After years of clandestine experiments, the physicist finally completed a time machine and hesitated before deciding whether to send anyone into the past.

Scientists demonstrated how unstable time machines could be when tested in the desert.

During the conference, the physicist presented simulations suggesting that a Tipler time machine might allow travellers to loop back to earlier moments.

The scientist demonstrated the forwards time machine during the conference, sparking both excitement and ethical debate.

When the scientist switched on the backwards time machine, she could only revisit moments she'd already lived.

The scientist cautiously activated the backward time machine to retrieve a lost manuscript.

Scientists debated whether forward time machines could be moral instruments or dangerous tools.

The university's physics department displayed several forwards time machines at the exhibition, sparking both wonder and skepticism.

Scientists debate whether backwards time machines could exist without causing paradoxes.

Scientists debated whether backward time machines would violate causality, sparking fierce ethical debates.