physics
TRANSCRIPT
Physics
Project
2. God’s Particle/Higgs-Boson
1. Newton laws of motion
BACKGROUND
Sir Isaac Newton (1643-1727) an English scientist and mathematician famous for his discovery of the law of gravity also discovered the three laws of motion. He published them in his book Philosophiae Naturalis Principia Mathematica (mathematic principles of natural philosophy) in 1687. Today these laws are known as Newton’s Laws of Motion and describe the motion of all objects on the scale we experience in our everyday lives.
THE NEWTON’S 3 LAWS OF MOTION ARE AS FOLLOWS:-
1. EVERY BODY CONTINUES TO REMAIN IN A STATE OF REST OR OF UNIFORM MOTION UNLESS IT IS ACTED UPON BY EXTERNAL UNBALANCED FORCE.
2. The rate of change in momentum is directly proportional to the external unbalanced force applied.
3.To every action there is always an equal and opposite reaction.
•In outer space, away from gravity and any sources of friction, a rocket ship launched with a certain speed and direction would keep going in that same direction and at that same speed forever.
What does this mean?Basically, an object will “keep doing what it was doing” unless acted on by an unbalanced force.
If the object was sitting still, it will remain stationary. If it was moving at a constant velocity, it will keep moving.
It takes force to change the motion of an object.
What is meant by unbalanced force?
If the forces on an object are equal and opposite, they are said to be balanced, and the object experiences no change in motion. If they are not equal and opposite, then the forces are unbalanced and the motion of the object changes.
SOME EXAMPLES FROM REAL LIFE
A soccer ball is sitting at rest. It takes an unbalanced force of a kick to change its motion.
Two teams are playing tug of war. They are both exerting equal force on the rope in opposite directions. This balanced force results in no change of motion.
NEWTON’S FIRST LAW IS ALSO CALLED THE LAW OF INERTIA
Inertia: the tendency of an object to resist changes in its state of
motion
The First Law states that all objects have inertia. The more mass an object has, the more inertia it has (and the harder it is to change
its motion).
Things don’t keep moving forever because there’s almost always an unbalanced force acting upon it.
A book sliding across a table slows down and stops because of the force of friction.
If you throw a ball upwards it will eventually slow down and fall because of the force of gravity.
WHAT DOES F = MA MEAN?
Force is directly proportional to mass and acceleration. Imagine a ball of a certain mass moving at a certain acceleration. This ball has a certain force.
Now imagine we make the ball twice as big (double the mass) but keep the acceleration constant. F = ma says that this new ball has twice the force of the old ball.
Now imagine the original ball moving at twice the original acceleration. F = ma says that the ball will again have twice the force of the ball at the original acceleration.
MORE ABOUT F = MA
If you double the mass, you double the force. If you double the acceleration, you double the
force.
What if you double the mass and the acceleration?
(2m)(2a) = 4F
Doubling the mass and the acceleration quadruples the force.
So . . . what if you decrease the mass by half? How much force would the object have now?
WHAT DOES F = MA SAY?F = ma basically means that the force of an object comes from its mass and its
acceleration.
Something very small (low mass) that’s changing speed very quickly (high acceleration), like a bullet, can still have a great force. Something very small changing speed very slowly will have a very weak force.
Something very massive (high mass) that’s changing speed very slowly (low acceleration), like a glacier, can still have great force.
WHAT DOES THIS MEAN?
For every force acting on an object, there is an equal force acting in the opposite direction. Right now, gravity is pulling you down in your seat, but Newton’s Third Law says your seat is pushing up against you with equal force. This is why you are not moving. There is a balanced force acting on you– gravity pulling down, your seat pushing up.
VOCABULARYInertia:
the tendency of an object to resist changes in its state of motion
Acceleration:
•a change in velocity
•a measurement of how quickly an object is changing speed, direction or both
Velocity:The rate of change of a
position along a straight line with respect to time Force:
strength or energy
GOD PARTICLE
/ HIGGS
BOSON
The Higgs boson or Higgs particle is a proposed elementary particle in the Standard Model of particle physics. The Higgs boson's existence would have profound importance in particle physics because it would prove the existence of the hypothetical Higgs field—the simplest of several proposed mechanisms for the breaking of electroweak symmetry, and the means by which elementary particles acquire mass . The leading explanation is that a field exists that has non-zero strength everywhere—even in otherwise empty space—and that particles acquire mass when interacting with this so-called Higgs field. If this theory is true, a matching particle—the smallest possible excitation of the Higgs field—should also exist and be detectable, providing a crucial test of the theory. Consequently, it has been the target of a long search in particle physics.
What is Higgs Boson?
