THE QUANTUM ROBIN

Introduction

A Perplexing property of quantum mechanics could be allowing birds to see and navigate the planet’s magnetic fields. One -fifth of Earth’s 10,000 birds species migrate over great distances, crossing seemingly insurmountable obstacles as they follow the seasons.Demoiselle Cranes fly to altitudes in excess of 20,000 feet as they pass over the Himalayan Mountains . The Arctic Tern travels from pole to pole in pursuit of an endless summer, a distance of some 40,000 miles.

Scientists have long speculated that certain animals are making use of magnetic fields to find their way, but biologists are mystified as to how they might do it. Now some answers might be coming from one of the most perplexing interactions in Physics.

Radical, Spins and Coherence

Despite decades of study, the physics basis of the robin magnetic sense remains elusive. The two main models for Robin magnetoreception are a magnetite-based model and a radical-pair-based model. The former suggests that the compass has its foundation in small particles of magnetite located in the head of the bird. The latter idea is that Robin compass may be produced in a chemical reaction in the eye of bird, involving the production of a radical pair. A radical pair, most generally, is a pair of molecules, each of which have an unpaired electron. If the radical pair is formed so that the spins on the two unpaired electrons in the system are entangled, (i.e. they begin in a singlet or triplet state) and the reaction products are spin- dependent(i.e., there are distinct products for the cases where the radical pair system is in an overall singlet vs. triplet state), then there is an opportunity for an external magnetic field to affect the reaction by modulating the relative orientation of the electron spins.

Robin Magneto reception

First, light – induced electron transfer from one radical-pair- forming molecule to an acceptor molecule creates a radical pair.

Second, the singlet (S) and triplet (T) electron-spin states interconvert owing to the external (Zeeman) and internal (hyperfine) magnetic couplings.

Third, singlet and triplet radical pairs recombine into singlet and triplet products , respectively, which are biologically detectable.

Cryptochrome

Cryptochromes are photoreceptors that regulate entrainment by light of the circadian clock in plants and animals. They also act as integral parts of the central circadian oscillator in animal brains and as receptors controlling photomorphogenesis in response to blue or ultraviolet(UV-A) light in plants. Cryptochrome s are probably the evolutionary descendent of DNA photolyases, which are light- activated DNA-repair enzymes , and are classified into three groups – plant cryptochromes, animal cryptochromes, and CRY-DASH proteins. Cryptochromes and photolyases have similar three-dimensional structures, characterized by an alpha/beta domain and a helical domain. The structure also includes a chromophore, flavin adenine dinucleotide . The FDA- access cavity of the helical domain is the catalytic site of photolyases, and it is predicated also to be important in the mechanism of cryptochromes.

Entanglement

Quantum entanglement dictates that if two electrons are created at the same time, the pair will be “ entangled” so that whatever happens to one particle affects the other otherwise, it would violate fundamental laws of physics. The two particles remain entangled even when separated by vast distances . So if one particle is spin-up, the other must be spin-down, but what’s mind-boggling is that neither will have a spin until they’re measured . That means that not only willyou not know what the spin of the electron is until you measure it, but that the actual act of measuring the spinwill make it spin-up or spin-down. As difficult as entangled is to believe, as well as understand, it is a well established property of quantum mechanics. And some physicists are suggesting that birds and other animals might be using the effect to see and navigate Earth’s magnetic fields . The process could work via light- triggered interactions on a chemical on birds eyes.

Summary

The incoming light would excite two electrons on a molecule in the birds eye, switching one onto a second molecule , but the two would remain entangled even though they are separated. The Earth’s magnetic field would alter the alignment of the electron’s spin and in the process alter the chemical properties of the molecules. Physicists suspect that the reactions would leave varying concentrations of chemicals throughout the eye, possibly creating a picture of our planet’s magnetic field that would allow birds to orient themselves and sense the proper directions; thereby helping them to migrate.

Biophysicists already have their eyes on a few chemicals that might enable the birds to detect entanglement. One such chemical is called cryptochrome. It’s thought that correlated pairs form in cryptochrome in the presence of blue light.

A Group of Physicists from the University of Oxford have proposed that entanglement could last in a bird’s retina for 100 micro seconds , whereas physicists have only been able to make the interaction last for 80 microseconds.

