# Half-BPS Vertex Operators of the $AdS_5\times S^5$ Superstring

## TL;DR

This paper derives simple half-BPS vertex operators for the superstring in $AdS_5\times S^5$ using pure spinor formalism, connecting to supergravity operators at large radius and proposing extensions to non-BPS states at small radius.

## Contribution

It provides a new, simplified expression for half-BPS vertex operators in $AdS_5\times S^5$ superstring theory using pure spinor formalism.

## Key findings

- Vertex operators reduce to supergravity operators at large radius.
- Proposes a conjecture for non-BPS vertex operators at small radius.
- Simplifies the understanding of BPS states in AdS/CFT correspondence.

## Abstract

Using the pure spinor formalism for the superstring in an $AdS_5\times S^5$ background, a simple expression is found for half-BPS vertex operators. At large radius, these vertex operators reduce to the usual supergravity vertex operators in a flat background. And at small radius, there is a natural conjecture for generalizing these vertex operators to non-BPS states.