In relativity, time is certainly an integral part of the very fabric of the universe and The complete history of a particular point in space is represented by a line in . to the speed of light) with respect to one another, such intuitive relationships. May 7, You need both a place and a time. Go to the profile of Milo Beckman Why would we think of it as a time-worm sitting in a pre-made. Nov 1, I've broken up with boyfriends, only to realize with time that an Well, before you even consider the conflicts going on in your relationship, ask.
To Einstein, time is the "fourth dimension.
Time provides another coordinate — direction — although conventionally, it only moves forward. Conversely, a new theory asserts that time is "real. French Einstein's theory of special relativity says that time slows down or speeds up depending on how fast you move relative to something else.
Approaching the speed of light, a person inside a spaceship would age much slower than his twin at home. Also, under Einstein's theory of general relativitygravity can bend time. Picture a four-dimensional fabric called space-time. When anything that has mass sits on that piece of fabric, it causes a dimple or a bending of space-time.
The bending of space-time causes objects to move on a curved path and that curvature of space is what we know as gravity. Both the general and special relativity theories have been proven with GPS satellite technology that has very accurate timepieces on board.
The effects of gravity, as well as the satellites' increased speed above the Earth relative to observers on the ground, make the unadjusted clocks gain 38 microseconds a day. Engineers make calibrations to account for the difference. In a sense, this effect, called time dilation, means astronauts are time travelers, as they return to Earth very, very slightly younger than their identical twins that remain on the planet. Through the wormhole General relativity also provides scenarios that could allow travelers to go back in time, according to NASA.
Time Travel: Theories, Paradoxes & Possibilities
The equations, however, might be difficult to physically achieve. One possibility could be to go faster than light, which travels atmiles per secondkilometers per second in a vacuum.
Einstein's equations, though, show that an object at the speed of light would have both infinite mass and a length of 0. This appears to be physically impossible, although some scientists have extended his equations and said it might be done. A linked possibility, NASA stated, would be to create "wormholes" between points in space-time.
Time Travel: Theories, Paradoxes & Possibilities
While Einstein's equations provide for them, they would collapse very quickly and would only be suitable for very small particles. Also, scientists haven't actually observed these wormholes yet. Also, the technology needed to create a wormhole is far beyond anything we have today. Alternate time travel theories While Einstein's theories appear to make time travel difficult, some groups have proposed alternate solutions to jump back and forth in time.
Infinite cylinder Astronomer Frank Tipler proposed a mechanism sometimes known as a Tipler Cylinder where one would take matter that is 10 times the sun's mass, then roll it into very long but very dense cylinder. After spinning this up a few billion revolutions per minute, a spaceship nearby — following a very precise spiral around this cylinder — could get itself on a "closed, time-like curve", according to the Anderson Institute.
There are limitations with this method, however, including the fact that the cylinder needs to be infinitely long for this to work. An artist's impression of a black hole like the one weighed in this work, sitting in the core of a disk galaxy. The black-hole in NGC weighs , times more than our own Sun. The ship and its crew would be traveling through time," physicist Stephen Hawking wrote in the Daily Mail in Ten years would pass elsewhere.
When they got home, everyone on Earth would have aged five years more than they had. Cosmic strings Another theory for potential time travelers involves something called cosmic strings — narrow tubes of energy stretched across the entire length of the ever-expanding universe.
These thin regions, left over from the early cosmos, are predicted to contain huge amounts of mass and therefore could warp the space-time around them. The approach of two such strings parallel to each other would bend space-time so vigorously and in such a particular configuration that might make time travel possible, in theory. Time machines It is generally understood that traveling forward or back in time would require a device — a time machine — to take you there.
Time machine research often involves bending space-time so far that time lines turn back on themselves to form a loop, technically known as a "closed time-like curve.
BBCAmerica To accomplish this, time machines often are thought to need an exotic form of matter with so-called "negative energy density. Such matter could theoretically exist, but if it did, it might be present only in quantities too small for the construction of a time machine.
However, time-travel research suggests time machines are possible without exotic matter. The work begins with a doughnut-shaped hole enveloped within a sphere of normal matter. Inside this doughnut-shaped vacuum, space-time could get bent upon itself using focused gravitational fields to form a closed time-like curve. To go back in time, a traveler would race around inside the doughnut, going further back into the past with each lap. This theory has a number of obstacles, however.
Anyone moving at a constant speed should observe the same physical laws. Putting these two ideas together, Einstein realized that space and time are relative -- an object in motion actually experiences time at a slower rate than one at rest.
Although this may seem absurd to us, we travel incredibly slow when compared to the speed of light, so we don't notice the hands on our watches ticking slower when we're running or traveling on an airplane. Scientists have actually proved this phenomenon by sending atomic clocks up with high-speed rocket ships.
Relativistic Time – Exactly What Is Time?
They returned to Earth slightly behind the clocks on the ground. What does this mean for the Captain Kirk and his team? The closer an object gets to the speed of light, that object actually experiences time at a significantly slower rate. If the Enterprise were traveling safely at close to the speed of light to the center of our galaxy from Earth, it would take 25, years of Earth time. For the crew, however, the trip would probably only take 10 years.General Relativity & Curved Spacetime Explained! - Space Time - PBS Digital Studios
Although that timeframe might be possible for the individuals onboard, we're presented with yet another problem -- a Federation attempting to run an intergalactic civilization would run into some problems if it took 50, years for a starship to hit the center of our galaxy and come back. So the Enterprise has to avoid the speed of light in order to keep the passengers onboard in synch with Federation time.
At the same time, it also must reach speeds faster than that of light in order to move around the universe in an efficient manner. Unfortunately, as Einstein states in his Special Theory of Relativity, nothing is faster than the speed of light.
Space travel therefore would be impossible if we're looking at the special relativity.