The elephants in the room
- A fourth fundamental force of nature that quantum theory cannot explain, namely gravity, doesn't even involve particles. None of the decades of effort can bring gravity under the quantum umbrella to explain all of fundamental physics within one "theory of everything."
- Then it appears that over 95 per cent of the universe consists of dark matter and dark energy. There is currently no explanation within the standard model.
MORE IDEAS FROM THE ARTICLE
Quantum mechanics explains the basic mathematical framework that supports it all.
To understand how things work in reality, quantum mechanics must be combined with other elements of physics, such as Einstein's special theory of relativity, to create quantum field theories.
Understanding how electrons move or not through a solid material and so make a material a metal, an insulator or a semiconductor, for example, requires the development of "effective field theories" that don't go into all the details.
But it is difficult to construct such a theory, and the reason why many important questions in solid-state physics remain unresolved.
Quantum particles can act as particles located in a single place, or they can act as waves that are distributed all over space or in several places at once.
How they appear seems to depend on how we choose to measure them. Before we measure, they seem to have no apparent properties at all. This fuzziness leads to paradoxes such as Schrödinger’s cat (a cat is left dead and alive at the same time). Quantum particles also seem to affect one another at the same time even if they are far away from each other, known as entanglement.
Quantum physics is the field of physics that explains how everything works.
It is the best description of the nature of the particles that make up matter and the forces with which they interact. If you want to explain how photons on light turn to electrical current in a solar panel, or how the sun keeps burning, you'll need to use quantum physics.
Three different quantum field theories deal with three of the four fundamental forces by which matter interacts:
- Electromagnetism: It explains how atoms hold together.
- The strong nuclear force: It describes the stability of the nucleus at the centre of the atom.
- The weak nuclear force: It explains why some atoms undergo radioactive decay.
The three theories are known as the "standard model" of particle physics.
RELATED IDEAS
Many insights of Albert Einstein are now part of popular imagination: black holes, time warps, and wormholes show up in movies and books.
Less famous, but probably the most revolutionary part of Einstein's phenomena, is a simple idea that shows how pieces fit together and illuminate the road ahead.
According to physicists, quantum particles are responsible for three forces of nature:
- Strong nuclear force.
- Weak nuclear force.
- Electromagnetic force.
The fourth force of nature, gravity, is till now assumed to not originate from quantum particles, but from the curves in the space-time continuum, according to the celebrated physician Albert Einstein.
The particle célèbre is the muon, which is akin to an electron but far heavier, and is an integral element of the cosmos. Dr. Polly and his colleagues — an international team of 200 physicists from seven countries — found that muons did not behave as predicted when shot through an intense magnetic field at Fermilab.
The aberrant behavior poses a firm challenge to the Standard Model, the suite of equations that enumerates the fundamental particles in the universe (17, at last count) and how they interact.