The Virgo Interferometer is something spectacular. With two arms 3km in length, it’s one of the biggest machines ever made in the history of the world, behind things like LIGO and the LHC. All for science.
But some mysterious figure didn’t just come up with it one day and had it approved for construction the next, the journey atop giants’ shoulders was long and wrought with complicated maths people like me could never hope to understand.
Today I thought it would be worthwhile putting some time aside to learn a little more about some of the giants who constructed this monolithic structure with the power of their brains - Einstein aside.
Henri Poincaré
Public Domain
A long, long time ago around 240BC, the Greek poet (also mathematician I guess) Eratosthenes decided to shove a stick in the ground in Alexandria, Egypt, and made another man travel to Southern Egypt to shove another stick in the ground there.
By measuring the difference in shadows at the same time of day, he managed to figure out that the earth was round, and how big it was to surprising accuracy of between 1% and 16% (depending on how you measure ‘stadia’), roughly around 44,100 km. Quite an accomplishment given we now know it’s about 40,075.017km. Give or take.
Though Eratosthenes managed to prove something he could not possibly see for himself - indeed we could not possibly see until space agencies took us into the Great Void Above - Poincaré decided he could essentially take this one step further do the same thing with the entire Universe.
We call this the Poincaré Conjecture, for which he is most famous. You can Learn more about it in this video, but in short it took over a century of people coming up with false proofs for his outlandish idea to inevitably become proven by an eccentric, isolated Russian, Grisha Perelman who went on to turn down a million dollars and the equivalent of a nobel prize, the Fields Medal, before fading back into obscurity.
But Poincaré is also responsible for first proposing the existence of gravitational waves, 11 years before Einstein made his predictions, something that both LIGO and VIRGO slipped up on in a publication a few years back, instead attributing to Einstein.
By building on the theory of special relativity and the Lorentz Transformations, he concluded that gravitation must emanate outwards, at the speed of light rather than instantaneously, as waves do - in a similar fashion to Electromagnetism.
A decade later, Einstein incorporated these ideas into his paper Approximative Integration of the Field Equations of Gravitation.
References
Sur la dynamique de l’électron | Henri Poincaré Predicted The Existence Of Gravitational Waves As Early As June 5, 1905
Oliver Heaviside
Public Domain
So Poincaré was the first, except… he wasn’t really.
Oliver Heaviside was a rather brilliant Englishman, having self-taught electrical engineering, mathematics, physics and more.
He was no mathematical amateur either. After stumbling upon Maxwell’s paper Treatise on Electricity and Magnetism. and describing it as:
Great, greater and greatest, with prodigious possibilities in its power
He buckled down for the better part of a decade studying Maxwell’s work with passion until finally following his own path.
In 1893, a full 23 years before Einstein’s predictions, Heaviside made some pretty bold deductions. In his paper A Gravitational and Electromagnetic analogy, he wanted to align gravitational energy with the likes of electric and magnetic energies a la Maxwell.
Upon considering velocity of propagation as finite, he continued his comparisons and concluded, roughly, the existence of gravitational waves.
References
The Prediction of Gravitational Waves in 1893 | The Secret History of Gravitational Waves
Pierre-Simon Laplace
Ok, so the idea that gravitation traveled at finite speeds was hardly new, with Laplace discussing this idea as far back as 1770. Numerous others had also touched on this, but the ideas, far from refined, required Poincaré and eventually Einstein to truly hammer home the details.
In fact, it was Einstein alone who made the tangible, accurate predictions alongside details of their expected properties, such as how the waves wilil exhibit stretching in one direction and compressing in the other, much like sound waves and light, but way more complicated regarding the manipulation of space-time.
But where’s the proof?
Introducing:
Kip Thorne, Barry Barish & Rainer Weiss
In 2017, these three lads won the nobel prize in Physics for the ‘decisive contributions to the LIGO detector and the observation of gravitational waves’!
In 1984, the three co-founded the LIGO project in the US, and suddenly those elusive gravitational waves were about to lose their hiding spot. All of Einstein/Poincaré/Heaviside/Laplace’s work was falling into place.
The workload was not a light one. Kip Thorne, for example, had to develop the mathematics in order to even be able to analyse the results should the experiment work, he had to analyse engineering designs that couldn’t conceptually be tested beforehand, he helped identify wave sources, provide theoretical support, he designed the beam tubes, and invented ‘quantum nondemolition designs’ and ways to reduce thermoelastic noise.
All in a day’s work!
Kip Thorne Credit: A. T. Service - CC BY-SA 3.0
On top of that, he even managed to squeeze in enough time to be the science advisor for Christopher Nolan’s ‘Interstellar’ - a movie that depicts the most scientifically accurate black hole known to date - a full 2 years before signatures of gravitational waves were officially detected.
References
And here we are now, in 2018 (that is also the beginning of what is coined the gastrophysics era), a world where gravitational waves are a definitely real thing that we can almost touch with our bare hands. Ok, not quite. Detecting one of these waves is the equivalent of noticing the Milky Way stretched out about the length of your keyboard’s delete key.
But we can touch the machines capable of doing that at say, oh I don’t know, the SteemSTEM-Utopian.io meetup in Italy in September!
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