Before we dive into this, you should understand that this is not one of those googoo-eyed premature predictions of scientists having figured out how to create artificial gravity. What it is, however, is the drawing together of information from different sources that we think may suggest that artificial gravity, as a concept from science fiction, might actually be possible to make into a real thing. The idea has been around almost as long as science fiction has, mainly because it is just easier to write space opera if there is something like gravity holding people’s feet to the deck plates and their butts in their chairs. Of course writers of books and short stories have always been free to write works where the space adventurers float weightlessly through the cabins and corridors of their ships, but in movies and television where making people float is a lot more expensive than just having them walk around, gravity has always been conveniently present1.
The first part of the story has to do with the recent possible detection of gravitational waves. For reference, gravity appears to us humans as a dimple in the fabric of space-time caused by objects with mass. The more mass an object has, the bigger the dimple and the greater the force of the gravity it exerts. Objects coming within range of the deformation of space-time, for lack of a simpler explanation, “fall into the dimple”.
But what happens if there is a ripple in the fabric of spacetime? Physicists at the Advanced Laser Interferometer Gravitational-Wave Observatory (Ligo) which uses detectors in Hanford, Washington, and Livingston, Louisiana, think they may have just found out. They haven’t made a public statement yet, but scientists on the team are in the process of writing up a paper that describes a gravitational wave signal. If such a signal exists and is verified, it would confirm one of the most dramatic predictions of Albert Einstein’s century-old theory of general relativity. They’re being circumspect about it because they’re not sure if the data they have and the corresponding maths hold up. The paper has to be internally vetted before it’s sent out for publication. Even then, they will invite cross examination and inspection of their findings by the world scientific community.
In September, the first rumors of gravitational wave detections made Nature, but respected Arizona State University physicist and author Lawrence Krauss said at the time, “I give it a 10 to 15 percent likelihood of being right.” No one more confident was willing to go on the record. Yesterday, however, Krauss changed his tune, tweeting: “My earlier rumor about LIGO has been confirmed by independent sources. Stay tuned! Gravitational waves may have been discovered!! Exciting.”
My earlier rumor about LIGO has been confirmed by independent sources. Stay tuned! Gravitational waves may have been discovered!! Exciting.
— Lawrence M. Krauss (@LKrauss1) January 11, 2016
Today, however, he tempered his previous statement with an admonition that he didn’t have a confirmation of it either:
To reporters: A rumor is a RUMOR. LIGO will make any announcement if there is one. I am not part of LIGO nor do I represent anyone there.
— Lawrence M. Krauss (@LKrauss1) January 12, 2016
The uncertainty seems to come from whether or not a particular detected signal was the result of a calibration test. Indications are that it wasn’t, but they’re still collecting data today, and it takes time to analyze, interpret and review the results.
That’s the first half of the news — that we may have confirmation that gravity waves are detectable. Here’s the other half: a new paper has been accepted for publication in Physical Review D appears to say that it might be possible to generate and manipulate our own artificial gravity fields. Professor André Füzfa, from the Universite de Namur in Belgium, has calculated that by using extremely strong magnets, it’s possible to create tiny distortions in space-time.
While the math is claimed to work (and not being physicists ourselves, we are unable to comment on it), the effect should be strong enough to be detectable at the particle level. This is comparable in scope to experiments in quantum teleportation where only a single photon or subatomic particle is affected. The theoretical starting point of Füzfa’s research is the equivalence principle. This states that the force experienced by an observer in a gravitational field is essentially the same as being accelerated in a direction opposing the apparent force of gravity. In simple terms, if you were in a spacecraft no windows, you would not be able to tell whether you were being pulled toward the deck by gravity, or the deck was pushing up from below you because the ship was accelerating in the direction of the cabin ceiling.
The assumption is that every mass and every type of energy are affected by and generate gravity, so it should be possible to create gravitational fields using intense magnetic fields. Füzfa worked out the calculations for Einstein’s general relativity equation around a powerful looping electromagnet, and the solution seems to show that a small but significant gravitational effect would be created. More importantly, he thinks it would be possible to test the theory using technology we have now. It wouldn’t be easy, or cheap. The magnetic fields need to be generated over many days using layers upon layers of superconductive magnets, as well as sophisticated and sensitive laser systems that can detect the small variation in gravity within the magnets. In short, the fields would be just enough to detect, but not enough to use.
While all this is progress, it’s still roughly akin to building a Formula 1 racing engine so that you can reheat cups of coffee on the exhaust manifold. A tremendous amount of energy has to be put into creating a related energy field to get this infinitesimal, almost accidental, byproduct. So much is still unknown, but there is reason to hope, for even a year ago we knew that these properties of the universe should be there, but no technology we possessed could have the slightest effect on them.
Will we have artificial gravity if the newly designed experiment is carried out? If one is willing to accept the idea that what we get will be almost but not quite completely unlike what science fiction fans and writers alike think of when the words “artificial gravity” are spoken, then yes. For now, the idea of artificial gravity such as might be used in human-habitable spacecraft is still just a romantic notion.
But now we, as a species, have something we did not have: we now understand at least a little of the science of it, and that’s enough of a tease to keep us asking more questions.
1We’re looking at you, Star Trek/Star Wars/Babylon 5/Space:1999/Lost In Space/George Meliés From The Earth To The Moon and, well, you get the idea.