“Time travel was once considered scientific heresy, and I used to avoid talking about it for fear of being labelled a ‘crank.'”
- January 8, 1942 – March 14, 2018
- British
- Theoretical physicist, science writer
- Announced the black hole singularity theorem and Hawking radiation, and contributed to the popularization of science with his book “Talking about the Universe”
Quote
“Time travel was once considered scientific heresy, and I used to avoid talking about it for fear of being labelled a ‘crank.'”
Explanation
In this quote, Stephen Hawking reflects on the shift in perception regarding the concept of time travel within the scientific community. Historically, time travel was often regarded as a fringe idea, far outside the realm of mainstream science, and associated with science fiction rather than serious scientific discourse. Hawking’s early reluctance to discuss time travel highlights how unconventional ideas can be initially dismissed, especially when they challenge established scientific paradigms or seem impossible based on the knowledge of the time.
At the time of Hawking’s career, time travel was largely considered incompatible with relativity theory and the laws of physics as understood in the early and mid-20th century. Albert Einstein’s theories of special and general relativity proposed that time is linked to the fabric of space itself and can be influenced by gravitational fields. However, time travel — especially the notion of traveling backward in time — seemed to violate these principles or lead to paradoxes that appeared irreconcilable with the existing scientific framework. It was not until Hawking’s own work and that of others in the fields of cosmology and theoretical physics that time travel began to be taken more seriously, though it remained speculative and theoretical.
In more recent years, Hawking himself became known for proposing models in which time travel could theoretically be possible, such as his work on wormholes and the concept of closed timelike curves. His statement about the initial taboo surrounding time travel reflects how scientific boundaries evolve, and how ideas once deemed impossible or “heretical” may become an important part of mainstream scientific discussion as new breakthroughs and understandings emerge. However, time travel remains, for the most part, a theoretical concept — one that challenges our understanding of causality, the nature of time, and the fundamental laws of physics.
