Recent content by Gulli

So it would appear as generating free energy but it would really be tapping into the energy of the wormhole? Does this energy come from the device that is keeping the wormhole open (meaning it would take more energy to keep a wormhole open if heavy objects pass through it even though the radius...

Would wormholes transmit gravity, if so how? Seeing as wormholes transmitting gravity would prevent them from being used as a perpetual motion device, generating increasingly more kinetic energy, the way they are in the video game "Portal", and since they would transmit matter, it would stand to...

I did a quick test in Matlab to be sure, but as I suspected the exponentials don't take much time to calculate, drawing random numbers takes up >10x more time, so this inefficiency with exponentials didn't matter too much. P.S. I passed the course.

Thanks. No, I didn't define the temperature any different, the heat bath method does get worse at high temperatures, but those temperatures are well above the critical temperature of the metropolis method, but maybe it has something to do with my lattice only being 100x100. I know, at...

That's how I defined a lattice sweep when trying out random selection. I allow for up to 1000 sweeps before I quit the algorith. So you're saying it really doesn't matter whether I sweep systematically or select randomly? I suspected I wasn't the first to think of such things, though what...

Well, I've now successfully implemented bith methods (Metropolis seems to be faster, I think because its steps don't always require computing an exponential). Rather than randomly choosing spins both methods systematically go though all spins in my implementation because drawing random...

I think I got the heat bath method working now, your replies has been very helpful and I found another mistake in the book (the author switched mixed things up again) that kept me from implementing the heat bath method succesfully. I'll never use that book again: it's the second edition but it...

Yes, that's it. I see, if the numbers work out then you could be right. My assignment is to play around with the Ising model using Monte Carlo and simulate ferromagnetism. Testing whether the extra iterations required by correlation between steps negate time saved by not having to choose...

Thanks for your reply. My book "Introduction to Statistical Physics" (Kerson Huang) says 'It can be shown that one step in the heat bath method is equivalent to an infinite number of Metropolis steps.' It and other sources say the heat bath method is supposed to be much faster and only works...

I'm trying to simulate a 100x100 Ising model in matlab. So far I've tried the metropolis method (which seems to work), but I'm having problems with the heat bath method. I'm not sure how it's supposed to work (I can't get the spins to all take the same +1 or -1 value even at really low...

How about this: the Higgs mechanism gives rest mass to all particles except photons and gluons (that I know of). Particles that don't get rest mass from the Higgs mechanism always travel at the speed of light and don't have conventional inertial mass: they can't be made to move faster or slower...

Yes, that's the kind of energy I was talking about. Don't they have effective inertial mass (E/c^2), seeing as they are a source of gravity and gravitational and inertial mass are supposed to be equal? also, something's got to give: if gluons don't have inertial mass themselves how can they...

Photons (and gluons) with non-zero inertial mass would solve my question, but since they don't couple to the Higgs field, what is the origin of their inertial mass? So the way I see it now is this: an elementary particle that is standing still (relative to the observer and all that) has zero...

I know it does, but what's the mechanism (apart from the Higgs mechanism for the rest mass)? How does the interaction through massless photons between an electron and a proton make a hydrogen atom more difficult to move around than separate protons and electrons?

I am, but how would that answer my question?