"We are like dwarfs sitting on the shoulders of giants. We see more, and things that are more distant, than they did, not because our sight is superior or because we are taller than they, but because they raise us up, and by their great stature add to ours." This tumblr's for all the great men and women of science for whom we owe our current understanding of the natural world; their achievements, their failures, and even their quirks, we celebrate them all.
For Science. For Inquiry. For Humanity.
The Mystery of Einstein’s Last Words
On April 17th, 1955, Albert Einstein experienced internal bleeding caused by the rupture of an aneurysm, which had previously been reinforced by surgery in 1948. Einstein refused surgery, saying: “I want to go when I want. It is tasteless to prolong life artificially. I have done my share, it is time to go. I will do it elegantly.” He died in Princeton Hospital early the next morning at the age of 76, having continued to work until near the end.
Before Einstein passed away in his sleep that night, Einstein uttered his final words to the nurse caring for him. In a tragic loss to history, he said these words in German - a language that the nurse did not speak. At the time of his death, the physicist was writing a piece, which ended abruptly mid-sentence, “Political passions, once they have been fanned into flame, exact their victims…”
Charles-Augustin de Coulomb (1736-1806)
In 1784 Coulomb began studying the interaction forces of charged particles in depth. Using a torsion balance Coulomb discovered that for point charges, charged bodies that are very small compared to the distance r between them, the electric force is proportional to
Meaning when r doubles the force decreases to 1/4 of the initial value.
Coulomb also found that the electric force between two point charges also depends on the quantity of charge on each body, known as q. He studied this further by dividing a charge into two equal parts by putting a small charged spherical conductor in contact with an identical, uncharged sphere. Through the principle conservation of charge the charge is equally shared between the two spheres. By doing this he could now obtain 1/2, 1/4, 1/8, etc. of the initial charge.
What he discovered was that the forces that two point charges, q1 and q2, exert on each other are proportional to each charge, thus proportional to the product of q1 and q2 of the two charges.
His findings then gave us Coulomb’s law which states:
The magnitude of the electric force between two point charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
In mathematical terms it is stated as such
where k is a constant of proportionality in which its value depends on the system of units used. In SI units the constant k is
The value k is known to a number of significant digits because the value is related to the speed of light in a vacuum. In fact k can be written in terms of c
But often k is seen to be written as
where epsilon-zero is another constant equal to
While it seems to complicate Coulomb’s law it deems itself worthy in a few electrical encounters.
Spacetime is a single substance; to talk about space and time separately is nonsensical. When you want to travel in time, you must also consider travelling in space (see above). So when anyone mentions travelling backward or forward in space and time, one must consider the complicated nature of physical location in that. There is a lot to consider there. The earth is moving, the Sun is moving, the galaxy is moving, the universe is expanding. This is another reason that time travel as we imagine it is a lot further off than we would all like to hope.
(via astrotastic)
Sharks are known as extremely fast and agile swimmers, due in part to the surface of their skin. Sharks are covered in very tiny tooth-shaped scales called denticles which are streamlined in the direction of flow over the shark. If you were to run a hand over a shark’s skin from head to tail, it would feel silky smooth, but rub against the grain and it’s like running your hand on sandpaper. Water encounters a similar resistance, which, according to new research, provides the shark with a passive flow control mechanism, requiring no effort on the part of the shark. When water near the shark’s denticles tries to reverse direction, an early stage in flow separation, the denticles naturally bristle, slowing and trapping the reversed flow. This prevents local flow separation which would otherwise increase the shark’s drag and hinder its agility. (Photo credit: James R. D. Scott; Research by A. Lang et al.)
(via ikenbot)
THE COSMOS
“For my final year degree show project, I wanted to capture the essence of mankind’s fascination with the stars. Titled, The Cosmos, the project details mankind’s ancient fascination and constant relationship with space and the cosmos. From ancient Egypt through to the exciting space race of the 1960s – mankind has always looked to the stars and seen his or her future. Atomically Earth and all it’s inhabitants are no different from the far flung galaxies, we are all made of star stuff – space itself represents our globally shared dream of exploration into the final frontier and the unknown.”
Visit the complete gallery on Behance
(via astrotastic)
The Beautiful Blackboards of Quantum Physics Labs
Alejandro Guijarro visited the world’s finest quantum physics labs to record their half-erased blackboards. In an era where science is increasingly all-digital, it’s a striking reminder that science is still an active, hands-on process, a process here captured in layers of smeared chalk.
Happy Birthday to Stephen Hawking!
The celebrated physicist is 71 years old today. One of our era’s most brilliant minds, he has contributed both to cosmological science as well as to the public’s understanding of the natural world. All this despite being diagnosed with Lou Gehrig’s disease 50 years ago, a diagnosis that usually means one has years to live, not decades. He is an example of both the strength of the human spirit and the power of the human mind.
Celebrate by watching his 1992 film A Brief History of Time, free in its entirety, at Open Culture.
Oh, and it’s also Elvis Presley’s birthday or something.
(via the-star-stuff)
