

Any Applied Math/Statistics majors NOT go CS/finance/medicine route?

5 Upvotes

I'm planning my undergrad degree and would love to hear from people who studied Applied Mathematics and Statistics. I love using math to understand complex systems and am most interested in things like space, weather, oceans, history, culture, and languages. Since I obviously can't major in all of those, I'm considering majoring in Applied Mathematics and minoring in Statistics because it seems like a flexible foundation that could be applied to many different fields. Unfortunately whenever I search for career paths, I mostly find people who went into computer science/tech, finance, or medicine which is fine but I'm not interested in those fields at all. Has anyone here used an Applied Math/Stats background in scientific research or other interdisciplinary fields like the ones I'm interested in. If so, what's your profession? If you're in science, what field are you in? I'd like to know more about using applied math/stats in areas like atmospheric science, oceanography, astronomy, environmental science, archaeology, linguistics, history, geography, or the digital humanities. I'm trying to understand how broad the field really is and what kinds of careers people have actually built with this background. I'd love to hear about any less common paths that you've taken.


r/mathematics 20h ago

Discussion What's a Problem Solver to Do? (PhD Student Looking for Guidance)

82 Upvotes

I'm a PhD student working in probability and analysis, and right now the problem I'm working on could be considered a moderate extension of some existing theory. But it seems like AI is leading to the rapid devaluation of such work and pure "problem solving" as a skill in general (see for example https://davidbessis.substack.com/p/the-fall-of-the-theorem-economy ). If i were to summarize with an analogy - the stock of combinatorialists feels like it is falling while that of people working on geometric Langlands feels like it is rising.

The common sentiment pretty much everywhere seems to be that mathematicians will now be AI guiders and checkers (although the status quo is changing quite literally every day), and those with a wide vision of the entire mathematical "forest" will survive and those who "solve problems for the sake of solving problems" will not or at least will be deprioritized. Honestly, when I think about it, the problem I am working on is small enough in scope that it could probably just be plugged into ChatGPT Pro and solved after some thinking by the model, with no input of my own except a decent prompt. And I have a subscription to GPT Pro, but I still struggle to do that because it just feels so pointless. But at the same time, I feel pointless and obsolete, because - well I am, because my core skillset is problem solving.

Everywhere I look, I see posts stating something to the effect of "solving problems is not the point of mathematics, improving understanding is". And I kind of get it, it's a little evidenced by the counterexample to the Jacobian conjecture, which I saw, and basically said - ok cool, now what? But on the other end, as someone who enjoys struggling with a problem (without thinking about any broader implications), that aspect of math disappearing is deflating. As Paul Halmos famously said:

"Don't just read it; fight it! Ask your own questions, look for your own examples, discover your own proofs. Is the hypothesis necessary? Is the converse true? What happens in the classical special case? What about the degenerate cases? Where does the proof use the hypothesis?"

Sorry, this turned into a rant, but I assume many others are struggling with this transition and I wanted to just get a consensus and some opinions of what people are doing or think is the right thing to do, other than just quit and start feeding questions to AI and become AI guiders. Because if that's what math is going to become, I'd rather not do it and just pursue another field. Literally today, I found a paper on the Arxiv which literally set up a system to autonomously dig through arxiv papers for open problems and then feed them to some kind of LLM to see if it can prove it. Sure, this kind of activity is seeking truth and trying to advance the frontiers of mathematical knowledge - but is this really the point of math? Is this really what it's all about and what it's all going to be?

Here's an example of a non-specialist proving a result which is true just by plopping it into an LLM - it is literally "vibe math":

https://x.com/vikvang1/status/2079370200286433340

The example below is by people who are experts in the field, but basically created an autonomous system to trawl papers for open problems and then feed them into LLMs so that they can find solutions. Big caveat here: I have a lot of respect for the authors - they discuss the impacts of AI in terms of dislocation of early career researchers, and the general societal impacts and how humans are still important. I laud them for that. But still, it's ultimately an automated system to find problems and solve them, almost for the sake of solving them.

https://arxiv.org/html/2607.17388v1

What is the point of working on specialized/non-famous problems and understanding a field deeply if this is what's happening now?


r/mathematics 14m ago

Number Theory Why hasn't we tried using Lean to formally verify Mochizuki's ABC Conjecture proof?

Upvotes

I recently learned about Shinichi Mochizuki's claimed proof of the ABC Conjecture through his Inter-universal Teichmüller (IUT) theory. From what I understand, the proof spans around 500 pages and introduces a large amount of entirely new mathematics. The main reason it remains controversial is that several experts, most notably Peter Scholze and Jakob Stix, argued that there is a serious gap or flaw in a key part of the argument, while Mochizuki has disagreed with their assessment.

This made me wonder: why hasn't anyone tried to formalize the entire proof in a proof assistant like Lean?

In principle, if every definition, theorem, and logical step were encoded in Lean, wouldn't it be possible to determine whether the proof is logically valid? I realize formalizing 500+ pages of highly abstract mathematics would be an enormous undertaking—especially since much of IUT theory would likely need to be built from scratch—but would such a project be feasible in the long run?

