We don't have a fully general method for solving all classes of partial differential equations.
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Mathematics & Logic
These equations describe everything from heat flow to fluid movement, but many types still lack a general, reliable solving method. Progress here would ripple into physics, engineering, and climate modeling.
Team Humans Club. (2026). Problem WS00355: We don't have a fully general method for solving all classes of partial differential equations.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=355
We haven't proven the exact conditions under which certain infinite series converge to a finite value.
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Mathematics & Logic
Some mathematical series behave predictably, while others sit in ambiguous territory where convergence is difficult to prove definitively. Fully resolving these cases remains an active area of mathematical research.
Team Humans Club. (2026). Problem WS00354: We haven't proven the exact conditions under which certain infinite series converge to a finite value.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=354
We haven't proven a rigorous, complete theory explaining turbulence in fluids mathematically.
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Mathematics & Logic
Turbulent flow, like water rushing through a pipe or air moving over a wing, is notoriously hard to describe with exact mathematics. A complete theory would improve everything from weather prediction to aircraft design.
Team Humans Club. (2026). Problem WS00295: We haven't proven a rigorous, complete theory explaining turbulence in fluids mathematically.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=295
We don't have a general formula predicting exactly how many prime numbers exist below any given number.
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Mathematics & Logic
We have very good approximations, but no exact formula exists that perfectly predicts the count of primes below a chosen number. Improving this approximation remains an active and important area of research.
Team Humans Club. (2026). Problem WS00294: We don't have a general formula predicting exactly how many prime numbers exist below any given number.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=294
We haven't settled whether every sufficiently large even number can always be written as the sum of two prime numbers.
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Mathematics & Logic
This idea, part of an old and famous conjecture, has held true in every case checked so far but has never been proven true for all numbers without exception.
Team Humans Club. (2026). Problem WS00293: We haven't settled whether every sufficiently large even number can always be written as the sum of two prime numbers.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=293
We don't have a complete solution to the traveling salesman problem for very large numbers of locations.
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Mathematics & Logic
Finding the shortest possible route visiting a long list of locations becomes exponentially harder as the list grows, and no fully efficient general solution exists. Logistics, chip design, and delivery networks all run into this limit.
Team Humans Club. (2026). Problem WS00292: We don't have a complete solution to the traveling salesman problem for very large numbers of locations.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=292
We haven't proven whether there are infinitely many twin prime numbers.
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Mathematics & Logic
Twin primes are pairs of prime numbers that differ by only two, and mathematicians strongly suspect there are infinitely many, but nobody has proven it. This remains one of number theory's oldest open questions.
Team Humans Club. (2026). Problem WS00291: We haven't proven whether there are infinitely many twin prime numbers.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=291
We don't know whether P equals NP, or whether some problems are fundamentally harder to solve than to check.
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Mathematics & Logic
If P equaled NP, countless hard problems in logistics, cryptography, and optimization could be solved efficiently, but most computer scientists suspect they can't. This remains the most famous open question in computer science.
#whether#problems#know#equals#some#mathematics-logic
Team Humans Club. (2026). Problem WS01229: We don't know whether P equals NP, or whether some problems are fundamentally harder to solve than to check.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1229
We haven't proven the Riemann Hypothesis, which predicts exactly where the building blocks of prime numbers hide.
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Mathematics & Logic
This conjecture about the zeros of a specific complex function would, if proven, tighten our understanding of how primes are distributed among all integers. It's considered one of the most important unsolved problems in mathematics.
#proven#haven#riemann#hypothesis#predicts#mathematics-logic
Team Humans Club. (2026). Problem WS01230: We haven't proven the Riemann Hypothesis, which predicts exactly where the building blocks of prime numbers hide.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1230
We still don't know if every mathematical statement that seems true can eventually be proven within a single consistent system.
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Mathematics & Logic
Gödel's incompleteness theorems already showed some truths escape any fixed formal system, but the full boundary between provable and unprovable truths remains an active area of exploration. This shapes how we understand the limits of formal reasoning itself.
#system#know#every#mathematical#statement#mathematics-logic
Team Humans Club. (2026). Problem WS01231: We still don't know if every mathematical statement that seems true can eventually be proven within a single consistent system.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1231
We haven't determined whether the number of solutions to certain simple equations in whole numbers is always finite or sometimes infinite.
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Mathematics & Logic
Many Diophantine equations, which ask for whole-number solutions, resist any general method for predicting how many solutions exist. Solving specific cases has taken decades and earned major mathematical prizes.
