Gauge theories are important as the successful field theories explaining the dynamics of elementary particles . Quantum electrodynamics is an abelian gauge theory with the symmetry group U(1) and has one gauge field, the electromagnetic four-potential , with the photon being the gauge boson. The Standard Model is a non-abelian gauge theory with the symmetry group U(1) × SU(2) × SU(3) and has a total of twelve gauge bosons: the photon , three weak bosons and eight gluons .
The first step towards the Standard Model was Sheldon Glashow 's discovery in 1961 of a way to combine the electromagnetic and weak interactions .  In 1967 Steven Weinberg  and Abdus Salam  incorporated the Higgs mechanism    into Glashow's electroweak interaction , giving it its modern form.
Bora Bora: enjoy paradise.
This heavenly island of French Polynesia is a place of dreams, where tourists are hypnotized by clear blue lagoons, white sand beaches, breathtaking landscapes, sapphire blue skies, and glamorous resorts.
Best time for vacation.
As any tropical island, Bora Bora has two seasons rather than four. There is dry season and rainy season. The weather is warm for the whole year round in Bora Bora.
High season runs from May to October plus Christmas weeks. From May through October no rain showers occur and air temperature ranges from 67 F to 85 F there. High season sees mad rush of tourists, so all Bora Bora resorts have their peak rates during this period. April and May are considered to be the best months to visit Bora Bora. You will get low-season hotel rates and still nice weather.
Off-season lasts from November to March there. The weather is slightly hotter as well as greatly wetter. If high humidity doesn't bother you or if you want to avoid crowds of tourists then low season is the best time to visit this wonderful island.
Greatest things to do.
Bora Bora offers a lot of things to every vacationer whether active or inactive he or she wishes to be. There are many lagoon and water excursions as well as underwater activities and aerial sightseeing tours to explore captivating beauty of the island. You may also discover hiking tracks of Bora Bora or take jeep safari. If you just want to relax then SPA treatments are right choice for you.
The most popular and breathtaking water activities are: snorkel safari, scuba diving, windsurfing, waterskiing, parasailing, sunset cruises, aqua safari, kite surfing, underwater scooter excursions, lagoon fishing, and glass bottom boat tours. If you want to parasail you will enjoy view of Bora Bora from your own parachute over turquoise water. Private helicopter tour gives you a chance to fly over the island and enjoy amazing aerial views.
Bora Bora award-winning spa and healing centers offer to restore your body and mind. Some spa centers have glass floors for their visitors to admire marine creatures during treatments. And others enable vacationers to enjoy ocean or lagoon views. Natural ingredients such as coconut, vanilla, marine mud, seaweed, and frangipani are used during spa treatments.
Before booking tickets mind that Bora Bora is very expensive. The average price for overwater bungalow is close to 1000 USD per night during high season. If you want to save money you may visit Bora Bora in shoulder or low season. A lot of resorts offer discounts for those who book at least a month in advance, so reservation is essential.