Gravitational Lensing and Cosmic Measurements

The video discusses the prediction of a supernova in 2015, the role of gravitational lensing in observing it, and the implications for cosmology, particularly in measuring the Hubble constant. It explains how gravitational lensing can cause multiple images of the same event to appear at different times and locations, and how this phenomenon can be used to study the universe's expansion. The video also touches on the challenges of predicting supernovae and the significance of these observations in understanding light and gravity on a cosmic scale.

What marks the end of a star's life cycle if it is more than 8 times the mass of our sun?

• A white dwarf

• A black hole

• A supernova

• A neutron star

How many supernovae can be expected in a galaxy of 100 billion stars per century?

• Ten

• Two

• Fifty

• One

What phenomenon allows us to see the same supernova in multiple locations?

• Dark matter reflection

• Gravitational lensing

• Black hole bending

• Quantum tunneling

What is an Einstein ring?

• A ring of galaxies in a cluster

• A ring of light formed by gravitational lensing

• A ring of dark matter

• A ring of stars around a black hole

What is the name of the galaxy cluster that caused the gravitational lensing of the supernova?

• SP1149

• MACS J1149.5+2223

• Andromeda

• Milky Way

What is one reason for the time delay in observing the supernova images?

• Interference from other galaxies

• Different light paths

• Changes in the supernova's brightness

• Light absorption by dust

What is the Hubble constant used to measure?

• The speed of light

• The mass of galaxies

• The expansion rate of the universe

• The age of stars

Which method of measuring the Hubble constant involves studying the cosmic microwave background?

• Gravitational lensing

• Lambda-CDM model

• Redshift method

• Distance ladder method

What value of the Hubble constant is more in line with the cosmic microwave background measurements?

• 74 km/s/Mpc

• 80 km/s/Mpc

• 67 km/s/Mpc

• 64 km/s/Mpc

What does the narrator reflect on regarding the nature of space?

• Space warps light on multiple trajectories

• Space is fundamentally transparent

• Space is filled with dark matter

• Space is like a solid glass