Partical Physics

                                                        PARTICAL PHYSICS

 The first pillar is quantum field theory. Which describes  that everything is field . This theory proposed the field quanta  necessarily the chunked ripples in a field that  look like particle.
A boost to Quantum Field Theory  came with   Dirac Equation , a single particle equation which obeying both relativity and  quantum mechanics . but this  theory had some difficulties . to overcome these difficulties in 1940, An Gauge theory became produced.  Which is known as the Standard Model of Particle Physics.
This model predict that Electromagnetic  force is caused b/w two electrons by an  exchange of Photons , Weak nuclear force    by exchange of Bosons(W-, W+, Z) AND Strong Nuclear forces by 8 gluons.
And for gravity this theory assumed that Graviton particle appears.
The guiding principal of the standard model is that  its equations  are Symmetrical . All Other  equations related to this  are also Symmetrical  .
These Symmetries beget forces that are carried by special particles called bosons.
Physicists want to unify the Strong , Weak  Nuclear Force and Electromagnetic Force.
Later the theory of ELECTROWEAK FORCES  as formulated  by Sheldon Glashow , Steven Weinberg and Abdus Slam , who won the 1979  Nobel Prize in physics   for their efforts .
The Weak Force , which is involved in radioactive beta decay   , does not act  on all  the quarks and  leptons . Each  of these particles  comes in mirror –image varieties , termed left-handed and right-handed  , and the Beta decay Force acts only on the left-handed ones a striking fact still unexplained  50 years  after its discovery. The family symmetry  among the left-handed particles  helps to define the electroweak theory.
In the initial stages , the theory had two essential   shortcomings . First  , It foresaw four long-range force particles –referred to as gauge  bosons where as  nature has but one : the photon.

The Other three have a short range less than about 10 root -17  meter. According to Heisenberg’s Uncertainty Principle , this limited range implies that the force particles must have a mass approaching 100 billon electron volts (Gev).
The second shortcoming is that the family  symmetry does not permit masses for the quarks and leptons , yet these particles do have masses.
So we need to recognize that  a symmetry  of the laws  of nature need not be  reflected  into the outcome  of those laws.
Physicists Says “that the Symmetry is Broken”.
Later the inspiration came from a seemingly unrelated phenomena : SuperConductivity , in Which certain  materials carry electric current with zero resistance  at   low temperatures . although the laws of electromagnetism themselves material is not.  A photon  gains mass within  a superconductor.  Thereby limiting  the intrusion of magnetic fields into the material .
This problem is a perfect prototype for the electroweak  theory . If Space  is filled with a   type of superconductor  that affects the weak interaction rather than electromagnetism, it gives mass to the W and Z bosons and limits the range of  weak   interactions.

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