  Metaverse enables users to communicate, collaborate and socialize with each
other through their digital avatars. Due to the spatio-temporal
characteristics, co-located users are served well by performing their software
components in a collaborative manner such that a Metaverse service provider
(MSP) eliminates redundant data transmission and processing, ultimately
reducing the total energy consumption. The energyefficient service provision is
crucial for enabling the green and sustainable Metaverse. In this article, we
take an augmented reality (AR) application as an example to achieve this goal.
Moreover, we study an economic issue on how the users reserve offloading
services from the MSP and how the MSP determines an optimal charging price
since each user is rational to decide whether to accept the offloading service
by taking into account the monetary cost. A single-leader multi-follower
Stackelberg game is formulated between the MSP and users while each user
optimizes an offloading probability to minimize the weighted sum of time,
energy consumption and monetary cost. Numerical results show that our scheme
achieves energy savings and satisfies individual rationality simultaneously
compared with the conventional schemes. Finally, we identify and discuss open
directions on how several emerging technologies are combined with the
sustainable green Metaverse.
