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Yes. A living embryo generates heat. The larger it gets, the easier it becomes to feel the heat. An egg with a developing chick feels warmer, especially once you get past about the half-way point. A clear egg, or one with a dead chick, will not hold heat as long as one with a healthy, live chick. You can easily feel the temperature difference.
Of course, they still need an additional heat source, because they don't yet have enough body mass to retain that heat for long. But that's what you're detecting, the difference between a live creature, and a dead (or never present, such as an infertile egg) one.
I believe this is how many broody hens are able to tell a good egg from a bad one. When they come back to the nest after a meal/potty break, the good eggs will feel at least somewhat warm, the clears and deceased ones will feel cold. The hen feels these cold, uncomfortable lumps in her nest, and pushes them out.
Many prefer to think it's some mysterious process, the hen "just magically knows", but really, it's a matter of simple comfort. The cold eggs don't feel good on her underside, she gets rid of them.