SUBMITTED BY:
Priyalatha .M.
Ramyashri.
Preethi.
Sahana rao L.N.
1st M.Sc.(1st Semester)

REFERENCE:
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NUCLEAR POWER: TICKET TO FUTURE

INTRODUCTION:

NUCLEAR ENERGY:

NUCLEAR ENERGY is the energy in the nucleus, or core of an atom. Atoms make up everything in the universe and are held together with great force.

In a process called fission, atoms are broken apart, and energy is released. Atoms of uranium, a common element that can be mined from the Earth, are used in nuclear reactors.

In fission, a tiny particle called a neutron hits a uranium atom and the atoms splits. This releases more neutrons, and generates a chain reaction. That reaction releases huge amounts of energy.

Nuclear energy is also produced when two atoms joined to become a new atom. This process is called fusion.

EINSTEIN IS THE TITANS IN THE FIELD OF NUCLEAR ENERGY:

Albert Einstein, one of the great scientists the world has ever seen, has revolutionised the history of science. His contribution is the theory of relativity.

One equation from the theory is E=mc^2. In this formula ‘E’ stands for energy, ‘m’ for mass and ‘c’ is the speed of light, which is a constant, and assumed to be the fastest speed possible in the universe. This formula explains how energy is related to mass. It states that energy and matter are interchangeable. He published the special theory of relativity in 1905 and the general theory of relativity in 1916.

GREAT MIND:

It was Enrico Fermi who discovered that when a radio active substance such as uranium is bombarded by neutrons, it produces by products that are not uranium, and are lighter than the original sample.

In 1935, he bombarded uranium which is considered to be element 92 with neutrons, and produced what appeared to be element 93 and 94.

He won the Noble prize in 1938 for his work in radioactivity, and this allowed him to escape from Italy during WORLD WAR II , and settle in the US. He then built the first nuclear reactor, and worked on the Manhattan project. Fermi died in Chicago in 1954. Element 100, fermium, is named in this honour.

NUCLEAR FISSION:

When an atom splits into two parts, it releases energy.  This process is known as fission. An atom contains protons and neutrons in its central nucleus. In fission, the nucleus splits, either through radioactive decay or because it has been bombarded by other sub atomic particles known as neutrons. The resulting pieces have less combined mass than the original nucleus. The missing mass is converted into nuclear energy.

Controlled fission occurs when a very light neutron bombards the nucleus of an atom, breaking it into two smaller, similarly sized nuclei.

The destruction releases a significant amount of energy as much as 200 times that of the neutron that started the procedure- as well as releasing atleast 2 more neutrons. Controlled reactions of this sort are used to release energy within nuclear power plants. Uncontrolled reactions can fuel nuclear weapons.

NUCLEAR FUSION:

It is an atomic reaction in which multiple atoms combine to create a single, more massive atom. The resulting atom has a slightly smaller mass than the sum of the masses of the original atoms. The difference in mass is released in the form of energy during the reaction.

The most common nuclear fusion reaction in the universe, and the one of the most interest to scientists, is the merging of hydrogen nuclei to form helium nuclei. This is the process that occurs in the interiors of stars including the sun.

HIROSHIMA AND NAGASAKI ARE THE GREAT TRAGIDIES IN THE HISTORY OF MANKIND:

By the time the first atomic bomb had been made, Germany had already surrendered. Japan was defeated as well, but would not surrender.

On august 6^th 1945, an atomic bomb named “LITTLE BOY” was dropped on Hiroshima, Japan. The explosion was huge, the city was destroyed, and 80000 people were killed.

The bomb was dropped by a plane. Despite witnessing the terrible destruction of the bomb on Hiroshima, Japan still refused to surrender. 3 days later, on august 9^th 1945, another atomic bomb, nicknamed “FATMAN”, was dropped on Nagasaki, Japan. 40000 people were killed. 6 days after the bombing of Nagasaki, Japan surrendered and WORLD WAR II was over- but with tragic results.

“LITTLE BOY”:

LITTLE BOY was the first nuclear weapon used in war field. It was a gun type weapon, which detonated by firing one mass of uranium down a cylinder into another mass to create a self sustaining nuclear reaction.

