Wunderjahr — The year that redefined physics!
The year 1905 saw four papers being published by a patent clerk named (take a guess!) Albert Einstein and since then the world hasn’t been the same. Let’s take a look at what made these papers so remarkable.
The history of science has been one long series of violent brainstorms, as successive generations have come to terms with increasing levels of queerness in the universe. — Richard Dawkins
All of us have certain years that we consider to be our best years, whether it be due to an array of achievements or just the general vibe of those years (obviously not counting 2020 or for that matter 2021). But it is very rare that our best years change the whole course of history or our understanding of the universe. Nonetheless, we do have some years that stand out like a pillar in the passage of time — years that change the future in a big way for better or worse and sometimes, the reason behind such momentous years is only one individual. 1905 was one such year, a year that redefined our understanding of physics and the universe and started a chain of events that took humans to the moon and back and also provided humanity with the power to eliminate themselves with just one button. In hindsight, one can look back and ask themselves how can one individual change that much in just one year? Well, the answer is — by publishing an academic paper that literally challenged scientific theories established through centuries and then repeating this step three more times in that same year. Now the obvious question that one can ask is — how does one do that? Well, we don’t know! You have to invent artificial intelligence and stealthily steal a brain from the Mutter Museum, recreate it and ask Albert Einstein himself. Einstein probably would suggest getting a doctorate in physics and starting working in a patent office, which might not be as cool as it sounds.
Having made all that build-up, it is only fair we tell you the story behind all of this. So the story goes as follows:
In 1905, Einstein, while working as a clerk at the patent office in Bern (Switzerland), sent four papers to the German scientific journal Annales der Physik. Before that, his doctoral thesis was rejected and he had to work at a patent office to sustain himself. Doing the scientific research on the side, while having conversations with his friend and colleague Michele Besso, he wrote four academic papers covering fields like light, time, space and energy. Due to the revolutionizing nature of the papers, scholars in the late 20th century dubbed 1905 as Annus Mirabilis, “the miracle year” or Wunderjahr in German. There is a lot to be said about why these papers built the foundation of modern science, but the beauty of these papers lies in the fact that all of them challenged the previously held theories and it took a lot of time for the public or even scientific community to accept these papers and do some serious research on them. We will take a brief look at all these papers and understand the underlying magic that Einstein weaved.
Photoelectric effect (June 9, 1905)
“Über einen die Erzeugung und Verwandlung des Lichtes betreffenden heuristischen Gesichtspunkt” (“On a Heuristic Viewpoint Concerning the Production and Transformation of Light”)
“According to the assumption to be contemplated here, when a light ray is spreading from a point, the energy is not distributed continuously over ever-increasing spaces, but consists of a finite number of energy quanta that are localized in points in space, move without dividing, and can be absorbed or generated only as a whole.”
Regarded as one of the most important statements of the 20th century, this claim set the foundation of quantum mechanics and gave rise to the century of new science. Expanding on the idea of Max Plank on the derivation of black-body radiation, Einstein hypothesized the photoelectric effect, which later also won him the Nobel prize in 1921. The theory was remarkable in the sense that it established the duality of the nature of light. Until 1905, everyone was sure of the wave nature of the light but with this paper, Einstein shed light on the particle nature of light, which was for a long time not accepted by many peer scientists. Einstein knew his idea to be revolutionary and waited for two decades for it to be finally accepted everywhere.
Brownian motion (July 18, 1905)
“Über die von der molekularkinetischen Theorie der Wärme geforderte Bewegung von in ruhenden Flüssigkeiten suspendierten Teilchen” (“On the Motion of Small Particles Suspended in a Stationary Liquid, as Required by the Molecular Kinetic Theory of Heat”)
“According to the molecular kinetic theory of heat, bodies of a microscopically visible size suspended in liquids must, as a result of thermal molecular motions, perform motions of such magnitudes that they can be easily observed with a microscope.”
Even though this paper is regarded as the least important when compared to the other three, it formed the foundation of the field we now call Statistical Physics. Most scientists had accepted the idea that matter is composed of atoms, but there were still many who were not on board with it. Einstein’s paper on this motion empirically and mathematically confirmed the existence of atoms, finally resting the debate on the composition of matter and yet opening it up to further questioning.
Special relativity (September 26, 1905)
“Zur Elektrodynamik bewegter Körper” (“On the Electrodynamics of Moving Bodies”)
“The same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good. We will raise this conjecture (the purport of which will hereafter be called the “Principle of Relativity”) to the status of a postulate, and also introduce another postulate, which is only apparently irreconcilable with the former, namely, that light is always propagated in empty space with a definite velocity c which is independent of the state of motion of the emitting body.”
The special theory of relativity or the general theory of relativity is often cited in many conversations by a whole group of people that might not even understand the theories. But this shows the depth that these theories hold. Einstein’s third paper that year was one of the most remarkable works done in the history of physics because it not only combined electrodynamics and mechanics but also changed our understanding of time. Its impact has still not fully unfolded in many other areas of study, like social sciences. Einstein challenged the most basic idea that time runs differently for different observers, which was impossible in Newtonian mechanics, and the rest is history. The special theory gained widespread acceptance remarkably quickly, which was astonishing since it challenged some very basic ideas of physics. It also further paved the way for a general theory, which took Einstein the next 10 years to work out and was presented in 1915.
Mass–energy equivalence (November 21, 1905)
“Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig?” (“Does the Inertia of a Body Depend Upon Its Energy Content?”)
“If a body gives off the energy L in the form of radiation, its mass diminishes by L/c^2. The fact that the energy withdrawn from the body becomes the energy of radiation evidently makes no difference, so we are led to the more general conclusion that the mass of a body is a measure of its energy content; if the energy changes by L, the mass changes in the same sense by L/(9 × 10^20), the energy is measured in ergs, and the mass in grammes.”
Well, there is one equation that everyone outside the scientific community is aware of, and that came from the conclusion of this paper, which established the equivalence between mass and energy. Even though it was a groundbreaking achievement, its applications were marred by the human tendency to make the worse out of everything. The discovery that we can generate energy through nuclear reactions led to the atomic bomb being dropped on Japanese cities, forty years after the Annus Mirabilis. Even though the result was something Einstein didn’t anticipate, the discovery itself changed our understanding of the cosmos and brought forward several new scientific fields that are flourishing now like nuclear physics, statistical physics and many more.
E= mc²
“One of the saddest lessons of history is this: If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken. Once you give a charlatan power over you, you almost never get it back” — Carl Sagan
Our tendency to not change or accept new ideas can be our shortcoming, but there will always be individuals who challenge the status quo. Standing on the shoulders of giants, Einstein showed us the universe in a new way. There might come a time when these theories might also be challenged but until then Annus Mirabilis and the genius of Einstein have paved the way for numerous scientific breakthroughs which have put humanity in the driving seat.
This article was written by Atotmyr and edited by Vagisha Bhatia. Stay tuned for more articles!
References -
https://en.wikipedia.org/wiki/Annus_mirabilis_papers
https://www.bbvaopenmind.com/en/science/leading-figures/einsteins-miracle-year/
