Stephen Hawking once said “If black holes can be manipulated or manufactured in the lab to act as a time machine, then surely someone, somewhere in the universe must have developed the capability by now? Or at least, one day, someone will. So-then where are they?’ This statement can be expanded as if we’ve never met a time traveler then time machines could never exist.
Frank Tipler stated that A device based on an artificially created black hole wold only allow travel back to a period after it was created. This means it would not work straight away and that because we have not created one yet then no time traveler could get here. This paragraph you could say answers the articals title question.
These two paragraphs seem to show that time machines don’t exist but lets take a look and see if it can be disproved or not.
We ourselves could be classed as time machines as we travel forward in time as we go through life from birth to death.
You could say that planes and other fast moving vehicles are time machines.
When you travel on an aeroplane you cross time zones hence you travel in time but this does not make the plane a time machine. When using relativity to explain the effects of traveling on a plane we can then show that they could be time machines.
Relativity experiments show that if you synchronise two identical atomic clocks and then leave one one the ground and place the other in an aircraft, sending it on a round the world trip, when you compare them at the end of the trip the one on the plane will be slightly slower than the one that had been left on the ground. You could then say that the occupants of the plane have traveled into the future making the plane a time machine.
Light itself is a form of time machine allowing us see into the universes past.
Lets look at an experiment that could be the the next step in creating the first time machine.
During the final part of the 20th century and into the 21st century scientists have been doing experiments concerning Bose-Einstein Condensates.
These condensates are created by cooling atoms and taking their temperature to absolute zero. Their existence was first theorised by Albert Einstein and Satyendra Bose in 1925, but their theories could not be tested at the time because there was no technology advanced enough to do so. It was not until 1995 seventy years later that their theory was actually proved in an experiment at the University of Colorado at Boulder NIST-JILA lab by Eric Cornell and Carl Wieman. They cooled rubidium atoms down to 170 nanokelvin creating a huge cloud of gas with an undefined size and shape and properties and behaviors that are currently not completely understood.
What does this have to do with Time travel? When you cool things down to absolute zero all motion stops, so the particles making up an atom will have no velocity, meaning momentum will be zero. In later experiments scientists shone light in to the cloud to see what would happen. In the first known experiment of this type the light’s speed was slowed from its normal 186,000 miles per second down to a crawl of 38 miles per hour as it moved through the cloud of the condensate. The slowing of light is the first step in defeating the time barrier and the Bose-Einstein condensate could be the first step to creating a working time machine.
So in essence there are machines that can take you a up to a second or so into the future, slow down time and we can look back into the past when we look at the stars, but the first paragraph does seem to ring true in that there are no machines that can take you pack to the past or further into the future.
