Einstein’s Greatest Blunder: Cosmological Constant Explained Quiz

Lambda is the mathematical symbol for the cosmological constant. It represents the energy density of empty space and acts as a pressure that influences how the universe expands or contracts over time.

In the early 20th century, Einstein believed the universe was unchanging. He added Lambda to his equations to provide an outward pressure that would balance the inward pull of gravity, preventing the universe from collapsing.

The correct answer is Vacuum. In modern physics, Lambda is often associated with vacuum energy, meaning that even completely empty space contains a constant amount of energy that affects the cosmic expansion rate.

Options A, B, and D are correct. Lambda acts as an outward push, and unlike matter, its density does not drop when the universe grows. This makes it a primary candidate for explaining why expansion is speeding up.

After Edwin Hubble observed that galaxies were moving away from each other, Einstein realized the universe was not static. He removed Lambda from his equations because he felt he had missed the opportunity to predict the expansion of the universe.

While dark energy is the broad term for the force causing acceleration, the cosmological constant is the specific model where that energy is perfectly uniform and constant throughout all of space and time.

A positive cosmological constant provides a continuous outward pressure. If this force is strong enough to overcome the gravitational pull of all matter, the universe will never stop growing and will eventually become cold and empty.

Scientists look at the most distant objects and the oldest light to measure how the expansion rate has changed. This data allows them to calculate how much Lambda is contributing to the total energy of the cosmos.

Accelerated is the correct term. When the outward pressure of the cosmological constant exceeds the inward pull of matter, the rate at which galaxies move away from each other begins to increase over time.

A negative cosmological constant would act as an attractive force, adding to the pull of gravity. This would eventually cause the expansion of the universe to stop and reverse, leading to a Big Crunch.

This is a unique property of the cosmological constant. Unlike matter or radiation, which spread out and become less dense as space grows, the energy density of Lambda remains constant in every cubic centimeter of space.

This is false. The cosmological constant is a theoretical and observational concept in physics and astronomy. It is studied by observing light from distant galaxies and the cosmic microwave background, not by physical samples from planets.

The Lambda CDM model is the standard model of Big Bang cosmology. It uses Lambda to explain dark energy and CDM to explain the invisible matter that holds galaxies together, forming a complete picture of cosmic evolution.

In the context of HS-ESS1-2, understanding Lambda is essential to explaining how the universe evolved from a single point. It determines the speed at which the early universe grew and how it reached its current state.

Relativity is the correct term. Einstein’s theory of general relativity describes how mass and energy curve space and time. Lambda was a specific term in these equations that allowed for a balance between gravity and the vacuum of space.

In quantum field theory, even a perfect vacuum has a non zero energy level. Physicists believe this inherent energy of space is what Lambda measures on a cosmic scale, providing the pressure for expansion.

This is false. While it is the most popular and simplest model, there are other theories like quintessence, which suggests that the energy of space might change over time rather than remaining constant like Lambda.

By using spectroscopy to find the redshift and combining it with the distance data from standard candles, astronomers can see how the expansion rate has changed, which directly reveals the influence of Lambda.

Data from the Planck satellite and supernova surveys indicate that Lambda is a very small positive number. Though small, it is enough to dominate the expansion of the universe because there is so much empty space.

Cosmology is the scientific study of the large scale properties of the universe as a whole. It uses concepts like the cosmological constant to build evidence based explanations for the evolution of the cosmos from its origin.