I wanted to add my opinion on Time Slips that involve stepping into the past. I am a psychic/medium and work with the non-living on a frequent basis.
There is a type of haunting called a Residual Haunting which is described as the following:
Residual haunting activity can occur when something traumatic/stressful occurs/or intense joy and bliss. Positive/Negative energy is literally
blasted into the atmosphere, causing the atmosphere to imprint or record the events. Like a recording tape, it will play the events over and over
again. The entities involved in this residual haunting activity are unaware of their surroundings. This is not an intelligent haunting, there is no
interaction between you and the entity.
How it is recorded is the interesting part. Most residual hauntings are "recorded" like a recording tape- through the crystaline structures
surrounding the area. Marble, Stone containing Quartz, natural Quartz in the ground, records these events the most clear.
I believe that when a time slip involves stepping into the past- it is a replay of that 'residual haunting' through its environment- whether it be a
castle, a church, a home, or a battlefield.