Gravitational Waves – Ripples in Space-time Continuum

Gravitational waves are ripples in space time continuum which was seen by Albert Einstein in his general theory of relativity. These are ripples that carry energy across the universe and were predicted to exist as a consequence of Einstein General Theory of Relativity in 1916.

Though there is a strong evidence of its existence, gravitational waves has not been directly detected earlier since they are minuscule which is a million times smaller than an atom.

They seem like tiny waves on a lake far away and the lake’s surface looks glassy smooth and the details of the surface can be seen only when very close to it.Einstein, in the year 1916, discovered a mathematical way to explain gravity and called it his general theory of relativity.

This theory relied on a set of coordinates which described the combination of space and time known as the space time continuum.



Warping of Matter and Energy – Force of Gravity

Since matter and energy warp the space time continuum like heavy weight on a mattress, the warping thus creates the force of gravity and gravitational waves are ripples in the space time continuum.

General relativity shows us how gravity can affect time which should be taken into account by satnav to inform where you are. A telescope at the South Pole known as Bicep – Background Imaging of Cosmic Extragalactic Polarisation, has been looking out for evidence of gravitational waves by detecting subtle property of the cosmic microwave background radiation.

The radiation which was produced in the big bang was originally discovered by American scientist in the year 1964 with the help of radio telescope and has been called as the `echo’, of the big bang. The large scale polarisation of this microwave had been measured by Bicep. Primordial gravitational waves only can imprint such pattern if they have been amplified by inflation.

Curvature of Space-time 

According to Einstein’s theory of general relativity, gravity has been treated as a phenomenon, the outcome of the curvature of space time and this curvature is the result of the presence of mass. The more mass that is contained within a volume of space, the greater is the curvature of space-time at the boundary of the volume.

When the objects with mass move around in space-time, the curvature also changes to reflect the changed location of these objects.

In some situations, accelerating objects may generate changes in this curvature propagating outwards at the speed of light like a wave and these propagating situations are known to be gravitational waves.

Effects of Passing Gravitational Wave

As these gravitational wave passes far away, an observer will find space-time distorted due to the effects of strain and the distance between free objects may increase and decrease rhythmically as the wave may pass at a frequency which corresponds to the wave despite free objects not being subjected to an unbalanced force.

 The effect of the magnitude decreases inversely with distance from the source. Effects of passing gravitational wave can be seen by imagining a flat region of space-time with that of a group of motionless test particle lying in a plane and as the gravitational wave passes through the particles along a line which is perpendicular to the plane of the particles, the particles tend to follow the distortion in space-time.