A study recently published in the journal Nanophotonics reveals that by rapidly modulating the refractive index – which is the ratio of the speed of electromagnetic radiation in a medium compared to its speed in a vacuum – it’s possible to produce photonic time crystals (PTCs) in the near-visible part of the spectrum.
The study’s authors suggest that the ability to sustain PTCs in the optical domain could have profound implications for the science of light, enabling truly disruptive applications in the future.
PTCs, materials in which the refractive index rises and falls rapidly in time, are the temporal equivalent of photonic crystals in which the refractive index oscillates periodically in space causing, for example, the iridescence of precious minerals and insect wings.
Just like a gecko that regrows a broken tail, our peripheral nervous system knows how to regenerate the branches of its cells after an injury. Unfortunately, the cells in our central nervous system—our brain and spinal cord—are far more limited when it comes to regeneration.
Accordingly, diseases that lead to the degeneration and death of brain neurons, such as Alzheimer’s, Parkinson’s and ALS, are irreversible and incurable. So, what is it about the peripheral nervous system, which connects our brain and spinal cord to the other organs, that gives it the power to regenerate itself so readily?
In a new study, researchers at the Weizmann Institute of Science have discovered that a protein, previously known to be expressed only during embryonic development, plays a key role in regenerating adult neurons in the peripheral nervous system.
(RQM) is the most recent among the interpretations of quantum mechanics which are most discussed today. It was introduced in 1996, with quantum gravity as a remote motivation (Rovelli 1996); interests in it has slowly but steadily grown only in the last decades. RQM is essentially a refinement of the textbook “Copenhagen” interpretation, where the role of the Copenhagen observer is not limited to the classical world, but can instead be assumed by any physical system. RQM rejects an ontic construal of the wave function (more in general, of the quantum state): the wave function or the quantum state play only an auxiliary role, akin to the Hamilton-Jacobi function of classical mechanics. This does not imply the rejection of an ontological commitment: RQM is based on an ontology given by physical systems described by physical variables, as in classical mechanics. The difference with classical mechanics is that (a) variables take value only at interactions and (b) the values they take are only relative to the (other) system affected by the interaction. Here “relative” is in the same sense in which velocity is a property of a system relative to another system in classical mechanics. The world is therefore described by RQM as an evolving network of sparse relative events, described by punctual relative values of physical variables.
The physical assumption at the basis of RQM is the following postulate: The probability distribution for (future) values of variables relative to S ′ S′[/sup depend on (past) values of variables relative to S′[/sup but not on (past) values of variables relative to another system S″.
We are about to leap into the age of quantum computing and possibly our technological capabilities will evolve rapidly as a result.
Does this mean we are on the threshold of developing a Type 2 civilization? If so, we should soon be able to make first contact with other intelligent life forms and slowly conquer space.
Astronomers may have discovered the first evidence of heavy black hole “seeds” in the early universe.
These so-called seeds could help explain how some supermassive black holes with masses equivalent to millions, or even billions, times that of the sun could have grown quickly enough to exist less than 1 billion years after the Big Bang.
Potentially, heavy black hole seeds are black holes with masses around 40 million time that of our sun. They are believed to form from the direct collapse of a massive cloud of gas, unlike your typical black hole that’s born when a massive star reaches the end of its life and collapses under its own gravity. Galaxies theorized to host such heavy black hole seeds are referred to as Outsize Black Hole Galaxies (OBGs).
Researchers have a new way to connect quantum devices over long distances, a necessary step toward allowing the technology to play a role in future communications systems.
While today’s classical data signals can get amplified across a city or an ocean, quantum signals cannot. They must be repeated in intervals—that is, stopped, copied and passed on by specialized machines called quantum repeaters. Many experts believe these quantum repeaters will play a key role in future communication networks, allowing enhanced security and enabling connections between remote quantum computers.
A new Princeton study titled “Indistinguishable telecom band photons from a single erbium ion in the solid state” and published Aug. 30 in Nature, details the basis for a new approach to building quantum repeaters. It sends telecom-ready light emitted from a single ion implanted in a crystal. The effort was many years in the making, according to Jeff Thompson, the study’s principal author. The work combined advances in photonic design and materials science.
