Tuesday 7 October, 2014

The Nobel Prize in Physics 2014

The Nobel Prize in Physics 2014
Isamu Akasaki, Hiroshi Amano, Shuji Nakamura


The Nobel Prize in Physics 2014 was awarded jointly to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura "for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources".
The Nobel Prize in Physics 2014
Isamu Akasaki, Hiroshi Amano, Shuji Nakamura
English
English (pdf)
Swedish
Swedish (pdf)

Press Release

7 October 2014
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2014 to
Isamu Akasaki
Meijo University, Nagoya, Japan and Nagoya University, Japan
Hiroshi Amano
Nagoya University, Japan
and
Shuji Nakamura
University of California, Santa Barbara, CA, USA
“for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”

New light to illuminate the world

This year’s Nobel Laureates are rewarded for having invented a new energy-efficient and environment-friendly light source – the blue light-emitting diode (LED). In the spirit of Alfred Nobel the Prize rewards an invention of greatest benefit to mankind; using blue LEDs, white light can be created in a new way. With the advent of LED lamps we now have more long-lasting and more efficient alternatives to older light sources.
When Isamu Akasaki, Hiroshi Amano and Shuji Nakamura produced bright blue light beams from their semi-conductors in the early 1990s, they triggered a funda-mental transformation of lighting technology. Red and green diodes had been around for a long time but without blue light, white lamps could not be created. Despite considerable efforts, both in the scientific community and in industry, the blue LED had remained a challenge for three decades.
They succeeded where everyone else had failed. Akasaki worked together with Amano at the University of Nagoya, while Nakamura was employed at Nichia Chemicals, a small company in Tokushima. Their inventions were revolutionary. Incandescent light bulbs lit the 20th century; the 21st century will be lit by LED lamps.
White LED lamps emit a bright white light, are long-lasting and energy-efficient. They are constantly improved, getting more efficient with higher luminous flux (measured in lumen) per unit electrical input power (measured in watt). The most recent record is just over 300 lm/W, which can be compared to 16 for regular light bulbs and close to 70 for fluorescent lamps. As about one fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth’s resources. Materials consumption is also diminished as LEDs last up to 100,000 hours, compared to 1,000 for incandescent bulbs and 10,000 hours for fluorescent lights.
The LED lamp holds great promise for increasing the quality of life for over 1.5 billion people around the world who lack access to electricity grids: due to low power requirements it can be powered by cheap local solar power.
The invention of the blue LED is just twenty years old, but it has already contributed to create white light in an entirely new manner to the benefit of us all.
Read more about this year's prize
Information for the Public
Pdf 1.1 MB
Scientific Background
Pdf 770 kB
To read the text you need Acrobat Reader.

Isamu Akasaki,, Japanese citizen. Born 1929 in Chiran, Japan. Ph.D. 1964 from Nagoya University, Japan. Professor at Meijo University, Nagoya, and Distinguished Professor at Nagoya University, Japan.
Hiroshi Amano,, Japanese citizen. Born 1960 in Hamamatsu, Japan. Ph.D. 1989 from Nagoya University, Japan. Professor at Nagoya University, Japan.
Shuji Nakamura, American citizen. Born 1954 in Ikata, Japan. Ph.D. 1994 from University of Tokushima, Japan. Professor at University of California, Santa Barbara, CA, USA.
Prize amount: SEK 8 million, to be shared equally between the Laureates.
Contact persons: Jessica Balksjö Nannini, Press Officer, Phone +46 8 673 95 44, +46 70 673 96 50, jessica.balksjo@kva.se
Olle Inganäs, member of the Nobel Committee for Physics, +46 13 28 12 31, ois@ifm.liu.se

Nobel Prize® är is a registered trademark of the Nobel Foundation.
This year marks the 275th anniversary of The Royal Swedish Academy of Sciences. The Academy was founded in 1739 and is an independent organization whose overall objective is to promote the sciences and strengthen their influence in society. The Academy takes special responsibility for the natural sciences and mathematics, but endeavours to promote the exchange of ideas between various disciplines.

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The Nobel Prize in Physiology or Medicine 2014


The Nobel Prize in Physiology or Medicine 2014
John O'Keefe, May-Britt Moser, Edvard Moser

The Nobel Prize in Physiology or Medicine 2014 was divided, one half awarded to John O'Keefe, the other half jointly to May-Britt Moser and Edvard I. Moser "for their discoveries of cells that constitute a positioning system in the brain".

