Alcubierre Warp Drive

Ever since the sound barrier was broken, people have turned their attention to how we can break the light speed barrier….?

But for that we have to fight against the … Theory of relativity ….

Theory of Relativity is one of the most successful and well known theory which explains the how gravity works using space time Fabric …

In Theory of relativity one thing is specified which leads may scientists to disappointment, that concept is “Nothing can move faster than speed of light “

(Although we now know that there are particle like A tachyon that possible exceed speed of light …but let’s leave it to some another time.. )

For now, let’s talk about not violating any relativity prediction,

In that case if we have to find a middle solution that follow the principle of physics and also we can use it as a space ship to travel the interstellar cosmos (Hint: something you saw in star trek )

Many years scientist are finding the solution for above question …
And finally in 1994 Mexican physicist Miguel Alcubierre find loophole …

Yes, there is loophole is theory of relativities and by manipulating or I can say “wrapping” space time fabric we can get our solution without violating fundamental of physics (in our case speed of light)….

Although this idea is still theoretical, but many space organization like NASA, Tau Zero Foundation and Icarus Interstellar are working on this …

So let’s get to know more about this amazing theoretical concept…

Ok so this is about the not violating the fundamental law …
Now let’s understand the idea of “Wrap Drive”
So the idea is to create a bubble in which we put our space ship and that bubble will travel faster …
How ?

For that you need a space time fabric and stretching …
Warp Drive stretches space-time (fabric) in a wave causing the fabric of space ahead of a spacecraft to contract and the space behind it to expand. An object inside this wave (i.e. a spaceship) would then be able to ride this region, known as a "warp bubble" of flat space.
This is what is known as the "Alcubierre Metric". Interpreted in the context of General Relativity, the metric allows a warp bubble to appear in a previously flat region of spacetime and move away, effectively at speeds that exceed the speed of light. The interior of the bubble is the inertial reference frame for any object inhabiting it.

To make it more simple, we are creating a wave like structure (down from front and up from back) in same space time fabric in which we are right now and we put it our space ship (which is always on flat fabric) into it so our bubble which made of space time fabric can move faster in space time itself and our spaceship will travel along with it .
To give you an brief idea it’s something like exilator (not totally just concept ) where we just stand (in our case our space ship) and our bubble of space time will move in space time it self (as you notices the down from front and up from back is the shape ) is like wave ..

Mathematically, it can be represented by the following equation: ds2= – (a2 – BiBi) dt2 + 2Bi dxi dt + gijdxi dxj, where a is the lapse function that gives the interval of proper time between nearby hypersurfaces, Bi is the shift vector that relates the spatial coordinate systems on different hypersurfaces and gij is a positive definite metric on each of the hypersurfaces

If everything including equation are there what are we waiting for right ?
What are the difficulties we face to make this ..?

Problems

• First one is create such a warp bubble in a region of space that would not already contain one. It requires exotic matter, the need for exotic matter leads to questions about whether it is actually possible to find a way to distribute the matter in an initial spacetime which lacks a “warp bubble” in such a way that the bubble will be created at a later time.
• Another problem according to Serguei Krasnikov is that it would be impossible to generate the bubble without being able to force the exotic matter to move at locally FTL speeds, which would require the existence of tachyons. Some methods have been suggested which would avoid the problem of tachyonic motion, but would probably generate a naked singularity at the front of the bubble.

But there are many solution offer for this difficulties

• Dr. Alcubierre said that starting with the vast amounts of exotic matter that would be needed. “The warp drive on this ground alone is impossible,” he said. “At speeds larger than the speed of light, the front of the warp bubble cannot be reached by any signal from within the ship,” he said. “This does not just mean we can’t turn it off; it is much worse. It means we can’t even turn it on in the first place.”
• Previous studies estimated the warp drive would require a minimum amount of energy about equal to the mass-energy of the planet Jupiter. But recently White calculated what would happen if the shape of the ring encircling the spacecraft was adjusted into more of a rounded donut, as opposed to a flat ring. we found in that case, the warp drive could be powered by a mass about the size of a spacecraft like the Voyager 1 probe NASA launched in 1977.

Ok so these is what we know till now in theoretical sense, now let’s talk about companies that actually working on this concept..

• In 1996, NASA founded a research project known as the Breakthrough Propulsion Physics Project (BPP) to study various spacecraft proposals and technologies. In 2002, the project's funding was discontinued, which prompted the founder – Marc G. Millis – and several members to create the Tau Zero Foundation. Named after the famous novel of the same name by Poul Anderson, this organization is dedicated to researching interstellar travel.
  In 2012, NASA's Advanced Propulsion Physics Laboratory (aka. Eagleworks) announced that they had began conducting experiments to see if a "warp drive" was in fact possible. This included developing an interferometer to detect the spatial distortions produced by the expanding and contracting space-time of the Alcubierre metric.
• The team lead – Dr. Harold Sonny White – described their work in a NASA paper titled Warp Field Mechanics 101. He also explained their work in NASA's 2012 Roundup publication:
  He called the project a "humble experiment" compared to what would be needed for a real warp drive, but said it represents a promising first step.
  "We've initiated an interferometer test bed in this lab, where we're going to go through and try and generate a microscopic instance of a little warp bubble. And although this is just a microscopic instance of the phenomena, we're perturbing space time, one part in 10 million, a very tiny amount… The math would allow you to go to Alpha Centauri in two weeks as measured by clocks here on Earth. So somebody's clock onboard the spacecraft has the same rate of time as somebody in mission control here in Houston might have. There are no tidal forces, no undue issues, and the proper acceleration is zero. When you turn the field on, everybody doesn't go slamming against the bulkhead, (which) would be a very short and sad trip."
  In 2013, Dr. White and members of Eagleworks published the results of their 19.6-second warp field test under vacuum conditions. These results, which were deemed to be inconclusive, were presented at the 2013 Icarus Interstellar Starship Congress held in Dallas, Texas.