What are the two possible polarizations that describe how a gravitational wave can stretch and squeeze spacetime?

Answer

'plus' (+) and 'cross' ($ imes$)

Gravitational waves have two possible polarizations, referred to as 'plus' (+) and 'cross' ($ imes$), which describe the two fundamental transverse ways the wave strains spacetime.

What are the two possible polarizations that describe how a gravitational wave can stretch and squeeze spacetime?
propagationspacetimewavegravitational wave