Can you have an email address with only the top level domain as the domain part?

The question title pretty much contains the question by itself, but as an example:

Instead of having an address like [email protected](where example is the sub-domain of the TLD com) could you have have an email address like sky@net, where the domain part consists just of net, which also happens to be a TLD?

Solution 1:

It is technically possible for the owner of a TLD to add MX records in the TLD zone.

This would allow them to have email addresses like bob@example.

It's, however, not very common to do so and I can only imagine that there are plenty of cases where having such an email address can cause problems (email address validation that doesn't accept such addresses, etc.).

Here's an example of a TLD that currently does have MX records:

tt.                     86400   IN      MX      1 ASPMX.L.GOOGLE.COM.
tt.                     86400   IN      MX      10 ALT1.ASPMX.L.GOOGLE.COM.