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
Despite chess being fully deterministic with no hidden information, its complexity is so vast that no one has proven who truly holds the advantage under perfect play. Solving smaller games has offered clues, but full chess remains unresolved.
mathematics-logic
global-unspecified
chess
has
proven
haven
whether
principle
always
guaranteed
winning
drawing
philosophy-ethics
resolved
possible
know
every
mathematical
open
Global / Unspecified, Global
Mathematicians have many tools for distinguishing knots, but no single method works perfectly and efficiently for every possible case. This unsolved problem sits at the heart of the mathematical field of knot theory.
mathematics-logic
global-unspecified
every
knot
don
know
whether
told
apart
simple
efficient
resolved
philosophy-ethics
haven
possible
mathematical
open
Global / Unspecified, Global
Starting from any positive number and repeatedly applying a basic rule always seems to eventually reach the number one, but no proof confirms this holds for every possible starting point. Its simplicity contrasted with its difficulty has made it famous among mathematicians and hobbyists alike.
mathematics-logic
global-unspecified
rule
seems
always
haven
proven
collatz
conjecture
strikingly
simple
lead
whether
know
possible
every
mathematical
resolved
open
Global / Unspecified, Global
This question, closely related to the once-open Poincaré Conjecture, has been resolved in three dimensions but opens further mysteries in higher-dimensional analogues. Exploring these generalizations remains an active area of topology.
mathematics-logic
global-unspecified
don
know
whether
every
simply
connected
three-dimensional
shape
holes
always
haven
resolved
philosophy-ethics
possible
open
Global / Unspecified, Global
The famous four-color theorem was resolved for flat maps, but generalizing the problem to more complex or higher-dimensional surfaces remains unsettled in several cases. This continues to be explored in graph theory and topology.
mathematics-logic
global-unspecified
color
flat
haven
determined
exact
minimum
number
colors
needed
any
whether
philosophy-ethics
know
resolved
possible
every
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
Quantum computers show promise for specific problems like factoring, but whether they offer a genuine speedup across all hard computational problems remains unproven. This question sits at the intersection of mathematics, physics, and computer science.
mathematics-logic
global-unspecified
computers
whether
quantum
haven
resolved
efficiently
solve
every
currently
considered
know
philosophy-ethics
possible
mathematical
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
Some games are proven to always end in a draw or a specific winner under perfect play, but for many complex games, this remains unresolved due to sheer computational scale. This unsolved area touches game theory, logic, and computer science.
mathematics-logic
global-unspecified
proven
game
draw
haven
whether
every
possible
strategy
complete
information
resolved
philosophy-ethics
know
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
Sorting algorithms have been optimized extensively, but proving a true absolute lower bound across all possible sorting methods remains an unresolved question in computational theory. This affects the fundamental efficiency limits of computing.
technology-computing
global-unspecified
limits
haven
resolved
whether
number
steps
needed
sort
any
list
philosophy-ethics
know
mathematics-logic
possible
every
mathematical
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
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
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
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
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
Graph theory offers many partial answers about guaranteed patterns within large networks, but a fully general and complete theory covering every possible network structure remains incomplete. This affects our understanding of everything from social networks to biological systems.
mathematics-logic
global-unspecified
every
network
haven
determined
whether
sufficiently
complex
connections
must
always
possible
philosophy-ethics
resolved
know
mathematical