What is the purpose of ‘evolved Laser Interferometer Space Antenna (eLISA)’ project?

The correct answer is To detect gravitational waves.

Step 1: Understanding eLISA
The evolved Laser Interferometer Space Antenna (eLISA) is a major space-based mission concept spearheaded by the European Space Agency (ESA) in collaboration with NASA. Its primary objective is to build a space-borne observatory capable of measuring ripple effects in spacetime.

Step 2: Mechanism and Science Behind the Project
Gravitational waves are tiny ripples in the fabric of spacetime created by dynamic cosmic events, such as colliding black holes or merging neutron stars. Ground-based detectors like LIGO (Laser Interferometer Gravitational-Wave Observatory) can detect higher-frequency gravitational waves, but they are limited by terrestrial noise. eLISA is designed to operate in space using precision laser interferometry over millions of kilometers to detect low-frequency gravitational waves that cannot be detected from Earth.

Step 3: Conclusion
Therefore, the fundamental purpose of the eLISA project is to detect gravitational waves in space.