Are waves just curves that wobble?

We can view gravity as a "field" that permeates space - the gravitational field.

In the vicinity of the Sun, this gravitational field takes on more extreme values, so that you have to use a powerful rocket to get from Earth to Pluto (further away from the Sun). This effect is due to the mass of the Sun, bending space-time.

As a result of this gravitational field, the planets follow elliptical orbits around the Sun.

Mass tells space-time how to curve, and space-time tells mass how to move.

This "steady" gravitational field around the Sun and Earth follows Newton's laws very closely - you have to look

*very* closely at the orbit of Mercury to see a very small divergence from Newton's gravity. (This small effect is due to time dilation. Gravitational waves, which are the subject of

*this* thread are far more subtle again.)

However, one implication of Einsteins General Theory of Relativity (published a year later, in 1916) was that if you have very intense

*accelerating* gravitational fields (such as surround closely orbiting black holes or neutron stars), some of the orbital energy is carried away as "ripples" on the gravitational field. This is what we call gravitational waves.

The 1993 Nobel prize in Physics was awarded for discovering a

pulsar (in a pair of neutron stars) whose orbit reflects Einsteins prediction. The LIGO team are hoping they will win another one....

Gravitational waves are not totally strange. We are familiar with another field that permeates space - the electromagnetic field. You can have a "steady" field from a battery or a bar magnet. Or you can accelerate the electric charges, which causes "ripples" on the electromagnetic field, carrying energy away from the source. This was predicted by Maxwell, and we now call it radio, X-Rays and light. Maxwell's work laid some of the foundations for Einstein's work.

And do the gravitational waves detected by the LIGO wibbly wobbly detector disprove the existence of Einstein?

They don't change the existence of Einstein the man, or his theory. Assuming this observation holds up to further scrutiny:

**What he got right**: Gravitational waves do exist (but we've sort of known that since 1993; this gives direct detection of it)

**Another thing he got right**: The effect is *very* subtle. We are talking about displacements of less than the diameter of a proton in 4km.

**One thing he got ***wrong*: He thought the effect was *so* subtle that we would *never* detect them. It took 100 years of technological advance, spending a billion dollars, and the existance of black holes (they have a *very* intense gravitational field; Einstein wasn't entirely sure such things could exist, since his theory started producing infinities when you got too close).