The 2011 Nobel Prize in physics, awarded just a few weeks ago, went to research on the light from Type 1a supernovae, which shows that the universe is expanding at an accelerating rate. The well-known problem resulting from these observations is that this expansion seems to be occurring even faster than all known forms of energy could allow. While there is no shortage of proposed explanations – from dark energy to modified theories of gravity – it’s less common that someone questions the interpretation of the supernovae data itself.

In a new study, that’s what Arto Annila, Physics Professor at the University of Helsinki, is doing. The basis of his argument, which is published in a recent issue of the Monthly Notices of the Royal Astronomical Society, lies in the ever-changing way that light travels through an ever-evolving universe.

“The standard model of big bang cosmology (the Lambda-CMD model) is a mathematical model, but not a physical portrayal of the evolving universe,” Annila told PhysOrg.com. “Thus the Lambda-CMD model yields the luminosity distance at a given redshift as a function of the model parameters, such as the cosmological constant, but not as a function of the physical process where quanta released from a supernova explosion disperse into the expanding universe.

“When the supernova exploded, its energy as photons began to disperse in the universe, which has, by the time we observe the flash, become larger and hence also more dilute,” he said. “Accordingly, the observed intensity of light has fallen inversely proportional to the squared luminosity distance and directly proportional to the redshifted frequency. Due to these two factors, brightness vs. redshift is not one straight line on a log-log plot, but a curve.”

As a result, Annila argues that the supernovae data does not imply that the universe is undergoing an accelerating expansion.

The principle of least time

As Annila explains, when a ray of light travels from a distant star to an observer’s telescope, it travels along the path that takes the least amount of time. This well-known physics principle is called Fermat’s principle or the principle of least time. Importantly, the quickest path is not always the straight path. Deviations from a straight path occur when light propagates through media of varying energy densities, such as when light bends due to refraction as it travels through a glass prism. 

The principle of least time is a specific form of the more generally stated principle of least action. According to this principle, light, like all forms of energy in motion, always travels on the path that maximizes its dispersal of energy. We see this concept when the light from a light bulb (or star) emanates outward in all available directions.

Mathematically, the principle of least action has two different forms. Physicists almost always use the form that involves the so-called Lagrangian integrand, but Annila explains that this form can only determine paths within stationary surroundings. Since the expanding universe is an evolving system, he suggests that the original but less popular form, which was produced by the French mathematician Maupertuis, can more accurately determine the path of light from the distant supernovae.

Using Maupertuis’ form of the principle of least action, Annila has calculated that the brightness of light from Type 1a supernovae after traveling many millions of light-years to Earth agrees well with observations of the known amount of energy in the universe, and doesn’t require dark energy or any other additional driving force.

(via A second look at supernovae light: Universe’s expansion may be understood without dark energy)

Micro Machinist Takes on Bug Brains

Wired: What is it that you do?

Gus Lott: I think of it as reverse robotics. We’re dealing with organisms that have evolved circuits and adaptive-learning algorithms—mostly worms, fruit flies, and rodents—and we’re trying to develop tools that reverse-engineer how these natural machines work. We’re trying to figure out how nature built its own algorithm.

(via Wired Magazine)

These are kind of perfect and simultaneously too light and in the same instance perfect.

fuckyeahexistentialism:

Peter Mendelsund re-imagines the covers of Kafka

marrypotter:

by Redmer Hoekstra

(via eirizu)

Snail Braille reader could read books to the blind

To most of us, Braille is largely a mystery. It feels really cool, but the idea of actually reading it is kind of a pipe dream. Our sense of touch simply is not as sensitive as that of a blind person. That is not a problem if you happen to have picked up a Braille book out of curiosity. If however, you have recently lost your eyesight, then this is a major problem. As with learning any new language, it takes time to adapt.

That time can be very frustrating, since writing and reading are still important forms of communication in our society. That is where a tool such as the Snail Braille reader could come in handy.

This tool takes Braille text, and by rolling over a straight line of Braille text, the machine is able to read the Braille, and then translate it into speech. The machine, which is capable of storing text for latter replay, can also be paired with a standard Bluetooth headset, similar to the ones you get with your cell phone. That is good news for students who want to study without having to search for the page in a book, or for people who like to hear the instructions while they are completing a task.

(via PhysOrg.com)

proofmathisbeautiful:

un:

(via tscp)

matthias pliessnig: amada bench

:O

“Pliessnig recently completed ‘amada’, a design for a private client who wanted a large bench flowing through his living space. The piece was designed to direct the sitter to face multiple directions. The seating unit is made entirely of air-dried responsibly harvested white oak that has been steam bent to create the curvaceous form of the bench.”

monstermadeofeyes:

eyeballmansion:

sakanaman:themurkydepths:crisaris:Brendan Monroe

“Hay fever sufferers can now see the face of their invisible enemy - thanks to these Scanning Electron Microscope images of pollen grains. A Swiss scientist named Martin Oeggerli, who uses the name Micronaut for his art, uses a Scanning Electron Microscope in his cellar to capture images of pollen grains. This picture shows a higher magnification of forget-me-not pollen on a petal.”

Oh, sumo, you’re such an interesting sport.

monstermadeofeyes:

elidontlie:

retrogasm:Via

thedailywhat:

Life-Altering Compact Camper of the Day: Based on the classic three-wheeled Piaggio Ape, Industrial designer Cornelius Comanns’s “Bufalino” camper appears slight at first glace, but its insides are spacious enough to hold a bed, two seating units, a “cooking zone,” a sink, a water tank, a refrigerator, several storage compartments, and other creature comforts typically found in larger RV’s.

[designboom.]

proofmathisbeautiful:

proofmathisbeautiful:

Incomplete Sphere by Thomas Briggs

In 2001 German photography artist Michael Wesely was invited by the Museum of Modern Art in New York to use his unique technique to record the re-development of their building. He set up four cameras in four different corners and photographed the destruction and re-building of the MoMa until 2004 - leaving the shutter (the holes) open for up to 34 months!

(click on photo for more)

unknownskywalker:

Mars - just add water © Frieso J. Hoevelkamp

Scale Model of the Orbits of the Planets