How Many Galaxies Are Moving Away From Us Faster Than Light?

TL;DR

Determine that 97% of galaxies move away from us slower than light.

Transcript

okay this is the solution to the problem I posed in the last video you haven't seen that video yet click here to go watch it these questions about the calculating the proportion of galaxies in the observable universe that's moving away from us faster than the speed of light and to solve this we need a few numbers so first of all this is a diagram o... Read More

Key Insights

• 🙂 The observable universe has a radius of 46 billion light-years.
• ☠️ The cosmic expansion rate is 70 kilometers per second per megaparsec.
• 🙂 The speed of light is crucial in determining the limit at which galaxies move away.
• 🔇 Calculating proportions requires converting distance measures and comparing volumes.
• 🙂 Only 2.8% of galaxies in the observable universe move faster than light.
• 👮 Understanding the speed limit of galaxies provides insights into the laws governing the universe.
• 🆘 Accurate calculations help clarify the distribution of galaxies and their movement patterns.

Questions & Answers

Q: How is the radius where galaxies move faster than light calculated?

The radius is found by dividing the speed of light by the cosmic expansion rate and converting it to light-years for comparison, demonstrating the speed limit effect.

Q: What is the significance of finding the proportion of galaxies moving faster than light?

It shows that only 2.8% of galaxies in the observable universe are moving away from us faster than light, reinforcing the laws of physics.

Q: Why is it essential to consider volumes when comparing the proportion of galaxies?

Comparing volumes rather than areas accounts for the true distribution of galaxies, providing a more accurate representation of the cosmic expansion.

Q: How does the calculation methodology impact our understanding of the universe?

By showing that the vast majority of galaxies adhere to the laws of physics, it supports our understanding of how the universe functions and expands.

Summary & Key Takeaways

• Explained how to calculate the proportion of galaxies moving faster than the speed of light.

• Steps detailed include finding the radius and converting it into light-years.

• Found that 97% of galaxies in the observable universe move slower than the speed of light.