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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4094Total
4094Open
0Solved
9Humans
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
Physical laws impose some theoretical limits on computation speed and energy use, but the exact universal boundary, if one truly exists, remains unresolved. This connects computer science directly to fundamental physics.
technology-computing
global-unspecified
physical
computer
haven
proven
whether
there
maximum
limit
efficiently
any
philosophy-ethics
mathematics-logic
resolved
know
possible
every
open
Global / Unspecified, Global
Irrational numbers have infinite, non-repeating digits, and while we can calculate them to enormous precision, no simple predictive pattern for their exact sequence has been found. This touches on deep unresolved questions in number theory.
mathematics-logic
global-unspecified
pattern
digits
irrational
numbers
haven
determined
whether
possible
find
predicting
know
resolved
philosophy-ethics
every
mathematical
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
The Continuum Hypothesis asks whether there's a size of infinity strictly between the countable and uncountable, and it has been shown to be independent of standard mathematical axioms. This unresolved question touches the very foundation of set theory.
mathematics-logic
global-unspecified
whether
set
size
mathematical
haven
resolved
every
infinite
numbers
must
know
philosophy-ethics
possible
open
Global / Unspecified, Global
Fair division problems become extremely complex once individual preferences differ, and general efficient solutions for many people remain incompletely understood. This connects mathematics to real-world negotiation and resource allocation.
mathematics-logic
global-unspecified
number
people
preferences
haven
proven
whether
always
possible
divide
cake
know
resolved
philosophy-ethics
every
mathematical
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
This problem, part of a broader family of questions in combinatorial geometry, has known bounds but no exact general formula for every configuration. Solving it would refine our understanding of how simple geometric constraints shape complex arrangements.
mathematics-logic
global-unspecified
exact
haven
determined
smallest
number
unit
distances
must
repeat
among
whether
know
possible
every
resolved
philosophy-ethics
open
Global / Unspecified, Global
Knot theory offers tools for identifying and classifying tangles, but calculating a guaranteed minimal ontangling path for every possible knot remains computationally unresolved. This connects abstract mathematics to physical intuition about rope and cords.
mathematics-logic
global-unspecified
every
possible
rope
minimal
haven
resolved
whether
tangle
idealized
mathematically
know
philosophy-ethics
mathematical
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
Palindromic and reversible primes show interesting patterns, but whether infinitely many exist across all number bases remains unconfirmed. This is one of many number-theoretic curiosities still lacking rigorous proof.
mathematics-logic
global-unspecified
prime
whether
infinitely
haven
proven
there
numbers
remain
you
reverse
know
possible
philosophy-ethics
resolved
every
mathematical
open
Global / Unspecified, Global
While specific puzzle sizes have been fully solved computationally, generalizing the worst-case difficulty formula across all puzzle sizes remains an open combinatorial question. This links recreational mathematics with formal complexity theory.
mathematics-logic
global-unspecified
haven
resolved
exact
minimum
number
moves
required
solve
hardest
possible
whether
know
philosophy-ethics
every
mathematical
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
Related conjectures about how primes combine remain only partially proven for specific ranges, without a fully general confirmed pattern. This connects to broader unresolved questions about the additive structure of prime numbers.
mathematics-logic
global-unspecified
prime
proven
numbers
haven
whether
every
sufficiently
large
number
written
know
possible
philosophy-ethics
resolved
mathematical
open
Global / Unspecified, Global
Finding the shortest possible route through many locations becomes exponentially harder as the number of locations grows, and no efficient exact solution is known for all cases. This unresolved question sits at the heart of computational optimization theory.
mathematics-logic
global-unspecified
efficient
haven
determined
whether
there
way
solve
every
instance
traveling
know
possible
philosophy-ethics
resolved
mathematical
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
Chaotic systems are famously sensitive to initial conditions, and whether their long-term patterns can ever be fully captured by simpler predictive rules remains an unresolved question in dynamical systems theory. This has real implications for weather prediction and other complex natural systems.
mathematics-logic
global-unspecified
whether
long-term
chaotic
rules
systems
haven
resolved
possible
always
predict
philosophy-ethics
know
society-governance
open
Global / Unspecified, Global
Partition numbers grow in a complex, only partially understood way, and while excellent approximations exist, a complete exact predictive formula for all cases remains elusive. This continues to be an active area within combinatorics and number theory.
mathematics-logic
global-unspecified
number
partition
numbers
understood
haven
proven
whether
distinct
ways
any
know
possible
philosophy-ethics
resolved
every
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
Even our best physical models rely on approximations or idealized assumptions, and whether a truly complete and exact mathematical simulation is even theoretically possible remains unresolved. This touches on the deep relationship between mathematics and the physical world.
mathematics-logic
global-unspecified
any
physical
whether
possible
exact
mathematical
haven
resolved
fully
simulate
philosophy-ethics
know
every