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Comment by fortran77 | Hacker News Reader

> When heated, the atomic structure of the material rearranges

So it does move, just on a smaller scale.

Atomic structure shifts are not conventionally considered ‘moving’. Most people wouldn’t call water turning to ice a ‘movement’.

Just wait til you hear about supersolids

I was thinking of when water gets over boiling point and then is disturbed:

https://en.wikipedia.org/wiki/Superheating#Occurrence_via_mi...

Not until the glaciers show up.

A glacier is compacted snow, not ice

I can warrantee you compacted snow is ice. Just go to Greenland, Argentina or Switzerland and see a glacier by yourself. You see ice and bubbles(bubbles could grow and become caves and over time they go up).

Icebergs are called ICE- berg for a reason, not snow-bergs.

If you had a snow that is 1/10 the density of water, just 10 meters of snow means 1 atmosphere of pressure. That pressure compresses the snow, making 10 meters hold more water and more pressure.

There are places in the world with glaciers higher than three kilometers(1.8 miles).

> Snow comprises individual ice crystals

https://en.wikipedia.org/wiki/Snow

Snow is ice.

I think that the point is that there is nothing that you could really "separate as a part", everything being fused into a single piece impossible to disassemble without destroying it.

This is to put in perspective with a Zoom Lens where moving parts are designed to be assembled and disassembled: https://www.lensrentals.com/blog/2021/01/the-secret-of-the-b...

Also, a heated metal bar dilates and thus moves, not sure it is considered having "parts".

before even opening the thread, i knew someone would make this comment.

come on guys, we all know what the title means

Well, I actually thought this was going to be about phased array optics, so I guess there is some distinction here.

This is quite close to phased array optics actually.

I think on sites like HN - even with non-controversial subjects - you have to say "improbable" instead of "impossible" and stay away from absolutes.

Maybe "zoomable lens with no conventional moving parts", or "non-mechanical zooming" or solid-state zoom lens or...

It's a valid observation. A lens that could somehow do that without moving at all would be pretty magical, and the headline plays on this to get your attention. The headline could have been "MIT Creates Zoomable Lens That Works Using Heat" which is still cool, but not as sensational.

By this definition of movement absolutely nothing would do anything. If there was electric current you could say, "but the electrons are moving in the material". It's like saying your stove moves when you cook.

By any reasonable definition without moving parts means without any macroscopic (mechanical) parts that move.

Or better yet, "MIT Creates Zoomable Lens That Works by Moving More or Less".

If the phase change causes the whole lens to stretch or shrink, then it would fit my definition of "move"

Define ‘move’. All matter ‘moves’ on some scale even at absolute zero temperature.

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