John O'Keefe - Facts

John O'Keefe
John O'Keefe
Born: 1939, New York, NY, USA
Affiliation at the time of the award: University College, London, United Kingdom
Prize motivation: "for their discoveries of cells that constitute a positioning system in the brain"
Field: physiology, spatial behavior
Prize share: 1/2

May-Britt Moser - Facts

May-Britt Moser
May-Britt Moser
Born: 1963, Fosnavåg, Norway
Affiliation at the time of the award: Centre for Neural Computation, Trondheim, Norway
Prize motivation: "for their discoveries of cells that constitute a positioning system in the brain"
Field: physiology, spatial behavior
Prize share: 1/4

Edvard Moser - Facts

Edvard I. Moser
Edvard I. Moser
Born: 1962, Ålesund, Norway
Affiliation at the time of the award: Kavli Institute for Systems Neuroscience, Trondheim, Norway
Prize motivation: "for their discoveries of cells that constitute a positioning system in the brain"
Field: physiology, spatial behavior
Prize share: 1/4
 
Press Release
2014-10-06

The Nobel Assembly at Karolinska Institutet has today decided to award

The 2014 Nobel Prize in Physiology or Medicine
with one half to
John O´Keefe
and the other half jointly to
May-Britt Moser and Edvard I. Moser
for their discoveries of cells that constitute a positioning
system in the brain
How do we know where we are? How can we find the way from one place to another? And how can we store this information in such a way that we can immediately find the way the next time we trace the same path? This year´s Nobel Laureates have discovered a positioning system, an “inner GPS” in the brain that makes it possible to orient ourselves in space, demonstrating a cellular basis for higher cognitive function.
In 1971, John O´Keefe discovered the first component of this positioning system. He found that a type of nerve cell in an area of the brain called the hippocampus that was always activated when a rat was at a certain place in a room. Other nerve cells were activated when the rat was at other places. O´Keefe concluded that these “place cells” formed a map of the room.
More than three decades later, in 2005, May-Britt and Edvard Moser discovered another key component of the brain’s positioning system. They identified another type of nerve cell, which they called “grid cells”, that generate a coordinate system and allow for precise positioning and pathfinding. Their subsequent research showed how place and grid cells make it possible to determine position and to navigate.
The discoveries of John O´Keefe, May-Britt Moser and Edvard Moser have solved a problem that has occupied philosophers and scientists for centuries – how does the brain create a map of the space surrounding us and how can we navigate our way through a complex environment?

How do we experience our environment?

The sense of place and the ability to navigate are fundamental to our existence. The sense of place gives a perception of position in the environment. During navigation, it is interlinked with a sense of distance that is based on motion and knowledge of previous positions.
Questions about place and navigation have engaged philosophers and scientists for a long time. More than 200 years ago, the German philosopher Immanuel Kant argued that some mental abilities exist as a priori knowledge, independent of experience. He considered the concept of space as an inbuilt principle of the mind, one through which the world is and must be perceived. With the advent of behavioural psychology in the mid-20th century, these questions could be addressed experimentally. When Edward Tolman examined rats moving through labyrinths, he found that they could learn how to navigate, and proposed that a “cognitive map” formed in the brain allowed them to find their way. But questions still lingered - how would such a map be represented in the brain?

John O´Keefe and the place in space

John O´Keefe was fascinated by the problem of how the brain controls behaviour and decided, in the late 1960s, to attack this question with neurophysiological methods. When recording signals from individual nerve cells in a part of the brain called the hippocampus, in rats moving freely in a room, O’Keefe discovered that certain nerve cells were activated when the animal assumed a particular place in the environment (Figure 1). He could demonstrate that these “place cells” were not merely registering visual input, but were building up an inner map of the environment. O’Keefe concluded that the hippocampus generates numerous maps, represented by the collective activity of place cells that are activated in different environments. Therefore, the memory of an environment can be stored as a specific combination of place cell activities in the hippocampus.

May-Britt and Edvard Moser find the coordinates

May-Britt and Edvard Moser were mapping the connections to the hippocampus in rats moving in a room when they discovered an astonishing pattern of activity in a nearby part of the brain called the entorhinal cortex. Here, certain cells were activated when the rat passed multiple locations arranged in a hexagonal grid (Figure 2). Each of these cells was activated in a unique spatial pattern and collectively these “grid cells” constitute a coordinate system that allows for spatial navigation. Together with other cells of the entorhinal cortex that recognize the direction of the head and the border of the room, they form circuits with the place cells in the hippocampus. This circuitry constitutes a comprehensive positioning system, an inner GPS, in the brain (Figure 3).

A place for maps in the human brain

Recent investigations with brain imaging techniques, as well as studies of patients undergoing neurosurgery, have provided evidence that place and grid cells exist also in humans. In patients with Alzheimer´s disease, the hippocampus and entorhinal cortex are frequently affected at an early stage, and these individuals often lose their way and cannot recognize the environment. Knowledge about the brain´s positioning system may, therefore, help us understand the mechanism underpinning the devastating spatial memory loss that affects people with this disease.
The discovery of the brain’s positioning system represents a paradigm shift in our understanding of how ensembles of specialized cells work together to execute higher cognitive functions. It has opened new avenues for understanding other cognitive processes, such as memory, thinking and planning.


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