Higgs boson
One possible signature of a Higgs boson from a simulated collision between two protons. It decays almost immediately into two jets of hadrons and two
electrons, visible as lines.[Note 1]
Composition Elementary particleStatistics Bosonic
Status
Tentatively observed – a boson "consistent with" the Higgs boson has been observed, but as of August 2012, scientists have not conclusively identified it as the Higgs boson.
Symbol H0
TheorizedR. Brout, F. Englert, P. Higgs, G. S. Guralnik, C. R. Hagen, and T. W. B. Kibble (1964)
DiscoveredTentatively announced July 4, 2012 (see above), by the ATLAS and CMS teams at the Large Hadron Collider
Types 1 in the Standard Model;5 or more in super symmetric models
Mass125.3 ± 0.4 (stat) ± 0.5 (sys) GeV/c2,126 ± 0.4 (stat) ± 0.4 (sys) GeV/c2
Mean lifetime 1.56×10−22 SecondElectric charge 0
HIGGSBOSON
The Higgs boson is named for Peter Higgs who, along with two other teams, proposed the mechanism that suggested such a particle in 1964 and was the only one to explicitly predict the massive particle and identify some of its theoretical properties. In mainstream media it is often referred to as "the God particle", after the title of Leon Lederman's book on the topic(1993). Although the particle is both important and extremely difficult to prove, the epithet is strongly disliked by many physicists, who regard it as inappropriatesensationalism since the particle has nothing to do with God nor any mystical associations, and because the term is misleading: the crucial focus of study is to learn how the symmetry breaking mechanism takes place in nature — the search for the boson is part of, and a key step towards, this goal.
Who Discovered ‘IT’?
INDIAN LINK WITH HIGGS BOSON…Despite the fact that Bose had little direct involvement in theorizing the Higgs boson itself, in India the lack of attention given to one of their own was seen as an insult too big to ignore.
Satyendranath Bose
The boson is named in honor of the Kolkata-born scientist's work in the 1920s with Albert Einstein in defining one of two basic classes of subatomic particles. The work describes subatomic particles that carry force and can occupy the same space if in the same state – such as in a laser beam. All particles that follow such behavior, including the Higgs as well as photons, gravitons and others, are called bosons. Higgs, the English physicist, and others proposed the Higgs boson's existence in 1964 to explain what might give shape and size to all matter. Laymen and the media sometimes call it the "God particle" because its existence is key to understanding the early evolution of the universe. By then, Bose was living in his Indian city of Kolkata after 25 years running the physics department at Dacca University, in what is now Bangladesh. Bose died aged 80 in 1974. The Nobel is not awarded posthumously.
It was Indian physicist Satyendranath Nath Bose after whom class of subatomic particles 'Boson' is named. The elusive Higgs Boson is one of the Bosons.
ProductionA Higgs particle can be produced in a particle collider by taking two particles smashing them together at very high energies. The exact process depends on the details of the particles used and the energy at which they are collided. But in any case the probability of producing a Higgs boson in any collision is always expected to be very small with only 1 Higgs boson being produced per 10 billion collisions. The most common processes are the following : •Gluon fusion. If the collided particles are hadrons such as the proton or antiproton—as is the case in the LHC and Tevatron—then it's most likely that two of the gluons binding the hadron together collide. The easiest way to produce a Higgs particle is if the two gluons combine to form a loop ofvirtual quarks. Since the coupling of particles to the Higgs boson is proportional to their mass, this process is more likely for heavy particles. In practice it is enough to consider the contributions of virtual top and bottom quarks (the heaviest quarks). This process is the dominant contribution at the LHC and Tevatron being about ten times more likely than any of the other processes.
•Higgs Strahlung. If an elementary fermion collides with an anti- fermion—e.g. a quark with an anti-quark or an electron with a positron—the two can merge to form a virtual W or Z boson which, if it carries sufficient energy, can then emit a Higgs boson. This process was the dominant production mode at the LEP, where an electron and a positron collided to form a virtual Z boson, and it was the second largest contribution for Higgs production at the Tevatron. At the LHC this process is only the third largest, because the LHC collides protons with protons, making a quark- antiquark collision less likely than at the Tevatron.
•Weak boson fusion. Another possibility when two (anti-)fermions collide is that the two exchange a virtual W or Z boson, which emits a Higgs boson. The colliding fermions do not need to be the same type. So, for example, an up quark may exchange a Z boson with an anti-down quark. This process is the second most important for the production of Higgs particle at the LHC and LEP.
Top fusion. The final process that is commonly considered is by far the least likely (by two orders of magnitude). This process involves two colliding gluons, which each decay into a heavy quark- antiquark pair. A quark and anti-quark from each
pair can then combine to form a Higgs particle
Thank
YouDiksha Fule
MADE BY,
“If I have ever made any valuable discoveries, it has been owing more to patient attention, than to any other talent.”
-Sir Isaac Newton