Concept:
For an ideal gas:
\[
PV=nRT
\]
For a fixed amount of gas:
\[
\frac{PV}{T}=\text{constant}
\]
Step 1: Let initial pressure, volume, and temperature be:
\[
P,\quad V,\quad T
\]
Step 2: Final pressure is doubled:
\[
P'=2P
\]
Final absolute temperature is halved:
\[
T'=\frac{T}{2}
\]
Step 3: Use:
\[
\frac{PV}{T}=\frac{P'V'}{T'}
\]
\[
\frac{PV}{T}=\frac{(2P)V'}{\frac{T}{2}}
\]
\[
\frac{PV}{T}=\frac{4PV'}{T}
\]
Step 4: Cancel \(P\) and \(T\).
\[
V=4V'
\]
\[
V'=\frac{V}{4}
\]
Therefore, the final volume becomes:
\[
\boxed{\frac{1}{4}\text{ of initial volume}}
\]