Or is the difficulty not just the size of the proof, but that there are parts of the mathematics that are still too unclear or disputed to even formalize unambiguously?

I'd be interested to hear from people familiar with formal verification or IUT theory.


r/mathematics 26m ago

What to do with a bachelors in applied math?

Upvotes

Hello!

I am going to graduate in December with a degree in Applied Mathematics. I have had a variety of interests through my classes (cryptography, options, optimization, amongst a few others), but I am unsure as to do what I want to actually do once I graduate. I have started to consider graduate school, but I was wondering if I should rule that out since I’m already unsure on what to specialize in. Any advice/discussion is welcome, just trying to hear others thoughts and experiences.


r/mathematics 41m ago

Calculus Calculus 2

Upvotes

Hey all. I am studying calculus 2 this summer and my professor has put forward a new criteria for getting an A and a quite unrealistic one at that. He said if using chatgpt or any assistance , we are able to create a new convergence test that has never been presented before (works even if it is applicable for even just a few types of series and fails for others) , we can get a good grade. Is it kinda possible that we do this? Has anybody got an idea. HELPPPP

p.s dont mind my english, its my 2nd language.


r/mathematics 17h ago

Geometry Happy Real π Day!

14 Upvotes

For those that celebrate.


r/mathematics 1d ago

How much recognition/reward would a human researcher receive for the counterexample to the Jacobian Conjecture?

111 Upvotes

Hypothetically let's assume that a human math researcher had come up with the counterexample (along with a class of counterexamples similar to the one given by Claude) to the Jacobian Conjecture before the AI era. How much recognition would that person receive? Is this an automatic tenure at a top university? Does the person become a contender for the Fields Medal? Or is it just a good CV booster but no major impact on that person's career by itself.


r/mathematics 11h ago

Need suggestions for phd

2 Upvotes

My bro has qualified gate and net in maths both exam. Can anyone please tell me best institute/university for phd(maths) and complete procedure. And when university open their application forms for admission


r/mathematics 2h ago

Discussion Would there be any interest in a mathematician / programmer collab here?

0 Upvotes

I’m a programmer with an interest in math so I subscribe here. Seems AI is doing a lot of work in this field and I’m sure plenty of mathematicians are interested in leveraging AI. I and other devs have a lot of experience in how to do so. I was thinking that it might be beneficial to have a thread where we work together to try and optimize your setup so that you can utilize these tools more effectively.

This was motivated by a recent exchange in this subreddit where a mathematician was saying "I’ve never heard of subagents" and I realized that you guys might be able to accomplish a lot more if we put our heads together.


r/mathematics 17h ago

Calculus CLEP: OpenStax's Calc 1 book good enough?

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2 Upvotes

r/mathematics 1d ago

Discussion What's one math topic that completely changed how you think?

65 Upvotes

r/mathematics 1d ago

What even is the point of non-integer factorials?

10 Upvotes

The other day, I saw a YouTube video on 1.5! and the Gamma Function, and I understood like half of the maths behind it, but I couldn't really understand why extending the factorial to real numbers and complex numbers is so important. Could someone explain it so a high schooler could understand? Thank you.


r/mathematics 1d ago

AI and the future of formal math education

20 Upvotes

I'm a medical doctor in my 50's, a long time lurker here with a passion for math but no mathematical training. I have signed up for a Bachelors in Mathematics (Hons) to be done while continuing to practice medicine. The logistics of completing the course are not an issue. I am doing this purely for the joy of the subject, to have some formalization of learning and maybe then go on to do a Master's or more (i.e. this is not for career development/pivoting - at least not at this point!) What I would like thoughts on is where you see formal training/education going in the coming years. Will having a Master's or PhD in Math lose it's cachet or utility with AI being accessible to the lay public and becoming more adept at solving problems etc (a recent 'theme' here on this forum)? I do realize the study process, learning how to do proofs and think mathematically will be good for my intellectual development. Curious as to some expert perspectives.


r/mathematics 1d ago

Problem solving strategies

7 Upvotes

Has Anyone read this book Problem Solving Strategies by Arthur Engel? I am a 19 year old pursuing engineering. I love math and programming, I am trying to be better at it.


r/mathematics 2d ago

Jacobian conjecture down with a hand checkable counterexample, has been open since 1939

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1.6k Upvotes

r/mathematics 1d ago

Discussion Should I switch from Applied math to Applied statistics to increase my job opportunities?

5 Upvotes

Greetings.

as you can see in my post, I’m contemplating to switch from Applied math to Applied stat.

the curriculum in two years is the same, but later on specializes, for stat it gets into…well stats in general, while applied math learns more into computional science and modeling&simulation.

my thought is, if I switch would my job seeking would approve?

I choose applied math since I couldn’t get into tech department, and that I’m pretty good at both math and coding.

and the idea of working in a robotics field also makes me interested.


r/mathematics 1d ago

Nested Dodecahedrons Sequence, Ana Kiladze, Ink/Paper, 2025

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3 Upvotes

r/mathematics 1d ago

To the Mathematics students applying for PhD programsin USA: what has your experience been like when emailing professors?

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4 Upvotes