Lambda Cold Dark Matter Theory (LCDM)
Possible uses of this theory in the classroom
Where did the LCDM theory come from?
- Grades 9-12 Physical Science: Topics:
- History of the Universe (Big Bang and universe expansion)
- Galaxy Formation
- Current Events project
- Show students Bolshoi simulation and how it proves LCDM theory correct
- Have a discussion about it
Where do you see the LCDM theory used?
How did I find my research?
- The theory has become the standard model of Big Bang cosmology
- It is being used primarily by modern cosmologists to try and explain what dark matter and dark energy consist of
- You can't see the direct impact of LCDM on your everyday life but if it is true, it is how our galaxy first formed
- Discovery of cosmic microwave background in 1965 confirmed a key prediction in Big Bang cosmology
- During 1970's, pure-baryonic models were assumed but had problems explaining formation of galaxies
- In early 1980's, found that cold dark matter could explain galaxy formation
- Assumes general relativity is the correct theory of gravity
My Trip to NASA
At the Visitor's Complex
The Endeavour Launch
Methods of Inquiry
- Observed aerospace engineers
- Did some work with dark matter and dark energy
- Found the creators
- Reached out to Dr. Primack (Co-author of LCDM)
- Used his resources to obtain information
Heard of LCDM Theory
What is the LCDM Theory?
- While at NASA, I heard about the LCDM theory
- I did not really take the time to understand it
- Always had a love for astronomy and physics
Basic Definition
LCDM stands for:
- Right after Big Bang, universe rapidly inflated in size
- Quantum fluctuations left matter and energy unevenly distributed in universe
- Gravity caused high-density regions to combine into halos of dark matter and ordinary atomic matter
- These halos gave rise to galaxies and clusters of galaxies.
- L= Lambda (greek symbol) referring to dark energy
- Einstein's cosmological constant
- CDM= Cold Dark Matter
- Thus Lambda (dark energy) Cold Dark Matter Theory
References
Who Originated it?
- Published in 1984
- Joel R. Primack, George Blumenthal, and Sandra Moore Faber
- Introduction to Bolshoi Simulations. (n.d). Bolshoi Cosmological Simulations. Retreived from: http://hipacc.ucsc.edu/Bolshoi/
- Lambda-CDM Model. (2014). Wikipedia. Retrieved from: http://en.wikipedia.org/wiki/Lambda-CDM_model
- Naeye, R. (2012). Interview with Joel Primack. Sky and Telescope. Retrieved from: http://www.skyandtelescope.com/sky-and-telescope-magazine/beyond-the-printed-page/interview-with-joel-primack/
- Perlman, D. (2011). Bolshoi Simulator Maps Galaxies' Dark Matter Halos. SF Gate. Retrieved from: http://www.sfgate.com/science/article/Bolshoi-simulator-maps-galaxies-dark-matter-halos-2298611.php
- Primack, J. (2012). The Cosmological Supercomputer. IEEE Spectrum. Retrieved from: http://spectrum.ieee.org/aerospace/astrophysics/the-cosmological-supercomputer
How has the theory changed over the years?
- It has not changed much and is accepted as true thus far
- It is a relatively new theory
- There are some arguments against it such as the fact that there is no way to detect dark matter (Or is there now?)
Bolshoi Simulation
- Most accurate cosmological simulation of the large-scale structure of the universe yet made
- Created on 7th fastest supercomputer in the world at NASA Ames Research Center by Joel Primack and his colleagues.
- First run in 2009, analyzed in 2010-present
- This simulation, if true, proves LCDM theory correct
Sloan Digital Sky Survey verses Bolshoi
The Bolshoi Simulation
Who uses this theory now?
- Modern cosmologists, astrophysicists, and workers at NASA are the primary people who directly use this theory
- The 2011, Physics Nobel Prize winners discovered that the expansion of the universe is speeding up (this has roots in LCDM theory)
- This theory has led to the Bolshoi experiment which is an extension of the LCDM theory and helps prove the theory true.
Most of the Universe is Missing
By: Chelsea Malak