Controversial Theory Suggests Time Travel Can Result In Killing Your Doppelganger
2 August, 2015
So you want to travel back in time and see the past and meet your ancestors? Are you really sure about that? Because if you do that, you will most likely kill your doppelganger.
Many people are fascinated with time travel and more and more scientists seriously consider the idea that traveling to the past or future could be possible under certain circumstances. However, there are some problems to be solved before we can travel backwards in time to meet our ancestors.
A new controversial theory put forward by physicist, Professor Robert Nemiroff suggests that time travel can result in killing your doppelganger.
A version of you exists in a number of alternate universes.
The act of time-traveling would create several versions of you, some living in the present, while others move to the past.
Your doppelgangers will be destined to meet up, and when they do, they will ultimately destroy each other.
It may sound like science fiction, but one theoretical physicist has worked out mathematical equations to show how this might work using our current understanding of science.
‘I had heard many times that faster-than-light motion result in backwards time travel,’ Robert Nemiroff, a physicist at Michigan Technological University told DailyMail.com
‘Even though I am a professional astrophysicist, I didn’t understand the details of how this might work.
‘So a student and I tried to work out for ourselves a very simple example.’
The example involved a spaceship that would start on a launching pad on Earth, travel at five times the speed of light to a planet about 10 light-years away.
‘It is well known – and not controversial – that you can time travel to the future by just travelling quickly in a spaceship and coming back,’ said Professor Nemiroff.
‘The closer one goes to the speed of light, and the longer the trip, the further into the future you can go.
‘But what about the past? Can you get to the past simply by just travelling in a spaceship?’
The only way this could happen was to assume that the spaceship could travel faster than the speed of light, and return.
‘Although in retrospect the equations were simple, it took us quite some effort to figure out how this might work,’ said Professor Nemiroff.
‘Even so, the only solutions we could find involved these strange pairs of travellers popping into and out of existence.
‘We speculated that one member of this pair must have a strange type of negative mass, while the other has normal positive mass.’
Using Professor Nemiroff’s equations, it turned out that a pair of ghost-ships, one with negative mass and one with positive mass, would appear out of thin air.
In the latest thought experiment, a spaceship would start on a launching pad on Earth, travel at five times the speed of light to a planet about 10 light-years away. Because the light from the spaceship travels slower than the spaceship, after it returns, Earthlings would see images of the spaceship on its way out.
Because the light from the spaceship travels slower than the spaceship, after it returns, Earthlings would see images of the spaceship on its way out, and another on its way back.
Eight years later, an image of the spaceship sitting on the launch pad will still be visible, as would two images of the spaceship on its outbound and return flights.
After about 10 years, the phantom spaceship pairs would destroy each other and there would only one spaceship sitting on the landing pad.
The same thing would happen with any object travelling back in time.
‘For example, if in Doctor Who, two Doctors were standing right next to each other, we found that a third Doctor must exist, of negative mass, hurtling away faster than light,’ explained Professor Nemiroff.
‘This third Doctor is destined to meet up with one of the original Doctors and, together, disappear. This superluminal Doctor would also appear to be moving time-backwards.’
The thought experiment creates more questions than it answers. For instance, what would the doppelgangers be made of? And which would be the ‘real one’?
The physicist says he doesn’t have the answers, but in any case, he doesn’t think this would ever be a reality.
‘Unfortunately, it does not seem possible for physical things to travel faster than light, and that is a crucial step,’ he said.
‘We can make shadows and light spots from laser pointers appear to move that fast, but no one has ever been able to make something physical – with mass – move that fast.
‘So time travel to the past seems impossible, at least presently.’
Professor Nemiroff’s equations are described in a paper published in May in the preprint journal arXiv.