What is the smallest unit of time you can conceive? A second? A millisecond? Hard to say seeing as how time is relative. Under the right circumstances, hours can fly by and seconds can feel like a lifetime. But unfortunately for physicists, time is not something that can be delt with so philosophically. And since they deal with cosmological forces both infinitesimally large and small, they need units that can objectively measure them. When it comes to dealing with the small, Planck Time is the measurement of choice. Named after German physicist Max Planck, the founder of quantum theory, a unit of Planck time is the time it takes for light to travel, in a vacuum, a single unit of Planck length. Taken together, they part of the larger system of natural units known as Planck units.
Originally proposed in 1899 by German physicist Max Planck, Planck units are physical units of measurement defined exclusively in terms of five universal physical constants. These are the Gravitational constant (G), the Reduced Planck constant (h), the speed of light in a vacuum (c), the Coulomb constant(ke or k), and Boltzmann’s constant (kB, sometimes k). Each of these constants can be associated with at least one fundamental physical theory: c with special relativity, G with general relativity and Newtonian gravity, with quantum mechanics, with electrostatics, and kB with statistical mechanics and thermodynamics. They were invented as a means of simplifying the particular algebraic expressions appearing in theoretical physics, especially in quantum mechanics.
Ultimately, Planck time is derived from the field of mathematical physics known as dimensional analysis, which studies units of measurement and physical constants. The Planck time is the unique combination of the gravitational constant G, the relativity constant c, and the quantum constant h, to produce a constant with units of time. They are often semi-humorously referred to by physicists as “God’s units” because eliminate anthropocentric arbitrariness from the system of units, unlike the meter and second, which exist for purely historical reasons and are not derived from nature. Some challenges to Planck’s Time have been mounted. For example, in 2003 during the analysis of the Hubble Space Telescope Deep Field images, some scientists speculated that where there are space-time fluctuations on the Planck scale, images of extremely distant objects should be blurry. The Hubble images, they claimed, were too sharp for this to be the case. Other scientists disagreed with this assumption however, with some saying the fluctuations would be too small to be observable, others saying that the speculated blurring effect that was expected was off by a very large magnitude. A unit of Planck Time can be expressed (in the third picture).
Read more: http://www.universetoday.com/79418/planck-time/#ixzz2U4Nz4Ov1
There’s this British wartime poster that’s moved from historical artifact into commercialized meme; a red background with words “Keep Calm and Carry On” block printed in white below the Crown of the United Kingdom. If you’ve spent any time online in the last few years you’ll be familiar with it, but it once had a purpose beyond the basis for countless remixed image macros.
In the 1940 the German Air Force (the Luftwaffe) unleashed a 267 day bombing of England and Scotland, killing 40,000 people in 8 months, dropping 100 tonnes of explosives across all the major cities in Britain, including 57 consecutive nights over London. The British, we, stood firm against the attacks, eventually turning the tide and defended Britain once again. The poster, produced a year earlier at the start of the war, was one among many that helped wage the cultural war on home soil in the face of an enemy who was using the most sophisticated and deadly weapons of the time to defeat us.
You see, resolution in the face of danger is the most British characteristic, keeping calm and carrying on isn’t just a catchphrase, it almost fundamentally encapsulates what it is to be British, resolute, calm, determined, unwavering.
When a 48 year old Cub scout leader Ingrid Loyau-Kennett stares down a cleaver wielding murderer and attempts to reason with him in the middle of a London street on a sunny Wednesday afternoon, it’s not just a solitary act of incredible bravery (which it is) but its something that I couldn’t imagine happening anywhere else, at least not by anyone else but the British.
It’s who we are. We keep calm. We carry on.
Quick, someone teach Marissa to count to 140.
“I’ll never forget the day Marilyn and I were walking around New York City, just having a stroll on a nice day. She loved New York because no one bothered her there like they did in Hollywood, she could put on her plain-jane clothes and no one would notice her. She loved that. So as we we’re walking down Broadway, she turns to me and says ‘Do you want to see me become her?’ I didn’t know what she meant but I just said ‘Yes’- and then I saw it. I don’t know how to explain what she did because it was so very subtle, but she turned something on within herself that was almost like magic. And suddenly cars were slowing and people were turning their heads and stopping to stare. They were recognizing that this was Marilyn Monroe as if she pulled off a mask or something, even though a second ago nobody noticed her. I had never seen anything like it before.” - Amy Greene, wife of Marilyn’s personal photographer Milton Greene