Casimir Effect

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The Casimir -polder force and the Casimir effects in quantum physics theory are the physical forces arising from the quantized field. They were named after Hendrik Casimir who was a Dutch physicist, he predicted them in 1948. We can use the idea of conducting metals and dielectrics alters the vacuum expectation values of the energy of second quantized electromagnetic for understanding this process. The value of the energy depends on the size and shape and position of the dielectrics and the conductors, this effect manifests itself as a force between two objects. The Analogue of the Casimir effect needs any medium supporting oscillation. 


Casimir Effect Experiment

The Casimir effect is said to be an attractive force that acts between two parallel, uncharged, closely placed, metallic plates in a vacuum. In 1948 this phenomenon was predicted theoretically. It is reliably investigated and is experimented in recent years itself. The Casimir effect is in fact said to be familiar with the van der Waal forces in case of very separation, when the relativistic effects come into force. Reviewing the experiment on measuring the Casimir force by means of an atomic force microscope, micromechanical torsional, and torsion pendulum. To the thermal Casimir force, special attention is paid. We discuss the role of the Casimir effect in the nanosystem which involves the stiction phenomenon, the interaction of carbon atoms with hydrogen nanotubes, and actuators. These contrasting predictions of an extra-dimensional unification scheme and the other physics beyond the standard model are also considered in the application of the Casimir effect. 


Casimir Physics 

As discussed earlier, the Casimir effect is described by quantum field theory, which says that all the fundamental fields, e.g. electromagnetic fields, must be quantized at each and every point in space. If we look at the more simplified views- fields in physics may be looked as if space was filled with interconnected vibrating springs and balls, whereas the strength of the field is looked at as displacing a ball from its rest position. The propagating vibrations in this field are governed by the appropriate wave equations. The other quantization of quantum physics theory requires that each ball and spring is combined should be quantized, that is the field strength be quantized at each point in the space. Most of the time the field in the space is simple harmonic oscillation and its quantization places quantum harmonic oscillations. When the field corresponds to elementary particles of particle physics. However, even if the vacuum has a most complex structure all calculations of the quantum physics theory must be made in relation to the model of vacuum. The vacuum has all the properties that the particle must have like polarization in case of light, spinning, energy, and so on. 

On average most of these particles get canceled out. 


History of Casimir Effect

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Hendrik Casimir a dutch physicist and Dirk polder at the Phillips research labs, both proposed the existence of a force between two polarizable atoms or between such atoms and a conducting plate in the year 1947. This special form of force is known as the Casimir-Polder force. Neil Bohor suggested that something is to do with the zero-point energy, Casimir all alone predicted and formulated the theory that states that a force between neutral conducting plates in 1948 is known as the Casimir effect which is said in the narrow sense. These predictions which were made regarding the force were later extended to finite conductivity metals, but the recent calculation suggests more general geometry. 

The experiments which were done before 1997, had observed the force qualitative and the indirect violations predicted that Casimir's energy had been made by measuring the thickness of liquid helium. Until 1997, a direct experiment was done by S.Lamoreaux measuring the force within 5% of the values predicted by the theories. This experiment approached the accuracy of a few percent. 


Applications of Casimir Force

A truly scaling discovery was made by Casimir in the year 1948, that the zero-point fluctuations can lead to physical effects on the microscopic systems. This idea has been applied to a great number of fields like chromodynamics. Casimir field has even found a maritime application in the determination of the attractive forces which are present between the two ships, in a sea owning a modification of wave structure between the ships in the sea. Another application of it is found in nanotechnology also. It's unclear that this force will be in general a nuisance or a very useful feature in the nanoengineering field. It is said like this because the force is a very non-linear force. The weekly coupling mechanical oscillations can be imagined by using Casimir's effect. 

The nanoengineering while writing this uses remains speculative. Casimir’s repulsive force is created by the use of magnetic materials. 

FAQ (Frequently Asked Questions)

Q1. What is the Working of the Casimir Effect?

Ans: A small attractive force which is known as the Casimir effect acts between two very parallel uncharged conducting plates. This happens due to the quantum vacuum fluctuation of the electromagnetic field. As the plates are moving closer the energy density decreases. Which proves that there is a very small force that is attracting them.

Q2. Does Zero-point Energy Exist in the Casimir Effect?

Ans: This energy which is known as the zero-point energy is harnessed in the traditional manner. The zero-point energy depicts that, there is a finite minimum amount of motion in even absolute zero and all matters. 

Q3. The Casimir Predict would Happen with the Plate?

Ans: This vacuum was first predicted by the Dutch physicist whose name was Hendrik Casimir in the year 1948. It was proved that if the plates and the material between them which is generally a liquid have particular dielectrics permittivities then the force between the two plates will become negative.

Q4. What is the Energy in the Vacuum?

Ans: It is underlying background energy that exists throughout the entire universe in space.  Still, the exact effect of the vacuums which are fleeting bits of energy is difficult to quantify. This energy of the vacuum is a very special case of the zero-point energy that releases to quantum vacuum.