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I'm a post-doctoral researcher with a wide range of interests. My career is in complex systems science (or maybe cybernetics) and the origins of life, but I also have research interests in

  • the foundations of statistical mechanics and its relationship to information theory
  • Earth systems science
  • non-equilibrium thermodynamics in general

I'm also generally interested in the foundations of quantum mechanics and in black holes, though I wouldn't say I'm an expert on those things.

It's probably worth noting that despite the fact that my research is in physics-related areas, all my degrees are in other subjects. If I occasionally seem to start talking in an alien language, this is probably why.


Sep
27
revised Is a chain REALLY only as strong as its weakest link
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Sep
27
comment Is a chain REALLY only as strong as its weakest link
This isn't really a case of the thicker string being weaker, though, it's just a case of more force being applied to the stronger string than the weaker one.
Sep
27
comment Disequilibrium during infinitesimal steps of a thermodynamic reversible process & cause of maximum work to be achieved during reversible process?
...this means that the total energy change of the system is the same - the question then is how much of that energy went into heat, and how much went into work? In the case of the lead shot, most of it goes into work - when you remove a piece of shot, the piston lifts the rest of it against gravity, which is work. But it also jiggles the piston around a bit and makes some heat. When you remove a grain of sand, the amount of jiggling is much less and so even more of the energy goes into work. By the time you get to infinitesimal grains, there's no jiggling (and no heat generated) at all.
Sep
27
comment Disequilibrium during infinitesimal steps of a thermodynamic reversible process & cause of maximum work to be achieved during reversible process?
@user36790 after you've removed the 1000 pieces of lead shot, you've removed a total weight of $1000mg$. This has allowed the piston to expand, doing work. After you've removed the 100,000 grains of sand, you've removed a force of $100{,}000\times (m/100)\times g = 1000mg$, the same as for the lead shot. So although the total amount of heat generated by friction goes to zero as the size of the grains decreases, the total change in volume and force stay the same. (to be continued...)
Sep
27
answered Is a chain REALLY only as strong as its weakest link
Sep
26
answered Disequilibrium during infinitesimal steps of a thermodynamic reversible process & cause of maximum work to be achieved during reversible process?
Sep
25
comment Why is the sky never green? It can be blue or orange, and green is in between!
There are definitely some green pixels in that image, but I think if you're actually looking at the sky it's very difficult to perceive it as green, rather than a sort of superposition of orange and blue. I'll have to pay attention to it next time I see a sunset like that.
Sep
25
revised When the low temperture reservoir with negative temperture (Kelvin), such as Ising model, is the efficiency of ideal heat engine larger than 1?
deleted 2 characters in body
Sep
25
answered When the low temperture reservoir with negative temperture (Kelvin), such as Ising model, is the efficiency of ideal heat engine larger than 1?
Sep
24
awarded  Autobiographer
Sep
22
revised Why the self-information is -log(p(m))?
edited body
Sep
22
answered Why the self-information is -log(p(m))?
Sep
18
comment Thermodynamics: heat transfer
No time to write a detailed answer, but in short you're 100% correct, energy flows in both directions, always. The second law applies to the net transfer of hot-to-cold minus cold-to-hot, averaged over time.
Sep
18
answered Is speed an intensive property?
Sep
16
awarded  Necromancer
Sep
16
answered MIcrocanonical and Canonical - The thermodynamic limit
Sep
14
awarded  Nice Question
Sep
12
answered How to do linear stability analysis on this system of ODEs?
Sep
12
comment Entropy / Structure Relations
Order is tricky to define, and I'd suggest you're better off not trying to. Entropy is often said to measure disorder, but I find it better to think of it as measuring, well, entropy. We tend to find it correlates inversely with our intuitive notions of order, but this isn't always true. (For example, is an emulsion more ordered than phase-separated oil and water? My intuition says no, but entropy-as-disorder says yes.) For me the greater insight is attained by understanding entropy for what it is, rather than trying to map it to concepts like order. But that's just my opinion.
Sep
10
awarded  Nice Question