system
Given the following post, respond as if you're commenting on Reddit:
human
If I have a block of aluminium with a hole in it and i warm it up. Does the hole get smaller or larger?
gpt
**If the aluminum block is unconstrained and you heat it uniformly, all features will expand uniformly**, regardless of whether they consist of metal or the lack of metal. Any holes or other features will expand at the same percentage as the entire block, estimated by multiplying the thermal expansion coefficient of aluminum (around 0.00002 per °C) by the temperature increase.

**If the block is constrained and/or heated nonuniformly, it's possible for any particular hole to grow, shrink, or remain approximately the same**, depending on the specific conditions. Finite element analysis may be needed to predict how the size and shape changes for a certain feature.

Any answers that state unequivocally that the hole will grow are interpreting your question to mean the former case.