“Everything should be made as simple as possible, but not simpler.”

## Time

**“For us believing physicists, the distinction between past, present and future is only a stubbornly persistent illusion.” – **Albert Einstein

## Quantum Theory: A Very Short Introduction

“I think I can safely say that no one understands quantum mechanics.”

“What has been considered to be the arena of clear and determinate process was found to be at its subatomic roots, cloudy and fitful in its behavior.”

“Compared with this revolutionary change (quantum mechanics) the great discoveries of general and special relativity seem not much more than interesting variations on classical themes.”

“Quarks and gluons are 100 million times smaller than atoms.”

“The manner in which two trains of waves combine depends upon how these oscillations relate to each other.”

“Change of energy is the same as change of frequency.”

“Quantum theory permits the mixing together of two states that would classically be mutually exclusive to each other.”

“Swallow the quantum mechanics theory whole without worrying about the taste or whether you can digest it.”

“We cannot make the mystery go away by explaining how it works.”

“When you have eliminated the impossible, whatever remains must be the case, however improbable it may seem to be.”

“Quantum theory predictions of the results of measurements are statistical in character & not deterministic.”

“Quantum theory deals in probabilities rather than certainties.”

“The behavior one finds depends upon what one chooses to look for.”

“Asking a particle-like question gives you a particle like answer. Asking a wave-like question gives a wave-like answer.”

“The probability interpretation implied that measurements must be occasions of instantaneous and discontinuous change.”

“It is not possible (yet) to simultaneously have perfect knowledge of both position and momentum.”

“One can know where an electron is, but not what it is doing. What can know what an electron is doing but not where it is.”

“What classically were mutually distinct possibilities are tangled with each other quantum mechanically.”

“How can it be that the quantum constituents of the physical world, such as quarks, gluons and electrons, whose behaviors is cloudy and fitful, can give rise to the macroscopic world of everyday experience which seems clear and reliable.”

“Quantum mechanically speaking a particle can borrow energy against time.”

“In quantum mechanics there are no continuously observable trajectories.”

“What people had thought of as empty space (the vacuum) was in fact filled with this sea of negative energy electrons.”

“It had become clear that there is an irreducible degree if non-locality present in the physical world.”

“Instead of saying “observer created reality”, a more accurate term might be “observer-influenced reality.”

“The world is not only stranger than we thought, it is stranger than we could think.”