It seems some German scientists have found a new way to produce hydrogen straight from sunlight and water. This is excellent. But it took me a while to see why it is excellent, hence this post; it’s not obvious at first glance.
Brief recap of basic physics: To make hydrogen (and oxygen as a [...]
Entries Tagged as ‘Physics’
August 28, 2008
Thinking about hydrogen
August 26, 2008
Entropy of star formation I
Dr Pournelle asked an interesting question the other day. (His blog uses the technology of 1995, making permalinks difficult, hence the link to his front page.) The question is this: Entropy always increases. Current cosmological theory has the early universe going from an undifferentiated mass of hydrogen with a bit of helium, to stars and [...]
August 15, 2008
Quantum ‘weirdness’
Why is it that every story about a quantum physics experiment seems bound by law to use the word ‘weird’ somewhere? Quantum mechanics is not weird. Human intuition is weird; it evolved for the extremely unusual, special case of ~100-kg objects (okay – conglomerations of atoms; the macro-level ‘objects’ are an illusion) moving (more accurately, [...]
June 25, 2008
Meaning of the Minkowski metric
I found this question about special relativity in my email today:
The mathematical principle behind Minkowski’s formula, as described in the [Wikipedia] article, is quite straightforward and logical, and I understand how come time contracts as space expands and vice versa. I also see how this formula mathematically develops into the Lorentz transformation. My quibble, however, [...]
June 23, 2008
Limits to singularities
No gaming today; physics and economics. In particular, Robin Hanson at Overcoming Bias posts about singularities, which are transitions where the rate of change suddenly changes drastically. He identifies four: Multicellular animals, human brains, farming, and industry. He also expects another one shortly, which seems to me to be extrapolating from four data points, a [...]
