Math Hobbies?

I'd like to find stuff like that too. For now, I've been playing Brain Challenge on my phone a lot lately. There are some math problems on it.

 

If you mean a hobby that you can do anywhere there's always sudoku...

Do you need this for something or are you just trying to stay sharp?

 

Does the rubiks cube count? I cheated though, I watched a video on how to solve the damn thing.

 

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The Invariant Set Hypothesis proposes that states of physical reality belong to, and are governed by, a non-computable fractal subset I of state space, invariant under the action of some subordinate deterministic causal dynamics D. The Invariant Set Hypothesis is motivated by key results in nonlinear dynamical-systems theory, and black-hole thermodynamics. The elements of a reformulation of quantum theory are developed using two key properties of I: sparseness and self-similarity. Sparseness is used to relate counter factual states to points not on I thus providing a basis for understanding the essential contextuality of quantum physics. Self similarity is used to relate the quantum state to oscillating coarse-grain probability mixtures based on fractal partitions of I, thus providing the basis for understanding the notion of quantum coherence. Combining these, an entirely analysis is given of the standard "mysteries" of quantum theory: superposition, nonlocality, measurement, emergence of classicality, the ontology of uncertainty and so on. It is proposed that gravity plays a key role in generating the fractal geometry of I. Since quantum theory does not itself recognize the existence of such a state-space geometry, the results here suggest that attempts to formulate unified theories of physics within a quantum theoretic framework are misguided; rather, a successful quantum theory of gravity should unify the causal non-euclidean geometry of space time with the a-temporal fractal geometry of state space.


Next Big Future
This is real, folks!
Just a hunch...Reading

 

Divide by zero

 

I know you said you don't want to get stuck on a computer on, but i think Project Euler is kinda fun. I've only started on it (problem 10 of 200 something), but it's a good way to kill some time. Knowing Matlab or Mathematica helps, but you can probably get away with excel and some scripts.

 

I guess you could calculate for pi.

If I remeber correctly I think it's circumference of a circle divided by the diameter. Let me know when you get an answer.

 

brain needs exercise too.

 

Read something on logic.

 

You can try to solve the 3n + 1 problem, which I've been working on for about 15 years.

It's a two part algorithm. Take any positive number.
1) If it's even, divide by 2
2) If it's odd, multiply by 3 and add 1

Repeat this process until you reach the number 1.

So far every number fed into this algorithm ends up at 1, but it yet to be proven why. I have notebooks filled with attempts at proving this to no avail.

Still it's a fun mathematical exercise that you can do in your head if you want something to work on.

A fun problem to give someone else you don't care for is the trisector problem. With a compass and a ruler, attempt to trisect an angle. This has been proven mathematically impossible, but I once watched a lecture by the professor who proved it wasn't possible. He said he gets thousands of letters a year by people who devised complex attempts at a rebuttal. He said it was a pain, but he enjoyed taking the time to find the flaw in their solutions and writing them back about it.

 

Buy a copy of Mathematica... do whatever you want... graph, proofs, analyze, chart, pull from databases, etc.