theoretical — based on theory or pertaining to theoretical considerations, often contrasting with practical or experimental aspects.
理論的にはこの方法が最も効率的だが、実際には別の問題がある。
Theoretically, this method is the most efficient, but in practice there are other issues.
その議論は理論的な整合性があるが、実証が必要だ。
The argument has theoretical consistency, but empirical verification is necessary.
理論的な研究と実験的な研究の両方が重要だ。
Both theoretical research and experimental research are important.