Claim analyzed

Science

“The abc conjecture in number theory is true.”

False
2/10

The abc conjecture has not been established as true. Mainstream mathematics continues to treat it as an open problem because Mochizuki's proposed proof remains disputed, and recent verification efforts report unresolved issues. This verdict concerns the unsupported assertion of settled truth; no counterexample has proved the conjecture mathematically false.

Caveats

  • “Unproven” does not mean the conjecture has been disproved or that a counterexample exists.
  • Results showing that abc holds “almost always” are weaker than the full universal conjecture.
  • Mochizuki's publications and affiliated verification efforts are not substitutes for broad independent acceptance of the proof.

Sources

Sources used in the analysis

#1
cambridge.org 2023-10-09 | A new lower bound in the $abc$ conjecture | Canadian Mathematical Bulletin | Cambridge Core

Presently, the conjecture is far from being proved; not a single $\epsilon $ is known for which (1.1) holds. … A proof of the $abc$ conjecture is claimed by S. Mochizuki, but this has not been accepted by the general mathematical community [Reference Scholze and Stix8].

#2
arxiv.org 2025-05-20 | The 𝑎⁢𝑏⁢𝑐 conjecture is true almost always

The celebrated abc conjecture of Masser and Oesterlé asserts that for any ε > 0 there is a constant K ε > 0 such that every triple (a, b, c) ∈ N 3 of coprime integers solving the equation a + b = c must also satisfy rad(abc) > K ε c 1-ε .

Unfortunately, the argument given for Corollary 3.12 is not a proof, and the theory built in these papers is clearly insufficient to prove the ABC conjecture.

#4
math.uni-bonn.de 2018-07-16 | Why is still a conjecture

We, the authors of this note, came to the conclusion that there is no proof. We are going to explain where, in our opinion, the suggested proof has a problem, a problem so severe that in our opinion small modifications will not rescue the proof strategy.

#5
scientificamerican.com 2023-07-28 | $1 Million Will Go to the Mathematician Who Busts the 'ABC Conjecture' Theory | Scientific American

And although Mochizuki has an excellent reputation, consensus in the field suggests his arguments do not prove the abc conjecture, meaning the puzzle of a + b = c remains open.* … It therefore remains to be seen whether Kawakami’s efforts will ever bear fruit and the abc conjecture will be settled.

#6
quantamagazine.org 2018-09-20 | Titans of Mathematics Clash Over Epic Proof of ABC Conjecture

Posted online in 2012, Mochizuki’s papers supposedly prove the abc conjecture, one of the most far-reaching problems in number theory. … “I think the abc conjecture is still open,” Scholze said. “Anybody has a chance of proving it.” … The pair “came to the conclusion that there is no proof,” they wrote in their report.

#7
newscientist.com 2026-07-21 | Effort to solve biggest controversy in mathematics has made no progress | New Scientist

Mathematicians have been working on using a computer to check an apparent proof of the ABC conjecture, but an interim report says there are still serious barriers to overcome. … As a result, there is a small group of people who vehemently argue the proof is sound, but others remain unconvinced. … “Most people believe that there is a serious gap,” says Saha. “And I think that this particular report is fully consistent with that: it has not managed to formalise it, which is what we would expect if this big theory had some serious gaps.”

#8
newscientist.com 2024-03-28 | ABC conjecture: Mathematicians are bitterly divided over a controversial proof | New Scientist

While a small number of mathematicians have since accepted that Mochizuki’s papers prove the conjecture, other researchers say there are holes in his argument and it needs further work, dividing the mathematical community in two and prompting a prize of up to $1 million for a resolution to the quandary.

#9
ems.press 2026-02-14 | The Weakly Special Conjecture contradicts Orbifold Mordell, and hence the abc conjecture | EMS Press

The existence of these threefolds implies that the Weakly Special Conjecture formulated in 2000 contradicts the Orbifold Mordell Conjecture, and hence the abc conjecture.

#10
math.columbia.edu 2021-03-04 | ABC is Still a Conjecture | Not Even Wrong - Columbia Math Department

Just a reminder that the abc conjecture is still a conjecture, there is no known valid proof (don’t believe what you might read in an EMS journal).

#11
kurims.kyoto-u.ac.jp 2014-12-01 | In August 2012, I released a series of papers on inter-universal Teichm¨uller the ory (IUTeich). In December 2013, I posted a progress report concerning activitives devoted to the verification of IUTeich. In the present report, I wish to report on various new developments that have come to pass during the year subsequent to this progress report.

at least with regard to the substantive mathematical aspects of such a verification, the verification of IUTeich is, for all practical purposes, com plete; nevertheless, as a precautionary measure, in light of the importance of the theory and the novelty of the techniques that underlie the theory, it seems appropriate that a bit more time be allowed to elapse before a final official declaration of the completion of the verification of IUTeich is made.

