# Freak waves

1. Aug 7, 2003

### meemoe_uk

Wow!
I just heard that freak ocean waves can only be explained with the schrodinger wave equation! Brilliant! Real waves producing wave patterns that were thought impossible in classical mechanics.
Of course, once scientists figure out exactly how real waves can do this, they can then say the same thing is going on with the electron wave. i.e. explain quantum waves with classical waves!!! REVOLUTION!!
What a slap in the face for old physicists. I always knew they were too conservative. John Gribbin said that the trend in physics has been to apply quantum theory rather than to explore the reasons behind it's strange behaviour. Well, looks like he was right.
And who is to thank for this revolution? The hundreds of theorectical physics whose research into daft superstring theory has cost countless millions over the last 15 years? No!, a bunch of mad old seadogs clinging to a piece of wood out in the middle of the atlantic shouting " that wave that sunk my boat was 30m high! ", and everyone else didnt believe them and said " yeah, and yesterday you said you caught a fish which was so big! ".
lol
classic.
It really shouldnt suprise anyone that the next revolution in physics was initiated by fisherman and researched by the shipping industry. A noobie might have thought a physicist would be the one, but then phyisicists are so conservative as to crush any new idea. And if any physicist claims he can explain quantum waves with classical physics, he gets put in a straight jacket, and no-one will ever take him seriously again.
Hmm, does anyone know about the physics of freak waves?

2. Aug 7, 2003

### futz

Umm, your post seems a little over dramatic.

Freak waves are basically an example of the highly non-linear
and unpredictable processes going on in the ocean. The fact
that a non-linear Schrodinger (NLS) equation can be adapted to
explain it doesn't seem surprising. Ultimately, a wave is a wave,
whether it be in the quantum or classicle regime.

3. Aug 7, 2003

### LURCH

Meemoe_UK, where did you here that only Schrodinger wave equations can explain these waves? I've heard about these waves since childhood, and the explanation was never said to be elusive before (not that I ever heard, anyway).

4. Aug 8, 2003

### meemoe_uk

Hi futz and lurch. I saw it on a TV program called horizon. It said that for along time the ocean wave patterns were thought to be linear. Only recently have they decided that ocean waves can be non-linear. A researcher who was familiar with the schrodnger waves reckonised ocean waves to resemble schrodinger waves.
A model he built built from schrodinger equation showed a big wave which nicked energy out of neigbouring waves. But I dont think he knew exactly how ocean waves do this, but they do.

5. Aug 9, 2003

### zoobyshoe

crossed the Atlantic in a tiny
sailboat. Partway across he was
capsized by a 15 foot wave that
came out of an otherwise calm
ocean on a clear day.
____He refered to it as a "rogue
wave" and explained it as the
result of larger than normal waves
coming from different sources but
more or less parallel happening
to meet at the same place where
they joined up by simple addition.
I don't know if this was just the
these waves at the time or if
this had been demonstrated to be
true.
The strange thing is there are also reports of rogue troughs: deep, ship capsizing wave troughs
roving wild. I find that thought
more creepy than the rogue waves.
-zooby

6. Aug 9, 2003

### MathematicalPhysicist

7. Aug 10, 2003

### meemoe_uk

thx lqg, very useful for reference.
I like the bit where Al osborne says " nobody would take it seriously ". But when we consider freak waves, the theory becomes unsuprising, i.e. physicists say "oh well that was obvious ".
Hmm, well if it was so obvious why did they have to wait till the evidence was there? Main stream theorectical physics opinion scores 0/10 for prediction of "unsuprising result".
Well, thats if what futz reckons is true.
I beg to differ. I think it's very strange and interesting new link between quatum and real wave mechanics, I'm sure that further research into it will produce some very interesting new understandings of waves.

8. Aug 10, 2003

### plus

First model of wave behaviour is linear. This applies well in deep seas and small waves. The second model is the stokes wave, and this applies very well to most situations. I cannot see the need for quantum effects to be brought in.
A large wave occurs when the peaks and troughs of two or more different waves coincide. I still fail to see the need for quantum effects. Could you explain your idea a little more as currently it seems as if you have read an overhyped newspaper article and believed it.

9. Aug 10, 2003

### Sonty

I'm guessing the next big thing will be a wave crossing Saudi Arabia from the Red Sea to the Persian Gulf because of the tunnel effect?

10. Aug 10, 2003

### Andy

Isnt a rogue trough just the gap in between 2 large waves? I have never heard of these rogue troughs before, but i have heard about the rogue waves and i also watched the same programme on horizon.

11. Aug 10, 2003

### meemoe_uk

Plus,
this isnt my idea, it's Al Osbourn's. If you think his idea is rubbish then tell him not me. You and futz and the legion of physicsforums sarcy guys which are beginning to swarm over this topic should set up the anti Al Osbourn society, whereby you tell him all his ideas are uninteresting, trivial implications of F=ma, and the only reason it took physicists till 1995 to look his idea, was because it was so boring and pointless.
In the meantime you can tell us about Stokes waves, which I don`t know about.

12. Aug 10, 2003

### zoobyshoe

Andy,

Apparently rogue troughs are not
just the troughs accompanying
rogue waves, but a separate phen-
omenon unto themselves. Here is a
link to site I found that desc-
ribes both in detail:

Bluewater's Newsletter #7 - Waves, wind & weather

-zoob

13. Aug 10, 2003

### Andy

Yea thanks for that, that was quite an interesting read. The asme kinda content as was int he Horizon programme but they also went into rogue troughs which was cool.

14. Aug 11, 2003

### FZ+

Yeah I saw that TV program as well.... Horizon on BBC 2 wasn't it?

Well.... IMHO, the program didn't really explain very well. The wave thing is actually an exhibition of chaos in a fluid system. I'm sure you all heard of the butterfly effect? Well... this is like that.

The traditional, linear models of the waves assume that as a linear equation, small perturbations to the system will stay small. For example, on the computer screen, the variables are only stored to 16bits or whatever, and in the real world, the density etc of the water isn't exactly uniform. The traditional model assumes that these tiny flaws don't matter.
Big mistake.

In reality, the waves have friction between the particles, and little other things that give it a non-linear aspect. (in terms of the equations you would use the describe it) This is where the schrodinger's equation comes in, as those have non-linear aspects that happen to match up to the sort of behaviour real waves exhibit. (This ties into the concept of Universality, or different systems showing same qualitative behaviour)

The non-linear wave equation happens to approximate as a linear equation when certain factors are met. In this case, when the wind speed is low. But, when we don't have these factors, we get into chaotic motion. And the thing about chaotic motion is that small flaws don't disappear, but accumulate to dominate the system. This is how you see the waves exhibit slight wobbles, which grow greatly. The original model was just a special case.

I think the above is right. Someone check it?

15. Aug 12, 2003

### MathematicalPhysicist

arent the waves particles and thus the friction occurs between waves and particles are actually between waves and waves?