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I. Explain the meanings of the words in bold. Use them in sentences of your own.

II. Read the text and decide if the following statements are true or false:

Quantum Electrodynamics describes how light and electromagnetic field interact.

1. Emergence of infinities makes computations meaningless.
2. Feynman's mathematical technique, based on his diagrams, initially seemed very different from approach of Schwinger and Tomonaga.
3. The first formulation of a quantum theory describing radiation and matter interaction is due to Werner Heisenberg.
4. QED achieves agreement between Theory of relativity and Quantum mechanics.
5. Dirac introduced the concept of creation and annihilation operators of particles.
6. Quantum chromodynamics was a subsequent theory to QED.
7. Renormalization allows the infinities get absorbed in constants and yield a finite result.

III. Read the text and answer the following questions:

1. What does quantum electrodynamics describe?
2. Why did R.Feynman call it “the jewel of Physics”?
3. What is the contribution of Paul Dirac to QED?
4. Why did the incompatibility between theory of relativity and quantum mechanics exist?
5. How did Hans Bethe solve the problem of infinities?
6. What is renormalisation?
7. Why did renormalisation become one of the fundamental aspects of QED?

IV. Translate the following sentences paying attention to the Non-Finite forms of the verb:

1. The first formulation of a quantum theory describing radiation and matter interaction is due to Paul Adrien Maurice Dirac.
2. Feynman's mathematical technique, based on his diagrams, initially seemed very different from the field-theoretic, operator-based approach of Schwinger and Tomonaga.
3. Infinities emerged, making such computations meaningless and casting serious doubts on the internal consistency of the theory itself.
4. The idea was simply to attach infinities to corrections at mass and charge that were actually fixed to a finite value by experiments.
5. Renormalization was the need to attach a physical meaning at certain divergences appearing in the theory through integrals.
6. Being extremely accurate in predicting the quantities, QED has been called “the jewel of physics”.
7. Physicists came to believe that to perform any computation for any physical process involving photons and charged particles would be impossible.
8. Feynman was never entirely comfortable with its mathematical validity, even referring to renormalization as a "shell game" and "hocus pocus”.

V. Translate the following sentences from Russian into English. Use the words from the text.