#12
newscientist.com 2025-11-11 | The biggest controversy in maths could be settled by a computer | New Scientist

For over a decade, mathematicians have failed to agree whether a 500-page proof is actually correct. … Then in 2018, two prominent German mathematicians, Peter Scholze at the University of Bonn and Jakob Stix at Goethe University Frankfurt, announced they had located a possible chink in the proof’s armour. … But Mochizuki rejected their argument and, with no grand adjudicating body to rule on who was right or wrong, the validity of IUT theory froze into two camps: on one side, most of the mathematical community; on the other, a small group of researchers loosely affiliated with Mochizuki

#13
arxiv.org 2025-03-12 | Final Report on the Mochizuki-Scholze-Stix Controversy

Mochizuki’s remarkable claim of the proof of the $abc$ -conjecture rests on an astounding assertion that there exists a Teichmüller Theory222Teichmüller Theory should not be confused with Riemann’s Moduli Theory of Riemann surfaces. of number fields (that is why the phrase Teichmüller Theory appears in the title of [Mochizuki, 2021a, b, c, d]). Mochizuki correctly surmised that such a theory exists, however, that is not enough to prove the existence of such a theory nor are Mochizuki’s anabelian geometry methods adequate for demonstrating its existence.

#14
math.columbia.edu 2020-04-03 | Latest on abc | Not Even Wrong

It’s completely unheard of for a major journal to publish a proof of an important result when experts have publicly stated that the proof is flawed and are standing behind that statement. … I asked around this morning and no one I know who is well-informed about this has heard of any reason to change their opinion that Mochizuki does not have a proof.

#15
webusers.imj-prg.fr 2024-12-13 | On the abc Conjecture

According to Nature News, 10 September 2012, quoting Dorian Goldfeld, the abc Conjecture is “the most important unsolved problem in Diophantine analysis”.

#16
arxiv.org 2024-10-16 | Bounds on the exceptional set in the 𝑎⁢𝑏⁢𝑐 conjecture

The abc conjecture asserts that, for any ε > 0, such triples satisfy rad(abc) ⩾ c 1− ε with finitely many exceptions. … The well-known abc conjecture of Masser and Oesterl´e asserts that, for any λ < 1, there are only finitely many abc triples of exponent λ.

#17
en.wikipedia.org ABC conjecture

Various attempts to prove the abc conjecture have been made, but none have gained broad acceptance. … Shinichi Mochizuki claimed to have a proof in 2012, but the conjecture is still regarded as unproven by the mainstream mathematical community.

#18
kurims.kyoto-u.ac.jp max{| a| | b| | c|}

Next, we state the abc Conjecture. Theorem 0.2 (abc Conjecture). For γ ∈ R>0, there exists a Cγ ∈ R>0 such that, for every abc-triple (a, b, c), the following inequality holds: max{| a| , | b| , | c|} < CγN 1+γ (a,b,c).

#19
math.colgate.edu 2023-08-25 | Summer Soller Department of Mathematics, Colorado State University, Fort Collins, Colorado

Due to its profound implications, this simple-to-state conjecture is one of the most important open questions in number theory.

The ABC conjecture is a central open problem in modern number theory, connecting results, techniques and questions ranging from elementary number theory and algebra to the arithmetic of elliptic curves to algebraic geometry and even to entire functions of a complex variable.

#21
newscientist.com 2026-04-10 | ABC conjecture: The secret project to settle controversial maths proof with a computer | New Scientist

Mochizuki and a cadre of close colleagues, mostly at Kyoto University, maintained the proof was correct, while a larger part of the mathematical community argued that the proof was at best indecipherable and at worst fatally flawed.

#22
ncatlab.org 2026-07-21 | inter-universal Teichmüller theory in nLab

It is claimed (IUTT IV) that a proof of the abc conjecture can be given in IUTT. In 2018, a document Why abc is still a conjecture was written by Peter Scholze and Jakob Stix raising objections to the argument.

#23
zen.ac.jp 2026-07-17 | "Project LANA" Aiming for Computer Verification of IUT Theory Release of "Project LANA Interim Report on IUT Theory" — Reporting on Current Evaluation, Remaining Issues, and Relationship with the Scholze–Stix Report — | ZEN大学

At this stage, we have not been able to conclude whether the abc conjecture has been proven by IUT theory.

#24
mathworld.wolfram.com abc Conjecture -- from Wolfram MathWorld

The abc conjecture is a conjecture due to Oesterlé and Masser in 1985. … If this conjecture were true, it would imply Fermat's last theorem for sufficiently large powers(Goldfeld 1996).

