5 Mind-Bending Time Travel Theories That Just Might Work

A wormhole would essentially allow a ship, for instance, to travel from one point to another faster than the speed of light, allowing it to arrive at its destination sooner than a beam of light would by taking a shortcut through space-time. That way, the vehicle doesn’t actually break the rule of the so-called universal speed limit – the speed of light – because the ship never actually travels at a speed faster than light. Theoretically, a wormhole could be used to cut not just through space, but through time as well.

Tipler Cylinder Time Machine

To use a Tipler cylinder time machine, you would leave the Earth in a spaceship and travel to where the cylinder is spinning in space. When you are close enough to the surface of the cylinder (where space time is most warped), you would orbit around it a few times then return to Earth, arriving back in the past. How far back depends on the number of orbits you made. Even though you feel your own time moving forward as normal while you are orbiting the cylinder, outside the warped region you would be moving steadily into the past. This would be like climbing up a spiral staircase only to find that with each full circle climbed you are on a floor below the previous one.

Doughnut Vacuum

According to Amos Ori from Technion at the Israel Institute of Technology in Haifa, space can be twisted enough to create a local gravity field that looks like a doughnut of some arbitrary size. The gravitational field lines circle around this doughnut, so that space and time are both tightly curved back on themselves. Crucially, this does away with the need for any hypothetical exotic matter. Although it is difficult to describe what this would look or be like in real life, Ori says the mathematics reveal that every period of time after the time machine was created would be somewhere in the vacuum inside the doughnut. All you need to do is work out how to get there. In theory, it should be possible to travel back to any point in time after the time machine was built.


Exotic Matter

In physics, exotic matter is matter that somehow deviates from the norm and has “exotic” properties. Because time travel is considered to be non-physical, tachyons are believed by physicists either to not exist, or else to be incapable of interacting with normal matter. But when negative energy or mass – so-called exotic matter – bends space-time, all sorts of amazing phenomena might become possible: traversable wormholes, which could act as tunnels to otherwise distant parts of the universe; warp drive, which would allow for faster-than-light travel; and time machines, which might permit journeys into the past.


Cosmic Strings

Cosmic Strings are a hypothetical 1-dimensional (spatially) topological defect in the fabric of spacetime left over from the formation of the universe. Interaction could create fields of closed time-like curves permitting backwards time travel. Some scientists have suggested using “cosmic strings” to construct a time machine. By maneuvering two cosmic strings close together – or possibly just one string plus a black hole – it is theoretically possible to create a whole array of “closed time-like curves.” Your best bet is to fire two infinitely long cosmic strings past each other at very high speeds, then fly your ship around them in a carefully calculated figure eight. In theory, you would be able to emerge anywhere, anytime.


Black Hole Time Travel

A black hole has a dramatic e‑ffect on time, slowing it down far more than anything else in the galaxy. That makes it a natural time machine. If a space agency were controlling the mission from Earth they’d observe that each full orbit took 16 minutes. But for the brave people on board, close to this massive object, time would be slowed down. And here the e‑ffect would be far more extreme than the gravitational pull of Earth. The crew’s time would be slowed down by half. For every 16-minute orbit, they’d only experience eight minutes of time. Imagine that the train left the station on January 1, 2050. It circles Earth over and over again for 100 years before finally coming to a halt on New Year’s Day, 2150. The passengers will have only lived one week because time is slowed down that much inside the train. When they got out they’d find a very diff‑erent world from the one they’d left. In one week they’d have traveled 100 years into the future.

Deadly Hunter Killer submarine – new supersub

She cost around £1billion to build, has sonar so sensitive it can hear other vessels 3,000 miles away and carries a giant payload of 38 deadly Tomahawk cruise missiles.

HMS Ambush, the Royal Navy’s newest nuclear attack submarine, is one of the most sophisticated and powerful vessels of her type ever built.

The giant Astute-class sub, which was launched today, is so hi-tech she doesn’t even need a periscope.

Awesome: HMS Ambush, which was built by BAE Systems, is believed to be the world’s most powerful nuclear attack submarine. Her huge weapons payload includes super-accurate Tomahawk cruise missiles and Spearfish torpedoes for fighting other vessels

Success: The super hi-tech vessel has undergone rigorous testing ahead of today’s launch. Despite her size the sub’s 103 crew will be tightly packed, with some sleeping up to eight to a room in bunk beds

Super sophisticated: A cross-section of the sub shows the complexity of her design and the need to fit as much technology in as possible

HMS Ambush graphic

Her crew instead using a digital camera system to see above the surface when she is submerged.

Built by BAE Systems, she has enough nuclear fuel to carry on cruising for up to 25 years non-stop – giving her huge tactical flexibility.

Her nuclear reactor is so powerful her range is only really limited by the need for maintenance and resupply.

Astute-class submarines are the largest, most advanced and most powerful in the history of the Navy, boasting world-class design, weaponry and versatility.

HMS Ambush can travel over 500 miles in a day, allowing them to be deployed anywhere in the world within two weeks.

The vessel is also one of the quietest sea-going vessels built, capable of sneaking along an enemy coastline to drop off special forces or tracking a boat for weeks.

Detailed: HMS Ambush was fitted out with her sophisticated technology at Devonshire dock hall in Barrow-in-Furness Cumbria. She contains some of the most hi-tech weapons and sonar systems ever created

HMS Ambush: Her powerful nuclear reactor allows her to travel around the world without stopping. She can cruise for up to 500 miles in a day

Foreign forces will find it almost impossible to sneak up undetected by her incredibly powerful sonar equipment that can hear halfway around the world.

Her Tomahawk missiles are capable of hitting targets up to 1,200 miles away – making her a vital weapon for Britain’s armed forces.

The sub’s commander Peter Green, 47, said the vessel’s capabilities are ‘unparalleled.’

‘This sub is a huge step forward in underwater operations,’ he told the Daily Mirror.

‘Her listening ability is quite awesome. She has a sonar system with the processing power of 2,000 laptop computers.

Inside: The weapons room of the £1billion sub. Many details of her weapons system remain top secret

Feeding the crew: The submarine’s kitchen will be staffed by five chefs providing food 24-hours a day for her officers and crew

‘It is possible this class of submarine is the most advanced in the world.’

Another Astute Class sub is currently undergoing sea trials – and could be operational within a year.

Many details of HMS Ambush’s weapons systems cannot be revealed for security reasons.

Most of her 103-strong crew live in bunk-beds measuring two metres by one metre, with up to 18 submariners sharing one room.

After today’s launch HMS Ambush will begin sea trials before eventually beginning operations.