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
This mismatch is part of the evidence for dark matter, but the details of how it shapes galaxy rotation are still not fully worked out. A better model would sharpen our understanding of galaxy formation.
philosophy-ethics
global-unspecified
matter
haven
explained
some
galaxies
rotate
ways
don
match
visible
whether
know
mathematics-logic
resolved
determine
fully
open
Global / Unspecified, Global
Earth's magnetic field protects us from solar radiation, but the dynamo process that generates it deep underground is still only partly understood. This matters for predicting how long that protection will last.
climate-environment
global-unspecified
magnetic
earth
don
fully
understand
fields
form
behave
inside
planets
whether
philosophy-ethics
science-space
know
mathematics-logic
haven
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
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
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
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
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
open
Global / Unspecified, Global
Combinatorial geometry problems like this remain partially solved for specific shapes and configurations, but a fully general guarantee across all possible line arrangements is still unproven. This connects visual intuition with rigorous mathematical guarantees.
mathematics-logic
global-unspecified
like
specific
haven
resolved
whether
every
finite
set
straight
lines
know
possible
philosophy-ethics
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
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
Reconstruction problems in geometry ask how much partial information is truly enough to rebuild a full shape with certainty, and general limits for all shape classes remain incompletely understood. This connects pure mathematics to practical fields like imaging and tomography.
mathematics-logic
global-unspecified
shape
haven
determined
whether
every
finite
geometric
always
perfectly
reconstructed
know
resolved
possible
philosophy-ethics
mathematical
open
Global / Unspecified, Global
Combinatorial arrangement problems like this remain surprisingly resistant to full general solutions despite their simple appearance. This connects recreational mathematics with deeper unresolved questions in combinatorics.
mathematics-logic
global-unspecified
every
haven
proven
whether
finite
list
numbers
always
rearranged
sequence
know
possible
resolved
philosophy-ethics
mathematical
open
Global / Unspecified, Global
Self-referential systems often run into paradoxes, and while specific fixes exist for particular cases, no fully general and complete solution has been proven for every possible self-describing system. This unresolved tension remains central to mathematical logic and computer science.
mathematics-logic
global-unspecified
every
mathematical
fully
haven
determined
whether
sufficiently
complex
language
unambiguously
philosophy-ethics
resolved
possible
know
open
Global / Unspecified, Global
Many social systems implicitly reward productivity with greater respect or resources, yet most ethical traditions insist human worth shouldn't depend on usefulness alone. This unresolved tension underlies debates about disability, aging, and social value.
philosophy-ethics
global-unspecified
worth
productivity
don
have
resolved
way
determine
whether
fair
base
know
haven
open
Global / Unspecified, Global
Competition can drive genuine excellence and innovation, but it also guarantees that some participants will predictably fail through no unique fault of their own. This unresolved tension underlies debates about fairness in education, employment, and markets.
economics-resources
global-unspecified
haven
resolved
whether
ethical
allow
competitive
systems
inevitably
produce
both
philosophy-ethics
know
mathematics-logic
determine
possible
open
Global / Unspecified, Global
Democratic systems generally depend on active citizen participation, yet forcing engagement as a moral duty seems to conflict with respecting individual autonomy and personal priorities. This unresolved tension shapes ongoing debates about civic responsibility.
philosophy-ethics
global-unspecified
whether
personal
don
know
humans
have
obligation
remain
politically
engaged
resolved
haven
determine
mathematics-logic
ethical
open
Global / Unspecified, Global
Most people naturally apply different moral standards to close relationships versus strangers, but it's unclear whether this differential treatment is ethically justified or simply an ingrained bias. This unresolved question challenges the idea of a fully impartial ethical framework.
philosophy-ethics
global-unspecified
whether
moral
framework
haven
figured
out
possible
justify
applies
differently
resolved
know
mathematics-logic
determine
ethical
open
Global / Unspecified, Global
Loyalty to friends, family, or groups is widely valued, but it can sometimes require favoring those close to us over what impartial fairness would otherwise demand. This unresolved tension shapes debates over nepotism, favoritism, and personal ethics.
philosophy-ethics
global-unspecified
loyalty
fairness
haven
figured
out
whether
possible
justify
treating
moral
resolved
know
determine
mathematics-logic
ethical
open
Global / Unspecified, Global
Some philosophers argue honesty is an absolute duty, while others believe consequences justify occasional deception, particularly to prevent harm. Real situations in medicine and relationships constantly test where this line actually falls.
health-biology
global-unspecified
haven
figured
out
whether
ever
morally
permissible
lie
someone
own
philosophy-ethics
resolved
know
determine
mathematics-logic
ethical