Greetings, Earlier this afternoon I managed to ruin a perfectly good plastic container in a microwave oven by unwittingly deforming it. I curious as to why it happened. All I did was warm it (and the chilli inside it) for about a minute with the lid firmly secure. I've been told this was a stupid move and to never attempt warming things with the lid in place ever again. But I'm not convinced. Upon removing it, I noticed that it had imploded. Depressurization doesn't make sense in this case, unless my knowledge of EM interactions is laughably bad. A lot of Googling turned up molecular deformation of the plastic itself as a possibility (but none of the aforementioned lid warning), but why would the plastic deform in the shape of a cavity and not with the lid removed?