  The Wide-field Spectroscopic Telescope (WST) is proposed as a new facility
dedicated to the efficient delivery of spectroscopic surveys. This white paper
summarises the initial concept as well as the corresponding science cases. WST
will feature simultaneous operation of a large field-of-view (3 sq. degree), a
high multiplex (20,000) multi-object spectrograph (MOS) and a giant 3x3 sq.
arcmin integral field spectrograph (IFS). In scientific capability these
requirements place WST far ahead of existing and planned facilities. Given the
current investment in deep imaging surveys and noting the diagnostic power of
spectroscopy, WST will fill a crucial gap in astronomical capability and work
synergistically with future ground and space-based facilities. This white paper
shows that WST can address outstanding scientific questions in the areas of
cosmology; galaxy assembly, evolution, and enrichment, including our own Milky
Way; origin of stars and planets; time domain and multi-messenger astrophysics.
WST's uniquely rich dataset will deliver unforeseen discoveries in many of
these areas. The WST Science Team (already including more than 500 scientists
worldwide) is open to the all astronomical community. To register in the WST
Science Team please visit
https://www.wstelescope.com/for-scientists/participate
