Source of light in Michelson-Morley experiment

Click For Summary
SUMMARY

The Michelson-Morley experiment utilized a light source that produced yellow light, likely from sodium, to measure the effects of ether drift rather than directly determining the speed of light. The experiment aimed to assess the relative speed of the ether against the Earth, with Michelson employing white light for subsequent measurements. The use of an Argand burner was mentioned as a potential source for the sodium light, which is characterized by its distinct yellow wavelength. The discussion highlights the historical context and methodologies employed in the experiment, referencing key texts for further understanding.

PREREQUISITES
  • Understanding of the Michelson-Morley experiment
  • Familiarity with the concept of ether drift
  • Knowledge of sodium light and its spectral characteristics
  • Basic principles of optical interference
NEXT STEPS
  • Research the historical significance of the Michelson-Morley experiment
  • Study the properties of sodium light and its application in optical experiments
  • Explore the concept of ether and its implications in physics
  • Learn about optical interference patterns and their measurement techniques
USEFUL FOR

Physicists, historians of science, and students studying the foundations of modern physics will benefit from this discussion, particularly those interested in the evolution of light measurement techniques and the implications of the Michelson-Morley experiment.

nikolafmf
Messages
112
Reaction score
0
Hi

I wonder if anyone can tell me what was the source of light Michelson and Morley used when they did the experiment(s) to measure the (difference of) speed of light in different directions? And can it be done with sunlight? Young observed interference patterns with sunlight in 1801 in double-slit experiments. Nikola
 
Science news on Phys.org
https://www.aip.org/history/exhibits/gap/Michelson/Michelson.html#michelson1

Zz.
 
Michelson was not determining the speed of light he was determining the effects of the ether drift (wind) of Fresnel's optical ether, composed of matter (Michelson, p. 120) (Michelson-Morley, p. 334).
 
ZapperZ said:
https://www.aip.org/history/exhibits/gap/Michelson/Michelson.html#michelson1

Zz.

Thank you very much.

As far as I can see, he uses the wavelength of yellow light in his calculations, but doesn't' state what is the source of light?
 
carl susumu said:
Michelson was not determining the speed of light he was determining the effects of the ether drift (wind) of Fresnel's optical ether, composed of matter (Michelson, p. 120) (Michelson-Morley, p. 334).

I see, it was my mistake. He was determining the relative speed between the ether and the Earth, as far as I can see. So he found that it should be much less than Earth's orbital speed.
 
Yes, I'd never heard of an argand burner before.
As far as I can see he does not say what the source of his sodium light was. Perhaps he just put some salt in the flame? Since it seems he then returned to using white light for the measurements, some such temporary expedient seems plausible.
 
nikolafmf said:
Thank you very much.

As far as I can see, he uses the wavelength of yellow light in his calculations, but doesn't' state what is the source of light?

As best I can tell, salt crystals could be burned in the lamp- Sodium produces a bright yellow light from the Sodium D lines, which were known at least since Fraunhofer. The lamp was probably also outfitted with a slit (Mathven screen?) to increase fringe visibility.
 

Similar threads

High School Purity of Interference Pattern in a Classical Double-slit Experiment
  • · Replies 23 ·
Replies
23
Views
2K
High School Did Thomas Young Misinterpret His Double Slit Experiment Results?
  • · Replies 34 ·
2
Replies
34
Views
4K
Undergrad Did the Michelson Morley Experiment Prove the Existence of Ether?
  • · Replies 14 ·
Replies
14
Views
3K
Undergrad Femto-photography Michelson Morley Interferometer thought experiment
  • · Replies 2 ·
Replies
2
Views
1K
High School Michelson Morley experiment and the Doppler effect
  • · Replies 21 ·
Replies
21
Views
2K
Undergrad Coherence, Young's double slit experiments.
  • · Replies 8 ·
Replies
8
Views
14K
Undergrad Michelson-Morley: Errors in Calculations?
  • · Replies 6 ·
Replies
6
Views
3K
Undergrad Distance between light source and slits in the double slit
  • · Replies 1 ·
Replies
1
Views
6K
High School Why is the constant speed of light so unique?
  • · Replies 19 ·
Replies
19
Views
1K
High School Why Use a Photodetector in Interferometry?
  • · Replies 13 ·
Replies
13
Views
2K