Repository of problems worth solving
World Solve is a public institutional repository for identifying real unresolved problems across science, society, health, governance, economics, and local systems. Each entry is intended to be citable, inspectable, and actionable.
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4194Total
4194Open
0Solved
9Humans
open
Global / Unspecified, Global
Classifying all finite simple groups was a monumental achievement, but fully understanding how all groups relate to and build from these simple pieces remains an ongoing task. This shapes our foundational understanding of symmetry itself.
mathematics-logic
global-unspecified
every
groups
finite
don
know
whether
group
understood
piece
some
philosophy-ethics
resolved
haven
possible
mathematical
open
Global / Unspecified, Global
While the standard cube's maximum was determined through massive computation, generalized versions with more dimensions or larger sizes remain computationally and theoretically unresolved. This connects group theory with combinatorial optimization.
mathematics-logic
global-unspecified
dimensions
don
know
exact
largest
number
moves
required
solve
any
whether
haven
resolved
possible
every
philosophy-ethics
open
Global / Unspecified, Global
Certain constructions, like doubling a cube's volume using classical tools, were proven impossible, but a full classification of every possible constructible versus non-constructible case remains an evolving area. This connects ancient geometry with modern algebra.
mathematics-logic
global-unspecified
don
know
whether
set
numbers
never
precisely
constructed
only
compass
haven
possible
resolved
philosophy-ethics
every
mathematical
open
Global / Unspecified, Global
Formulas exist for degrees up to four, but general algebraic solutions for higher degrees don't exist in the same closed form, leaving open questions about alternative methods. This shapes ongoing research in both pure and computational algebra.
technology-computing
global-unspecified
general
haven
determined
whether
there
exists
efficient
algorithm
solving
all
mathematics-logic
philosophy-ethics
know
possible
resolved
every
open
Global / Unspecified, Global
Some mathematical truths may be true but fundamentally unprovable within any given formal system, a possibility raised by Gödel's work but not fully mapped out for all classes of statements. This unresolved boundary shapes the philosophy of computation.
technology-computing
global-unspecified
true
given
don
know
whether
every
statement
whole
numbers
eventually
philosophy-ethics
haven
resolved
mathematics-logic
possible
open
Global / Unspecified, Global
Gödel's incompleteness theorem confirms this for many systems, but fully mapping which systems are exempt, if any, from this limitation remains an open and active question. This continues to shape foundational debates in mathematical logic.
mathematics-logic
global-unspecified
don
know
whether
every
sufficiently
complex
logical
system
must
eventually
philosophy-ethics
resolved
haven
systems
possible
open
Global / Unspecified, Global
Arrow's Impossibility Theorem proved certain fairness conditions can't all hold at once for common voting systems, but the full landscape of tradeoffs across all possible systems remains an active research area. This has real implications for the design of democratic institutions.
mathematics-logic
global-unspecified
possible
voting
fairness
don
know
whether
mathematically
create
completely
fair
systems
philosophy-ethics
resolved
haven
every
open
Global / Unspecified, Global
Despite extensive computation, no proof confirms whether these digits behave truly randomly forever or eventually reveal some hidden structure. This remains an open question bridging number theory and statistics.
mathematics-logic
global-unspecified
whether
digits
number
don
know
well-known
mathematical
constants
like
euler
haven
philosophy-ethics
resolved
possible
every
open
Global / Unspecified, Global
Some modern proofs rely heavily on computer verification because they're too long or complex for any person to check by hand, raising open questions about whether shorter, purely human-verifiable proofs must always exist. This unresolved tension touches both mathematics and epistemology.
mathematics-logic
global-unspecified
whether
computer
don
know
every
mathematical
proof
principle
shortened
version
philosophy-ethics
haven
resolved
possible
open
Global / Unspecified, Global
This is the famous Halting Problem, proven impossible to solve in full generality, yet many partial and practical questions around predicting program behavior remain actively studied. This shapes the theoretical limits of what computers can ever determine about themselves.
