Alain Haché is an experimental

Experimental physics

Within the field of physics, experimental physics is the category of disciplines and sub-disciplines concerned with the observation of physical phenomena in order to gather data about the universe...

 physicist

Physicist

A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

, a professor

Professor

A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...

 at the University of Moncton

Université de Moncton

The Université de Moncton is a French language university located in Moncton, New Brunswick serving the Acadian community of Atlantic Canada...

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. Since 2003 he holds the Canada Research Chair in Photonics

Photonics

The science of photonics includes the generation, emission, transmission, modulation, signal processing, switching, amplification, detection and sensing of light. The term photonics thereby emphasizes that photons are neither particles nor waves — they are different in that they have both particle...

. He is also the author of The Physics of Hockey, a popular science

Popular science

Popular science, sometimes called literature of science, is interpretation of science intended for a general audience. While science journalism focuses on recent scientific developments, popular science is broad-ranging, often written by scientists as well as journalists, and is presented in many...

 book on ice hockey

Ice hockey

Ice hockey, often referred to as hockey, is a team sport played on ice, in which skaters use wooden or composite sticks to shoot a hard rubber puck into their opponent's net. The game is played between two teams of six players each. Five members of each team skate up and down the ice trying to take...

.

In 2002, he and undergraduate student Louis Poirier transmitted faster-than-light

Faster-than-light

Faster-than-light communications and travel refer to the propagation of information or matter faster than the speed of light....

 electrical pulses through a 120-metre long "photonic crystal

Photonic crystal

Photonic crystals are periodic optical nanostructures that are designed to affect the motion of photons in a similar way that periodicity of a semiconductor crystal affects the motion of electrons...

" made of coaxial cable

Coaxial cable

Coaxial cable, or coax, has an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by a tubular conducting shield. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis...

s of alternating characteristic impedance

Characteristic impedance

The characteristic impedance or surge impedance of a uniform transmission line, usually written Z_0, is the ratio of the amplitudes of a single pair of voltage and current waves propagating along the line in the absence of reflections. The SI unit of characteristic impedance is the ohm...

 (12 pairs of 50 Ω

Ohm

The ohm is the SI unit of electrical resistance, named after German physicist Georg Simon Ohm.- Definition :The ohm is defined as a resistance between two points of a conductor when a constant potential difference of 1 volt, applied to these points, produces in the conductor a current of 1 ampere,...

 and 75 Ω cables). The experiment showed that the pulse envelope was recreated at the end of the cables at a speed of >3 c

Speed of light

The speed of light in vacuum, usually denoted by c, is a physical constant important in many areas of physics. Its value is 299,792,458 metres per second, a figure that is exact since the length of the metre is defined from this constant and the international standard for time...

. Since this speed represents the group velocity

Group velocity

The group velocity of a wave is the velocity with which the overall shape of the wave's amplitudes — known as the modulation or envelope of the wave — propagates through space....

 but not the signal velocity

Signal velocity

The signal velocity is the speed at which a wave carries information. It describes how quickly a message can be communicated between two separated parties...

, no energy or information was actually traveling faster than light.

External links

• Alain Haché's webpage @ Université de Moncton
• Alain Haché's scientific contributions @ Google Docs