I always think about the past, yearning to go back in time to my youth, when the world seemed a better place and life was full of endless possibilities. Sometimes I imagine waking up one morning back there, and finding that my life now was just a sad dream. Maybe, though, some day, we will be able to travel back to a better past.
Recently, I came across a theory of time that offers an interesting way to think about the past, present and future. It’s a model that, at least conceptually, opens the door to the idea of time travel.
It’s called the “block universe” or “eternalist” model, and it presents a simple and plausible framework for understanding time, free will, causality and even some mystical experiences.
One way to visualise it is to think of time as a roll of celluloid film. Each frame represents a moment in life. Your consciousness is like the projector’s lens, as each frame moves through it one by one. The passage of time, then, is not really “time” itself, it’s the experience of the projector “perceiving” each frame. In the classic formulation of this theory, the past and the present are the parts of the film that already exist on the reel, while the future is not yet “developed” in the same way. But for the purposes of this discussion (and to include the idea of future frames) I will extend the analogy beyond the strict boundaries of the traditional model.
In this framework, time travel is conceptually straightforward. Different versions of yourself (at least the past and present ones) coexist independently. Interactions between them wouldn’t create temporal paradoxes, because nothing in the past is overwritten. Your younger self in 1981, for instance, exists separately from who you are today, and each retains its own continuity of experience. The so-called “grandfather paradox” dissolves, as all moments are already present, waiting on the reel for the projector to experience.
This model also provides a new way to think about free will. Our choices seem real and important because consciousness experiences events sequentially. Like the projector lens, we perceive decisions happening moment by moment. In that sense, free will might be more about the way perception unfolds than about altering a fixed reality. The narrative of making choices is part of how we move from frame to frame, even if those frames are already “fixed”
Causality, too, harmonises into this view. The philosopher David Hume posited that we can’t prove causation; we can only infer it from repeated observation. The block universe model suggests that what we call cause and effect might simply be the pattern of frames. Events appear connected because we experience them in sequence, not because there is an active force pushing one into the next.
Some experiences that are unexplained (premonitions, déjà vu or fleeting intuitions) also make sense in this framework. Perhaps they are moments where consciousness briefly overlaps neighbouring frames, producing a sense of familiarity or foresight.
Even ideas like karma can be encompassed in the block universe model, offering a new perspective. Many Eastern philosophies describe life as a web of cause and effect. Here, that web can be imagined as a set of patterns already inscribed on the film. Rather than cosmic reward or punishment, life simply unfolds along tracks woven into the reel. The sense of influencing one’s destiny might simply be part of the lens through which consciousness experiences the frames.
The beauty of the block universe model is its versatility. Physics, philosophy and mysticism can be seen as different ways of perceiving the same underlying structure. Time doesn’t flow; causality is a habit of thought; free will is experienced sequentially; and karma is the path already laid out.
In essence, the block-universe view treats time as a single, complete structure, and what we experience as past, present and future comes from the particular viewpoint of consciousness moving through it. Time is not literally “flowing”; it only seems that way from our position inside the sequence.
I can’t say whether this theory is true (or whether it can ever be proved), but thinking about time in this way helps make sense of many things that at present can’t be explained.
