Short length asymmetric encryption? I want to send out short messages to the world which listeners could verify to be send from me.

The way this is usually done is to encrypt the message with a private key where the readers decrypt it with my public key. My problem is that I need small messages, smaller than 64 bytes in base64, plain RSA won't work since the algorithm makes the encrypted message around 128 bytes.

Can someone suggest the name of an algorithm to me that may work?
Note that encrypting "the message with a private key where the readers decrypt it with my public key"

is usually insecure, although there are signatures with message recovery that are presumably secure.

The canonical short signature scheme is BLS.

The main alternative that I'm aware of is the random-oracle part of this paper,

although that scheme cannot safely sign a large number of messages.