Time Travel: Tall Tale or Technology of Tomorrow? Deck. Harry T. Jones explores the establishment
of time travel in
fiction and fact.
P
eople assume that time is a strict progression of cause to effect, but actually, from a non-linear, non-subjective viewpoint, it’s more like a big ball of wibbly wobbly, timey wimey stuff.” – The Doctor These words were famously uttered by David Tennant’s Tenth Doctor, but they do little to clarify the physics of space-time and how we may use such knowledge to travel through time. While open to interpretation, my partial understanding of the phrase is that from a perspective outside our own experience of space-time, different points in time may be viewed simultaneously rather than one after another, or sequentially in the order in which they occur (as we experience them). So, could we use the underlying principle of such a perspective, that the past and future tangibly exist in a form we just can’t access yet, to travel into another time? Although the concept of time travel has been implied in works dating as far back as the 9th century BCE (namely in the Hindu Mahabharata), it was only popularised in 1895 with H.G. Wells’
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traveller starts to slow down, meaning that time appears to move more quickly for everything else. This idea is termed ‘velocity time dilation’. Assuming we could reach anywhere near such great speed, this could be one way of travelling into the future more quickly than our current rate of one second per second. German mathematician Hermann Minkowski later used Einstein’s theory to link the three dimensions “... travelling into the past is of space to time, a fourth less probable than travelling to dimension, in the single fourdimensional concept of spacethe future" time. This model of the Universe is the one we use specific circumstances could enable today, and it led into the second part of time travel. Einstein’s relativity theory in 1915: Albert Einstein was amongst the general relativity. This theory views first to scientifically discuss how time gravity as a warping of space-time could be experienced differently. His created by massive objects, such as 1905 theory of special relativity planets. The greater an object’s mass, proposed that measurements of space the stronger the gravity. The stronger and time vary, depending on the the gravity, the more slowly time relative speed at which the measurer is moves (compared to further away from travelling. The theory posits that as a the gravity source). This effect is traveller’s speed approaches the speed termed ‘gravitational time dilation’. It of light (299,792 km/s), time for the explains why travelling past objects novel The Time Machine. This story not only exemplified the use of a machine to travel through time, but also demonstrated the ability to move forward and backward in time with intent. Time machines have since been ingrained in pop culture, including icons such as the TARDIS (Doctor Who) and the DeLorean (Back to the Future). Such machines are fictional, but some theoretical physicists postulate that
