Linearised Theory of GR - 1

What is the main focus of the linearised theory of general relativity?

• Strong gravitational fields

• Weak gravitational fields

• General coordinate invariance

• Quantum effects

In the linearised theory of gravitational waves, the background spacetime metric can be written as

• Minkowski spacetime

• Flat Euclidean spacetime

• Anti-de Sitter spacetime

• de Sitter spacetime

Which type of transformations does the linearised theory of general relativity allow?

• General coordinate transformations

• Gauge transformations

• Lorentz transformations

• Both B and C

Which equation describes the linearised Einstein field equations in vacuum?

• Maxwell's equations

• Wave equation

• Klein-Gordon equation

• Poisson's equation

The condition that specifies the gauge where the gravitational wave perturbation is transverse and traceless is known as

• Hilbert gauge

• Lorentz gauge

• De Donder gauge

• Transverse-traceless gauge

How many independent polarisations characterize gravitational waves?

• 1

• 2

• 3

• 4

The linearised Einstein equations in vacuum outside the source reduce to a wave equation for waves traveling at

• The speed of sound

• The speed of light

• 50 km/h

• The speed of dark energy

In the TT gauge, how many degrees of freedom are left for the gravitational wave perturbation in 4D spacetime?

• 1

• 2

• 3

• 4

The polarization tensor of a gravitational wave represents

• The amplitude of the wave

• The direction of propagation of the wave

• The polarization states of the wave

• The frequency of the wave

The non-zero components of the gravitational wave perturbation in the transverse-traceless gauge are located in

• The plane parallel to the direction of propagation

• The plane orthogonal to the direction of propagation