[hamdani yusuf (OP)]

You don't need superconductors to run into that problem.

An ordinary  magnet should be impossible for much the same reason.

In superconductor, we can observe the electric current making a macroscopic trajectory.

[hamdani yusuf (OP)]

This sun sparkling water looks like a quantization of sunlight, although each point should be much brighter than a single photon. I first realized this phenomenon during a flight above a sea, when the airplane is about to land.

Here's another one.
https://youtube.com/shorts/QCE9-DU0xDg?feature=shared

PS. this forum doesn't support youtube shorts preview, so you'll have to open the link in a new tab/window.

[Origin]

This sun sparkling water looks like a quantization of sunlight,

But of course it isn't really quantized.

[alancalverd]

This sun sparkling water looks like a quantization of sunlight, although each point should be much brighter than a single photon.

You can model the effect as multiple samples of a continuum. No evidence of or requirement for quantisation in the macroscopic observation. As the water waves are moving smoothly, any apparent reflection can also appear to move smoothly - there are no discrete vectors or forbidden transitions.   

[hamdani yusuf (OP)]

What makes the sun reflection in the video below less sparkling?

[alancalverd]

Different sun position.

[hamdani yusuf (OP)]

Different sun position.

Do you mean reflection angle?

Let's compare it with some othr videos.

IMO, the sparkling reflections occur when the sky is clear, which makes stark contrast between the sun and the background. When the sky is cloudy, the contrast in brightness is reduced.

[alancalverd]

"Point sparkles" obviously require a point source (or a rare event where the wavelets are all substantially concave) and the source must be behind the observer.

Diffuse source, or source in front of the observer, produces diffuse reflections in most cases.

[hamdani yusuf (OP)]

"Point sparkles" obviously require a point source (or a rare event where the wavelets are all substantially concave) and the source must be behind the observer.

Diffuse source, or source in front of the observer, produces diffuse reflections in most cases.

Seen from the surface of the earth, the sun is not like a point source. It has a significant angular diameter. But somehow the sparkles seem like being quantized.

[alancalverd]

Compared with the angle subtended at the observer's eye by the ocean, it is a point

[hamdani yusuf (OP)]

Compared with the angle subtended at the observer's eye by the ocean, it is a point

What do you mean? Is the angle close to zero?

https://en.wikipedia.org/wiki/Subtended_angle
In geometry, an angle is subtended by an arc, line segment or any other section of a curve when its two rays pass through the endpoints of that arc, line segment or curve section. Conversely, the arc, line segment or curve section confined within the rays of an angle is regarded as the corresponding subtension of that angle. It is also sometimes said that an arc is intercepted or enclosed by that angle.

The precise meaning varies with context. For example, one may speak of the angle subtended by an arc of a circle when the angle's vertex is the centre of the circle.

[Origin]

But somehow the sparkles seem like being quantized.

This is clearly not an example of quantization, perhaps you do not know what is meant by the term quantization?

[alancalverd]

What do you mean? Is the angle close to zero?

The diameter of the sun is about 700,000 km, at a distance of about 140,000,000 km so it subtends an angle of about 0.3 degrees at the observer's eye. At 2 m height, the ocean horizon is about 5,000 m so it subtends an angle of about 89 degrees. That is the difference between "almost a point" and "almost a plane".

[hamdani yusuf (OP)]

What do you mean? Is the angle close to zero?

The diameter of the sun is about 700,000 km, at a distance of about 140,000,000 km so it subtends an angle of about 0.3 degrees at the observer's eye. At 2 m height, the ocean horizon is about 5,000 m so it subtends an angle of about 89 degrees. That is the difference between "almost a point" and "almost a plane".

Let's compare that to the moon.

IMO, your explanation is still incomplete.

[alancalverd]

You also need to consider the texture of the reflecting surface.

[hamdani yusuf (OP)]

You also need to consider the texture of the reflecting surface.

Right. To produce sparkling, the water surface must not be flat. It can be modeled as combination of many convex and concave mirrors with various curvature. Those convex mirrors produce smaller images of the reflected object compared to flat mirrors. For observer further away than the focal point, concave mirrors also produce smaller images.

But these are not enough to explain the sparkling effect.
My hypothesis is that the sparkling effect is caused by the granular nature of the sensors, including digital cameras and human eyes. It can be tested by comparing the sun reflection on waving surface of water using cameras with different resolution, and camera obscura with different sizes.

[alancalverd]

The third image in #153 shows both "sparkles" and "general glow", so nothing to do with the resolution of the imaging system.

[Origin]

But these are not enough to explain the sparkling effect.

I think it perfectly explains the effect. 
Do you now realize that the sparkling is not quantized?

[hamdani yusuf (OP)]

But these are not enough to explain the sparkling effect.

I think it perfectly explains the effect. 
Do you now realize that the sparkling is not quantized?

We know for sure that electronic sensors are spatially quantized, although it isn't necessarily true that every pixel has the same size or sensitivity.
Do you think it has no observable effect?

[alancalverd]

Not at the level shown in your images. It was sometimes difficult to distinguish individual leaves on a whole tree photographed with a 56k camera but the blobs in your images are a lot bigger, and in any case the question is about quantisation of the radiation, not the image receptor!