The Surprising History Behind Leap Year by Brian Handwerk [National Geographic]
The ancient Egyptians did it, and so do we. Here's how a leap day—which occurs Februrary 29—helps keep our calendars and societies in sync. It's that time again: This Monday, February 29, is a leap day, the calendar oddity that occurs (almost) every four years. For centuries, trying to sync calendars with the length of the natural year caused confusion—until the concept of leap year provided a way to make up for lost time.[more inside]
Trek at 50: The quest for a unifying theory of time travel in Star Trek by Xaq Rzetelny [Ars Technica] [more inside]
Today The Doomsday Clock will have its time recalibrated. In 2015 the scientists set the hands to 23.57 - "due to climate change, the modernization of nuclear weapons in the United States and Russia, and the problem of nuclear waste." Is the apocalypse closer or further away? Watch the result live at 13.30 EST. There's really only one way it can go.
Explore the deepest mysteries at the frontier of fundamental physics, and the most promising ideas put forth to solve them. A map of the frontier of fundamental physics built by interactive developer Emily Fuhrman.
"Erik, photojournalist, and I have come here to try and get the measure of this place. Nevada is the uncanny locus of disparate monuments all concerned with charting deep time, leaving messages for future generations of human beings to puzzle over the meaning of: a star map, a nuclear waste repository and a clock able to keep time for 10,000 years—all of them within a few hours drive of Las Vegas through the harsh desert." -- Built For Eternity, Elmo Keep on structures designed to potentially outlast human civilization. (Motherboard)
In its December 5, 1994 issue, Time Magazine picked 50 people who would be leaders in the future. They decided to revisit what happened to each person on the 20th anniversary of their predictions.
In a Multiverse, What Are the Odds? "Testing the multiverse hypothesis requires measuring whether our universe is statistically typical among the infinite variety of universes. But infinity does a number on statistics." (previously) [more inside]
World's longest-running experiment captures elusive tar pitch drop fall on video after 84 years of waiting — though, sadly, too late for physicist and former pitch drop custodian Prof. John Mainstone, who passed away last year.
Chief Scientist Demetrios Matsakis gives us a tour of the U.S. Naval Observatory's Time Services and explains where time comes from.
A Black Hole Mystery Wrapped in a Firewall Paradox - "A paradox around matter leaking from black holes puts into question various scientific axioms: Either information can be lost; Einstein's principle of equivalence is wrong; or quantum field theory needs fixing." [more inside]
A Renaissance in Economics The American President Ronald Reagan once quipped, “The nine most terrifying words in the English language are, ‘I’m from the government and I’m here to help.’” I get the same shivers when someone introduces themselves as an economist.
The Nature of Computation - Intellects Vast and Warm and Sympathetic: "I hand you a network or graph, and ask whether there is a path through the network that crosses each edge exactly once, returning to its starting point. (That is, I ask whether there is a 'Eulerian' cycle.) Then I hand you another network, and ask whether there is a path which visits each node exactly once. (That is, I ask whether there is a 'Hamiltonian' cycle.) How hard is it to answer me?" (via) [more inside]
Here is Coffee: The Greatest Addiction Ever and other neat videos by C.G.P. Grey who explains non-obvious aspects of science, history, geography, elections, and economics in entertaining and clear ways. [more inside]
The concept of time as a way to measure the duration of events is not only deeply intuitive, it also plays an important role in our mathematical descriptions of physical systems. For instance, we define an object’s speed as its displacement per a given time. But some researchers theorize that this Newtonian idea of time as an absolute quantity that flows on its own, along with the idea that time is the fourth dimension of spacetime, are incorrect. They propose to replace these concepts of time with a view that corresponds more accurately to the physical world: time as a measure of the numerical order of change.
A DNA test has proven that a man was executed for murder by the State of Texas on the basis of false forensic evidence. [more inside]
Asteroid Discovery From 1980 - 2010: an animation of the solar system that highlights asteroids as they are discovered. I would suggest watching it in a high resolution.
Year On Earth breaks it down, explaining the complicated mechanics involved in trying to determine how long a year really is, why seasons and ice ages happen, and how not all years are created equal.
Rules for Time Travelers [Spoiler? alert.]
Flow of Time is a BBC documentary that "tries to explain time and covers the different ways we have used to understand Time, religion, mathematics, relativity, and quantum mechanics." Part 1, 2, 3, 4
A Profound Sense of Time. "PZ Myers on the process that prompts the growth of all vertebrates from embryos to unspecialized segments to multicellular animals."
The New "Science" of Siblings An amusing article from Time magazine by Jeffrey Kluger which reports that your siblings have more influece on your personality than any other group-- parents, peers, spouses, children, etc. My ex-wife thinks I'm sarcastic, combative, insensitive, etc. Do I get to blame my brothers and sisters for this now? Another article on this issue "The Science of Siblings". Apparently, they could have made me more likely to be gay too.
In one corner, precise astronomers who just want to keep things as they are. In the other, revisionist telecommunications officers. Fight!
"If time has to end, it can be described, instant by instant," Mr. Palomar thinks, "and each instant, when described, expands so that its end can no longer be seen." He decides that he will set himself to describing every instant of his life, and until he has described them all he will no longer think of being dead. At that moment he dies. In memoriam of Italo Calvino, who died exactly 20 years ago. "Calvino's novels" by his friend Gore Vidal. Calvino's obituary by Vidal, il maestro William Weaver's essay on Calvino's cities, Jeanette Winterson on Calvino's dream of being invisible, and Stefano Franchi's philosophical study on Palomar's doctrine of the void. More inside.
The False Controversy of Stem Cell Research. Kinsley: In fact, thinking it through is a moral obligation, especially if you are on the side of the argument that wants to stop or slow this research. It's not complicated. An embryo used in stem-cell research (and fertility treatments) is three to five days past conception. It consists of a few dozen cells that together are too small to be seen without a microscope. It has no consciousness, no self-awareness, no ability to feel love or pain. The smallest insect is far more human in every respect except potential.
The cable clock. This clocks tells time, just like any other clock, but the movement of the hands is hypnotic and beautiful. To physicists, time is defined by quantum mechanics. A photon with energy h (Planck's constant) behaves as though it were oscillating once per second. For Philosphers, time is less concrete, and they love to talk about it. Western society lives by the clock - does it make a difference if this is the kind of clock that you live by? After all, everyone knows that time is money. If you have to be a clock watcher, does it help if the clock is as calming as the Cable Clock is?
Just how plausable is time travel? Could you go back in time and kill your own grandfather?. Would you want to? Time travel is a popular subject for films, but do the writers work out exactly what is happening? Current opinion seems to be that time travel is only possible to the future, and is only one way, by travelling at near light speed. However despite this, time machines seem to already be on sale.