Lex Fridman plays with crystals

TL;DR

Using polarizers and birefringent crystals, polarimeters can analyze and change the amount of polarization in light, which is essential in detecting cosmic photons in refracting telescopes.

Transcript

and uh i couldn't bring my my polarized sunglasses here so i brought these actual polarizers here so if you take this and put in front of your telescope there you have now made a polarimeter you have made a polarization sensitive telescope now you may not be able to immediately know how you would use such a thing but one way to think about now take... Read More

Key Insights

• 👻 Polarimeters can be created using polarizers, allowing for the analysis and manipulation of polarization in telescopes.
• 🙂 Birefringent crystals, like calcite, separate light based on polarization and enable polarization analysis.
• 🕵️ Polarimeters are essential in refracting telescopes to detect cosmic photons.
• 🙂 The human eye can slightly detect polarization, but the intensity and color of light play a more significant role in vision.
• 🙂 Polarimeters in telescopes utilize superconductors and balometers for detecting polarized light at low temperatures and vacuum conditions.
• 🔅 Polarimeters operate in the microwave region of the electromagnetic spectrum, where cosmic photons are brightest.
• 💱 Quadrupolar patterns in intensity changes occur when rotating polarizers due to the spin property of photons.

Questions & Answers

Q: How can polarizers be used to create a polarimeter with a telescope?

By placing polarizers in front of a telescope, light passing through them can be polarized, allowing for the analysis and manipulation of the light's polarization.

Q: What is the significance of the quadrupolar pattern observed when rotating polarizers?

The quadrupolar pattern, with bright-dim-bright-dim intensity changes, occurs due to the spin one field property of photons and the axis at which the electric field of light oscillates.

Q: What is the role of birefringent crystals, specifically calcite, in polarization analysis?

Birefringent crystals separate unpolarized light into two different directions based on their polarization, creating double images and enabling the analysis of polarization.

Q: How are polarimeters used in refracting telescopes to detect cosmic photons?

Polarimeters in refracting telescopes analyze the polarization of light, which is crucial in detecting cosmic photons. The detectors used are made of superconductors and balometers operating at extremely low temperatures and vacuum conditions.

Summary & Key Takeaways

• By placing polarizers in front of a telescope, one can create a polarimeter, which can analyze and change the polarization of light.

• Birefringent crystals, such as calcite, can separate light based on its polarization, creating double images and allowing for polarization analysis.

• Polarimeters are used in refracting telescopes to detect cosmic photons, with detectors made of superconductors and balometers operating at extremely low temperatures and vacuum conditions.