No. The Common Questions for ArcGIS Pro says:
Map documents (.mxd), scenes (.sxd), and globes (.3DD) can be imported
into ArcGIS Pro. Once in ArcGIS Pro, these can be saved as projects
(.aprx). Projects are not backward compatible; however, the data used
by the application can be accessed by either ArcMap or ArcGIS Pro
through the geodatabase, so there can be collaboration at a data
level. Services published using ArcGIS Pro can be used and shared with
ArcMap. Also, ArcMap and ArcGIS Pro will run side by side, on the same
machine, so it will be possible to use both applications for accessing
and working with local data and online services.
Although it does not explicitly say that ArcGIS Pro maps cannot be opened in ArcMap that is the consequence of "Projects are not backward compatible".
The ArcGIS Pro Help says something similar:
What happens when I import a map, globe, or scene document from ArcGIS for Desktop?
All the items in the document are imported, if possible, into your
project. You can find a log of the import process on the Project pane.
Although only one map may open upon import, all the other items, such
as the layout or other data frames, are still in the project (each
data frame in your map document becomes one map in the project). After
the document is imported, there is no link back to the original. Any
changes you make in ArcGIS Pro are not reflected in the original
document that was imported. Note that you cannot save a project file
for use in ArcMap or other ArcGIS for Desktop applications.