sgsguru: (Default)
2014-08-03 01:49 pm

Topic for Research -- Catalysts

When you have a chemical reaction, you start out in one energy state and end up in a lower energy state. However, there is an "energy barrier" between the states. This means that you can mix, for example, hydrogen and oxygen gasses without them reacting, until something adds enough energy to go over the barrier. You get that energy back as part of the reaction; it just keeps the reaction from starting. Catalysts work by lowering the energy barrier, usually by providing a bunch of intermediate states that have lower energy barriers than the original reaction. In quantum mechanics, there are two ways of getting past a barrier. You can go over, which requires adding enough energy to climb over the barrier. However, you can also "tunnel" through the barrier *without* adding energy. The probability of tunneling depends on the area (integral) of the barrier, and not on its height. So theoretically, a catalyst could work by reducing the *width* of the barrier instead of its height.
sgsguru: (Default)
2014-04-28 03:52 pm

Topic for Research -- What's At L4 and L5?

In planetary physics, the Lagrange points are points in a two-body system where the gravitational attraction from the two bodies are equal. There are five such points; L1-L3 are unstable while L4 and L5 are stable. The Earth-Moon L4 and L5 points have attracted interest as possible sites for space colonies.

But what's already there? There has only been one space mission through L4 and L5 (the Hiten spacecraft), which found no increase in the amount of interplanetary dust. (That was the only instrument it had.) It seems to me that all sorts of interplanetary flotsam should end up there, from dust to fairly good-sized rocks. Some of them should be visible (via light or radar) from the ground. It would also seem to be a good place to collect samples of interplanetary flotsam; much easier than going all the way out to the asteroid belt.

sgsguru: (Default)
2014-04-28 03:21 pm

Topic for Research -- How Big is the Universe?

How big is the Universe? What's its mass? I don't mean the *visible* universe -- I mean the whole thing. According to current cosmology, immediately after the "big bang", the universe went through a period of "inflation", where space itself expanded far faster than the speed of light. This spread out all of the "wrinkles" in space-time that should have been generated by the Big Bang, so that we see, for example, the cosmic background radiation as being very smooth in all directions.

However, this means that there are parts of the universe that we can't see -- they're "over the horizon". Inflation pushed them to a distance that their light simply can't get to us.

According to the Wikipedia article above, estimates of the size of the total Universe range from 250 times the size of the visible universe to 3×1023 times the size of the visible universe. I'd think that this would be a critical parameter for any "theory of everything". With estimates differing by 21 orders of magnitude, there's obviously room for research.

sgsguru: (Default)
2014-04-28 03:13 pm
Entry tags:

Topics for Research

"Topics For Research" are simply questions that I don't know the answer to, and might be interesting for a research project. Some, I am sure, are questions that were answered a long time ago, but I don't know the proper Magic Words to feed into Google. Some might be worthy of a dissertation.