The bomb itself was relatively small despite its huge explosive capability. The heat created was so great that clothes caught fire on people over 2kms from the centre of explosion.

Little boy also created ultra high pressure. The wind speed on the ground directly beneath the explosion was so high, that barely any buildings were left standing.

Radiation poisoning killed many people in the city. Nearly all the people who survived the bomb blast, but lived within 800m of it, died within 30 days. Death from radiation exposure continued for many years.

NUCLEAR REACTORS:

The nuclear reactor is an apparatus in which nuclear fission chain reactions are initiated, controlled, and sustained at a controlled rate. Nuclear power comes from heat that is generated during nuclear fission, when one atom splits into two. Most nuclear power plants use enriched uranium and plutonium as fuel.

Inside a nuclear reactor, there are several rods of uranium. The uranium is used to boil water and produce steam. The steam drives turbines that produce electricity. Rods of graphite’s are used to control the nuclear reaction within the uranium. To put it in an nutshell, in a nuclear reactor, the heat that is given off from the reaction is used to heat water, which creates steam, which drives the turbine, which spins a generator to produce power.

OTHER APPLICATIONS OF NUCLEAR ENERGY:

• Industries use Radioisotopes to develop highly sensitive gauges to measure the thickness and density of many materials. It also uses radioisotopes as imaging devices to inspect finished goods for weakness and flaws.
• Radionuclide’s are used in medicine; where the radioisotope of iodine, gallium, thallium etc. are used for medical diagnostic procedures
• Radioisotopes are used to battle cancer.
• Nuclear powered vehicles.

NUCLEAR INDIA:

India entered the nuclear age in 1948, when the Atomic Energy Commission was established with Dr. Homi Bhabha as a chairman. India’s first research nuclear reactor and its first nuclear power plant were built with assistance from Canada. By 1963, India had 2 research reactors and 4 nuclear power reactors.

The next milestone was on May 18^th 1974 when India conducted a peaceful nuclear explosion. More nuclear power reactors were built, without anyone foreign collaboration, and on may 11^th and 13^th 1998 India successfully exploded both fission and fusion devices.

In order to meet its nuclear energy requirements, India has signed agreements with a host of countries to obtain uranium for its nuclear power plants. The future of nuclear co operation for India with various countries is bright, as India tried hard to increase its nuclear power output.

“BARC”:

Baba Atomic research centre [ BARC ] is India’s premiere nuclear research institute based in Trombay, Mumbai. It is named after India’s renowned nuclear scientist Dr. Homi J Bhabha. BARC conducts researches to sustain peaceful applications of nuclear energy mainly for power generation. Besides that BARC operates a number of research reactors across the country.

NUCLEAR WASTE:

Nuclear wastes are radioactive wastes that are by products of nuclear power generation. Radioactive wastes can be high level, middle level and low level. Radioactive waste is produced by a number of sources, but by far the largest quantities are generated by the nuclear power plants, and nuclear weapons production industries.

One of the major problems associated with radioactive wastes is the fact that it will require isolation from the human environment for 100s of years.

EFFECTS OF NUCLEAR ENERGY TO THE ENVIRONMENT:

Nuclear energy is “clean energy” in the sense that it does not cause air pollution. However, the mining, enrichment, and transportation of uranium for nuclear energy cause some degree of harm to the environment.

Nuclear power plants use large quantities of water for steam production and cooling, for which large quantities of water from a lake or river are required. This should affect fish, and other aquatic life. The waste material produced by nuclear plants is dangerously radioactive, and should never be allowed to escape into the environment.

BOON OR BANE????

The need for new sources of energy is increasing day by day, because existing energy resources are getting rapidly used up. But, nothing to worry. Science has already identified an evergreen spring of POWER- NUCLEAR ENERGY. It’s the largest source of energy that man has ever found.

However, though nuclear energy has wide uses, it also has sadly, the power to destroy everything. The world still remembers the booms that devastated Hiroshima and Nagasaki. The disasters at nuclear power plants have also added to the fear of nuclear energy...

SUBMITTED BY:

Nirmal Mathew

Nithya K Nair

Poojashree V Rai

Prajna P S

Pramitha A

1st M.Sc {1st Semester}

     

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