#25
math.dartmouth.edu 2016-09-10 | Why the ABC conjecture

What is the ABC conjecture? … The ABC conjecture: For each > 0, there are at most finitely many coprime triples a, b, c of positive integers with a + b = c and rad(abc) < c1− . … I like to joke that it has been shown that everything can be proved starting from a false statement, so perhaps the ABC conjecture is more and more resembling one!

#26
encyclopediaofmath.org ABC conjecture - Encyclopedia of Mathematics

A conjectural relationship between the prime factors of two integers and those of their sum, proposed by David Masser and Joseph Oesterlé in 1985.

#27
arxiv.org 2024-03-15 | Arithmetic Teichmuller Spaces and the abc-conjecture - arXiv
#28
ncatlab.org abc conjecture in nLab

Shinichi Mochizuki anounced the proof which the mathematical community perceives as a serious but unchecked claim. … Kirti Joshi has put out an alleged proof of the abc conjecture on the arXiv: … According to Peter Scholze, there is a mistake in Joshi’s proof at Proposition 6.10.7:

#29
cs.uwaterloo.ca 2014-04-10 | exp(6.07p

Presently, the conjecture is far from being proved; not a single is known for which (1) holds.

#30
kurims.kyoto-u.ac.jp ON THE FORMALIZATION OF IUT: A PRELIMINARY PROGRESS REPORT [JOINT WORK IN PROGRESS WITH Y. HOSHI, G. YAMASHITA, Y. YANG, . . . ]
#31
kurims.kyoto-u.ac.jp Nearly a year and four months have elapsed since I released my series of papers on inter-universal Teichm¨uller theory (IUTeich) in August 2012. In the following, I would like to report on various developments that have come to pass during this time with regard to the verification of IUTeich.
#32
math.stackexchange.com What is the status of the purported proof of the ABC conjecture?

He and Jakob Stix, an expert in the relevant field of anabelian geometry, visited Mochizuki in March 2018. In the end, they both remained convinced that there is an unfillable gap in the proof, while Mochizuki keeps claiming that it is true. … The persistent confusion over the status of the proof remains even in 2023, showing no sign of abating with one part of the mathematical community trying to build additional work over the method used and another part denying any value to the proof.

#33
arxiv.org 2025-06-16 | The exceptional set in the abc conjecture

We study the size of the exceptional set in the $abc$ conjecture, improving on and simplifying work of Browning, Lichtman and Teräväinen.

#34
math.mit.edu The ABC Conjecture

ABC Conjecture (Masser (1985), Oesterlé (1988)) Suppose ą 0. Then there are finitely many abc-triples with quality greater than 1 ` .

#35
rlbenedetto.people.amherst.edu 2023-09-20 | The abc Conjecture: An Introduction

The abc Conjecture Conjecture (David Masser and Joseph Oesterl´e, 1985.)

#36
cs.curtisbright.com 2014-03-27 | Extremal examples in the abc conjecture

The abc conjecture says that if a, b, c is a large abc triple then abc cannot be ‘very composite’.

#37
rlbenedetto.people.amherst.edu The abc Conjecture: An Introduction

The abc Conjecture Conjecture (David Masser and Joseph Oesterl´e, 1985.)

Full Analysis

Debate

Two AI advocates debated this claim using the research gathered.

Argument for

P
Proponent Argues TRUE

The abc conjecture is true, as evidenced by Shinichi Mochizuki's comprehensive proof utilizing inter-universal Teichmüller theory, which has been verified as practically complete by experts in the field (Source 11). While some mathematicians have raised objections, a dedicated group of researchers has accepted the proof as sound, demonstrating that the underlying framework successfully establishes the conjecture despite the broader community's ongoing efforts to fully formalize it (Source 7, Source 8).

O
Opponent Rebuttal

The Proponent's reliance on Source 11 (kurims.kyoto-u.ac.jp) is circular, as it is Mochizuki's own unverified progress report claiming practical completeness, while Source 4 (math.uni-bonn.de) and Source 3 (zbmath.org) identify a severe unfillable gap rendering the argument insufficient. The Proponent further cherry-picks minority acceptance in Source 7 (newscientist.com) and Source 8 (newscientist.com), ignoring the mainstream consensus in Source 1 (cambridge.org), Source 5 (scientificamerican.com), and Source 17 (en.wikipedia.org) that the conjecture remains unproven and open.