These all-purpose, desktop machines can reproduce a seemingly infinite variety of items. In fact, they are like miniature factories. In appearance, they resemble a combined washing machine/microwave oven. Raw materials are purchased separately and can be loaded in solid, liquid or powder form. An interior compartment is accessed via a small hatch, where objects are constructed atom-by-atom. The process takes a matter of minutes and the assembled items can be used immediately. New schematics can be accessed from the web and programmed into the machine.
I did not create this animation video and i do not gain any profit from it. This is for educational purposes only.
A molecular assembler, as defined by K. Eric Drexler, is a “proposed device able to guide chemical reactions by positioning reactive molecules with atomic precision”. A molecular assembler is a kind of molecular machine. Some biological molecules such as ribosomes fit this definition. This is because they receive instructions from messenger RNA and then assemble specific sequences of amino acids to construct protein molecules. However, the term “molecular assembler” usually refers to theoretical human-made devices.
Beginning in 2007, the British Engineering and Physical Sciences Research Council has funded development of ribosome-like molecular assemblers. Clearly, molecular assemblers are possible in this limited sense. A technology roadmap project, led by the Battelle Memorial Institute and hosted by several U.S. National Laboratories has explored a range of atomically precise fabrication technologies, including both early-generation and longer-term prospects for programmable molecular assembly; the report was released in December, 2007. In 2008 the Engineering and Physical Sciences Research Council provided funding of 1.5 million pounds over six years for research working towards mechanized mechanosynthesis, in partnership with the Institute for Molecular Manufacturing, amongst others. Likewise, the term “molecular assembler” has been used in science fiction and popular culture to refer to a wide range of fantastic atom-manipulating nanomachines, many of which may be physically impossible in reality. Much of the controversy regarding “molecular assemblers” results from the confusion in the use of the name for both technical concepts and popular fantasies. In 1992, Drexler introduced the related but better-understood term “molecular manufacturing”, which he defined as the programmed “chemical synthesis of complex structures by mechanically positioning reactive molecules, not by manipulating individual atoms”.This article mostly discusses “molecular assemblers” in the popular sense. These include hypothetical machines that manipulate individual atoms and machines with organism-like self-replicating abilities, mobility, ability to consume food, and so forth. These are quite different from devices that merely (as defined above) “guide chemical reactions by positioning reactive molecules with atomic precision”. Because synthetic molecular assemblers have never been constructed and because of the confusion regarding the meaning of the term, there has been much controversy as to whether “molecular assemblers” are possible or simply science fiction. Confusion and controversy also stem from their classification as nanotechnology, which is an active area of laboratory research which has already been applied to the production of real products; however, there had been, until recently, no research efforts into the actual construction of “molecular assemblers”. Nonetheless, a 2013 paper by David Leigh’s group, published in the journal Science, details a new method of synthesizing a peptide in a sequence-specific manner by using an artificial molecular machine that is guided by a molecular strand. This functions in the same way as a ribosome building proteins by assembling amino acids according to a messenger RNA blueprint. The structure of the machine is based on a rotaxane, which is a molecular ring sliding along a molecular axle. The ring carries a thiolate group which removes amino acids in sequence from the axle, transferring them to a peptide assembly site. In 2018, the same group published a more advanced version of this concept in which the molecular ring shuttles along a polymeric track to assemble an oligopeptide that can fold into a α-helix that can perform the enantioselective epoxidation of a chalcone derivative (in a way reminiscent to the ribosome assembling an enzyme). In another paper published in Science in March 2015, chemists at the University of Illinois report a platform that automates the synthesis of 14 classes of small molecules, with thousands of compatible building blocks. In 2017 David Leigh’s group reported a molecular robot that could be programmed to construct any one of four different stereoisomers of a molecular product by using a nanomechanical robotic arm to move a molecular substrate between different reactive sites of an artificial molecular machine. An accompanying News and Views article, titled ‘A molecular assembler’, outlined the operation of the molecular robot as effectively a prototypical molecular assembler.
This is a sequence from a 3-minute animation that examines a unique formulation for building an effective therapy using the latest in nanotechnology, including monomers that organize into a controlled, self-assembling nanotube.
We worked very closely with our clients to deliver a detailed, accurate visualization of key attributes such as nanotube morphology, organization of dimers, and overall formation of the lanreotide nanotube.
