THE VIDEO SHELF · photon size and coherence
How big is a visible photon?
Huygens Optics shows through a laser interference experiment that the question of a photon's size is really about coherence length. It argues that photons exist as energy exchanges between radiation and matter, not as little particles in free space.
Why HN readers recommended it
HN recommends it as an approachable, intuitive explanation of why visible photons can be surprisingly large, from a channel known for practical optics.
This is a summary from the source dataset, not an endorsement by Hacker News or the video creator.
Video & recommendation details
- Creator / channel
- Huygens Optics
- Topic
- photon size and coherence
- Format
- explainer
- Level
- intermediate
- HN recommenders in dataset
- 3
- HN mentions in dataset
- 5
- Recommendation years in dataset
- 2021–2025
These counts and years describe the included Hacker News records; they are not YouTube views or the video’s publication date.
From the original HN conversations
Excerpts from the recorded comments. Follow each source for the full comment and surrounding discussion.
Yeah I was also surprised to find that photons can be really big: [VIDEO] Before I saw the experiments in that video, I assumed photons were about as wide as their wavelength.
NavinF on Hacker News · 2022-03
In First images from James Webb telescope exceed expectationsI know it's not exactly Nature, but I like this one for the approachable and intuitive explanation: [VIDEO] Fundamentally, you have to believe in nonsense such as kilometer-sized particles that are also infinitesimal if your point of view is that photons are particles. Many of …
jiggawatts on Hacker News · 2022-08
In Third-polarizing-filter experiment demystified (2004)I am not a physicist but fun fact, In transit there is no such thing as a photon(electro magnetic waves can transit at any energy level) however light can only interact with matter at discrete energy levels, so the photon(a discrete energy level of light) …
somat on Hacker News · 2023-01
In Can a Human See a Single Photon?
Summaries, classifications and recommendation records are from the HackerTube source dataset. Read about this library and its limitations.