Thread: Imaginary physics

There have been quite a few of these abstract time threads recently. I recently encountered the concept of "imaginary time" as opposed to "real time". Some guy's giving lectures about quantum stuff in relation to earth sciences at uni, one of which that caught my attention is called:

"The equivalence between classical diffusion processes and quantum dynamics in imaginary-time: the Fokker-Planck equation."

Does anybody know anything about imaginary time? I've encountered the use of complex numbers in seismics, to explain evanescent surface waves formed by super critical waves at a free surface. The concept seemed very strange and I gave up trying to understand as anything more than mathematics for the sake of convenience. I would appreciate it if anyone could give some precious insight into the physics of the imaginary plane - preferrably a qualitative insight if such a thing exists.

Perhpas you've encountered it in other fields too??

Cheers

The distance between 2 objects is invariant no matter were you are measuring. Even if time is included. Guess the rest.

I've bumped into it, billards. I think it's total @*##$+!

http://en.wikipedia.org/wiki/Imaginary_time

I see it's from stephen hawking, I'll file it along with 'imaginary hawking radiation'.

I think it's interesting. It doesn't immediately seem right to have imaginary time, but the same goes for the seismics and that has real application - it explains surface waves by continuum mechanics.

If it explains stuff then that's all you can ask for. I think it's useful, but I admit the whole concept is completely counterintuitive.

Farsight, I'm not surprised you think it's @#!$, wasn't it you who thinks that time doesn't even exist??

Well just remember is seems only to 'explain' the incomplete theories in QM.

What I am trying to say is, if you come up with a theory that does not quite fit, then add in a fudge factor to explain the error, then give it some exotic name, if it is something that cannot be proven or disproven then you have a winner....

E.G Hawking radiation, it cannot be disputed or proven, it's a fudge with no evidence to support it.

AT the end of the day, it is perfectly possible that mathematics, cannot explain the universe, especially if the laws are not constant.

Who is to say for example that the pull of gravity is directly proportional to mass? supposing gravity is the result of particle interaction, thus when you take all the particles to bits, they (individually) lose their pull? (hence you won't find a 'graviton').

At the other end it may be that ever increasing mass gets to a point where gravity cannot increase - becomes saturated...

Not suggesting either of these is actually true maybe newton's laws of gravity only work over a limited range of mass which is beyond us to measure. Maybe above a certain mass gravity exponentially rises? or has a limit at which it can attract other atoms.

Evertime a new theory is proven wrong, it get's 'fudged' to sav the reputation of the founder, in the past it has been a detractor to progress...

Originally Posted by Megabrain

Well just remember is seems only to 'explain' the incomplete theories in QM.

doesn't special relativity use imaginary numbers in relation to the time dimention, thats not entirely an incomplete theory.

and i thought imaginary time only made the equations in QM simpler, as opposed to actually explaining anything.

either way i think its unfair to dismiss mathematical concepts on account of the person using them.

Imaginary time, is a perspective of time relative to the visible axis to the viewer.
We(humans) for example, see time as 1dimensional (we just see 1 point which changes constantly).
Why we just experience 1time dimension is another question.
Lets say time is 3d, then what you would exiperience as time, is imaginary time.

I beleve that time is 3dimensional and space 6 but I havent proven it yet.

Hmmm, interesting. In classical diffusion, from Fick's laws we predict that if you drop a bottle of ink into an ocean after some large amount of time the ink molecules will spread out evenly. Whilst this seems true intuitively the laws also predict that after a small amount of time, maybe one second, one of the molecules will be an impossibly far distance from where the ink was first dropped. Because the law is purely statistical there seems to be no way to remove this blunder, however it also seems that this blunder is insignificant in the grand scheme of things.
Would it be possible to remove this blunder by considering some kind of correcting process that occurs in imaginary time?? I honestly have no idea...

What is the purpose of using the imaginary plane??