#solutions#number#equations#whole#haven#mathematics-logic
Team Humans Club. (2026). Problem WS01232: We haven't determined whether the number of solutions to certain simple equations in whole numbers is always finite or sometimes infinite.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1232
We don't know whether every sufficiently large even number can be reached by adding two numbers that are each a prime or one more than a prime.
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Mathematics & Logic
This weaker cousin of Goldbach's Conjecture illustrates how even modest-sounding claims about primes can remain unproven for centuries. It highlights how little we still understand about the raw arithmetic of prime numbers.
#prime#numbers#know#whether#every#mathematics-logic
Team Humans Club. (2026). Problem WS01233: We don't know whether every sufficiently large even number can be reached by adding two numbers that are each a prime or one more than a prime.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1233
We still haven't proven whether there are infinitely many prime numbers of the form found in Mersenne's sequence.
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Mathematics & Logic
Mersenne primes, of the form two raised to a power minus one, are the largest primes ever discovered, but no one has proven that the list never ends. Finding new ones remains an active computational hunt.
#proven#form#mersenne#haven#whether#mathematics-logic
Team Humans Club. (2026). Problem WS01234: We still haven't proven whether there are infinitely many prime numbers of the form found in Mersenne's sequence.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1234
We haven't resolved whether the digits of pi contain every possible finite sequence of numbers somewhere within them.
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Mathematics & Logic
If pi is what mathematicians call 'normal,' every string of digits, including your birthday or an entire book encoded in numbers, would appear infinitely often. No proof exists either way, despite pi's digits being computed to trillions of places.
#digits#every#numbers#haven#resolved#mathematics-logic
Team Humans Club. (2026). Problem WS01235: We haven't resolved whether the digits of pi contain every possible finite sequence of numbers somewhere within them.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1235
We don't know how to efficiently factor extremely large numbers into their prime components.
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Mathematics & Logic
This difficulty is exactly what keeps most modern encryption secure, since multiplying primes together is easy but reversing the process is not. If an efficient method were found, it could upend the security of the internet as we know it.
#know#efficiently#factor#extremely#large#mathematics-logic
Team Humans Club. (2026). Problem WS01236: We don't know how to efficiently factor extremely large numbers into their prime components.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1236
We still haven't determined the exact boundary of how densely objects can be packed into higher-dimensional spaces.
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Mathematics & Logic
Sphere-packing problems are solved for a few specific dimensions, but the general pattern across all possible dimensions remains unknown. This affects fields ranging from error-correcting codes to theoretical physics.
#haven#determined#exact#boundary#densely#mathematics-logic
Team Humans Club. (2026). Problem WS01237: We still haven't determined the exact boundary of how densely objects can be packed into higher-dimensional spaces.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1237
We haven't proven whether chess, in principle, always has a guaranteed winning or drawing strategy for one side from the starting position.
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Mathematics & Logic
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.
#chess#proven#one#haven#whether#mathematics-logic
Team Humans Club. (2026). Problem WS01238: We haven't proven whether chess, in principle, always has a guaranteed winning or drawing strategy for one side from the starting position.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1238
We don't know whether every knot can be told apart from every other knot using a simple, efficient test.
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Mathematics & Logic
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.
#every#knot#know#whether#told#mathematics-logic
Team Humans Club. (2026). Problem WS01239: We don't know whether every knot can be told apart from every other knot using a simple, efficient test.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1239
We still haven't proven the Collatz Conjecture, a strikingly simple rule that seems to always lead back to one.
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Mathematics & Logic
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.
#rule#seems#always#one#haven#mathematics-logic
Team Humans Club. (2026). Problem WS01240: We still haven't proven the Collatz Conjecture, a strikingly simple rule that seems to always lead back to one.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1240
We haven't resolved how many unit squares are needed, at minimum, to tile a square of a given odd size without overlaps or gaps.
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Mathematics & Logic
Certain simple-sounding tiling and packing puzzles remain surprisingly resistant to a complete general solution. These problems test the limits of combinatorics and geometric reasoning.
#haven#resolved#many#unit#squares#mathematics-logic
Team Humans Club. (2026). Problem WS01241: We haven't resolved how many unit squares are needed, at minimum, to tile a square of a given odd size without overlaps or gaps.. World Solve. Retrieved 19 Jul 2026, from https://worldsolve.org/index.php?id=1241