Understanding the Universe: Dark Matter and Dark Energy
Cosmology is the study of our universe—how it started and how it has changed over time. One of the biggest questions in modern physics is about two mysterious things: dark matter and dark energy. Learning about these topics is really important for students studying Year 13 Physics.
The Big Bang theory tells us that the universe started as a tiny, very dense point about 13.8 billion years ago. After the Big Bang, the universe began to expand. We know the universe is still growing because we can see distant galaxies moving away from us. This is known as redshift.
Dark matter is a strange kind of material. We can't see it because it doesn't give off light or interact with light like other things do. However, we know it's there because it has gravitational effects on things we can see, like stars and galaxies.
For instance, when we look at how fast galaxies spin, it seems like there’s a lot more mass than we can see.
Gravitational Lensing: One way we know dark matter exists is through something called gravitational lensing. This happens when light from faraway galaxies bends around massive objects closer to us. This bending shows that there is extra mass—thought to be dark matter—surrounding those objects.
Cosmic Microwave Background (CMB): Scientists also look at something called the Cosmic Microwave Background, which is leftover energy from the Big Bang. The patterns in this energy tell us there’s a lot of unseen mass affecting how the universe is structured.
Dark energy is another important part of our universe. It acts like a force that causes the universe to expand faster and faster. Observations of distant exploding stars called supernovae show that this expansion is speeding up.
Today’s models of the universe use both dark matter and dark energy to explain how everything works together at a grand scale. The leading model called Lambda Cold Dark Matter (CDM) includes:
In conclusion, dark matter and dark energy are crucial for understanding how our universe functions. They help explain why galaxies spin the way they do and why the universe keeps expanding faster. Students exploring these concepts should think of the universe as a huge, exciting mystery filled with things waiting to be discovered.
Understanding the Universe: Dark Matter and Dark Energy
Cosmology is the study of our universe—how it started and how it has changed over time. One of the biggest questions in modern physics is about two mysterious things: dark matter and dark energy. Learning about these topics is really important for students studying Year 13 Physics.
The Big Bang theory tells us that the universe started as a tiny, very dense point about 13.8 billion years ago. After the Big Bang, the universe began to expand. We know the universe is still growing because we can see distant galaxies moving away from us. This is known as redshift.
Dark matter is a strange kind of material. We can't see it because it doesn't give off light or interact with light like other things do. However, we know it's there because it has gravitational effects on things we can see, like stars and galaxies.
For instance, when we look at how fast galaxies spin, it seems like there’s a lot more mass than we can see.
Gravitational Lensing: One way we know dark matter exists is through something called gravitational lensing. This happens when light from faraway galaxies bends around massive objects closer to us. This bending shows that there is extra mass—thought to be dark matter—surrounding those objects.
Cosmic Microwave Background (CMB): Scientists also look at something called the Cosmic Microwave Background, which is leftover energy from the Big Bang. The patterns in this energy tell us there’s a lot of unseen mass affecting how the universe is structured.
Dark energy is another important part of our universe. It acts like a force that causes the universe to expand faster and faster. Observations of distant exploding stars called supernovae show that this expansion is speeding up.
Today’s models of the universe use both dark matter and dark energy to explain how everything works together at a grand scale. The leading model called Lambda Cold Dark Matter (CDM) includes:
In conclusion, dark matter and dark energy are crucial for understanding how our universe functions. They help explain why galaxies spin the way they do and why the universe keeps expanding faster. Students exploring these concepts should think of the universe as a huge, exciting mystery filled with things waiting to be discovered.