DARK ENERGY (Syllabus: GS Paper 3 – Sci and Tech)

Context: A recent release by an international team of researchers unveils the most comprehensive "three-dimensional" map of the universe, offering insights into the enigmatic force of dark energy driving uncontrollable expansion.

Dark Energy

• About: It is an unidentified type of energy that influences the universe on its grandest scales.
• Supernova Observations: Initial evidence for dark energy came from observations of supernovae, revealing the universe's unexpected acceleration in its expansion.
• Contradiction to Previous Assumptions: Before these findings, it was believed that the universe's expansion would gradually slow down due to known forms of matter and energy.
• Characteristics of Space: Dark energy redefines our understanding of space, transforming it from a void into a dynamic, stretchable medium that responds to the presence of energy.
• Expansion Dictated by Energy Forms: Various forms of energy, including matter, radiation, and dark energy, uniquely influence the universe's expansion, leading to a non-uniform expansion rate across different regions of space.
• Balancing Act: Dark energy dominates the universe's energy budget, dictating the overall rate of expansion and necessitating a delicate balance with other forms of energy for the stability of the cosmos.

• Does it Exist?

oAccepted Premise: Since the 1990s, dark energy has been the leading hypothesis to explain the accelerated expansion of the universe.

oOngoing Research: As of 2021, cosmology research continues to actively investigate the fundamental nature and properties of dark energy.

Dark Matter

• About: It is a hypothetical form of matter that is believed to exist in the universe but is invisible and does not interact with light. It makes up over 80% of all matter in the universe.