A mysterious force accelerating universal expansion.

How is dark matter different from dark energy?

Dark matter inferred from gravitational effects, dark energy accelerates expansion.

What is the cosmological constant?

A repulsive force explaining universal expansion.

Dark energy tearing apart the universe in the future.

Dark energy, distinct from dark matter, is a mysterious force that makes up 68.5% of the universe's energy and accelerates the universal expansion, counteracting gravity with a repulsive force.
The concept of the cosmological constant, represented by lambda, was introduced by Albert Einstein to maintain a static universe but later explained the universe's expanding nature, with recent theories suggesting that dark energy, represented by lambda, may not be constant, potentially leading to dynamical dark energy theories where its value changes over time and space.

What is dark energy?
A mysterious force accelerating universal expansion.
How is dark matter different from dark energy?
Dark matter inferred from gravitational effects, dark energy accelerates expansion.
What is the cosmological constant?
A repulsive force explaining universal expansion.
What is the "Big Rip" scenario?
Dark energy tearing apart the universe in the future.

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In 1998, astronomers discovered that the universe's expansion was accelerating due to dark energy, a mysterious force making up 68.5% of the universe's energy, distinct from dark matter.
Dark matter, unlike dark energy, doesn't interact with light and is inferred from gravitational effects on galaxies, while dark energy accelerates universal expansion.
Albert Einstein introduced the cosmological constant, lambda, to his equations to maintain a static universe, later realizing the universe was expanding.
Lambda, acting as a repulsive force, explains the universe's accelerating expansion, with a positive lambda value counteracting gravity.
The cosmological constant, representing dark energy, is a mathematical solution based on observed expansion rates, with a value of about 2 x 10^-35 s-2.
Recent observations suggest the cosmological constant may not be constant, potentially leading to dynamical dark energy theories where dark energy changes over time and space.
Dark energy could be viewed as a field, similar to the Higgs field, with particles interacting with matter particles to create an anti-gravitational force, known as the "core" model.
The "Big Rip" scenario predicts a universe torn apart by dark energy's increasing repulsion, eventually disintegrating all matter into fundamental particles, but this is projected to occur billions of years in the future.