technology-computing
global-unspecified
program
whether
determine
don
know
possible
build
computer
always
any
haven
resolved
philosophy-ethics
mathematics-logic
every
open
Global / Unspecified, Global
Some tiling patterns work perfectly in abstract mathematical space but haven't been proven physically constructible under all real-world constraints. This connects pure geometry with material and structural engineering.
mathematics-logic
global-unspecified
tiling
physically
don
know
whether
every
regular
geometric
pattern
appears
haven
resolved
possible
philosophy-ethics
mathematical
open
Global / Unspecified, Global
Ramsey-type problems ask whether order must always emerge within sufficiently large or complex systems, and while some cases are proven, the general boundaries remain incompletely mapped. This connects deeply to combinatorics and the philosophy of mathematical order.
mathematics-logic
global-unspecified
structure
whether
mathematical
must
always
don
know
every
finite
certain
haven
resolved
philosophy-ethics
possible
open
Global / Unspecified, Global
Some lower bounds on computational efficiency are proven for specific tasks, but a fully unified theory covering every possible algorithmic problem remains unresolved. This unresolved question shapes the outer limits of computer science.
technology-computing
global-unspecified
don
know
whether
there
maximum
theoretical
limit
efficiently
any
sorting
philosophy-ethics
resolved
haven
mathematics-logic
possible
every
open
Global / Unspecified, Global
Game theory has solved many two-player scenarios completely, but multiplayer games with shifting alliances and incomplete information remain far less understood in full generality. This unresolved question has real implications for economics and political strategy.
economics-resources
global-unspecified
strategy
multiplayer
games
don
know
whether
every
possible
complex
reduced
philosophy-ethics
resolved
haven
mathematics-logic
mathematical
open
Global / Unspecified, Global
This long-standing conjecture claims there's always at least one prime number between any two consecutive perfect squares, and while verified extensively by computer, no general proof exists. Solving it would sharpen our understanding of prime distribution.
mathematics-logic
global-unspecified
there
conjecture
always
between
consecutive
perfect
squares
don
know
whether
haven
possible
every
philosophy-ethics
resolved
mathematical
open
Global / Unspecified, Global
Various conjectures link the number of prime factors a number has to specific patterns of behavior, but many of these connections remain only partially proven. This continues to be explored within analytic number theory.
mathematics-logic
global-unspecified
number
prime
factors
has
don
know
whether
exact
minimum
distinct
haven
possible
every
resolved
philosophy-ethics
mathematical
open
Global / Unspecified, Global
Modern cryptography largely depends on problems assumed, but not proven, to be computationally hard, leaving a theoretical gap in fully guaranteed security. This unresolved foundation underlies much of digital security today.
mathematics-logic
global-unspecified
don
know
whether
possible
construct
truly
unbreakable
code
only
mathematical
philosophy-ethics
resolved
haven
every
open
Global / Unspecified, Global
Fair division theory has strong results for two-party negotiations, but multi-party fairness guarantees become significantly harder to prove in full generality. This unresolved area connects mathematics with real-world conflict resolution.
mathematics-logic
global-unspecified
fair
don
know
whether
mathematically
possible
guarantee
perfectly
outcome
any
philosophy-ethics
haven
resolved
every
open
Global / Unspecified, Global
Some deterministic functions produce output so irregular it resembles randomness, and a complete classification of exactly which rules produce this behavior remains incomplete. This unresolved boundary connects number theory, chaos theory, and computer science.
mathematics-logic
global-unspecified
deterministic
don
know
whether
possible
fully
characterize
every
mathematical
function
haven
philosophy-ethics
resolved
open
Global / Unspecified, Global
Certain recursively defined sequences appear statistically random for enormous stretches, yet whether hidden structure always eventually emerges remains an open and evolving question. This connects deeply to both number theory and the study of pseudorandomness.
mathematics-logic
global-unspecified
whether
always
eventually
don
know
digits
numbers
produced
simple
recursive
haven
philosophy-ethics
resolved
possible
every
mathematical