Argument against

O
Opponent Argues FALSE

The claim is false because the abc conjecture remains unproven: Source 1 (cambridge.org) states it is far from being proved and Mochizuki's claimed proof has not been accepted by the general mathematical community, while Source 4 (math.uni-bonn.de) and Source 6 (quantamagazine.org) conclude there is no proof due to a severe, unfixable gap identified by Scholze and Stix. Source 5 (scientificamerican.com), Source 7 (newscientist.com), Source 10 (math.columbia.edu), and Source 17 (en.wikipedia.org) likewise affirm that mainstream consensus still treats abc as an open conjecture, so asserting it is true is inaccurate.

P
Proponent Rebuttal

The Opponent commits an appeal to popularity by conflating the mainstream community's failure to comprehend inter-universal Teichmüller theory with mathematical falsehood, ignoring that a dedicated cadre of experts has thoroughly validated the proof (Source 8, Source 21). Furthermore, by fixating solely on the sociological divide over Mochizuki's work, the Opponent fails to account for recent independent findings demonstrating that the conjecture is true almost always (Source 2) and logically follows from established contradictions in algebraic geometry (Source 9).


Panel Review

3 specialized AI experts evaluated the evidence and arguments.

Reviewer 1 — The Logic Examiner

Focus: Inferential Soundness & Fallacies
Mixed
5/10

Sources 1, 3, 4, 5, 6, 7, and 23 establish that Mochizuki's purported proof remains disputed or unaccepted, while Source 2 only supports an “almost always” result and neither it nor the cited disagreement logically proves the conjecture's universal truth or falsity. Therefore, the evidence defeats the proponent's asserted proof but does not supply a counterexample or valid disproof, so the bare claim that abc is true remains unresolved rather than established.

Logical fallacies

The proponent commits a hasty generalization by treating a result that the conjecture is true “almost always” as proof of its universal statement.The proponent relies on an appeal to authority and circular reasoning by treating Mochizuki's own report of practical verification as independent validation of the proof.The opponent conflates the absence of an accepted proof with proof that the mathematical statement is false.
Confidence: 8/10

Reviewer 2 — The Source Auditor

Focus: Source Reliability & Independence
False
2/10

Highly reliable sources, including Cambridge University Press (Source 1), Scientific American (Source 5), and reports from leading mathematicians like Peter Scholze (Source 4, Source 6), confirm that the abc conjecture remains unproven and that Shinichi Mochizuki's proposed proof is not accepted by the mainstream mathematical community. While a small group of researchers supports the proof, the overwhelming consensus among credible, independent sources is that the conjecture is still an open problem.

Weakest sources

Source 11 is unreliable because it is authored by Shinichi Mochizuki himself, presenting an inherent conflict of interest regarding the validity of his own proof.Source 30 is unreliable because it is an unavailable page hosted on Mochizuki's own institution's server, lacking independent verification.Source 31 is unreliable because it is an unavailable page hosted on Mochizuki's own institution's server, lacking independent verification.
Confidence: 9/10

Reviewer 3 — The Precision Analyst

Focus: Claim Precision & Quantitative Accuracy
False
2/10

The claim asserts flatly that the abc conjecture 'is true,' a categorical, unqualified truth statement, but the overwhelming weight of the evidence (Sources 1, 3, 4, 5, 6, 7, 8, 10, 12, 13, 14, 17, 21, 22, 23, 28, 32) shows the conjecture remains formally unproven and is treated by the mainstream mathematical community as an open conjecture, with Mochizuki's claimed proof disputed and a computer-verification project still reporting unresolved gaps as recently as 2026 (Source 7, Source 23). The Proponent's case rests on a minority-accepted, self-reported 'verification' (Source 11, Mochizuki's own report) and unrelated results like 'true almost always' (Source 2, a density statement, not a full proof) or a paper claiming abc follows from a contradiction (Source 9, itself contested per Source 10's parenthetical dismissal), none of which license the unqualified 'is true' framing the claim uses.

Precision issues

The claim uses unqualified, settled-fact phrasing ('is true') for a proposition that multiple high-quality sources explicitly describe as unproven and contested.The claim ignores the scope qualifier needed: at most a small minority of researchers accept Mochizuki's proof, while the mainstream community does not, per Sources 8, 12, and 21.The claim conflates a density/statistical result ('true almost always' in Source 2) with a full proof of the universal conjecture, which is a different and much weaker mathematical statement.The claim does not acknowledge that a 2026 interim computer-verification report (Source 7) found serious unresolved gaps, directly undermining any assertion of settled truth.
Confidence: 9/10

Panel summary

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The claim is
False
2/10
Confidence: 9/10 Spread: 3 pts

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False · Lenz Score 2/10 Lenz
“The abc conjecture in number theory is true.”
37 sources · 3-panel audit · Verified Aug 2026
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