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Intermediate Math Challenge  June 2018
Summer is coming and brings a new intermediate math challenge! Enjoy! If you find the problems difficult to solve don't be disappointed! Just check our other basic level math challenge thread! 
Methane and Organic Molecules on Mars
Curiosity has found seasonal occurrences of methane and some organic molecules on Mars. Both or possible indicators of carbon based life processes, but can have other nonbiological explanations. Methane has been intermittently found previously on Mars. However, lacking a continuous long term record the seasonal variations were not obvious. The seasonal variation could be explained by either biological... 
Basic Math Challenge  June 2018
Summer is coming and brings a new basic math challenge! Enjoy! For more advanced problems you can check our other intermediate level math challenge thread! 
Maxwell's equations and QFT
I have been wondering about the validity of Maxwell's equations in quantum physics. I looked in the internet and it seems from what I understood that: Maxwell's equations are valid for any situation, classical or quantum. In fact, maybe it holds more legitimacy than Schrodinger equation since it is a relativistic (invariant) set of equations... 
MiniBooNE results at 6.1 sigma
New evidence in the search for the 'sterile' neutrino. Can someone comment on this please. 
Challenges for artificial intelligence
Here I would like to see interesting challenges for artificial intelligence, which seem very hard for AI and yet in the spirit of what AI usually does. Here is my proposal: Let us feed the machine with a big sample (containing, say, a million numbers) of prime numbers and a big sample of nonprime numbers, without feeding it with a general definition of the prime number... 
Twostage electron wakefield acceleration
The energy of electronpositron colliders is limited by the acceleration gradient (energy per distance) and the length of the accelerator (=the cost). In the past the energy mainly increased from making accelerators larger. Much larger accelerators than today get prohibitively expensive, however. More compact designs could keep them affordable. While conventional cavities still make some progress... 
Area of a circle without calculus
π is defined by the ratio of the circumference (R) of a circle to its diameter. The area of the circle is πR². Can this be derived without calculus (or Archimedes method)? 
CMF bulletproof body armor
The CMF armor on collision literally converts the projectile into small particles, spraying out. This is interesting and definitely not my area. Questions: the particles resulting from the hit have to have kinetic energy, if some particles are redirected to unprotected area (example: projectile hits high, just above the top of the sternum, redirect up into the lower jaw), are they a problem? 
Best Temperature of Water For Rinsing Dishes?
What is the best temperature water for rinsing dishes? I've googled this question, and gotten many answers, very few of which have any rational basis for them whatsoever. For example, some people say that it's better to use hot water, because the soap dissolves better in hot water. However, it's not at all clear to me that dissolving is the underlying mechanism for getting rid of the soap... 
Is there a plan for a search for nearby black holes?
Extrapolating to a sphere centered on Earth with a 100 ly radius, this sphere should contain about 625 stars bigger than red dwarfs and 8 black holes, of which about 4 would be in binary systems. Systematically observing the Doppler shifts for these 625 stars over a period of time should detect any invisible massive companions. Is such a search currently happening or planned? 
Asymptotic Safety for Quantum Gravity
Sabine Hossenfelder recently wrote about an old theory of quantum gravity due to Weinberg: asymptotically safe quantum gravity. Is anyone familiar with this idea? What I couldn't figure out from the article is whether asymptotic safety is an approach to making consistent quantum field theories, or whether some quantum field theories just happen to be asymptotically safe... 
Teaching Economics Without Calculus
Just a quick question. Can you really teach economics without calculus? Reviewing it now just to refresh my memory since we have a budget being delivered tomorrow here in Aus. I have reached the point where it is proven that maximizing overall profit is different from profit per unit of whatever you are considering  you can maximize one or the other  but not necessarily both... 
A couple of links about, not from science
We repeatedly receive some fundamental questions, some of them of philosophical nature, which we're not very keen to answer  not because they weren't legitimate questions, but because we made the experience, that they simply lead nowhere, and, I'll have to admit, because of the lack of knowledge what philosophers already had written about it... 
Seeking a cheap wide mouthed jar capable withstanding vacuum
I'm looking for a cheap, wide mouthed jar capable of withstanding moderate vacuum (up to 2930" Hg). The jar I've currently been using is like this one with a rubber stopper and plumbing valve in place to hold vacuum once evacuated, which works well, but I now need something in a 34" width...
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