In nanophysics one is dealing with physical systems that are formed of parts consisting of a relatively small number of atoms; these systems are typically less than 100 nm in size. As a consequence quantum and surface effects are extremely important. The subject can be traced back to a remarkably visionary and famous talk given […]
Computer science • Condensed matter • Materials • Physics • Quantum physics
When quantum computing comes, it very likely will rely for the fast storage and processing of information on spintronics. Spintronics (from spin transport electronics) is a branch of technology that specifically makes use of quantum-mechanical spin, and especially of the transport of that spin, in electronic devices. Spin is the part of the total angular […]
Quantum mechanics represented a revolution in physics with implications in many other fields like chemistry and biology. It also conducted changes on some of the main scientific lines of thought, including a farewell to determinism. In the science before quantum mechanics probability was accepted only as a lack of knowledge from the system being studied […]
The Penrose–Hameroff theory of orchestrated objective reduction (Orch OR) claims that quantum computations in the brain account for consciousness . The communication among neurons by the secretion of neurotransmitters is based on synaptic vesicles distributed along their axons. The neuronal cytoskeleton has a key role in the dynamics of these vesicles. In the 1990s, Stuart […]
As we have discussed in our previous post, there is an important debate in the scientific community regarding the existence of negative absolute temperatures. The debate is not over, and both sides have valuable arguments, but in any case, one thing has already been proved. If negative absolute temperatures are real, the requirement to achieve […]
Condensed matter • Materials • Physics • Quantum physics • Theoretical physics
At low temperatures, the resistivity of a metal (the inverse of its conductivity) is nearly constant. As the temperature of a material is lowered and as we approach absolute zero the resistivity should approach a constant value. Many metals, known as normal metals, behave in this way. The behaviour of another class of metals and […]
Sunlight is the most important energy source of Earth. All earthlings live thanks to the ability of plants and bacteria to transform solar energy into chemical one. As sunlight is a free, and practically unlimited, energy source it is easy to understand the general interest in finding efficient ways of transforming it into electrical power […]
Almost everyone with basic knowledge of physics have one clear concept, there is a minimum temperature and it is called ‘absolute zero’. This temperature corresponds to -273.15 degrees in the Celsius scale. In the Kelvin or absolute scale it is zero, by definition. Furthermore, there is another idea that is also widespread: absolute zero is […]
Of all the advances made in theoretical physics in the last twenty years, I still have no doubt that the most impressive one is the so called Maldacena’s conjecture, the guess that the physics involved in some models of quantum gravity living in a very concrete 5-dimensional spacetime has a one-to-one correspondence with the physics […]
The second law of thermodynamics is one of the oldest and most tested physical laws. Unfortunately, it prevents us from doing very useful things, like creating a perpetual motion machine of the second kind. This law is extremely important for both theoretical and practical purposes and, because of that, it has been broadly studied since […]