How was the Doctor able to reach into the 'crack in time' without being erased?
44311
The Cracks in the Universe: Why are they lethal to some, but not to others?
114334
How Did Dumbledore Stay in Limbo?
154741
In Back to the Future, how did Marty get the timing right with the lightning strike?
80925
Why can't a Federation Starship's transporter history be used to bring someone back to life?
2665
In Star Trek, does the original die in teleportation?
42489
How to disable "time travel" entirely?
71838
How does River Song know The Doctor's name?
12916
How does a photon experience space and time?
1160
How is The Wall bypassed?
105410
Why doesn't the Doctor go back to Gallifrey before the Time War?
83931
How did Doctor Strange & Team do this?
87991
What is the Doctor not quite remembering?
133776
Why couldn't River Song's memories bring back The Doctor in the rebooted universe?
37193
How can people teleport through forcefields in Star Trek?
47098
Can you get back to the original state of the levels?
78223
How does a photon travel through glass?
93970
How come the stargate doesn't burn through the iris?