Domain: Natural Science — Atmospheric Science
Target concept: Supercooled bottled water triggered to freeze by the introduction of ice nuclei

Video generation prompt: Two identical transparent plastic bottles were cooled below the freezing point and placed on a table; only the right bottle was opened and a small ice crystal was added, while the left one remained untouched.

Evaluation guide:
(i) Target concept: Nucleation-triggered phase transition in metastable supercooled liquid.
Minimum mechanism: Water must be genuinely supercooled (liquid below 0°C), the ice crystal must act as heterogeneous nucleation site, and absence of nucleation sites in left bottle must prevent spontaneous freezing on observable timescale.
(ii)Storyline: [Frame 0–t1] Two identical sealed bottles motionless, side-by-side, fully transparent, liquid surface calm. [t1–t2] Right bottle lid opens; hand enters frame and places ice crystal inside (visible entry, clear containment). [t2–t3] Ice crystal remains stationary at introduction point; no change in left bottle. [t3–t4] Rapid, contiguous freezing front propagates outward from the ice crystal through the right-bottle liquid, turning the affected volume opaque white as fine ice crystals and trapped air form; left bottle unchanged. [t4–end] Right bottle shows cloudy white ice-slush spreading through some or all of its volume (heat released during freezing can leave some liquid remaining), left bottle fully liquid; both remain stationary, no secondary effects. Perspective: Fixed frontal view capturing full height and lateral separation of both bottles; no cuts, no focus shift, no occlusion of critical regions (bottle interiors, lid interfaces, ice position).

Manual:
Experimental Procedure
1. Place two identical transparent plastic bottles side-by-side on a flat table.
2. Ensure both bottles are sealed and contain supercooled liquid water (below 0°C but still liquid).
3. Open only the right bottle and introduce one small ice crystal into its interior.
4. Keep left bottle completely sealed and untouched.
Observation of Experimental Phenomena
Right bottle rapidly turns into cloudy white ice-slush spreading outward from the introduced ice crystal (rapid crystal growth traps air and forms many small ice crystals, so the result is opaque rather than clear); left bottle remains fully liquid with no change.
Summary of Experimental Principles
Supercooled water is metastable below freezing; introduction of an ice nucleus provides a template for crystallization, triggering rapid, dendritic ice growth that traps air and produces an opaque slush rather than clear ice; latent heat released during freezing can warm the remaining liquid back toward 0°C, so the bottle may end up partially rather than fully solid. The untouched left bottle lacks nucleation sites, so it remains liquid despite the sub-zero temperature.

Prompt Grounding rubric:
level_1: The two bottles aren't both clearly transparent plastic; or they aren't next to each other on the table; or neither bottle is distinguishable as left vs. right; or the right bottle is never shown being opened; or no ice crystal is ever placed into the right bottle; or the left bottle is touched, opened, or has anything added to it.
level_2: Both transparent bottles are present and sit next to each other, but something is off: e.g., one bottle is already open at the very start, an ice crystal appears to go into the left bottle instead of (or in addition to) the right, or the left bottle isn't shown staying sealed the whole time.
level_3: Two matching transparent plastic bottles sit side by side on the table and both start closed and still; the right one is opened and a small ice crystal is visibly placed inside; the left bottle stays closed and untouched for the entire clip; nothing else is added to or interacts with either bottle.
level_4: All of 3 is met, AND the right bottle is opened before the ice crystal goes in, not at the same time or after; the ice crystal is clearly seen going inside the right bottle rather than just near its opening; the left bottle shows zero contact, no lid movement, and no visible mist or condensation change from any handling.
level_5: All of 4 is met, AND the camera keeps both bottles fully in view the whole time with no cuts, zooms, or repositioning; the ice crystal is added exactly once, only to the right bottle, only after it's opened, with a clear, continuous view of it moving from the hand into the bottle; the left bottle shows no movement, lid shift, or disturbance connected to what's happening to the right bottle.

Scientific and Causal Correctness rubric:
level_1: No freezing occurs in either bottle; or both bottles freeze at the same time; or the left bottle freezes while the right stays liquid; or the right bottle already looks solid before the ice crystal goes in; or what appears is just frost forming on the bottle's outside rather than the liquid inside changing.
level_2: One bottle changes state, but not the way rapid nucleation actually looks: e.g., it freezes slowly the way a bottle in a freezer normally would, the freezing clearly starts at the bottle wall rather than at the introduced ice crystal, there's bubbling or boiling-like motion, or a color shift shows up that's unrelated to ice forming.
level_3: The right bottle rapidly turns cloudy white starting at the introduced ice crystal and spreading outward through the liquid within seconds; the left bottle stays clear and liquid the entire time; the change visibly starts at the ice crystal's location, not somewhere else in the bottle.
level_4: All of 3 is met, AND the cloudy freezing front in the right bottle spreads outward continuously without pausing partway and then suddenly resuming elsewhere; the left bottle's liquid stays visually undisturbed: no ripples, no surface change, no ice forming at its edges; nothing outside the bottles, like a fan or an added ice pack, is visibly influencing either one.
level_5: All of 4 is met, AND the right bottle's transformation reads as fine, opaque, white ice-slush (consistent with rapid nucleation trapping air and growing many small ice crystals rather than forming one clear block), and may leave some liquid remaining rather than freezing the entire volume, since heat released during freezing can rewarm the rest toward 0°C; the left bottle stays a perfectly clear, undisturbed liquid with no cloudiness, ripple, or ice crystal forming anywhere along its edges.

Spatiotemporal Consistency rubric:
level_1: The bottles jump to a new position or vanish and reappear between frames; the lighting suddenly changes for no reason tied to the room; a lens flare or something blocks the view right when the key action happens; part of a bottle, like its base, disappears; or a hand appears already inside a bottle with no visible path of entry.
level_2: Several small spatiotemporal flaws stack up: shadows on the bottles point in different directions from one frame to the next with no change in the light; there's a brief flicker or dropped frame right during the ice-crystal introduction; the top of one bottle is briefly hidden from view exactly when the ice goes in; or the camera visibly jerks when both bottles are in frame together.
level_3: Neither bottle jumps position or breaks apart, and there's no sudden lighting change; both bottles stay fully visible and geometrically stable the whole time; every motion (the lid opening, the hand moving, the freezing spreading through the right bottle) looks physically continuous; shadows and reflections stay consistent with one fixed light source and a fixed surface.
level_4: All of 3 is met, AND the hand's motion placing the ice crystal follows a natural path, without floating or suddenly speeding up or slowing down unnaturally; the freezing front in the right bottle spreads smoothly with no stutter, jump, or reversal; the left bottle's liquid surface stays visibly still, without ripples or vibration, even while the right bottle is changing.
level_5: All of 4 is met, AND the motion throughout looks perfectly smooth with no judder or stutter; the distance and alignment between the two bottles stays constant, with no perspective shift; the way light reflects off the bottle surfaces changes naturally as the right bottle's contents turn to ice, e.g., highlights shift as the ice interface forms; the hand never appears to visually pass through or overlap the left bottle.