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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.


Jul
23
answered Is it better to build a space elevator from GEO down to the surface of the Earth?
Jul
23
revised Velocity of 2 balls with different masses on a moving train after the train brakes
added 50 characters in body
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
I've made some of my comments into an answer in case you want to accept that, or you're welcome to make your own if you prefer.
Jul
22
answered Velocity of 2 balls with different masses on a moving train after the train brakes
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
Although, some people will tell you you shouldn't use $F$ because there isn't "really" a force acting on the balls. But when you get to much more advanced physics (general relativity) you'll find that the use of $F$ in this sort of situation is unavoidable.
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
Yes, the argument in your comment on Akash's answer is correct.
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
I think it's intended as a trick question. If you haven't covered air resistance yet then the answer is "neither of them - they both move at the same speed", and unless your teacher was making some other assumptions that I don't know about, her argument is incorrect. In the train's reference frame they both get the same acceleration, so they move in the same way. It's exactly the same reason why (ignoring air resistance) the two balls would fall at the same speed if dropped from a tall building.
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
@YatharthROCK in the real world, a smooth surface doesn't imply no air resistance, of course - but in the idealised world of physics test questions, air resistance is often ignored unless it's specifically mentioned in the question. "Smooth surface" implies that you should ignore friction between the balls and the surface, and it would be a slightly odd question if they wanted you to ignore friction but take account of air resistance, especially without specifically mentioning it. (Though of course, if the book has covered air resistance recently then it's different.)
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
By the way I tagged it as homework according to the homework policy - but this is a good question according to that policy, so it won't be closed.
Jul
22
revised Velocity of 2 balls with different masses on a moving train after the train brakes
deleted 32 characters in body; edited tags
Jul
22
comment Velocity of 2 balls with different masses on a moving train after the train brakes
Since the question says "kept on the smooth surface", you're probably supposed to assume there are no forces acting on the balls at all.
Jul
21
reviewed Close Are the forces I'm using correct? (ball in air)
Jul
21
reviewed Leave Open Quantum annealing computing
Jul
21
reviewed Leave Open Turning off or tuning the Higgs field
Jul
21
reviewed Close Temperature of rod if end points are different temperature
Jul
18
comment Qubit (Qdit) equivalence with bits/bytes/Kbytes/
...though having said that, qubits do sometimes have the feeling of being equal to two classical bits each. E.g. in quantum teleportation you have to transmit two classical bits in order to transfer the state of one qubit. It's not very straightforward. But if you have 10 qubits, the maximum amount of classical data you can store is 10 bits, so I think one-to-one is the best way to look at it.
Jul
18
comment Qubit (Qdit) equivalence with bits/bytes/Kbytes/
It's one to one. To the extent that bits and qubits can be compared to one another, one bit equals one qubit.
Jul
18
comment How is information related to energy in physics?
I'm pretty sure there's a paper where Jaynes strongly argues against the view that Loschmidt's paradox can be proven without brining in empirical evidence, but I can't seem to find it at the moment. (I've read most of his papers, so it can be hard to remember which one is which.) If I come across it I'll let you know.
Jul
16
comment How is information related to energy in physics?
Jaynes argument for the second law is very explicitly based on an empirical fact. That fact is that we, as experimenters and engineers, are able to directly influence the initial conditions of an experiment, but we can't affect the final conditions except indirectly, by changing the initial conditions. Jaynes' argument says that given this asymmetry, the second law follows. However, this empirical fact in itself is then in need of an explanation, which Jaynes' argument can't help us with, and that's probably where you have to start thinking about the boundary conditions of the universe.
Jul
16
comment Why does wet skin sunburn faster?
Another reason is that if your skin is wet then you probably just washed off all your sunscreen...